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Superposition

Is superposition actually something over a wave to do? I'm trying to get my head around quantum computers and it's talking about quantum superposition which I'm struggling to understand
Original post by isiaiah d
Is superposition actually something over a wave to do? I'm trying to get my head around quantum computers and it's talking about quantum superposition which I'm struggling to understand



You can think quantum superposition in analogy to the wave superposition. But don’t over-rely on it to “understand” quantum superposition.

Be more specific on what you don’t understand about quantum computers and quantum superposition.
Reply 2
Original post by Eimmanuel
You can think quantum superposition in analogy to the wave superposition. But don’t over-rely on it to “understand” quantum superposition.

Be more specific on what you don’t understand about quantum computers and quantum superposition.


Thanks. Do you know of anywhere I can learn more about quantum computing, I am trying to apply it to cyber security. I am new to computers so Imkind of struggling to understand how it all works.

From what I understand atoms can be excited(1) or de-excited(0) but why then can qubits take values from 0 to 1. Or am I completely misunderstanding this?
Original post by isiaiah d
Thanks. Do you know of anywhere I can learn more about quantum computing, I am trying to apply it to cyber security. I am new to computers so Imkind of struggling to understand how it all works.

From what I understand atoms can be excited(1) or de-excited(0) but why then can qubits take values from 0 to 1. Or am I completely misunderstanding this?


What is your level of study?
Reply 4
Original post by Eimmanuel
What is your level of study?


When it comes to computer science nothing (pre-GCSE) I am learning Python and am a decent level at that.

I have completed A-Level (further) Mathematics and Physics though.

I am applying to a cyber security role that doesn't require much previous experience just an interest I can express and a plan on how I am going to develop this interest into a skill during uni
Original post by isiaiah d
When it comes to computer science nothing (pre-GCSE) I am learning Python and am a decent level at that.

I have completed A-Level (further) Mathematics and Physics though.

I am applying to a cyber security role that doesn't require much previous experience just an interest I can express and a plan on how I am going to develop this interest into a skill during uni


Before studying quantum computing, you should have knowledge of introduction of quantum mechanics. You just need the formalism of quantum mechanics.

https://www.youtube.com/watch?v=lZ3bPUKo5zc&list=PLUl4u3cNGP61-9PEhRognw5vryrSEVLPr
The above set of video lectures would give you pretty solid foundation.

https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-spring-2013/

Original post by isiaiah d
Thanks. Do you know of anywhere I can learn more about quantum computing, I am trying to apply it to cyber security. I am new to computers so Imkind of struggling to understand how it all works.

From what I understand atoms can be excited(1) or de-excited(0) but why then can qubits take values from 0 to 1. Or am I completely misunderstanding this?


You may want to purchase a book on quantum computing for reference after you have study introduction to quantum mechanics.
https://physicstoday.scitation.org/doi/10.1063/PT.3.1442

Original post by isiaiah d
…From what I understand atoms can be excited(1) or de-excited(0) but why then can qubits take values from 0 to 1. Or am I completely misunderstanding this?


Qubit can be in a quantum superposition of the state |0> and |1> simultaneously.


|qubit> = a |0> + b |1>


where a and b can be complex coefficients.

Qubit doesn’t really take the values from 0 to 1.

Qubit is very different from classical bit in computer science because of quantum mechanics.

Quantum superposition means a linear combination of the quantum state |0> and |1> simultaneously. But we cannot say for sure the state of the quantum system until we make a measurement on the quantum system.
Reply 6
Original post by Eimmanuel
Before studying quantum computing, you should have knowledge of introduction of quantum mechanics. You just need the formalism of quantum mechanics.

https://www.youtube.com/watch?v=lZ3bPUKo5zc&list=PLUl4u3cNGP61-9PEhRognw5vryrSEVLPr
The above set of video lectures would give you pretty solid foundation.

https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-spring-2013/



You may want to purchase a book on quantum computing for reference after you have study introduction to quantum mechanics.
https://physicstoday.scitation.org/doi/10.1063/PT.3.1442



Qubit can be in a quantum superposition of the state |0> and |1> simultaneously.



|qubit> = a |0> + b |1>



where a and b can be complex coefficients.

Qubit doesn’t really take the values from 0 to 1.

