# Tag Info

1

There is no particular reason for integrating from a to b, or b to a. The important thing is the difference in potential between two points. However when integrating be careful with changing the signs (add a negative sign for the integral of b to a). So $V_{a} - V_{b} = V_{b} - V_{a} = \Delta V$

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He is taking the log of the quotient of two radii. Since radii are always non-negative, the quotient is non-negative, so the absolute value can be omitted.

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Wolfram claims that the universe at its core is described by some Turing universal computations (it doesn't matter what specific form it takes, such as cellular automata, tag systems, Peano arithmetic etc)as all Turing universal computations are equivalent). He also claims that mathematical descriptions are a special case of general computations where you ...

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I'll add a small disclaimer as well, I am a mathy with little to no physics background, so if any of the below needs expanding, feel free to ask! (Though I'll mention that I felt a lot more comfortable with this stuff when I first computed the induced actions I'll mention below and really got my hands dirty verifying everything.) To see that there is only ...

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