Course report (43-page pdf)

Refresher Course in Physics(7–27 September 2010)

Organised byDepartment of Physics, Panjab University, Chandigarh

in association withAcademic Staff College, Panjab University, Chandigarh

Course CoordinatorProf. C.S. Aulakh

http://physics.puchd.ac.in/events/2010-2011/20100907.html

Contents

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Department of Physics, Panjab University: A profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Schedule of the course . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Resource persons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Participants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Session reviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Some pearls of wisdom collected from various talks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

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Preface

The Physics Department at Panjab University was asked to take up the challengingtask of organising a Refresher Course in Physics after a gap of some years. Due tosome contingent factors the course was organised collectively by a committee of seniorprofessors, namely Dr. M.M. Gupta, Dr. J.B. Singh, Dr. A.K. Bhati and Dr. Suman Bala(retd.), convened by myself as Department Chairman and Associate Professor Dr. C.Nagaraja Kumar as the Organising Secretary. With such a battery of knowledge andexpertise available the normally onerous task of selecting and inviting the best availablespeakers became easy. With contributions from the professors and the whole-hearteddedication of Dr. C.N. Kumar to the organisational duties we were able to conducta lively and stimulating refresher course with a variety of talks in advanced areas ofphysics as well as discussion of pedagogical philosophies and methods.

Our participants belonged to a gamut of backgrounds. Five participants were fromour department itself and, in addition to those from neighbouring states, there wereparticipants also from Maharashtra and Madhya Pradesh. The participants were uni-formly enthusiastic and keen to hear about latest developments and there were livelydiscussions specially after the review talks presented by participants of the previousday’s lectures. The spirited and keen discussions made it clear that this was a meetingof colleagues and not students and a teacher. Many participants expressed their appre-ciation of the course lectures, beautiful campus and city and urged the Department toconduct such courses regularly. We look forward to doing so.

Charanjit S. AulakhCoordinator

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Department of Physics, Panjab University: A profile

After partition in 1947 the Physics Department of Panjab University then in Lahore washoused in Govt. College, Hoshiarpur (Punjab). In August 1958, the Department wasshifted to the present campus. At that time, the Department was headed by Prof. B.M.Anand who had worked with Nobel laureate C.F. Powell. The faculty numbered abouta dozen and Prof. Anand soon established a high-energy particle physics group (nuclearemulsion) and optical UV spectroscopy group. The experimental nuclear physics groupand mass spectrometry section came into existence soon after.

With Prof. H.S. Hans joining the Department in the late sixties, the research activitiesgot a major fillip—cyclotron was installed. Three major research groups in nuclearphysics, particle physics and solid-sate physics including both theory and experimentswere strengthened and mass spectroscopy laboratory was modernised. Since thenDepartment never looked back. It has UGC Special Assistance Programme (SAP) from1980 to 1988 and College Science Improvement Programme from 1984 to 1991. Withthe success of the above programs and of research activities in particle physics, nuclearphysics and solid-state physics through national and international collaborations, theDepartment became a major research center amongst Indian universities.

In 1988, the department was accorded the status of Center of Advanced Study(CAS) by UGC with three major thrust areas, particle physics, nuclear physics andsolid-state physics, which is a unique feature in itself. The department is now inCAS forth phase. At present the department has a strength of 27 faculty members, 47non-teaching/administrative staff, around 120 research students, 15 M.Phil. students,10 Post-M.Sc. Course in Accelerator Physics students and about 350 graduate andundergraduate students. Our students clear various entrance examinations like GRE,BARC, TIFR, DRDO, UGC/CSIR test for research and career in teaching, besides enteringprofessional courses M.Tech., MCA etc.

Besides imparting quality education to the department students, the faculty alsoteaches specialisation subjects, like nano-technology, nuclear medicine and medicalphysics to name a few.

The faculty members have been honored with Meghnad Saha award, Hari Om TrustAward, DAE Young-Scientist award and N.S. Satyamurthy award. They have beenelected for Indian Academy of Science fellowship, Joliot Curie fellowship, Alexandervon Humboldt fellowship, DAAD fellowship, Fulbright fellowship, Commonwealthfellowship, Third World fellowship UGC National Lecturer fellowship and DAE Ram-mana fellowship awards. Professor Yashpal, former UGC chairman, was faculty mem-ber of this department and Prof. H.S. Hans is presently PU Emeritus Professor andProf. K.N. Pathak, Ex-Vice-Chancellor, Panjab University, is with us as UGC ProfessorEmeritus.

Experimental high-energy physics (EHEP) group is participating in several inter-national collaborations namely, WA93, WA98, L3, EMU01, CMS and ALICE at CERN(Switzerland), Belle Experiment at KEK Japan and DZERO experiment at Fermi Lab(USA). The DZERO experiment participated in the discovery of top quark (1995) whereas WA93 and WA98 searched for new phase of matter quark-gluon plasma whosediscovery was announced in 2000.

At the national level the EHEP group is participating vigoursly in Indian NeutrinoInitiative collaboration and in experiments at VECC, Kolkata. Theoretical high-energy

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physics (THEP) group has made important contributions which are well recognisedat the national and international level. Some of the well recognised contributions ofthe group concern: (i) formulation and analysis of consistent minimal supersymmetricmodels of the corresponding grand unified theories, (ii) texture specific mass matricesand CP violation and (iii) proton spin crisis.

Experimental nuclear physics group has several national and international collabo-rations and is engaged in the study of nuclear structure at high spin, reaction dynamicsand mechanism, coulomb excitation and hyperfine interactions, x-ray fluorescence spec-troscopy for photo-ionisation processes and PIXE for element analysis using cyclotronat Chandigarh, 3 UD-Pelletron at IOP, Bhubaneswar and 15 UD-Pelletron at Inter-University Accelerator Center (IUAC) at New Delhi. Theoretical nuclear physics groupis studying the fusion, cluster-radioactivity at low energies and multi-fragmentation,nuclear flow and its disappearances and particle production at intermediate energies.

Experimental nuclear physics group research work is to get extra boost with thesanction of 5-UD Tandetron accelerator facility by DST (Govt. of India) to the PanjabUniversity. This facility shall be situated in the PU campus and the initial formalitiesfor the execution of the project are currently underway.

Theoretical solid-state physics group has several national and international col-laborations and is working on doped and undoped carbon clusters, fullerene solids,nanoparticles and nanotubes, theory of classical and quantum liquids and glass transi-tions, besides electron correlation in three-, two- and one-dimensional quantum chargedBose and Fermi liquids. Experimental solid-state physics group is engaged in the studyof the electrical and photo-electrical properties of pure and amorphous chalcogenidesand effect of metallic diffusion in compound semiconductors.

The other groups in the department are engaged in nonlinear dynamics, noncommu-tative field theories on the theoretical front while mass spectrometry group is engagedin the geo-chronological studies of Himalayan rocks. Theoretical astrophysics grouprecently started working on the galactic chemical abundance evolution (GCE) model tounderstand the complete galactic elemental (isotopic) evolution of galaxies.

The department besides participating in various national and international researchinitiatives also hosts various conferences, seminars, meetings etc. of research interestregularly. Some of the recent events hosted by the department are DAE symposia in HEP(1998), Nuclear Physics (1999), Solid-State Physics (2000) and DST summer school inEHEP (2005), XV Annual Convention of Indian Association of Physics Teachers (2000),6-day residential programme for undergraduates students on Physics Learning Camp(2007), DST SERC School in THEP (2010), Refresher Courses in Physics, seminars underTheoretical Physics Seminar Circuit Programme (TPSC) besides observing NationalScience Day every year. The department organises periodically open house programmeand is planning to start hands-on experiments laboratory. The department also has11-inch telescope to encourage/inculcate the scientific temper among public and withparticular emphasis on college and school students.

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Schedule of the course

Week I

09:30 –10:00

10:00 – 11:30 11:30 –12:00

12:00 – 01:30 01:30 –02:30

02:30 – 04:00 04:00 – 04:30

2010-09-07 Registration(09:00 – 10:00),Inaugural function(10:30 – 11:30)

Teabreak

Ice breakingsession

Lunchbreak

MIT and itsramifications inphysics I (C.S.Aulakh)

Project/paperpreparation

2010-09-08 Reviewsession

MIT and itsramifications inphysics II (C.S.Aulakh)

Teabreak

Introduction tonano materials(K. Dharamvir)

Lunchbreak

Nature ofphysical reality(ManmohanGupta)



The elusiveneutrinos(BrajeshChoudhary)

Teabreak

Accelerators,detectors andphysics at theLarge HadronCollider(BrajeshChoudhary)

Lunchbreak

Computerarchitectureand micropro-cessors I(NavdeepGoyal)



Physicseducationresearch: Anoverview (P.K.Ahluwalia)

Teabreak

Preparing forPER: A casestudy fromsolid-statephysics (P.K.Ahluwalia)

Lunchbreak

Low-costexperiments inphysics (M.S.Marwaha)



Developmentand testing ofconceptinventory (P.K.Ahluwalia)

Teabreak

Statisticalmechanicsconcept survey(P.K.Ahluwalia)

Lunchbreak

Library session Project/paperpreparation

2010-09-12 Sunday

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Week II

09:30 –10:00

10:00 – 11:30 11:30 –12:00

12:00 – 01:30 01:30 –02:30

02:30 – 04:00 04:00 – 04:30


Nano materials(K. Dharamvir)

Teabreak

Cyclotron visit(K.P. Singh)

Lunchbreak

Radiationeffects andsafety (A.K.Bhati)



Quantuminformation I(Arvind)

Teabreak

Quantuminformation II(Arvind)

Lunchbreak

Computerarchitectureand micropro-cessors II(NavdeepGoyal)



Quantumcryptography(Arvind)

Teabreak

Art of symboliccomputing I(R.C. Verma)

Lunchbreak

Art of symboliccomputing II(R.C. Verma)



Structure andproperties ofnewcarbon-basedmaterials –Fullerens,graphenes andcarbonnanotubes (V.K.Jindal)

Teabreak

Calculation ofband structureand phonons inmaterials aswell as ingraphenes andcarbonnanotubes (V.K.Jindal)

Lunchbreak

Basics of QGP(M.M.Aggarwal)



Computer lab Teabreak

Nuclear modelsand theirapplications I(S.S. Malik)

Lunchbreak

Nuclear modelsand theirapplications II(S.S. Malik)



StandardModel I(ManmohanGupta)

Teabreak

Stellarevolution andnucleosynthesis(SandeepSahijpal)

Lunchbreak

Library session Project/paperpreparation

2010-09-19 Sunday

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Week III

09:30 –10:00

10:00 – 11:30 11:30 –12:00

12:00 – 01:30 01:30 –02:30

02:30 – 04:00 04:00 – 04:30


Computer lab Teabreak

Origin andevolution ofsolar system(SandeepSahijpal)

Lunchbreak

Basicelectronics –circuit theory(D. Mehta)



GUTs (C.S.Aulakh)

Teabreak

Physics lab Lunchbreak

Project/paper presentations


Introduction onrecent advancesin nuclearphysics (RanjanBhowmik)

Teabreak

Exotic nuclearshapes (RanjanBhowmik)

Lunchbreak



High-spinphenomenon(RanjanBhowmik)

Teabreak

Project/paperpresentations

Lunchbreak


2010-09-24 Visit to TBRL2010-09-25 Review

sessionStandardModel II(ManmohanGupta)