Qubit is very different from classical bit in computer science because of quantum mechanics.

Quantum superposition means a linear combination of the quantum state |0> and |1> simultaneously. But we cannot say for sure the state of the quantum system until we make a measurement on the quantum system.

Thanks for this, I think I will start with the quantum mechanics and speak about that in the interview as well, to show commitment to learning.

Thanks for the explanation as well!
Original post by isiaiah d
Before studying quantum computing, you should have knowledge of introduction of quantum mechanics. You just need the formalism of quantum mechanics.

https://www.youtube.com/watch?v=lZ3bPUKo5zc&list=PLUl4u3cNGP61-9PEhRognw5vryrSEVLPr
The above set of video lectures would give you pretty solid foundation.

https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-spring-2013/



You may want to purchase a book on quantum computing for reference after you have study introduction to quantum mechanics.
https://physicstoday.scitation.org/doi/10.1063/PT.3.1442



Qubit can be in a quantum superposition of the state |0> and |1> simultaneously.






|qubit> = a |0> + b |1>







where a and b can be complex coefficients.

Qubit doesn’t really take the values from 0 to 1.

Qubit is very different from classical bit in computer science because of quantum mechanics.

Quantum superposition means a linear combination of the quantum state |0> and |1> simultaneously. But we cannot say for sure the state of the quantum system until we make a measurement on the quantum system.


Thanks for this, I think I will start with the quantum mechanics and speak about that in the interview as well, to show commitment to learning.

Thanks for the explanation as well!

I would not suggest saying such things to show your commitment. A plan without action means nothing.
IMO, it is what you have done that shown your commitment.


How does quantum computing apply to cyber security? This is a big question. You may want to research on this topic and narrow down to one small area. You should try to find out any researchers in the university that you are applying to are doing such research.

If you want to have an overview on Quantum mechanics in an hour without going through all the mathematics, you can look for a book known QUANTUM PHYSICS IN MINUTES by Gemma Lavender. https://www.amazon.com/Quantum-Physics-Minutes-Gemma-Lavender-ebook/dp/B01MFBP1V6
Reply 8
Original post by Eimmanuel
I would not suggest saying such things to show your commitment. A plan without action means nothing.
IMO, it is what you have done that shown your commitment.


How does quantum computing apply to cyber security? This is a big question. You may want to research on this topic and narrow down to one small area. You should try to find out any researchers in the university that you are applying to are doing such research.

If you want to have an overview on Quantum mechanics in an hour without going through all the mathematics, you can look for a book known QUANTUM PHYSICS IN MINUTES by Gemma Lavender. https://www.amazon.com/Quantum-Physics-Minutes-Gemma-Lavender-ebook/dp/B01MFBP1V6


Thanks, I am not really sure how im going to fill out the form as I don't want to sound too accomplished yet (as I'm not) and since the question says how you plan on achieving this knowledge by the end of your degree, I think I will sign work through some quantum mechanics and python work and look at their applications to cyber security (although im unsure I will know enough about python/quantum computing/mechanics to be able to apply it to cyber security at interview I will say I plan on learning it).

And thanks also for the question, thats actually something I've been looking into and hopefully something I can build up to understanding fully
Original post by isiaiah d
Thanks, I am not really sure how im going to fill out the form as I don't want to sound too accomplished yet (as I'm not) and since the question says how you plan on achieving this knowledge by the end of your degree, I think I will sign work through some quantum mechanics and python work and look at their applications to cyber security (although im unsure I will know enough about python/quantum computing/mechanics to be able to apply it to cyber security at interview I will say I plan on learning it).

And thanks also for the question, thats actually something I've been looking into and hopefully something I can build up to understanding fully


If you can get a copy of the following book (given the draft below and any standard quantum mechanics text, it would make your route toward learning quantum mechanics may "easier".
https://emichels.physics.ucsd.edu/QuirkyQuantumConcepts.pdf
The first 2 chapters of the Quirky Quantum Concept is about the formalism of Quantum mechanics which you need for Quantum computing. You would also need chapter 4 of Quirky Quantum Concept especially density matrix to do quantum computing.

