# Tag Info

0

Formulating dynamics in terms of least action is well known. See, e.g., wikipedia: http://en.wikipedia.org/wiki/Principle_of_least_action For a nice quantum mechanical treatment see: Feynman and Hibbs (http://www.amazon.com/Quantum-Mechanics-Path-Integrals-Emended/dp/0486477223) For a standard application in QFT see Peskin and Schroder ...

2

I just want to point out that the dimensionality of spacetime is a bit of a fluid concept in string theory. Superstring theory can only be formulated in 10 dimensions, but it can be shown to be dual to an 11-dimensional theory called M-theory. It has also been conjectured to be dual to a 12-dimensional theory known as F-theory, although whether or not this ...

0

I think it is interesting to pose this question in the setting of a very simple hypothetical universe. Suppose that the universe consisted, for example, exclusively of perfectly hard spheres that move according to classical physics and collide with each other elastically. (Really, the specific rules of our toy universe don't matter for what I will say, as ...

3

The existence of undecidable statements does not mean that we cannot hypothetically manage, adding suitable consistent axioms, to determine the truth of all physically relevant statements. Suppose you have a theory $L$ with a meaningful undecidable statement $A$, such that both $L+A$ and $L+\bar{A}$ (I use bar for negation) are consistent. Then you can ...

Top 50 recent answers are included