Teabreak

Computersimulations(TankeshwarKumar)

Lunchbreak

Library

2010-09-26 Sunday

Last day

09:30 – 11:00 11:00 –11:30

11:30 onwards 02:30 onwards

2010-09-27 Nano-fluidics(TankeshwarKumar)

Feedback Tea break,Valedictory function,Lunch break

Payment of TA, DA at ASC

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Resource persons

1. Prof. Arvind, IISER, Mohali

2. Prof. M.M. Aggarwal, Department of Physics, PU, Chandigarh

3. Prof. P.K. Ahluwalia, Department of Physics, HPU, Shimla

4. Prof. C.S. Aulakh, Department of Physics, PU, Chandigarh

5. Prof. A.K. Bhati, Department of Physics, PU, Chandigarh

6. Dr. Vipin Bhatnagar, Department of Physics, PU, Chandigarh

7. Dr. Ranjan Bhowmik, IUAC, New Delhi

8. Prof. Brajesh Choudhary, Department of Physics & Astrophysics, University ofDelhi, Delhi

9. Prof. K. Dharamvir, Department of Physics, PU, Chandigarh

10. Dr. Navdeep Goyal, Department of Physics, PU, Chandigarh

11. Prof. Manmohan Gupta, Department of Physics, PU, Chandigarh

12. Prof. V.K. Jindal (Retd. from Department of Physics, PU, Chandigarh)

13. Dr. Tankeshwar Kumar, DCSA, PU, Chandigarh

14. Dr. S.S. Malik, Department of Physics, GNDU, Amritsar

15. Mr. M.S. Marwaha, SGGS College, Sector 26, Chandigarh

16. Dr. D. Mehta, Department of Physics, PU, Chandigarh

17. Dr. Sandeep Sahijpal, Department of Physics, PU, Chandigarh

18. Prof. K.P. Singh, Department of Physics, PU, Chandigarh

19. Dr. S.K. Tripathi, Department of Physics, PU, Chandigarh

20. Prof. R.C. Verma, Department of Physics, Punjabi University, Patiala

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Participants

1. Annu SharmaAssistant Professor, Department of Physics, Kurukshetra University, KurukshetraEmail: [email protected]: 9416655098 (Mb.)Expertise: Material modification by ion-beam treatment

2. Ashok KumarAssistant Professor, Department of Physics, Panjab University, Chandigarh 160014Email: [email protected]: 9041908468 (Mb.)Expertise: Experimental nuclear physics, application of accelerators

3. Baljinder KaurLecturer in Physics, Dept. ASH, Yadavindra College of Engineering, PunjabiUniversity Guru Kashi Campus, Talwandi Sabo, Dist. Bhatinda (Pb.)Email: [email protected]: 9646100419 (Mb.)

4. Bivash Ranjan BeheraAssistant Professor, Department of Physics, Panjab University, Chandigarh 160014Email: [email protected]: 0172 2534461 (Off.)Expertise: Experimental nuclear physics, application of accelerators

5. Madan Anantgir GiriAssistant Professor in Physics, Gramin Mahavidyalay, Vasantnagar, Mukhed,Dist. Nandel (M.S.) 431715Phone: 9423440996, 9673477855 (Mb.)Expertise: Material science (glasses)

6. Gurinder SinghAssistant Professor in Physics, SSG Panjab University Regional Centre, Hoshiarpur(Pb.)Email: [email protected]: 9501811977 (Mb.)Expertise: Material science

7. Inderjit Singh MangatLecturer in Physics, Khalsa College, Patiala (Pb.)Email: [email protected]: 9815846360 (Mb.)

8. Jangvir Singh ShahiAssistant Professor, Department of Physics, Panjab University, Chandigarh 160014Email: [email protected]: 9815612645 (Mb.)Expertise: Electronics, XRF

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9. JyotsnaAssistant Professor in Physics, NSCBM Govt. P.G. College, Hamirpur (H.P.)Email: [email protected]

10. Kuldeep KumarAssistant Professor, Department of Physics, Panjab University, Chandigarh 160014Email: [email protected]: 9417394110 (Mb.)Expertise: Theoretical high-energy physics

11. Lokendra Kumar BorkerAssistant Professor in Physics, RVPS Govt. College, Umaria (M.P.)Email: [email protected]: 9425560064 (Mb.)

12. Manohar Lal KaushalAssistant Professor in Physics, GGDSD College, Hariana, Hoshiarpur (Pb.)Email: [email protected]: 9478533662 (Mb.), 01886 250041 (Off.)

13. Rohan KaushalAssistant Professor in Physics, DAV College, Sector 10, ChandigarhEmail: [email protected]: 9417889348 (Mb.)Expertise: Theoretical condensed-matter physics

14. Sarvpreet KaurAssistant Professor in Physics, Govt. College for Girls, Sector 11, ChandigarhEmail: [email protected]: 9872801747 (Mb.)Expertise: Molecular spectroscopy

15. Padmakar Arjun SavaleAssistant Professor in Physics, Arts and Science College, Bhalod, Dist. Jalgaon(M.S.) 425304Email: [email protected]: 9881586841 (Mb.)Expertise: Electronics, biosensors

16. Shaminder Singh SandhuAssistant Professor in Physics, DAV College, Sector 10, ChandigarhEmail: [email protected]: 9872313570 (Mb.)Expertise: Theoretical condensed-matter physics

17. Sunita SrivastavaAssistant Professor, Department of Physics, Panjab University, Chandigarh 160014Email: [email protected]: 9876437838 (Mb.), 0172 2727563 (Res.)Expertise: Theoretical physics, nano-material physics

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18. Surendra KhandayatAssistant Professor in Physics, Govt. College, Nainpur, Dist. Mandla (M.P.)Email: [email protected]: 9424310405 (Mb.)

19. Tribhuvan Narayan SooryaLecturer in Physics, Vardhaman College, Bijnor 246701 (U.P.)Email: [email protected]: 9412606840 (Mb.)Expertise: Liquid crystals

20. Vishal KumarLecturer in Physics, Govt. Women PG College, Kandhla, Muzaffarnagar (U.P.)Email: [email protected]: 9219857772, 9457128220 (Mb.)Expertise: Material science (ceramics)

Members of academic committee

1. Bivash Ranjan Behera

2. Madan Anantgir Giri

3. Ashok Kumar

4. Kuldeep Kumar

5. Vishal Kumar

6. Padmakar Arjun Savale

7. Tribhuvan Narayan Soorya

8. Sunita Srivastava

Members of hospitality committee

1. Baljinder Kaur

2. Sarvpreet Kaur

3. Manohar Lal Kaushal

4. Inderjit Singh Mangat

5. Shaminder Singh Sandhu

6. Jangvir Singh Shahi

7. Gurinder Singh

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Session reviews

Inaugural function and ice breaking session

Session review by Madan A. Giri

Prof. A.S. Ahluwalia, Dean, Science Faculty, Panjab University, Chandigarh inaugu-rated the Refresher Course in Physics being conducted by the Department of Physicsand the Academic Staff College, Panjab University, Chandigarh from September 7 to27, 2010. He welcomed all the participants coming from all over India for this refreshercourse. He described the importance of refresher courses and gave a brief history ofthe university mentioning that Panjab University was originally established at Lahore.After the partition, the University functioned for almost a decade without having acampus of its own and then the University was relocated at Chandigarh.

He briefly mentioned about the various research projects going on in this universityand that the university has got a PURSE grant of Rs. 30 crore from the UGC.

In the inaugural session, Prof. C.S. Aulakh, Coordinator of the departmental organ-ising committee, introduced himself and other members of the committee to the par-ticipants. Other members are Prof. Manmohan Gupta, Prof. Suman Bala Beri, Prof. J.B.Singh, Dr. A.K. Bhati and Dr. C.N. Kumar. He highlighted the research contribution ofthe members of the committee at the national and international level. He mentionedthat the faculty of the department work in the thrust areas of are high-energy physics,nuclear physics and condensed-matter physics, both in theory and experiment. Somefaculty members also work in astrophysics and other areas. It was a good experienceto know about the department and the university.

After that all the participants introduced themselves. Various committees, such asthe academic and hospitality committee, were constituted. Prof. Aulakh briefed aboutthe evaluation process of the participants, emphasised on attending all the lecturesduring the course and hoped that all the participants will benefit from this course.

MIT and its ramifications in physics I

Resource person: C.S. AulakhSession review by Kuldeep Kumar

Rather than discussing all that is there in the textbooks, it is more useful to thestudents if the teacher highlights the central idea, which is widely applicable, and thestudents are able to appreciate that. One such simple, widely applicable idea is atheorem in matrix algebra, which Prof. Aulakh calls MIT or most important theorem inphysics.

The lecture started with an elementary discussion of the eigenvalue problem inmatrix algebra. When a square matrix multiplies vectors (column matrices) from the left,it transforms these vectors into other vectors which, in general, are not just multiples ofthe original ones. However, there are particular vectors of importance, each of which istransformed by a given matrix into a multiple of itself. Any such nonzero vector is calledan eigenvector of the given matrix and that particular multiplicative constant is calledthe corresponding eigenvalue. Generally, one is interested in finding the eigenvaluesand the corresponding eigenvectors of a given matrix and a consistency requirement

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yields the so-called characteristic equation involving a polynomial of degree N if thesquare matrix in question is of order N. This equation has precisely N roots followingthe fundamental theorem of algebra. These roots are the eigenvalues, which may not beall distinct. Then one determines the eigenvectors corresponding to these eigenvalues.

After introducing the concept of inner product, which is an extension of the usual dotproduct of vectors, Prof. Aulakh then talked about Hermitian matrices—the matriceswhich equal their transposed conjugate. He pointed out the role of matrices as operatorsin quantum mechanics and of vectors as states of a physical system. He also cited thedefining property of Hermitian matrices in terms of the inner product of two vectors.

After this mathematical background, then Prof. Aulakh focussed on his most im-portant theorem in physics which he discussed at length. This well-known theoremstates that the eigenvalues of a Hermitian operator are real and the eigenvectors corre-sponding to different eigenvalues are orthogonal. In quantum mechanics, Hermitianoperators of interest, quite often, represent some physical variable and it is a funda-mental postulate of quantum mechanics that any measurement of an observable canonly yield one of the eigenvalues of that operator.

Prof. Aulakh also deliberated on the topics of diagonalisation and spectral decompo-sition of Hermitian operators. He briefly outlined the Gram-Schmidt orthogonalisationprocedure in a simple way. He then discussed the completeness of eigenvectors of aHermitian operator. The set of all eigenvectors of a Hermitian operator is, in general,a complete set, which means that any arbitrary vector can be expanded in terms ofthem. Eigenvectors belonging to different eigenvalues are orthogonal. In case of de-generacy, when there are two or more linearly independent eigenvectors belonging tothe same eigenvalue, one can construct their appropriate linear combinations which areorthogonal and belong to the same eigenvalue. If the eigenvalues are non-degenerate,they can be used to label the corresponding eigenvectors. In case of degeneracy, theeigenvalues of some other commuting observable can be used to discriminate betweenthe degenerate eigenvectors.

Finally, he discussed the wide applicability of his most important theorem in physics,particularly in the study of special functions, differential equations, etc. He also brieflymentioned Dirac’s famous bra-ket notation, sequential Stern-Gerlach experiments andtheir analogy with the polarisation of light as discussed in Modern Quantum Mechanicsby J.J. Sakurai.

