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Re: QM and GR.

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On 23/07/2016 2:09 AM, Greg Buttler wrote:
> Sylvia Else wrote:
>
>> There cannot be two different correct theories, because if they're
>> different, they'll sometimes give different answers, and at least one
>> would have to be wrong.
>
> I'm not sure it works like that. You may easily have to distinct theories
> predicting same outcome. However, the discussion is not about it, but
> combining all existing theories into a single one. There is no need for
> that.
>

If you have two separate theories that address disjoint aspects of 
physics - that is, there are no areas of physics that both theories 
address - then you can trivially put them together to form a single theory.

Most of the time, though, that's not the situation we have. General 
relativity has little to say about the microscopic world, and quantum 
mechanics has little to say about the macroscopic world. But little is 
not nothing, and one can imagine circumstances in which both these 
theories have something to say, but what they say is different. The 
problem them is to determine what they should say (by experiment), and 
then find a way of modifying one or (more likely) both theories so that 
they say that thing. Once that's done such that both theories always say 
the same thing, there's an expectation that we'll find that they're 
mathematically equivalent - that is, that there's a single theory.

Though it seems inevitable that eventually the required experiments 
cannot be done because the conditions for them are unobtainable. So 
rather than having a single theory of everything, we'll probably end up 
with multiple theories of everything that make different predictions, 
but only for conditions we can neither create, nor find in the 
observable universe. At that point, I suppose science becomes philosophy.

Sylvia.

Sylvia.

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Re: QM and GR. Greg Buttler <grgb@novotnysite.org> - 2016-07-22 16:09 +0000
  Re: QM and GR. edprochak@gmail.com - 2016-07-24 17:19 -0700
  Re: QM and GR. Sylvia Else <sylvia@not.at.this.address> - 2016-07-25 12:21 +1000
    Re: QM and GR. "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-07-25 11:06 -0700
      Re: QM and GR. Sylvia Else <sylvia@not.at.this.address> - 2016-07-26 13:00 +1000
        Re: QM and GR. "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-07-27 09:44 -0700
          Re: QM and GR. "hanson" <hanson@quick.net> - 2016-07-27 12:51 -0700
    Re: QM and GR. Tsvetana Kasatkina <tzve@noemail.info> - 2016-07-29 20:23 +0000
      Re: QM and GR. noTthaTguY <abu.kuanysh05@gmail.com> - 2016-07-31 19:05 -0700
      Re: QM and GR. Sylvia Else <sylvia@not.at.this.address> - 2016-08-19 13:05 +1000

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