Re: Tipler & Omega in an accelerating cosmos

From: hal@finney.org
Date: Wed Jan 05 2000 - 12:09:18 MST


Damien Broderick, <d.broderick@english.unimelb.edu.au>, writes:
> Just found a response by Tipler to reports of faster cosmic expansion at
>
> http://www.skeptic.com/990107.html

Tipler further explains, in that article:

> But I accept the OPT [Omega Point Theory], since the known physical laws
> leave me no choice. As I pointed out to you in an earlier e-mail, if
> the universe were to expand forever, either because it is open or it is
> accelerated by a postive Lamdba, then Hawking has shown that unitarity
> would be violated. But unitarity is one of the central postulates
> Quantum Mechanics, confirmed again and again by every experiment to
> date.

I am not familiar with the result from Hawking he mentions (and I doubt
that I could understand it anyway). Unitarity is basically a kind of
normalization principle in QM, similar to saying that probabilities
must always add up to 100%. It's not clear why an expanding universe
would violate this, maybe something about the divergence to infinity.
Of course relativity and QM have never been successfully merged, so I
would imagine that any results along these lines have to be considered
somewhat tentative.

It is good to see that Tipler continues to stick to his theory and predict
that the recent observations will ultimately be shown to be in error.
That is what you have to do with a falsifiable theory.

Hal



This archive was generated by hypermail 2b29 : Thu Jul 27 2000 - 14:02:05 MDT