[ExI] Public draft of my book 'Tales of the Turing Church

Stuart LaForge avant at sollegro.com
Mon Oct 22 03:08:36 UTC 2018

John Clark wrote:

> It would be difficult to engineer such an observing platform but in
> theory you could observe the heart of the sun, however an observer outside
> of the multiverse looking in at it would not only violate physical law it
> would be a flat out logical contradiction.
> * > If the multiverse contains all possible arrangements of matter and
>> energy in all possible space-times then the multiverse as a whole
>> cannot change.*
> No observer can see the multiverse as a whole, the very idea is self
> contradictory.  The multiverse is at least a 4D object, maybe 5D or even
> more, but however many dimensions it has one thing we know for sure is
> that it's not homogeneous, it does change along all its time dimensions
> and it does change along all its spatial dimensions.

I agree with you that there is no such thing as a vantage point outside
the multiverse. What I still don't understand is how you think that such
fact is related to whether the universe splits in MWI or whether the
Wheeler-DeWitt equation is physically meaningful.

>>> * superluminal inflation would have super-cooled the universe
>>> requiring
>> a "reheating" period which is just kind of glossed over.*
> An expanding gas isn't always cooled, for example if I divide a chamber
> in two and there is a gas at high pressure in half of it and a vacuum in
> the other half and I suddenly remove the barrier between the two the gas
> expands to fill the entire chamber, but the gas isn't cooled because it
> did no work.  Work is force over distance and that didn't happen.  During
> the exponential expansion phase Guth's inflation field did the work not
> the hot gas.

But there was no gas because there were was no matter. You could talk
about a gas of photons but every time the universe doubled in size during
inflation so would have the wavelengths of those photons. Thus inflation
should have cooled the photon gas in accordance with the Planck law for
black body radiation.

So how did it reheat itself afterwards?

Stuart LaForge

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