# Quantum Field Theory



## ehanes7612 (Dec 28, 2017)

I began studying Quantum Field Theory recently ..the math is a lot to rap my head around but I remind myself of the big picture with simple videos like this


enjoy

https://www.youtube.com/watch?v=FBeALt3rxEA


Dr Lincoln has an entire series of videos doing a great job at providing simple explanations to concepts in modern physics


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## abax (Dec 28, 2017)

OMG Hanes, I'm still trying to visualize exactly
how the Big Bang happened according to Tyson!!!
This just confuses me even more on the subatomic level...aaccckkkkk!


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## ehanes7612 (Dec 30, 2017)

abax said:


> OMG Hanes, I'm still trying to visualize exactly
> how the Big Bang happened according to Tyson!!!
> This just confuses me even more on the subatomic level...aaccckkkkk!



it's a terrible name, and what I think leads to a great deal of misconceptions about the theory


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## abax (Dec 30, 2017)

I understand the theory was a whole concept. It's in the
details, in neutrinos, energy released at subatomic levels
that I struggle with. Have you read ASTROPHYSICS FOR
PEOPLE IN A HURRY? It's written for the non-scientist, but it's still somewhat unclear to me. As you delve into
the subject in more detail, I do wish you'd share it with
us...or just me. I like to understand such things.


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## ehanes7612 (Dec 31, 2017)

My study of astrophysics involved a year long intimacy with the mathematical models... if you have a specific question I could try to answer it as best as I can


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## myxodex (Jan 2, 2018)

The maths is always harder to understand if you don't understand the underlying concepts ... and you only get to understand these by studying the maths ... confounding. The BBC has done a series on this that is fairly basic and which I found enjoyable; http://www.bbc.co.uk/programmes/b04v5vjz

As a biologist I found the episode about quantum physics in biology very interesting; especially the bit about photosynthesis.


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## ehanes7612 (Jan 2, 2018)

Photosynthesis is fascinating ( I received my first bachelors in Botany with an emphasis on the cellular level). The first experiments in Quantum Mechanics ( Franck Hertz) is essentially a lesson in photosynthesis as applied to a noble gas ..recognizing the importance of a discrete energy level needed to change the quantum state of an electron .. which is essentially what life is.. the exchange of specific electrons


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## abax (Jan 2, 2018)

O.k., I'm trying to formulate an intelligent question. For
instance, supposedly before the universe existed there was
void or so one assumes. At some point in a timeless void
subatomic particles began to form and interact. Did those particles always exist in that void and chanced to
react? Or is it assumed via mathematics that those particles existed and swirling at random and chance brought them together? That isn't very clear, but I think
you see what I'm getting at.


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## ehanes7612 (Jan 3, 2018)

For a particle to exist there needs to be a certain level of energy that it's associated field reaches so it has the opportunity to 'pop out' , whether it's decreasing or increasing in energy. This is the idea behind devices such as colliders, and is the basic premise behind Quantum Mechanics. So far all evidence is suggesting that there was a time early in the universe when particles didn't exist ..just fields and go back far enough just one field. As the big bang progressed field(s) underwent a process called symmetry breaking, in which the forces of nature (what I am calling fields) separated from each other. One such example was the symmetry breaking that led to the separation of the weak force and the electromagnetic force..conceptually speaking, the universe turned into light at this moment and was no longer opaque, photons came into existence..this is most often referred to as the cosmic microwave background radiation. There are theories that go back further, but these are just theoretical models that have no evidence..it was hoped that string theory would answer these questions but it's not looking like we can test for the validity of string theory with current technology. The most challenging aspect to earliest seconds of the big bang is how gravity played a part and of course developing a working model that included gravity as part of a grand unified field...and does it have a particle associated with it (graviton)..some cosmologists think that we may undergo another symmetry break in the universe..if this happened ..we would all pop out of existence, instantly. Fields don't require depth or the need to occupy a 3-D space, in the same way a particle does..so in essence, you can have an infinite bulk of fields that never take up any space (as we know it in 3-D)


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## abax (Jan 3, 2018)

Thank you. I'll try to get my head around this concept
now one step at a time. Are scientist "assuming" that the
initial energy existed or is it a mathematical certainty?