Prof. Aulakh worked out all the mathematical details on blackboard in a systematicand coherent manner. He enthusiastically and successfully highlighted, in very simpleterms, the idea of his most important theorem and its ramifications in physics. Afew participants might have found this lecture too elementary but for most of us thisengaging lecture has been useful.

MIT and its ramifications in physics II

Resource person: C.S. AulakhSession review by Rohan Kaushal

In sequence with his earlier lecture Prof. C.S. Aulakh continued with the conse-quences of MIT in Physics. He began this sequel of his first lecture with the statement,“If two observables are such that their corresponding operators commute then they can

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be simultaneously diagonalised”. He elaborated the statement with a mathematicalformulation. It was mentioned that Hilbert space could be divided into a large numberof subspaces having different elements and dimensions. The orthonormality condi-tion for a collective index along with its closure property or the completeness relationwas discussed and these conditions were termed as the most important conditions.Dr. Aulakh then told the participants that quantum mechanics obeys the principle ofsuperposition and so does the classical electrodynamics. Terming the Hilbert spaceas normalisable vector space he mentioned that the Hermitian inner product obeysSchwarz’s inequality. The triangular inequality was also mentioned briefly. Referringto the discussion with Prof. M.M. Gupta he mentioned that the result of a measurementwas a real number which in mathematical picture corresponds to Hermitian operator.In a lighter vein Dr. Aulakh mentioned that physics was not complicated but the peo-ple were. He tried to explain the mathematical steps in a precise but simple manner.However some of the steps were not that simple for some of the people, at least priorto his lecture. Some of the participants felt the need of more elaborative examples.

Prof. Aulakh talked about the infinite dimensional vector space and also gave anexample of one dimensional case by considering a particle moving on a real line followedby mathematically well woven equations involving the Dirac delta function. He brieflydiscussed the translation operator and unitary transformations along with the fact thatthe unitary transformations preserve the length or norm of a vector. He also showedthe participants the correct way to express a matrix element of an operator. Towards theend separate partial differential equations and Stern-Liouville operator were discussedfollowed by a brief mention of the Green’s function. In the end he briefly mentionedhis personal experience with Michio Kaku and also mentioned few of Kaku’s books.

It was an interesting lecture which involved the extensive use of blackboard andrefreshed the fundamentals of quantum mechanics in our memories from the M.Sc.times. Though some of the participants felt that the mathematics involved was rigorous,it was also felt that hidden behind all those interesting and fascinating results of Physicsare the rigorously solved mathematical equations and their physical significances. Soit is also very necessary to understand the basic mathematical formulation in order totruly appreciate the fascinating physical phenomena.

Introduction to nano materials

Resource person: K. DharamvirSession review by Baljinder Kaur

Prof K Dharamvir gave very informative and interesting lecture in the second ses-sion. She started the lecture with the basic information of nanoparticles and theircomposition by comparing them with bulk state. The nanomaterials are of size range10−9 m and can be metals, non-metals, semiconductors, ceramic, polymeric materialsand composites. The properties of materials changes as it enters the nanometre rangeas the surface to volume ratio increases. She emphasised on the importance of nanopar-ticles as their unique and unusual properties make them a very unique material witha whole range of promising applications. Nanoscience is an interdisciplinary sciencethat involves whole knowledge on fundamental properties of nanosize objects and notlimited to physics, chemistry, biology, medicine, materials, engineering and comput-ers. Then she talked about different types of microscopes with great emphasis on STM

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(scanning tunnelling microscope) as it gives highly magnified images of nanomateri-als.She told that nanomaterials exits in various forms as nanowires nanotubes, quantumdots, thin films, nanofibers, non porous filters, polymer composites etc and describe thevarious properties of nanomaterials which make them highly useful in various waysspecially in medicine and electronics. At the last she talked about the challenges beforethe nanomaterials as it is very difficult to have their controlled synthesis and finishedher lecture with brief talk on its future prospects and risks related to nanoparticles. Thislecture was appreciated by the participants as it contained valuable information.

Nature of physical reality

Resource person: Manmohan GuptaSession review by B.R. Behera

The lecture was basically a prelude to the basics of quantum mechanics and quantumfield theory or more appropriately an Introduction before we start a rigorous field theory.However, the concepts were presented in a philosophical tone, rather than starting withequations, wave functions and operator theory.

Prof. Gupta started his lecture pointing out that, most of the physics is explainedby solving mathematical equation and most of the students lack the conceptual under-standing of the physical problems. He emphasized the need of conceptual understand-ing, before we apply mathematics to the problem. His message to the audience wasmathematics should be supplemented by physical concepts.

In the second half he started with how a scientific theory is established. Firsta certain observation of the phenomena is performed. Based on the observation ahypothesis is formulated. Verification of the hypothesis is performed then a scientifictheory is established. He also mentioned that as the number of observables increases,we are bound to change our scientific theory. Scientific theories are based on a set ofobservables available at a particular time.

He went on explaining classical physics and said some of the every day phenomenacan’t be explained by classical rule. He gave the example of collision of two atomsand mentioned that there are no well defined trajectories for atoms and moleculesin the microscopic domain. He went on explaining how to observe atomic particles(Basically you need to shine this with photons or light with comparable wave length.Then he started the conceptual points required for understanding quantum mechan-ics. He explained the concept of wave functions, principle of superposition of states,the operators and the representation of transition probability in quantum mechanics.All these fundamental concepts he explained giving the example of Hydrogen atom,Polarization experiment in a tourmaline crystal and double slit experiment of Young.He also introduced the concept of Dirac—anti-particle, creation and annihilation pro-cess and what is quantum field theory (QFT). QFT is basically quantum mechanics ofcontinuous system. He gave the example of Lamb Shift, the radio frequency transitionbetween 2s1/2 and 2p1/2 levels of hydrogen atom and the existence of energy differenceof 1058 MHz between these two levels. The need to explain Lamb shift was a key factorwhich stimulated the development of quantum electrodynamics (QED). At the end ofhis lecture, he introduced QFT, starting with action, Euler-Lagrangian equation andquantization of the field.

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In summary his lecture was a revision of quantum mechanics and a short preparationfor learning particle physics. The lecture was presented in an entirely different fashionwith minimal use of mathematics.

The elusive neutrinos

Resource person: Brajesh ChoudharySession review by Ashok Kumar

Prof. Brajesh Choudhary started his talk discussing how the different philosophiesregarding the matter were evolved in different ancient civilizations. Then he briefedthe participants about the compositions of matter particles which are divided in twoclasses: leptons and Quarks. There are six particles of each class and six correspondingantiparticles. In addition, there are gluons, photons, and W and Z bosons, the forcecarrier particles that are responsible for strong, electromagnetic, and weak interactionsrespectively. These force carriers are also considered as fundamental particles. Hediscussed the continuous spectrum observed by Meitner and Otto Hahn in the decayof 60Co in 1911. W. Pauli (1930) suggested the existence of a neutral particle, he called itNeutron, with spin 1/2 to explain the spectrum. Later on in 1932, Fermi explained thecontinuous spectrum and coined the word ‘neutrino’ for this particle.

He explained how difficult is to detect this particle due to their extremely lowinteraction probability with matter. He also discussed the sources of neutrinos like sun,supernova explosion, reactors and accelerators. The idea of the neutrino oscillations inorder to explain the deficiency in detected solar neutrinos from the flux predicted byStandard Model was also discussed. He illustrated that how the neutrino oscillationmight happen and discussed the concept of mixing angle 2Θ and ∆m2 (mass squareddifference). He concluded that a necessary condition for them to occur is that neutrinoshave to have mass. The results of a number of experiments like MACRO, LSND,Kamiokande, Soudan 2, Super-Kamiokande and Sudbury Neutrino Observatory (SNO)performed to study the neutrino oscillations were also discussed. Super-K showeda strong zenith angle and energy dependent characteristics of an oscillations. SNOprovides the proof that electron neutrino is oscillating into neutrinos of other activeflavor. The results of KAMLAND, reactor electron anti-neutrinos experiment, are alsoin favor of neutrino oscillations. K2K and MINOS, long baseline experiments, alsoconfirms the deficit in observed muon neutrino events. He explained the differentaspects of SNO experiment in details and also discussed the neutral current, chargecurrent and elastic scattering. The present and future experimental efforts of the scientistto understand the neutrino which may bring the revolutionary conceptual changes inour understanding of physics and nature were also discussed. The efforts of IndianScientific community to establish the Indian Neutrino Observatory (INO) were alsothe point of discussion. His lecture was very informative , exciting and was aimedfor the general physics community and in the last it was also subject specific. All theparticipants enjoyed it and participated in the discussion.

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Accelerators, detectors and physics at the Large Hadron Collider

Resource person: Brajesh ChoudharySession review by Jyotsna

The session started with a few questions from the participants regarding the topicdiscussed by Dr. Brajesh Choudhary in his previous talk. He answered the queries andthen started his talk on detectors. He showed a clipping of MINOS FAR DETECTOR inFermi Lab where he worked.

Dr. Choudhary then discussed Large Hadron Collider (LHC) which is the mostpowerful particle accelerator in the world located in CERN. Here ‘Large’ correspondsto the size of an accelerator which is related to maximum energy obtainable. ‘Hadron’is any strongly interacting composite subatomic particle like neutron and proton and‘Collider’ is a machine where counter-circulating beams collide.

Dr. Choudhary told us that LHC is designed to collide two counter-rotating beamsof protons or heavy ions of energy 3.5 TeV per beam. He showed us a clipping ofLHC where the collider is housed inside a circular tunnel of circumference 27 km andabout 100 m underground. A variety of magnets such as dipoles, quadrupoles, etc. arealigned in the tunnel which are used for trajectory corrections of the particle beam toavoid quenching. He gave a very good comparison of fixed-target collision and collider.Then he briefly discussed the four particle detectors which have been constructed andhoused in huge underground cavern. These detectors detect the collisions that occur atfour intersection points. The detectors are ATLAS, CMS, ALICE and LHC-B.

In the end he highlighted the goals of LHC experiments, which are: (1) to testthe standard model with very high precision, (11) to search for dark matter, (iii) tounderstand the nature of big-bang theory and (iv) to search for Higgs boson.

Overall the lecture was very informative and valuable. There was a lot of interactionbetween the resource person and the participants throughout the lecture.

Computer architecture and microprocessors

Resource person: Navdeep GoyalSession review by J.S. Shahi

Dr. Navdeep Goyal started his talk by emphasizing the importance of design consid-erations of microprocessors for students opting for further studies in microelectronics.He suggested the participants to begin with basic principles of computer systems be-cause knowledge of the working of a simplest computer system is always helpful indeveloping a deeper understanding of the subject.

Dr. Goyal very nicely elaborated all basic components of a simple computer systemsuch as Data Bus, Address Bus, Control Bus, Tri-state Devices and Buffer Registers etc.In a detailed discussion the participants were explained the working of as simple aspossible 8 bit computer, popularly known as SAP-1, starting from the instruction setto a block diagram of its complicated control unit. The discussion became much moreelaborative and interactive by some basic queries from participants.

As the scope of this topic is very vast and the speaker wanted to discuss much moreso Dr. Goyal concluded his talk by promising another session for detailed discussionabout Microprocessors such as 8085 and 8086.

