T8 B6 FAA HQ Daniel (Darrel) Smith Fdr- 7-13-04 MFR and Email- NOIWON 872
The Energy in our Universe Dr. Darrel Smith Department of Physics.
30
The Energy in our Universe Dr. Darrel Smith Department of Physics
Transcript of The Energy in our Universe Dr. Darrel Smith Department of Physics.
The Energy in our Universe
Dr. Darrel SmithDepartment of Physics
Sources of Energy in the Universe
1. Matter a. Gravity b. Fusion
2. Photons -- CMB 2.7 deg.
3. Neutrinos -- 1.7 deg.
4. Dark Matter
5. Dark Energy
Our SunHow much power is generated by the sun?
a) 200 megawatts 2 x 108 watts
b) 5,000 terawatts 5 x 1015 watts
c) 2,500 exawatts 2.5 x 1021 watts
d) 380,000,000 exawatts 3.8 x 1026 watts
The power is called the Luminosity (watts)
How does it make that energy?
Fusion of hydrogen p p p n e+ ne
T + D He4 + n
Surface Temperaturevs.
Core Temperature
What does it cost to make all this sunshine?
In other words, what does this do to the mass of the sun?
a) Mass is converted to energy
b) Power
c) 1% of the solar mass 100 billion years to burn off
Energy from type 1a Supernovae
Type 1a Supernovaea)Releases a uniform amount of
energy 1-2 x 1044 joules
b)Luminosity ~ 5 billion times greater than the sun
c) ~10 billion stars in our Milky Way galaxy
Formation of a supernovae
Remnants of Supernovae
Crab Nebula (1054 AD)
Power output = 5 x 1031 W = 130,000 Lo
A pulsar in the core providesthe energy.
Pulsar is a highly magnetizedrotating neutron star.
Rotational K.E. is decreasing.
Supernovae observed
1054 AD Observed by the Chinese
Observed by Anasazisin Chaco Canyon
6500 light years away
1987A Supernova in the LargeMagellanic Cloud.
Supernovae Summary
1. Energy comes from where?
2. Where does the energy go?
3. Source of heavy elements
4. Indicator of Dark Energy
Particle Astrophysics
Big Bang Cosmology
How do we know what the early universe was like?
The LHC at CERN
Big Bang Cosmology
From t=0 through today
How do we know this? Particle Astrophysics
Particle Astrophysics
The Tevatron at Fermilab
The Large Hadron Collider (LHC)
Geneva, Switzerland
Standard ModelThe physicists equivalent to the periodic table.
Unifies QCD with EW interactions into a single structure.
It does not include gravity.
It is a quantum field theory that is consistent with quantum mechanics and special relativity.
Standard Model
q = +2/3 e
q = -1/3 e
q = 0 e
q = -1 e
Particles have masses
Mp = 0.938 Gev/c2
Big Bang Cosmology
What is the Higgs Particle?
So, how do particle acquire mass?
Through their interaction with the Higgs field.
W+
W-
Zo
How is the Higgs formed?
• The fusion of one quark from each proton.
• Coming together at high energy.
A simulated event in the Atlas detector
How is the Higgs formed?
•The fusion of one gluon from each proton.•Coming together at high energy.
A simulated event in the Atlas detector
Why such a big machine?
We need high energies to make massive particles.
E = mc2
Why such small distances?
We need to put that energy in a small volume to make a high energy density.
l = h/p
Mass vs. Size
Mass is not proptional to size.
Masses of the W and Z particles
MW = 82 GeV/c2
Mz = 90 GeV/c2
Mproton = 0.928 GeV/c2
Galactic Rotation Curves
Velocity = constant (??)
Bulge + Disk + Dark Halo
Where’s the “missing mass” ?
Could it be neutrinos?
Could it be black holes?
Dark EnergyDifferent from “dark matter”
It causes the universe to expand (i.e., to accelerate outward.
How is this observed?
http://imagine.gsfc.nasa.gov/docs/science/mysteries_l1/dark_energy.html
Dark EnergyChanges in the rate of expansion
The more shallow the curve, the faster the rate of expansion.
Dark EnergyMost of the energy in the universe today is “dark energy.”
Next, comes “dark matter.”
Only 4% of the universe is made of “regular matter.”Neutrons, Protons, electrons, photons, & neutrinos.
Exotic PropulsionHow can we travel through our galaxy?
Matter-Antimatter propulsion
Nuclear-Thermal Propulsion
Faster-than-light propulsion (??)
