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Given well-behaved (ie relatively flat-ish) spacetime, there's a distinction between light cones going this way, and light cones going that way (a particle is a

by a1369209993 5y ago

Given well-behaved (ie relatively flat-ish) spacetime, there's a distinction between light cones going this way, and light cones going that way (a particle is a graph[0] edge that is attached to this-ward side of one event and the that-ward side of another), but general relativity, quantum mechanics, and particle physics - assuming you also handle the charge and parity from CPT symmetry - don't distinguish which of 'this' versus 'that' is past or future. 0: Quantum field theory makes this more complicated, since particles are more like amplitude distributions over possible graph edges, except events also aren't vertices but distributions over vertices, and if you can figure out a way to explain this that actually makes sense you might win a nobel prize, but it empirically is well aproximated by a graph at macro scales.

prof-dr-ir 5y ago
I would imagine that a theoretical physicist on LSD would sound like these comments. I love it. But more seriously (and with tons of respect, because these topics are difficult) - why invoke all these complicated concepts? When we discuss statistical mechanics it is kind of understood that the ferromagnet we try to describe is not placed on the innermost stable orbit around a black hole, and similarly when I look in a mirror there is little need to worry about the difference between P and CPT. I guess one can say that the essence of a physical system is not always in the fundamentals of physics? Having said that, I do not know what "intelligence" is, so I do not know how to relate it to entropy.
- a1369209993 5y ago
  > I would imagine that a theoretical physicist on LSD would sound like these comments. I love it. I don't need LSD! > When we discuss statistical mechanics it is kind of understood that the ferromagnet we try to describe is not placed on the innermost stable orbit around a black hole If your theory of statistical mechanics requires that, then your theory is wrong, or at least badly incomplete. That might not be a problem you need to care about for practical reasons, but it is a problem. > I guess one can say that the essence of a physical system is not always in the fundamentals of physics? Depends on what you mean by "essence" and "fundamentals" - you're not going to have good time trying to analyze a computer [0] running a game-of-life sim in terms of it's constituent quarks, obviously - but there's usually something useful to be learned from the underlying physical laws. 0: (whose primary descriptive quality is that it's)

prof-dr-ir 5y ago

I would imagine that a theoretical physicist on LSD would sound like these comments. I love it. But more seriously (and with tons of respect, because these topics are difficult) - why invoke all these complicated concepts? When we discuss statistical mechanics it is kind of understood that the ferromagnet we try to describe is not placed on the innermost stable orbit around a black hole, and similarly when I look in a mirror there is little need to worry about the difference between P and CPT. I guess one can say that the essence of a physical system is not always in the fundamentals of physics? Having said that, I do not know what "intelligence" is, so I do not know how to relate it to entropy.

a1369209993 5y ago
> I would imagine that a theoretical physicist on LSD would sound like these comments. I love it. I don't need LSD! > When we discuss statistical mechanics it is kind of understood that the ferromagnet we try to describe is not placed on the innermost stable orbit around a black hole If your theory of statistical mechanics requires that, then your theory is wrong, or at least badly incomplete. That might not be a problem you need to care about for practical reasons, but it is a problem. > I guess one can say that the essence of a physical system is not always in the fundamentals of physics? Depends on what you mean by "essence" and "fundamentals" - you're not going to have good time trying to analyze a computer [0] running a game-of-life sim in terms of it's constituent quarks, obviously - but there's usually something useful to be learned from the underlying physical laws. 0: (whose primary descriptive quality is that it's)