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Overall the lecture was very interesting and informative. It helped in understandingthe basics of a computer system in a very simple way.

Physics education research: An overview

Resource person: P.K. AhluwaliaSession review by Manohar Lal

Prof. Ahluwalia started his lecture with some questions like whether we are teachingscience in a scientific way, what the goal of education is and what the concerns are. Hediscussed Yashpal Committe report. He explained the cause of decline in the numberof students majoring in physics. He pointed out that subject based education researchhas three objectives of teaching and learning—literacy, numeracy and competency. Hedescribed competency building and its various facets, such as curriculum development,lab training innovation, teachers’ training, use of modern technology, changing pupil’sidea and reflection and metacognition.

Prof. Ahluwalia presented his lecture in a systematic, simple and logical way, ex-plaining his points with suitable examples. This thought-provoking lecture was enjoyedby all the participants.

Preparing for PER: A case study from solid-state physics

Resource person: P.K. AhluwaliaSession review by Gurinder Singh

Prof. Ahluwalia started his lecture by emphasising how the behavior of humanbeing is changed with teaching a subject. His presentation was divided into three parts:physics education research, need for learning objectives and missing links. There is anincreasing need felt for physics education research which is a fast growing and diverseresearch subfield of physics. He highlighted that syllabi of different universities are notdesigned in a proper manner; what is written in the textbooks forms the syllabus. Itsimplications are poor understanding of the subject; a student is able to derive only thederivations and is unaware about the physical context. In missing links he highlightedthe absence of instructive objectives and learning objectives. He defined them to bewhat a learner will be able to do after an instruction is given to him. He has given twoapproaches for this—Mager’s approach and Bloom’s taxonomy approach. In Bloom’staxonomy he emphasised on thinking and problem solving. Then he talked aboutthe magic triangle in which objectives, learning activities and evaluation are linkedtogether. Then he has drawn the instructive objective and learning objective tablefor undergraduate course in solid-state physics. He has also given examples fromnanotechnology, quantum dots etc. Then he gave another viewpoint to his lecture.In this viewpoint a student would be able to create a mental image of the work bydrawing maps. He has taken help from Lynch’s work. In the end he has encouragedthe participants to write a research paper in this area.

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Low-cost experiments in physics

Resource person: M.S. MarwahaSession review by T.N. Soorya

Dr. M.S. Marwaha emphasised the use of demonstration techniques in understand-ing various fundamental physics principles. He started with the demonstration ofFaraday’s law with the help of an electromagnet, a coil and a galvanometer. He showedthat how two secondary coils connected in series may have double or zero emf depend-ing on the phase of the emf in two coils. With this setup he also demonstrated Lenzlaw and the heating effect due to eddy currents. After that with the help of a hollowaluminium cylinder and a cylindrical magnet he demonstrated the concept of Lenz lawas well as terminal velocity and told that eddy current do not require any specific pathto follow. He further explained the Physics behind the magic of disappearing milk andshowed that the container is actually a double walled cylinder. The Fleming’s left handrule was demonstrated by passing a current in a household aluminium foil put in amagnetic field. He further demonstrated that the torque produced due to current flow-ing through the magnet can rotate the magnet itself. He further connected two balloonswith a hollow tube and showed that the phenomenon goes against our common sense.He also demonstrated experiments based on centripetal force, Bernoulli’s theorem andTorricelli’s theorem. He also showed us love thermometer, plasma globe and opticalillusion.

The session was very interactive and most of the participants actively took partin the discussion that followed the demonstration. In some cases the participants’explanation differed with that of the resource person. Overall the demonstration setupswere appreciated by the participants.

Development and testing of concept inventory

Resource person: P.K. AhluwaliaSession review by Sunita Srivastava

A concept inventory is a criterion-referenced multiple choice test designed to eval-uate whether a person has an accurate working knowledge of a specific set of concepts.Concept inventories are built in an multiple choice format to ensure that they can bescored in an objective manner and readily administered in large classes. Unlike a typicalmultiple choice test, however, both the question and response choices are the subject ofextensive research designed to determine both what a range of people thinks a partic-ular question is asking and what the most common answers are? The resource personfurther emphasized that these assessments should be rigorously evaluated to assurevalidity and reliability. In its final form, each question includes one correct answerand several other distracters, i.e. correct answers usually (but not always) based onstudent’s prevalent commonsense ideas (i.e. commonly held misconceptions). In fact acriterion- referenced is regarded as an instrument that determines the score of an indi-vidual by the amount of material mastered in a certain content area. The participantsthoroughly enjoyed the lecture and appreciated the great efforts of the resource person.In fact, there can be many aspects of learning that can be assessed. However, if weseek to empower students to transfer the knowledge gained to new situations, then adeep understanding must be developed which is associated with the understanding ofconcepts.

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Statistical mechanics concept survey

Resource person: P.K. AhluwaliaSession review by Vishal Kumar

Prof. P.K. Ahluwalia described in detail about his research work on statistical physicsconcept Survey. The Lecture was delivered in systematic way dividing the content inSubtopics mainly, Motivation, Literature Review, Methodology, Defining Themes, Dol-phi Study, Drafting of Multiple Type Questions, Interview with Students, Validity,Statistical Indicators Analyzed, A Bird’s Eye View of the Concept Survey, To WhomAdministered, Sample Size, When was the Test administered, Motivation to UndertakeTest for U.G., P.G. Students and Teachers, Preparation for the Test and Duration, Statis-tical Analysis of the Gathered Data, Conclusions, Hypothesis, Item Discrimination andLessons Learned from, Statistical Physics Concept Survey (Version 1.0).

In the lecture Prof. P.K. Ahluwalia told how he motivated the U.G., P.G. studentsand teachers to appear in the test to collect the data .Ten days advanced intimation wasgiven for the preparation of the test and the duration of the test was 45- 60 minutes.In the question paper there were 46 objective type questions in which 36 questionswere quantitative, 4 qualitative and 5 questions were on multiple representations. Thehypothesis was that if only less than 40% of the students are able to solve any questionthen that concept should be emphasized. The list of some standard research paperswas shown on the screen for literature survey.

He used the tables and graphs in very effective way to represent the data to givemeaningful information. He discussed some parameters like, Standard Deviation, ItemDiscrimination and Reliability and these values calculated from the gathered data. Asthe value of the Standard Deviation for the score of the test was 5.4 for U.G. students,5.37 for P.G. students and 8.99 for the teachers. Prof. P.K. Ahluwalia told about one ofthe conclusions of the study that the performance of P.G. students was better than theteachers in the test.

Through his lecture Prof. P.K. Ahluwalia described some good techniques useful forthe teaching of Physics. He also introduced a new field of research, Physics EducationResearch for which any costly experimental set-up is not required and the researchpapers produced can be considered for publication in reputed journals like, AmericanJournal of Physics and Physics Education.

He also discussed about the flaws of the instrument which can be removed in thenext version. One of the flaw of instrument was that there were such type of questionswhich can not be plotted in the graphs shown. The lessons learned were that thereshould be pre and post test, good distracters in form of the options of the multiplechoice type question and more topics should be covered.

Overall the lecture was informative and appreciated by the participants.

Nano-materials

Resource person: K. DharamvirSession review by Padmakar A. Savale

Prof. Keya Dharamvir discussed about modification in electronic properties of nanomaterials as quantum confinement, quantum size effect, electronic bands and electronic

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transition and charge quantization. Nano materials structure was classified as bulk,film, nanotubes-wires and nanoparticle clusters on the basis of spatial dimensions andconfinement dimensions. After that, the comparison of microstructures vs nanostruc-tures was explained on the basis of semi-classical and quantum mechanics.

Prof. Dharamvir described electronic behaviour in small sizes with the help ofenergy quantization, charge quantization and ballistic and focused on free electron casein 3D box. The concept of excitation was explained with the help of e-h pair boundedby attractive electrostatic interactions. The concept of strong and weak confinementwas illustrated in quantum confinement. This concept was elaborated with the densityof state by using 1D, 2D and 3D systems and she also focused on density of state,energy levels and DOS, size effect: controlled band gap tuning, discrete energy levels,1D quantum well states, optical spectra and tunable band gap.

Resource person emphasized that optical excitation is significantly enhanced bothin frequency and intensity. The energy gap was explained with the suitable diagram.The preparation and properties of nonmaterials, electronic band theory, energy bandstructure, electronic transition, direct and indirect transitions were also discussed. Shedescribed photo absorption in direct and indirect transitions in effective manner.

At the end, resource person stressed on optical properties of semiconductor nanopar-ticles, size classification, optical properties of metal nanoparticles, Tunnelling spec-troscopy of InAs QD, melting temperature of nanocrystals and thermodynamic be-haviour of metal clusters. Prof. Dharamvir quoted that as the cluster size decreases, themelting temperature monotonically decrease. However, when the cluster size is smallenough, Tm does not vary monotonically on cluster size.

The session was very helpful to understand the basic concepts of nonmaterials andtheir electronic and optical properties in a simple way.The participants participated inthe discussion actively. Overall the session was informative and appreciated by theparticipants.

Cyclotron visit

Resource person: K.P. SinghSession review by Shaminder Sandhu

Prof. K.P. Singh started his lecture with historical background of the cyclotron, hetold Prof. H. S. Hans was instrumental in bringing the variable energy cyclotron fromUSA, it started working in the year 1975. This is the oldest working cyclotron inthe world. He explained the protons to be accelerated are produced by bombardingHydrogen molecules with electrons, whereas electrons are produced by thermionicemission. He described vacuum tube oscillator as the heart of the cyclotron, respondingto a query he told if solid state device is used to replace the vacuum tube then couplingwill be the major problem.

He further explained this is a single Dee cyclotron with arrangement for frequencyvariation from 10 MHz to 15 MHz, and particles are accelerated once in each revolutionby radio frequency oscillator and large magnets are used to make the accelerating parti-cles to move in a circular path and finally the accelerated beam of particles so producedis transported to quaderpoles through a window and then a probe is used to maximizethe frequency. Analyser Magnetic lens makes the particles of different velocities to

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revolve in different trajectories and a slit produces waves of 30 kev broadening. Twobeams, one at 0◦ and other at 45◦ are produced, the beam produced at 45◦ is made tohit the target. For safety purpose, metallic walls of the cyclotron room are grounded.

He explained water based cooling system is used for cooling different parts &five diffusion pumps connected with a rotary pump create vacuum in the chamber &maintain pressure of the order of 10−6 mm of Hg. Prof. K.P. Singh explained how inthe target Chamber the particle induced x-ray/ gamma ray emission (PIXE/PIGE), andhigh purity Germanium (HPGe) detectors are used. Presently it’s being used to inspectthe element in the sample and secondly to find the amount of element available in thesample. For this analysis only software available in the world named as DUPIX is beingused.

Prof. K.P. Singh said in the past it was also used to produce isotopes, but now a daysits not being used for this purpose, he further added α particles can’t be acceleratedwith this cyclotron due to the limitation of high current requirements to magnets. Hesaid some changes have been made time to time in the cyclotron. Total 100 kW poweris required to operate cyclotron and its accessories.

Finally participants visited the control room and generator room and got first handexperience, how to control and operate the cyclotron. All the participants curiouslyparticipated and discussed their queries and have appreciated the visit to cyclotron andvaluable interaction with Prof. Singh.

