On Fri, Mar 9, 2018 at 11:23 PM, Brent Meeker <meeke...@verizon.net> wrote:
>> Noether's theorem couldn't be invoked and the conservation of momentum >> produced from it unless there was a symmetry, in this case the fact that >> the laws of physics are the same at all points in space. Someone could then >> ask why that is, and at this time the best answer we could give is that’s >> just what we observe. As far as I can see it is not a logical necessity, >> physics could have been different from one place to another but we see that >> is not the case. > > *> If that were the case then we would look for some other variable(s) that > would account for the difference in order to arrive at a more comprehensive > theory* I agree if the laws of physics seemed to change from place to place we’d start looking for hidden variables to explain it, and that is exactly what we should do; but those other variables might not exist and there is no guarantee our hunt will be successful. All we can do is try and do our best. *> The idea of physics as a fundamental theory is that it should be the > same at all times and places. * Yes thats the idea, and you might be able to use the anthropomorphic principle to conclude that fundamental laws of physics must be the same at all times and places, but the anthropomorphic principle itself is just a special sort of observation. It all comes down to observation, you couldn't deduce from pure logic alone that Maxwell's laws of electromagnetism are true in your frame of reference the way Euclid deduced there is no largest prime number, much less deduce that that Maxwell's laws remain true even in a frame of reference moving with respect to you, its just what we observe. That’s why experiment is so important in physics and in all science, that’s why so many beautiful and logically self consistent physical theories have been shot down in flames, they just don’t match what we observe. The universe could have worked some other way but it just doesn’t. *> So if it's not, we either look for a better theory or (temporarily) give > up and call the variations "geography". * You could call it geography but I think a better name would be history, or initial conditions. Even if the universe was as deterministic as Newton thought it was and even if you knew all the laws of physics perfectly you still couldn’t predict exactly what will happen tomorrow if you didn’t know exactly what happened yesterday. John K Clark -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