A standard introduction quantum mechanics text (free) would look as follow:
http://farside.ph.utexas.edu/teaching/qm/qm.html

All the best for your learning journey, application, and interview.
Reply 10
Original post by Eimmanuel
If you can get a copy of the following book (given the draft below and any standard quantum mechanics text, it would make your route toward learning quantum mechanics may "easier".
https://emichels.physics.ucsd.edu/QuirkyQuantumConcepts.pdf
The first 2 chapters of the Quirky Quantum Concept is about the formalism of Quantum mechanics which you need for Quantum computing. You would also need chapter 4 of Quirky Quantum Concept especially density matrix to do quantum computing.

A standard introduction quantum mechanics text (free) would look as follow:
http://farside.ph.utexas.edu/teaching/qm/qm.html

All the best for your learning journey, application, and interview.


Thanks alot! I am actually getting more and more interested in this as I go along so pretty sure it's something I'll want to work in in the future even if I don't get on the scheme. Will I likely learn about this stuff at all in a chemical engineering degree or will I mostly be working outside of the degree?
Original post by isiaiah d
Thanks alot! I am actually getting more and more interested in this as I go along so pretty sure it's something I'll want to work in in the future even if I don't get on the scheme. Will I likely learn about this stuff at all in a chemical engineering degree or will I mostly be working outside of the degree?


I doubt that you will learn quantum mechanics (QM) or quantum physics in doing a chemical engineering degree. You may have the option to do modules outside your major and you can select to do QM module in the physics department or faculty in your university.

I think you would do engineering mathematics that covers linear algebra, calculus, ordinary differential equations, partial differential equations and special functions in physics, etc. These are essential for you to learn QM. IMO, you should try to learn the detail of linear algebra and calculus if you want to perform the calculations for the problems in QM and Quantum computing. They are the essential skills for you to learn Quantum Mechanics. You would need to know a bit on probability - A level statistics is good enough.
Reply 12
Original post by Eimmanuel
I doubt that you will learn quantum mechanics (QM) or quantum physics in doing a chemical engineering degree. You may have the option to do modules outside your major and you can select to do QM module in the physics department or faculty in your university.

I think you would do engineering mathematics that covers linear algebra, calculus, ordinary differential equations, partial differential equations and special functions in physics, etc. These are essential for you to learn QM. IMO, you should try to learn the detail of linear algebra and calculus if you want to perform the calculations for the problems in QM and Quantum computing. They are the essential skills for you to learn Quantum Mechanics. You would need to know a bit on probability - A level statistics is good enough.


ok, I've done extra reading on year 1 calculus but stopped around the chain rule for partial derivatives but I'll carry that on now and pick up linear algebra too. I hate probability but I just remembered I think I have a book somewhere that explains the quantum mechanics probability pretty nicely and was basically all of the book I understood so ill try and find that too.

Thanks again for all the help, its much appreciated.
Reply 13
Original post by isiaiah d
From what I understand atoms can be excited(1) or de-excited(0) but why then can qubits take values from 0 to 1. Or am I completely misunderstanding this?

(1) or (0) or (both 1 and 0 at the same time)
Reply 14
Original post by yt7777
(1) or (0) or (both 1 and 0 at the same time)


what is that in terms of excited or not excited though? how can it be both as in it's moving up energy levels?

so, 1 qubit can be any number of states from 0 to 1?
Original post by isiaiah d
what is that in terms of excited or not excited though? how can it be both as in it's moving up energy levels?

so, 1 qubit can be any number of states from 0 to 1?


One thing in QM is that don’t try to be smart to think that you can imagine what is going on in the nano-scale. What you can imagine in classical mechanics is NOT what you can imagine in QM.
https://www.youtube.com/watch?v=sL5ZV3_sY_E

Original post by isiaiah d
what is that in terms of excited or not excited though?


Take hydrogen atom for example. If the electron is promoted to n=2 electron energy level, the hydrogen atom is said to be excited. Not excited means that the electron is in the ground state or stays at n =1 energy level.

Original post by isiaiah d
….so, 1 qubit can be any number of states from 0 to 1?


I would recommend that you take a look at the following description:
https://en.wikipedia.org/wiki/Qubit#Qubit_states

This article explains the difference between a qubit and classical bit
https://www.quora.com/What-exactly-is-a-qubit-and-how-does-it-work

If 1 qubit can be any number range from 0 to 1 basis, then there are an infinite number of basis or state. This means it cannot be a qubit.

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