Radiation effects and safety

Resource person: A.K. BhatiSession review by Annu Sharma

In the beginning of the talk itself Prof. Bhati mentioned that his talk is an informativelecture rather than a specialized talk. He defined radiation as the propagation ofenergy in the form of waves or particles which can be classified under two categories,depending on their mode of interaction as ionizing radiation or non ionizing radiation.When these radiation interact matter they either produce disordering of the crystallinestructure which leads to atomic displacements or Ionization which can cause changesin chemical or biological properties. Then he focussed his presentation on the effect ofradiation at biological level i.e. cellular level and on organisms. At cellular level theradiation interact with the DNA of the cell and can damage it by breaking of singlestrand or double strand of DNA and the effect of the radiation on organisms are oftwo kinds: deterministic effect and stochastic effect. He highlighted that there is noevidence on hereditary effect of the radiation in human population. While discussingthe principles and methods of radiation protection Prof. Bhati said that the aim ofradiation protection is to protect man and his decedents and of course environmentfrom harmful effects of radiation. In the end he emphasized on the management ofradioactive waste in India.

The talk was very interesting and of social importance. It assumes further signif-icance in the light of the recent radioactive leakage that occurred in Delhi and aboutwhich we all know. We as physics teachers should assume this responsibility to teachour students how to handle radioactive sources safely so that this knowledge getsdisseminated in the society. The talk by Prof. Bhati was organized in a very effectivemanner.

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Quantum information I

Resource person: ArvindSession review by Rohan Kaushal

In the beginning of this interesting lecture Dr. Arvind first of all comforted the par-ticipants by giving them the liberty to interrupt him in between his lecture wheneverand wherever they felt like. He started his lecture by drawing the attention of the par-ticipants to a general question which had created a lot of interest among the researchersthat whether there was a fundamental limit to the computation in terms of power con-sumption. He informed us that the power consumption has reduced remarkably evenwith the increased speeds of processors because of the advancements in the technologywith the passage of time. He mentioned that the computations in the present day com-puters were the irreversible processes and also drew the attention of the participants tothe question whether these could be made reversible. Summing up some historical factsDr. Arvind told the participants that in 1984 Feynman gave a model for the quantumcomputing in which the process of computation was reversible and there was no roleof uncertainty principle. He also informed the participants that it was only in 1995 thatsome work on this model was done in actual sense. He told the participants that it wasPeter Shor of Bell Labs, currently working as the Professor in Applied Mathematics atMIT, USA, who showed that how a quantum computer could perform factorization inpolynomial time which otherwise on a classical computer takes an exponential time.He supported his arguments with a nice mathematical explanation. He also showedhow certain problems could not be solved even in the whole lifetime of the universe ifcarried out on a classical computer.

Dr. Arvind then classified the classical and quantum computers very nicely. Heintroduced the participants to the concept of CNOT gate and also showed how thissimple circuit can replace the conventional NAND gates in the processors so that theprocess of computation could be made reversible which there by meant that one couldknow by seeing the output what the inputs were. Explaining the fundamentals of aquantum computer he mentioned how the spin half system could be considered as thesimplest example of a quantum system. He also explained the logics on the basis ofstates of the particles and the unitary transformations and gave examples of the thingswhich could be used for the input purposes to carry out a quantum computation.

He made no use of power point presentation and used only the black board and thecoloured chalks in a very systematic manner. This made the participants think that therewas still no better alternative to the black board when it comes to teaching. His way ofexplaining the things was very good and illustrative and the language was so simplethat the mathematics and quantum mechanics involved was easily understandable.The lecture was quite informative and exposed the participants to this newly emergingarea in research in the field of computation.

Quantum information II

Resource person: ArvindSession review by Sunita Srivastava

Quantum Information is physical information that is held in the ‘state’ of a quantumsystem. The fact that information is physical means that the laws of quantum mechanics

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can be used to process and transmit it in ways that are not possible with existingsystems. The most popular unit of quantum information is the qubit, a two levelquantum system which can be a superposition of two states at any given time. Theability to manipulate quantum information enables us to perform tasks that wouldbe unachievable in classical context. The resource person presented his lecture in avery lucid and interesting manner which impressed his audience to a great extent. Heexplained to the participants how in place of bits, the new quantum information theoryhas qubits which are capable of entanglement and superposition and interact with oneanother via quantum gates. This followed by explaining in a beautiful manner thatwhere can we use the quantum computer in a non-trivial way. He further told theparticipants as to how to exploit the superposition principle by taking the example ofa spin ¡ which can be considered as qubit. He also mentioned about the famous ‘TOYPROBLEM’ and introduced the concept of a constant or balanced function. Quantumcomputation was further simplified with the help of a Halamord Gate and Quantumoracle. The overall introduction to this important concept by the resource person wasa wonderful attempt which was greatly appreciated by the participants.

Computer architecture and microprocessors II

Resource person: Navdeep GoyalSession review by Surendra Kumar Khandayat

Dr. Navdeep Goyal started his lecture with microprocessor requirements. He toldus that microprocessor should be able to handle large memory,it should have a fasterspeed and capability to deal with input and output devices. He further explainedthat system should have bus driver to handle the current mismatch, decoders forinput/output devices, latches to lock the information for certain interval of time. Toencode the information from input device an encoder has to be used. He then talkedabout 8085 microprocessor. It has a multiplex data bus i.e. shared data bus. Heexplained address signal ALE, RD, WR, I/O memory, serial output and input. He alsofocussed on externally initiated signals, interrupts, HOLD, READY, RESET IN andserial I/O ports.

He explained Demultiplexing Address Data bus, generating control signals and ar-chitecture of 8085 microprocessor. The architecture of 8085 contains accumulator, sixprogrammable registers, temporary registers, stack pointer, program counter, instruc-tion registerand instruction decoder, interrupt control and serial output control, flgsand ALU etc. Dr. Navdeep explained complete block diagram of 8085 microprocessor,system based upon 8085 microprocessor and static RAM. He defined the interfacingmemory and interfacing I/O devices.

He then discussed about precautions that has to be taken while interfacing memorydevices. He talked about advanced microprocessors. He told that the performance ofthe processor cannot be increased with simply increasing the clock frequency but onehas to add parallelism to increase the number of instructions per cycle that is calledinstruction level parallelism. In the end he briefly explained IBM Xenon i.e. three coreprocessor and told that eight core and sixteen core processors will be available in marketsoon.

The talk was very informative and knowledgeable. The participants actively tookpart in the discussion that follow the lecture.

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Quantum cryptography

Resource person: ArvindSession review by Sunita Srivastava

Quantum cryptography uses our current knowledge of physics to develop a cryp-tosystem that is not able to be defeated i.e. one that is completely secure against beingcompromised without knowledge of the sender or the receiver of the messages. Theword quantum itself refers to the most fundamental behaviour of the smallest parti-cles of matter and energy. The resource person emphasized the fact that the quantumcryptography is different from traditional cryptographic systems in that it relies moreon physics, rather than mathematics, as a key aspect of its security model. Essentiallyquantum cryptography is essentially based upon the usage of individual photon andtheir intrinsic quantum properties to develop an unbreakable cryptosystem essentiallybecause it is impossible to measure the quantum state of any system without disturbingthat system. It is theoretically possible that other particles can be used but photon offersall the necessary qualities needed, their behaviour is comparatively well understoodand they are the information carriers in optical fiber cables, the most promising mediumfor extremely high bandwidth communications. The fact is that practically its usagedepends upon many factors including transmission distance, expense and ease of use.However, it is found that (not mentioned by resource person) Quantum Cryptographymight provide everlasting security but only if it is well implemented. Based on theHeisenberg uncertainty principle in which observation causes perturbation, anyonetrying to eavesdrop on a Quantum Key Distribution system should quickly be discov-ered. To everybody’s shock, experts have developed and demonstrated a techniqueexploiting imperfections in quantum cryptography systems to implement an attack. Infact, commercial systems usually use photon light signals within network equipmentwhich leave them open to attack. The lecture presentation was very effective and wellreceived by the participants.

Art of symbolic computing I

Resource person: R.C. VermaSession review by T.N.Soorya

Prof. R.C.Verma started his talk with providing us useful information about NationalMission on Education through Information & Communication Technology especially itsSakshat portal. He then moved to his main talk on Symbolic Computing I. The Symboliccomputing is concerned with the representation and manipulation of information insymbolic form. It is often contrasted with numeric representation. He divided histalk in three parts. In first part he introduced us to Mathematica which is a fullyintegrated environment for technical and scientific computing. Mathematica combinesnumerical and symbolic computation, visualization, and programming in a single,flexible interactive system. He explained the input output commands and various builtin functions available with the package. In the second part he discussed the power ofMathematica and told that it can do factorisation of algebraic functions, solve linear aswell as polynomial equations and you can also create user defined functions. In the thirdsection of his lecture he focussed on the graphic aspect of the Mathematica and showedthat 2D and 3D plots can be made with much ease in Mathematica while it is very toughand challenging in other languages. At this point concept of interactive graphics was

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introduced to us. In the end with the help of suitable diagrams he explained how wecan easily visualise a Vector field and Gradient of a Scalar field.

Overall the talk was very informative and contains a lot of information. It introducesus the concept of symbolic computation. It would have been better if such type of talkswere held in the Computer Lab, so that participants might have a firsthand experienceof various commands.

Art of symbolic computing II

Resource person: R.C. VermaSession review by T.N.Soorya

In Continuation to his earlier lecture Dr. R.C. Verma discussed about Programmingin Mathematica, Calculus and Issues related to Computational Physics. In the begin-ning he told that Mathematica can be used as a programming language too. Sequential,logical, selective operations were discussed in detail. He also explained some of thefile operations and left which are not essential at the beginner’s level. While discussingthe Calculus part we were told that Mathematica can do Limits, Differentiation, Inte-gration, Differential Equations and Integral transforms in very effective way with theminimum number of commands. The issue of Computational Physics was discussedin detail. He also shared with us the problems he faced while introducing the conceptof Computational Physics into the curriculum. In the end he nicely displayed withthe help of graphs that tough Physics problems can be solved with Mathematica withvery easy set of commands even if introduce a new variable. Overall the lecture wasa bit advanced and opened up new possibilities and working environment for solvingvarious physics problems. With the help of slides Input, Output statements and graphsof all the commands were shown to the participants and read out one by one for betterunderstanding.

Structure and properties of new carbon-based materials – Fullerens, graphenesand carbon nanotubes

Resource person: V.K. JindalSession review by I.S. Mangat

Prof. Jindal started his lecture stating that the aim of his talk was to introducethe concept of nanotechnology and its applications in diverse fields. Two carbonforms, diamond and graphite, are known for centuries but in the recent past someother carbon-based structures like fullerens, graphene and carbon nanotubes havebeen discovered. Prof. Jindal emphasised that nature knows how to recycle energyby using solar energy through the process of photosynthesis and with the help ofnanotechnology it is possible to have artificial photosynthesis process at commercialscale leading to the solution of the problem of energy crisis. He explained the differencebetween nanomaterials and bulk materials by saying that the size of nanomaterials varyfrom 1 nm to 100 nm. Alternatively, we can separate the nanomaterials from the bulkmaterials if the number of atoms in the structure is between 20 to 100 atoms. The physicalproperties of nanomaterials differ from bulk materials mainly in two aspects, due to thesurface effects and due to the quantum effects that change the properties like electrical

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conductivity, density of states, etc. Fullerens were discovered by Robert Curl Jr. in 1985and later single-wall and multi-wall carbon nanotubes were also discovered. Carbonnanotubes have high electrical conductivity, tensile strength and thermal conductivity.He listed the applications of carbon nanotubes in the field of energy storage, energyabsorption, molecular electronics, biomedical applications and for making fuel cellsbased on proton exchange membrane that converts energy into electrical form withoutburning, i.e. without creating any pollution. On the whole, the lecture was informativeand knowledgeable.