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## ehanes7612 (Jan 3, 2018)

abax said:


> Thank you. I'll try to get my head around this concept
> now one step at a time. Are scientist "assuming" that the
> initial energy existed or is it a mathematical certainty?



good question...what did all that look like before there was nothing (in this case a singularity?...no one knows and I don't believe there is any mathematical model that has been figured out to explain it


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## Hien (Jan 4, 2018)

another video for someone like you who loves to think and to find out about subjects beyond what average peoples are thinking about. [minute 31.20] but I would recommend watching the whole video anyway

https://www.youtube.com/watch?v=R8VyUsVOic0

I think a lot of times, discoveries will be killed by the establishment corporations and their allies because these discoveries will undermine their profit making machines, even these discoveries will make treatment more affordable and accessible to the rest of humankind




ehanes7612 said:


> I began studying Quantum Field Theory recently ..the math is a lot to rap my head around but I remind myself of the big picture with simple videos like this
> 
> 
> enjoy
> ...


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## ehanes7612 (Jan 4, 2018)

Hien said:


> another video for someone like you who loves to think and to find out about subjects beyond what average peoples are thinking about. [minute 31.20] but I would recommend watching the whole video anyway
> 
> https://www.youtube.com/watch?v=R8VyUsVOic0
> 
> I think a lot of times, discoveries will be killed by the establishment corporations and their allies because these discoveries will undermine their profit making machines, even these discoveries will make treatment more affordable and accessible to the rest of humankind



yeah


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## abax (Jan 4, 2018)

Very interesting research Hien and with practical applications if the funds for sufficient examination were
available. Even the Nobel money won't go very far without
additional funds.

Hanes: thinking about singularities for a bit. Doing some
reading.


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## h_mossy (Jan 6, 2018)

If I was studying quantum entanglement, here are some questions I would have at the outset:

Does the degree of quantum entanglement vary over distance? 

Also, is it affected by the medium through the entanglement occurs? 

Can it be affected by external forces? 

Does entanglement present any sort of particle or wave like attributes. 

Does entanglement occur with all particles, or just specific ones? 

Do the methods by which we observe the entanglement cause any sort of disruption, so that if we were not to observe it would the outcome be the same or different?

Is the entanglement effect useful in some manner to transmit information from point to point almost immediately?

Can the effect be used to transfer more than mere information over distance?

Do we know why entanglement occurs?

Does the quantum entanglement effect hint at any other phenomena which we may one day observe?

Are these questions answered already? Just curious.


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## ehanes7612 (Jan 6, 2018)

Wikipedia has a good synopsis of entanglement .. I haven’t studied it much. The EPR paradox is a good place to start as well as a theoretical understanding of quantum computers


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## ehanes7612 (Jan 6, 2018)

I also believe Leonard Susskind (Stanford and one of the parents of String Theory) has a video on entanglement. A while back he made a series of physics videos for the general community..does require some calculus though..but even without the math you can understand his main points


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## ehanes7612 (Jan 6, 2018)

https://www.youtube.com/playlist?list=PLQrxduI9Pds1fm91Dmn8x1lo-O_kpZGk8

He does give simple math primers ..actually his lectures are more on the algebra level with some calc


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## h_mossy (Jan 6, 2018)

Mahalo for the info. The math will not be a problem as long as he doesn't go into diffy-q's (differential equations).


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## ehanes7612 (Jan 7, 2018)

He gives the solutions for diffeq’s , which is essentially most physics problems. I love differential
Equations, my favorite math... but to study physics on a formal level you have to be comfortable with differential equations


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