Teach me about classical mechanics please

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Discussion Overview

The discussion centers around classical mechanics, its foundational concepts, and the transition from basic to more rigorous mathematical understanding. Participants explore related topics such as quantum field theory and its relationship with general relativity, as well as the role of mathematicians in advancing theoretical physics.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant expresses a desire to understand classical mechanics with mathematical rigor, seeking information on key theorems and results.
  • Another participant suggests a Wikipedia article as a comprehensive overview of classical mechanics, highlighting its interconnectedness with other topics.
  • Several posts diverge into discussions about quantum field theory, questioning its role in unifying relativity and quantum mechanics.
  • Participants discuss the challenges of formulating a quantum theory compatible with general relativity, noting that no satisfactory solution currently exists.
  • There is a suggestion that mathematicians could contribute to solving problems in theoretical physics, although the extent and nature of their contributions are debated.
  • One participant emphasizes the complexity of calculations in quantum gravity theories and the need for better mathematical structures and techniques.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the relationship between classical mechanics and quantum field theory, nor on the contributions mathematicians can make to theoretical physics. Multiple competing views and uncertainties remain throughout the discussion.

Contextual Notes

Some discussions touch on the limitations of current theories and the need for further exploration in areas like quantum gravity, but these points remain unresolved and speculative.

Krunchyman
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I have no prior experience in physics, but I am a math undergrad so I know calculus, differential equations, linear algebra and stuff like that. So I'm ready to move from the conceptual "bedtime story physics" to stuff with real mathematical rigor.

So, what is classical mechanics all about? What are the big theorems and results?
 
Physics news on Phys.org
This wikipedia article should give you a good overview of what classical mechanics is all about. Note that this article links to almost everything else about classical mechanics, so you should follow all the links, especially the ones in the expandable/collapsible table in the upper right of the page.
 
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440px-Modernphysicsfields.svg.png


This might not 100% relate to the OP, but it caught my eye...
 

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ISamson said:
View attachment 214443

This might not 100% relate to the OP, but it caught my eye...
Does quantum field theory try to unify relativity and quantum mechanics? If not, what it is supposed to do?
 
Quantum Field Theory is special-relativistic quantum theory. No one has worked out a quantum theory that plays nicely with general relativity, although a lot of effort has gone into looking.
 
Ibix said:
Quantum Field Theory is special-relativistic quantum theory. No one has worked out a quantum theory that plays nicely with general relativity, although a lot of effort has gone into looking.
Can mathematicians contribute to this problem?
 
Krunchyman said:
Can mathematicians contribute to this problem?
Definitely. But ideally they would contribute to the solution.
 
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A.T. said:
Definitely. But ideally they would contribute to the solution.
To what extend can they contribute to the solution? What are the research areas?
 
  • #10
Krunchyman said:
To what extend can they contribute to the solution? What are the research areas?
I'm not qualified to comment directly. My reading of what little I know is that we have no shortage of skilled mathematicians and no shortage of candidates for theories. But none is totally satisfactory, basically because theorists are shooting more or less blind. We haven't yet probed the regime (we may find we need something bigger than CERN) where existing theories differ significantly from experiment.

A.T. is being funny, but I think that's the long form of what he's saying.

You may wish to look at the current (or recently) featured thread on a "krisis" in physics.
 
  • #11
ISamson said:
View attachment 214443

This might not 100% relate to the OP, but it caught my eye...

I prefer the cube:

cube.jpg
 

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  • #12
The Bronstein cube https://en.wikipedia.org/wiki/Matvei_Petrovich_Bronstein
apparently the author of the first dissertation on Quantum Gravity.
http://people.bu.edu/gorelik/cGh_FirstSteps92_MPB_36/MPB-all_94_e_TOC.htm
http://people.bu.edu/gorelik/cGh_Bronstein_UFN-200510_Engl.htm
http://people.bu.edu/gorelik/MPBronstein_100/MPBronstein_100.htm

In my dissertation, I have a hypercube, with an additional "discreteness of spacetime" parameter ranging from discrete to continuous.
 
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  • #13
Yes. One of the issues is that it is difficult to do the calculations on the various quantum gravity theories to determine just what they predict. The math is *hard*. So mathematicians have their work cut out for them -- to find enough structure in the theories so that the calculations become feasible. Just about everything from analysis, Lie group theory, topology, category theory, and the lot seems to get involved. All of which tells me we need more theoretical insights into the theories we already have and better calculating techniques.
 

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