Calculation of band structure and phonons in materials as well as in graphenesand carbon nanotubes

Resource person: V.K. JindalSession review by Gurinder Singh

He started his lecture by mentioning that Nitrogen occurs naturally in N2 form(Triply bonded) but it is also possible to form N3, N4, N5 although for n > 5 it isdifficult to form such a molecule. These molecules change into N2 form and releaseenergy which is known as green energy. It is also possible to trap these larger Nitrogenmolecules inside carbon nanotubes. Up to 13 nitrogen atoms can be incorporatedinside carbon nanotubes. These molecules tend to be at centre and they are bonded bysingle bonds. It is also possible to incorporate Boron into the carbon nanotubes andthese changes the electronic properties. He highlighted the use of nanotechnology inelectronics, computing, cosmetics and medicines. The challenges in nanotechnologytoday are novel synthesis and large scale development. In the second part he talkedabout Band structures in solids. He gives brief review of Bloch wave function and howperiodic potential imposes condition on wave function. The graphene unit cell has twoidentical atoms. As a result its band splits into two bands and the two parts touch eachother at a particular point, so it is conducting. In carbon nanotubes unit cell is madeup of many atoms, so it is also conducting. Then he talked about the three differentstructures of single walled carbon nanotubes: Arm Chair, ZigZag and Chiral. Thestructure for these is found by varying the bond length and then calculating the energy.Energy minimum gives the correct structure. There are two different bond lengthspossible for arm chair and zigzag structure. At small distance difference between twobond lengths are prominent. Then he showed the effect of hydraulic pressure on carbonnanotubes. At a critical pressure both bond lengths are equal. For a smaller tube morepressure is required to change its shape. He mentioned SIESTA and VASP as simulationpackages to carry the theoretical studies. He showed some slides of various methodsto produce carbon nanotubes: Arc discharge method, Electric Arc discharge method.In the end he showed some TEM images of Nanotubes. In all lecture was informative,knowledgeful and resource person answered to the queries of the participants.

Basics of QGP

Resource person: M.M. AggarwalSession review by B.R. Behera

Prof. Aggarwal started with the basics of ultra relativistic heavy-ion collision. Theprimary motivation for studying Ultra relativistic heavy-ion collision is to gain an un-derstanding of the equation of state of nuclear, Hadronic and Partonic matter, commonly

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referred as nuclear matter. He started with Quantum Chromo-dynamics (QCD). QCDis nothing but the theory of the strong interaction. He introduced the quark structureof the nuclear matter. Each quark has three colures and hence introduced the coluresquantum number. Then he introduced the concept of Quark Gluon Plasma (QGP) (TheQGP at high temperature and QGP at high baryon density). At this point he introducedthe schematic phase diagram of Nuclear matter (i.e. the behavior of nuclear matter asa function of temperature and density (pressure). In the phase diagram conventionalnuclear physics is concerned primarily with the lower left hand portion of the diagramat low temperature and near normal nuclear matter density. Here, normal nuclei existsand at low excitation a liquid-gas phase transition is expected to occur. This is thefocus of the experimental study using low energy heavy-ions. At somewhat higherexcitation, nucleons are excited into baryonic resonance states along with the accompa-nying particle production and hadronic resonance formation. In relativistic heavy-ioncollision such excitation is expected to create hadronic resonance matter.

Prof. Aggarwal then focused on the six signatures of QGP in nucleus-nucleus col-lision. He also briefly described the first experiment of RHIC at Brookhaven NationalLab. It had five experiments; STAR, BRAHMS, PHOBES & PHENIX. Each experimentwas tailored to probe specific things. The direct signatures of the PGP are:

1. Strangeness enhancement: The production of the strange hadrons relative to non-strange hadrons is suppressed in hadronic reactions. This suppression increaseswith increasing strangeness content of the hadrons. In a QGP the strange quarkcontent is rapidly saturated by ss(bar) pair production in gluon-gluon interactionsresulting in an enhancement in the production of strange hadrons. Thus multi-strange baryons and strange anti-baryons are predicted to be strongly enhancedwhen QGP is formed.

2. J/Ψ suppression: J/Ψ is nothing but the bound state of charm and anti charm. Theproduction of J/Ψ particle in quark gluon plasma is predicted to be suppressedin a QGP. This is nothing but the result of Deby screening in a cc(bar) pair. Theyare initially formed in the QGP by fusion of two incident gluons. When passingthrough the medium J/Ψ is suppressed.

3. Direct Photons: Electromagnetic probes such as photons and Leptons provideinformation on the various stages of the interaction. Excess of photon productionreflects the QGP formation. At SPS the WA98 experiment looked for the directphotons.

4. High PT Particles: He also mentioned that high PT particles are also signatures ofQGP.

5. JET Quenching: A quark or gluon JET propagating through a dense mediumwill not only lose energy but will also be deflected. This effect destroyes the co-planarity of the two jets from a parton-parton scattering with the incident beamaxis. The angular deflection of the jets also results in an azimuthal asymmetry.The presence of the QGP is also predicted to enhance the emission of JET pairswith small azimuthal opening angle.

6. Elliptic Flow: It describes the azimuthal momentum space anisotropy of particleemission from non-central heavy-ion collision in a plane transverse to the beamdirection. Elliptic flow is a fundamental observation, since it directly reflects theinitial spatial anisotropy of the nuclear over lap region in the transverse plane.

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In summary Prof. Aggarwal took us to a nice journey through the world of ultra-relativistic heavy-ion collision.

Nuclear models and their applications I

Resource person: S.S. MalikSession review by Vishal Kumar

Dr. Shyam Sunder Malik started his lecture telling about the importance of Nuclear-Physics for teaching and research point of view. Then he told about the energy- pro-gram of India which stated in 1950 after independence and the applications of radio-isotopes in medical, geological, industrial fields. Dr. Malik discussed brief history ofthe development of concepts of Nuclear and Particle Physics. He told about variousdiscoveries and the phenomenon observed with a quick sight on them also mentioningthe year and names of the scientists and researchers behind them.

Some other topics covered in his talk were: extension of periodic table, observationand explanation of magnetic rotational band spectra, chiral twins, PT symmetries, x-raylaser, concept of γ-ray laser with its commercial aspects, Hallo nuclei, Hyper nuclei,introduction of quark model, discovery of electron, Plum pudding model of atom givenby J.J. Thomson, discovery of nucleus in 1908 by Rutherford and its confirmation byNiels Bohr in 1913 using spectra of Hydrogen, the discovery of neutron in 1932 by JamesChadwick, strong , electromagnetic, weak and gravitational interactions, Yukawa’smeson theory of nuclear forces given in 1935 and its confirmation by Powel in 1947 andDeutron ground state problem.

During his informative talk Dr. Malik discussed the frontline areas of research aswell as some old but important discoveries. In this way in his first lecture he preparedthe base for the second lecture in which he was going to discuss the nuclear models. Itwas a conceptual talk. He delivered his lecture in very simple language and used thenecessary mathematical steps to clear the concepts. The lecture was appreciated by theparticipants.

Nuclear models and their applications II

Resource person: S.S. MalikSession review by Ashok Kumar

The lecture by Dr. Shyam Sunder Malik was aimed on the Nuclear Models. Nuclearmodels can be divided broadly in two categories: semi-empirical models and micro-scopic models. He describe liquid drop model in very fascinating manner. Saturation,incompressibility and definite shapes are the main characteristics of the LDM which re-sembles with the liquid drop. The main difference between the liquid drop and nuclearmatter is the mean free path which is much longer in the nucleus than liquid drop due tothe Pauli exclusion Principle. He described the contribution of volume energy, surfaceenergy, Coulomb energy, asymmetric energy and pairing in the binding energy formulain very illustrated way. He also explained the use of this equation for the production ofnuclear energy. This model was successful in explaining many experimental results butwas unable to explain the spin, parity and some other properties of the nucleus so other

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nuclear models were developed with time. Then he explained the shell model devel-oped by Myers and Jenson and explained the terms used in the nuclear potential andreproduced the magic numbers using this model. He explained that without spin-orbitterms in the nuclear potential, we can not reproduce the magic numbers after 20. Thisterm is negative in the case of nuclear potential whereas it is positive in case of atomdue to Coulomb Potential. In the last he showed that how wave functions of protonand neutron can be written in a vary simple way using quark model. He calculatedthe magnetic moments of the proton and neutron using this model. He explained thedifficult concepts of nuclear theory in a very simple way and all the participants enjoyedhis lecture.

Standard Model I

Resource person: Manmohan GuptaSession review by Sarvpreet Kaur

Prof. Manmohan Gupta explained that, the Standard Model (SM) is the simpletheory which explains the fundamental particles (FP) of the universe and the interactionbetween them. According to him there is no standard definition of fundamental particle.But according to a formal definition FP is that which further cannot be divided into itsconstituent particle. Explaining the SM , he told us that quarks, leptons and baryons(force carrier) are the fundamental Particles(FP) of matter and both lepton and quarkscome in pairs and they are 12 in numbers and always exist with their corresponding antiparticles. Then he talked about their certain characteristics like charge (quarks havefractional charge), spin (leptons and quarks=1, bosons=2) and mass. Talking aboutmasses he told us that there are two types of masses known as current quark masswhich refers to the mass of a quark itself and constituent quark mass which refers tothe current quark mass +mass of gluon particle field surrounding the quark.

He also made clear that earlier quarks were not observed they enter into the pictureonly as a parameter in the theoretical calculations. Deep inelastic scattering experimentsand a range of low energy phenomenon like mass spectrometry etc gave the convincingevidence for the existence of the quarks. Also he explained that how three generations ofthe matter(fermions) exist. Then he talked about the different interactions between theFP. According to SM there are only three kinds of interactions take place, electromagneticinteraction, weak interaction and strong interaction. Gravitational interaction is ignoredin this model because at atomic and sub atomic scale gravitational force does not playa significant role.

He told us that all the three interactions occur by exchange of particle, called bosons(spin=1). They are also called gauge bosons.

1. The e.m interactions are explained by theory called Quantum electrodynamics orrelative quantum field theory. These interactions take place between the chargedparticle by exchange of photon of light. Photon has zero rest mass. So e.m forcesare infinite range forces. He also told us that the exchange photons are also calledvirtual photons. He also explained the concept of quantum fluctuation. Accordingto which photon obeys the uncertainty principle, which allows the short termviolation of energy conservation. He explained that in QED till date there is noviolation and this theory is able to explain the Rutherford scattering experiments

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and tunneling of electrons. This theory also permits the term(using Feynmandiagram) *Self energy contribution,*Vacuum polarization, *Vertex correction. Hetold us that these factors are seen and observed in case of Lamb Shift.

