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Quantum Computing- Software

Presentation Overview

My presentation basically looks over the basic of how a quantum computer works, with special

detail into how a qubit operates and some uses of quantum computers in terms of software. The

PowerPoint is meant to be a complementary part of my presentation with it helping the audience

understand extra information about my speech by the use of diagrams and dot points. The

PowerPoint has been optimized so that it does not repeat what I have said in my speech too much,

but acts as extra information to limit redundancy.

I start of my speech by talking about how a qubit works the equivalent of a bit in a classical

computer. I attempt to make the explanation as simple as possible so that the audience can

understand what is in reality an extremely hard concept. I add to the speech by showing the formula

of how a qubit works in the PowerPoint. In the second slide, a representation of a qubit when

compared to a bit is also shown to help the audience visualise what a qubit looks like in reference to

a bit.

It is necessary to talk about the qubit as an essential part of the quantum computer as it is one of

the main things that separate quantum computers from normal computers. I then explain how qubit

will change the way software is written, as the software which actually runs the code will have to

take into account that a qubit has many more states than a bit, which only has two. I then explain

the effect this will have on the software community with new types of developers arising, those who

can code for quantum computers.

I then talk about the main topic of the actual software which can utilise the enormous speeds of the

quantum computers and put them to good use. I talk about how one potential use for breaking

encryption. I explain that Shors theorem can be used to crack encryption that uses integer

factorisation and how it requires the computers to run at polynomial time to be able to complete

this. Classical computers cannot do this and then I explain that quantum computers can easily run in

this state because of their enhanced speed.

I then explain another use of quantum computers is that they can be used to simulate complex

chemical and physical processes that cannot actually be conducted and cannot be simulated by

classical computers. Lastly I explain another way that they can be used is as an alternative to brute

password cracking software by using another theorem; Grovers theorem. I explain how it is a much

better alternative to brute password cracking as it is a much quicker method through quadratic

speedup allowing it to go through more possibilities faster as well as being able to skip some

possibilities depending on the rejection of the passwords given. I attempt to summarise the topics

above as well as I can in my PowerPoint so that anyone not understanding the speech can just read

of the PowerPoint, as well as the fact that it adds more reinforcement to my presentation.

I then end my speech and pass onto the next person?

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Another software use of quantum computers is them being used as an alternative to brute force

password cracking software. They can be used to crack passwords if it follows the following rules.

For these properties the time it takes a quantum computers to crack the password is proportionate

to the square root of the number of inputs. This is a much better alternative to the previous brute

cracking software, as it utilises Grovers algorithm to obtain a quadratic speed up over a brute force

password cracking software. O(N1/2

)

1. The only way to solve it is to guess answers repeatedly and check them,

2. The number of possible answers to check is the same as the number of inputs,

3. Every possible answer takes the same amount of time to check, and

4. There are no clues about which answers might be better: generating possibilities randomly is

just as good as checking them in some special order.