2. Weak Interaction; Resource person explained that the weak interactions takeplace via exchange of bosons W± and Z0. These particles have definite massso they are short range force. The neutrinos are the consequences of the weakinteractions. Till now there are only three neutrinos. Talking about neutrinos hetold us that according to SM neutrinos are mass less particles. However severalexperiment proved that neutrinos oscillate between their flavour state, whichcould not happen if all were massless.

3. Strong Forces/interactions: Talking about strong interactions he told us that stronginteraction occurs between quarks and here the exchange particles are gluons. Thetheory which explained the strong interactions is called QCD (quantum chromodynamics). This theory also give the two peculiar properties: confinement (forcebetween the quarks does not diminish as they are separated and it dominatesat low energy scales) and asymptotic freedom (at very high energy quarks andgluons interact very weekly).

During his lecture many times he explained that the theory of Standard model isnot a complete theory. According to SM there are three neutrinos , but there is strongevidence that the number is not three He also told us that detectors at CERN, Fermilaband LHC are looking for Higgs bosons which will either explain the standard model orforce us to readjust our conception of matter.

The resource person was well versed with his subject and his lecture was wellprepared and well delivered. He explained all the features and drawback of StandardModel in a very simple manner.

Stellar evolution and nucleosynthesis

Resource person: Sandeep SahijpalSession review by Lokendra Kumar Borker

Dr. Sahijpal started his lecture with introduction to SUN, EARTH and MOON. Hesaid sun is a purely geseous body. The formation of sun was 4.5 billion year ago. Thesurface of the sun consists of hydrogen 74%, helium 24% of its mass and trace quantitiesof other elements. The sun emits radio waves, x-rays and energetic particles in additionto visible light.

Solar activity is thought to have played a large role in the formation and evolutionof the solar system solar activity changes the structure of Earth’s outer atmosphere. Thecorona is the extended outer atmosphere of the sun, which is much larger in volumethan the sun itself. Energy is produced by nuclear fusion through a series of steps calledthe P.P chain. The rate of nuclear fusion depends strongly on density and temperature.

Dr. Sahijpal explained about Red giant starts, there are different types of Red giantstars RGB, Horizontal Branch and AGB. The formation of elements hydrogen andhelium created by Big-Bang and all other elements created by fusion processes instarts. These stars eventually explode as supernovae. The most important reactions in

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stellar nucleosynthesis are hydrogen burning, helium burning and burning of heavierelements.

Finally Dr. Sahijpal also explained CNO Cycle, birth and formations of the stars,with the help of various slides. Lecture was interesting and informative and resourceperson was very dynamic also.

Computer lab

Resource person: Vipin BhatnagarSession review by P.A. Savale

Dr. Vipin Bhatnagar first introduced about the history of the Computer LAB ofDeptt. of Physic PU, Chandigarh. He told that, this lab and all the computers andother accessories are of 7 years old. This lab was started in 2003 for computer diplomacourse. This computer lab has 23 computers. Then he told that the operating systemLinux is used in most of the computers. Linux is an open operating system, and it isavailable free of cost. He described about the network in which this lab is connectedto the Deptt. of physics and PU, university campus. He told that this lab is connectedwith Deptt. of physics through UTP with 10 mbps and Dept. of physics is connectedto PU, campus LAN through fiber cable with 155 Mbps and 1 Gbps. The PU, campusLAN is connected to computer centre of the PU.

In his talk, he gave some important information about computers. Viruses will notaffect the computer systems and the systems will not be disturbed and all programmesare safe in this network. Internet facilities are free to all. Timing of Computer lab isfrom 10.00 am to 5.00 pm, every working day. All computer machines are identified bytheir IP numbers.

In the session, he also solved the difficulties of the participants while working onthe computers. However, the talk was very brief still it was informative.

Basic electronics – circuit theory

Resource person: D. MehtaSession review by J.S. Shahi

As the topic was very basic, Dr. Devinder Mehta started his talk by discussing I-Vcharacteristics of simplest component i.e. resistance and subsequently explained theseries and parallel combinations graphically. Further I-V characteristics of differentdevices such as diode, an ideal voltage source, ideal current source, current and voltagecontrol devices, circuit under open and short circuit condition etc. were also explained.Dr. Mehta very nicely used the graphical method to explain the working of a Zenerdiode especially when a combination of the two head to head series diodes are usedas clipping circuit. The parallel combination of two diodes along with two referencevoltage sources working as limiting/clipping circuit was also discussed.

In the next part of his lecture Dr. Mehta introduced the basic concepts of twoport circuit analysis using the matrix notations by explaining hybrid parameters andtransmission matrices for different combinations such as series, parallel and hybrid. Theexample of a transformer was used to put his point through by giving its transmission

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matrix and further extending it for additional networks. The use of transformer as amatching device was also mentioned. That was followed by a discussion on a generalform of circuit containing resistances, capacitors, inductances and voltage / currentsources. The circuit equations were derived and use of Laplace transformations wassuggested for the calculation of their solution. In the process Dr. Mehta gave a verysimple way to redraw the total circuit in a very simple form using different terms of thecircuit equation. The circuit can easily be re-drawn by simply inspecting the circuit andconverting various components into combinations of resistances and voltage / currentsources and then solving the same by the use of transmission matrix. In the last partthe importance of transfer function was nicely explained using an example of a circuitcontaining sinusoidal voltage source.

Dr. Mehta very nicely introduced the basic network theory in a very interesting wayusing good examples. Use of matrix notation was emphasized rather than using longcomplicated equations. Overall the lecture was very interesting and informative.

GUTs

Resource person: C.S. AulakhSession review by Rohan Kaushal

In the beginning of this interesting lecture Prof. Aulakh told the participants thathe started working on super symmetries around 30 years back and was still workingin the same field. He drew a historical picture of the particle physics in ancient worldincluding India. He mentioned that the concept of atoms and elements was veryold in human civilization and named an Indian atomist Kanada who lived during600 B.C. He reminded the participants about the five basic elements according to ourancient wisdom. He showed graphically the variations in the number of elementaryparticles with the passage of time and how the number increased rapidly in the presentday scenario with the development of high energy particle accelerators like the LargeHadron Collider (LHC).

Coming to the Quantum Electrodynamics (QED) Dr. Aulakh mentioned that itsbasic paradigm was the marriage of Electrodynamics and (Relativistic) Quantum fieldtheory. He talked about Feynman, Schwinger, Tomonage, Dyson, Salam, Maxwelland the beginning of unification. He told the participants how the fact, that someequations were covariant with respect to the Lorentz transformations but not withrespect to the Galilean transformations, led to the development of special theory ofrelativity. He explained the interactions of a charged particle with the electromagneticfield and mentioned that when the field becomes strong it may lead to the creation ofa particle and anti particle pair (e.g. electron and positron). He then talked about theguage symmetry. Answering the queries of one of the participants the resource personexplained the coupling constant and its behaviour graphically and in a very interestingmanner and also talked about the charge renormalization. Answering another query hementioned that infinite coupling constant was not a problem as it would be significantat very high energies of the order of 10200 Gev. He started explaining the standardmodel with a brief mention of its history, discovery of quarks and Fermi theory. Heexplained guage group and gauge theory of weak interactions by Weinberg and Salam.He talked about the fundamental forces and mentioned that the gauge particle for thegravitational force i.e. graviton had spin 2, where as that of other forces were having

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spin 1. He also talked about Higg’s boson. Then he briefly explained some peculiaritiesof the standard model in a simple manner and told that the quarks were slaves at lowenergies but free at high energies. He also explained how people did not bother aboutthe right handed neutrino in the beginning.

Prof. Aulakh informed the participants about the experimental verifications throughparticle accelerators like LEP I, LEP II, KEK, DESY etc and the neutrino telescopeslike Super Kamiokande, SNO etc. He then explained the grand unification in a veryinteresting manner and told that guage bosons were so massive that as yet they areunseen at lower energies. He then explained the Pati-Salam model and mentionedabout the friendship of his Ph.D. advisor Dr. Mohapatra with Pati and Salam. He talkedabout his work with Salam during his post doctoral fellowship at ICTP, Italy. He alsomentioned some other models like Georgi Minskowskiand Gerogi Glashow models.Discussing the super symmetry he explained the hierarchy problem and informed thatthe super symmetry model was the standard model combined with its xerox and alsomentioned its gauge particles.

The lecture was full of information. The language was simple. Interaction of theresource person with the participants was good. He also amused the participantsthrough humorous examples in between the lecture and also mentioned since howlong he had been working in this field which involved such tedious mathematicalformulation.

Physics lab

Resource person: S.K. TripathiSession review by Manohar Lal

Participants of refresher course in physics visited M.Sc.II lab under the able super-vision of Prof. S.K.Tripathi. He showed the participants, a list of 19 experiments whichare performed in the lab. Then he explained the working of many experimental setups.Each experiment is performed by the group of two or three students. Then, he showedthe lab reports submitted by the M.Sc.II students. Then, he started discussing exper-imental set up one by one. In bubble chamber experiment, trajectories of the particlewere shown to the participants. Then, he explained Hall effect set up and explainedthe method to calculate Hall coefficient. Later, we moved to x-ray diffraction experi-ment which was told to be a very old setup and is still in working condition. The, heexplained electronic spic resonance apparatus, β-ray spectrometer, Compton scatteringand microwave setup. We were also told about the assembly programming and parallelport. Curie temperature kit was discussed in detail. The queries of participants wereanswered in an effective way by the resource person.

Overall this was a very good experience for those participants who had not seensome of the setups before. Participants appreciated the way in which the lab wasmaintained. Some participants took the idea to have some experimental setup in thelabs of institution. Most of the experimental setup were exclusive and of such standardso that the were able to provide good experimental knowledge to postgraduate students.

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Introduction on recent advances in nuclear physics

Resource person: Ranjan BhowmikSession review by I.S. Mangat

Dr. Ranjan Bhowmik started his talk with a slide displaying pictures of Nobel Prizewinners in the field of nuclear physics and he mentioned that although the history ofnuclear physics is about 100 years old but many challenging questions are yet to be an-swered in the field of low-energy nuclear physics and it would require next-generationaccelerators that would be operational in the next decade. He briefly discussed thefour fundamental interactions of nature, i.e., gravitational, electromagnetic, weak andstrong interactions. He said that nuclear physics is a phenomenological theory anda good theory is the one that has predicting powers. He listed the basic questionsin nuclear physics, like exploring the new exotic phenomena, impacts in astrophysicsand search for matter at extremely high density. He discussed the structure of nucleusconsisting of protons and neutrons in a high-density (1014 g cm−3) state and havingbinding energies (≈ 8 MeV). The effective interaction in a nucleus has both central andtensor components. To explain the effective interaction in the nucleus he introduced theconcept of mean field that is sensitive to the strength and range of effective interaction.The basic requirement of mean field is that it should be able to produce the ground-stateproperties of the nucleus, like mass, spin, binding energy, parity, etc. He emphasisedthat the study of nuclear excited states provides a tool to get information about nuclearstructure. The excited states of nucleus are produced by fusion of two light nuclei,fission of heavy nucleus and reaction between high-energy projectiles (> 50 MeV) andthe target with the help of accelerators.

Dr. Bhowmik then discussed some special nuclei, like 12Be, 11Li and 19C, whichare called halo nuclei as these nuclei have an extended tail of low-density neutrondistribution and abnormally large radii. He concluded his talk by saying that theproduction of superheavy elements is a difficult task as they have extremely low cross-section and their chemistry is also unknown. The participants enjoyed this lecture as itwas interesting and informative.

Exotic nuclear shapes

Resource person: Ranjan BhowmikSession review by Ashok Kumar

Dr. R.K. Bhowmik explained the various nuclear structure phenomena consideringthe different shapes of the nucleus. In nearly spherical nuclei, the level structure can beexplained on the basis of the vibrational motion of the nucleus. As we move towardsthe mid-shell, the nucleus deviates from the spherical shape and becomes deformed.He showed the different exotic shapes of the nuclei from simple axially symmetricto octahedral shapes. He showed that how the nucleus takes different shapes likeprolate, oblate, triaxial, tetrahedral, octahedral etc. and explained these shapes on thebasis of symmetry breaking. When rotational symmetry breaks, the nucleus becomesaxially deformed. And J does not behave as a good quantum number. When axialsymmetry breaks, nucleus becomes triaxial , K mixing takes place and wobbling motionarises. He explained it taking the example of 163Lu which is the best wobbler. Heexplained the magnetic rotation, anti-magnetic rotation and chirality in the nucleus

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and discussed the signatures. He also discussed the Tetrahedral and Octahedral shapesof the nuclei. Then he explained the experimental techniques to populate the neutronrich and neutron deficient nuclei using the transfer/deep inelastic scattering and fusionreactions respectively. He also discussed the Indian National Gamma Array (INGA)having the 15 Clover detectors.

His talk was very informative and useful for the participants.

World of dizzy nuclei

Resource person: Ranjan BhowmikSession review by Jyotsna

Prof. Bhowmik started his talk with discussing various rotations in the universe.He told us that the rate of rotation per second increases with decrease in size of theobjects. On a scale, galaxy clusters are the largest object rotating very slowly. Thencomes Pulsars rotating with a few rotations per second. Mechanical tools with 104

rotations/s then molecules with 1014 revolutions/sec and at the other end of the scaleare nuclei whose dimensions are smaller by a factor of 20,000 compared to a molecule.Therefore, they rotate much faster at the rate of 1020 revolutions per second emitting anumber of γ rays.

He then discussed the rotation of Quantum mechanical systems and comparedthem with classical system rotations. Classically, rotation is about symmetry axis butquantum mechanically rotation is possible about a direction perpendicular to the sym-metry axis. Then he discussed the excitation modes of a molecule that are rotational,vibrational and single particle excitation modes. For nuclei, different modes have com-parable excitation energies of the order of MeV which make overall spectrum complexwhich can be simplified by the presence of certain symmetries. Molecules can alsohave complex rotation spectra if we relax the symmetry constraints. He illustrated theconcept of rotational spectrum by taking example of methyl acetate. He then showedus the experimental setup to obtain nuclei at high spin by shooting high energy heavyions at a target.

Also, he made us aware of the progress in γ spectroscopy. In 1950, NaI detectorswith resolution 50Kev were used. In 1962, Li drifted Ge detectors with resolution 6 KeV.Then, in 1970 γ-γ coincidence detectors with 2Kev resolution and in 1990 large multidetectors were used. He introduced the concept of magnetic rotation in nuclei. Towardsthe end of his talk he told us about the origin and meaning of the term ‘chirality’. Itoriginated from the greek word ‘Chaire’ which meant hand. Thus, chirality standsfor handedness. He explained chirality using a complex molecule. He then invitedqueries regarding the topic and answered them. In all the lecture was informative andinteresting.

Visit to TBRL

Session review by Shaminder Sandhu

All the participants assembled in front of Department of Physics at 9.30 am andboarded the bus for TBRL. Participants enjoyed playing antakshri on wa to TBRL. Wereached main gate at 10.30 am and rushed to zone I, where a video named as ‘Journey

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to excellence’ having vital information about TBRL, facilities and its contribution tovarious fields was displayed. It was informed, TBRL is one of the 52 laboratories ofthe Defence Research and Development Organisation (DRDO). TBRL was envisagedin 1961 as a modern armament research laboratory under the Department of DefenceResearch & Development. It is spread over an area of 5000 acres is located at Ramgarh inHaryana. It became fully operational in 1967 and was formally inaugurated in January1968 by the then Defence Minister S. Sawarn Singh. This laboratory has become one ofthe major DRDO labs in the field of armament studies.

TBRL conducts basic and applied research in the fields of high explosives, detonicsand shock waves. It is also involved in evolving data and design parameters for newarmaments, as well as assessing the terminal effects of ammunition.

Other areas of work include:

• Performance of armour defeating projectiles and immunity profiles

• Studies of ground shock, blast damage, fragmentation and lethality

• Preparation of safety templates for various weapons

• Studies of underwater detonics and pressure wave propagation

• Explosive forming, cladding and welding.

• Detonation dynamics of high explosives.

TBRL is responsible for the development of Explosive lenses for India’s Nuclearweapons. These lenses were used on the Nuclear devices detonated in Pokhran-Iand Pokhran-II. Apart from this, TBRLalso develops explosives-based products forconventional military and civilian use. TBRL has developed a Non-lethal Riot controlPlastic bullets for use by paramilitary forces and police.

The particiapants visited the various zones of the TBRL. After the presentation allthe participants moved to Small arm testing Lab. Mrs. Biswas elaborated the expertiseand specialised facilities for ballistic evaluation of bullet proof panels/helmets againstvarious small arms ammunitions. Participants also got the first hand experienced of thefiring being done in this chamber for testing purpose. She also explained and shown tothe participants how the testing of arms is done.

After this we moved Gas Gun Control room. All the participants were welcomedby Dr. Manjit singh and participants enjoyed the presentation on On high strain ratestudies and Ballistic Evaluation. by Mr. Prince Sharma along with tea and snacks. Thislab is useful to study the impact between bodies moving with relative speed of the orderof 0.5 to 8.5 km/s and hence its useful in the exploration of outer space and radioactivematerials.

Our next stop was at Blast and DamageStudies, where Ms. Sakshi Arora beautifullypresented the work and facilities of their unit to study the effect of Blast, mines etc. onArmy boots (Shoes), bulletproof vehicles. She became nostalgic & emotional to see herteacher Dr. Sunita Srivastava.

Finally we reached at Shock & Detonics unit, where Dr. Manjit Singh along with hisgroup again interacted with the participants & explained the use of detonator to blastthe RDX, properties and different types RDX materials. The use of very high resolution

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camera was also explained by him. Finally approximately 1 kg RDX was detonated togive first hand experience of whole setup and working of the equipments.

On way back to Panjab University, all the participants paid obeisance at GurdwaraNadha Sahab and enjoyed Langar.

At TBRL, we experienced how the simple laws of Physics were being used practicallyfor useful analysis. All the staff members of TBRL were very cooperative. We thankDr. Manjit Singh for wonderful hospitality and concern. This visit had a deep impacton us. This was a lifetime experience for all of us.

Standard Model II

Resource person: Manmohan GuptaSession review by Baljinder Kaur

Prof. Gupta started his talk with the introduction to quantum field theory whichinvolves need to write Lagrangian, identifying fields and use Lagrangian equation tofind field equations and to find the physical content in it. Then, the contravariant andcovariant notations were discussed. First kind of global gauge invariance was then ex-plained which involves that the conservation of additive quantum number correspondsto global gauge invariance by explaining the suitable examples. Talking about the localgauge invariance, he explained that Lagrangian is not invariant under the local gaugetransformations but it can be made invariant for field called gauge field and deriva-tive as covariant derivative is defined. Then he switched over to non-abelian gaugetransformations where SU(2) group was considered and again Lagrangian invariantunder infinite transformation can be constructed from where isospin conservation canbe obtained. The next topic of the talk was related to spontaneous symmetry break-ing SSB is helpful in solving the discrepancy that gauge fields leads to masslessnessof particles but actually these are massive, so the focus was to find that there is masswith gauge field and Lagrangian can be solved easily. The SSB was explained verybeautifully by using the example of Gauss’s law and explaining the limitation of theassumption involved. Then by taking the example of vibration in a clamped rod, itwas very clear to see that the symmetry of vibrations remained unchanged till somecritical value of applied force, but beyond that force the symmetry is broken as systemattained another ground state even with very small perturbation and the implicationof SSB results in two types of interacting scalar particles in Quantum field theory, onecorresponds to the massive particles and others as massless. In the last part of thetalk, the Goldstone theorem and theorem of t’Hooft were discussed and there comesan important theory, Yang Mill’s theory, which states that although symmetry breakingcontains Bosons but remains renormalizable. Also, Higg’s mechanism which resultsin massive photons due to symmetry breaking and standard model was included andlatest status of Higg’s boson or God’s particle which is yet to be discovered were theconcluding remarks. The overall talk was very informative.

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Computer simulations

Resource person: Tankeshwar KumarSession review by Gurinder Singh

He started his lecture by giving the meaning of Computer Simulation. He definedit to be a technique to represent real world by a computer program. Simulations arenecessary in today life because it provides greater flexibility than would otherwisebe available. He highlighted the use of computer simulations in physics, chemistry,biology, human systems in economics, psychology and social sciences. Computer Sim-ulations can be used to study physical systems consisting of many atoms or molecules,galaxies, nanomaterials and clusters. In each of the case position and momentum ofthe particle has to be found over a span of time. Molecular modelling is divided intotwo categories: Statistical and Deterministic. In statistical modelling one uses law ofstatistics to calculate the position and momentum whereas in deterministic approachone uses equations of motion to find position and velocity of the particles. In LangevinDynamics approach one uses both of the methods. In statistical method he describedthe Monte Carlo method. He calculated the value of π from area under curve by usingthe Monte Carlo method. He gave various steps to explain the Monte Carlo methodon physical systems. In the first step various inputs like density, number of particles,temperature and positions of the particles are assigned. Then boundary conditions areapplied. Particles are then moved in a random manner till the energy is minimized.When minimum energy state is achieved than equilibrium structure of the system understudy is obtained. Then various parameters dependent on position could be calculated.In molecular dynamic simulation technique position and velocities of the particles areobtained by using Newton’s equations and the trajectory is generated by using Verletalgorithm. There are some limitations of simulations: First limitation is that small sys-tem can never reach the equilibrium state. Second limitation is that temperature is notproperly defined, particle in one region would be solid like and in the other they wouldbe in the gas state. He also mentioned that temperature for each time step should beconstant and the time step size should not be too large or small. In all lecture was goodand knowledgeful. Resource person was able to generate the interest of the participantsin the field of computer simulations.

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Some pearls of wisdom collected from various talks

• Computer was designed first and microprocessor later.

• Contents of theory can never be more than the contents of assumptions. As thedomain of knowledge increases, we may have to revive a theory.

• Syllabus is the only link between the teacher, the student and the examiner.

• A teacher is not for covering the syllabus, but to uncover it.

• A teacher should ask himself whether he is teaching science in a scientific way.

• Can you think of a problem for which the time required for solving is independentof its size? Here is one: to determine whether a given number is even or odd.

• Present-day cryptography, based on the fact that we cannot factor a very largenumber on computer, will be shattered by quantum computer, which can dofactorisation in polynomial time instead of exponential time.

• Ultimately the Sun will become a red giant and will eat up the Earth.

• A single-sentence description of the standard model:It is a chiral SU(3) × SU(2) ×U(1) spontaneously broken nonabelian gauge theory.

• First evidence of physics beyond standard model is the discovery of neutrinomasses.

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Course report (43-page pdf)

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