Skydive Phil has a new Before the Big Bang episode out, “Can the Universe Create Itself?” In The Boundary Proposal and i-Time, before
having seen the video, I suggested that the answer would be no. Now, after having seen it, my answer remains a
steadfast no. Note that I have changed
the tense in the title of this article, effectively making it a different
question, but the answer to both questions is no.
I think that the star of the video, Gott (amusingly the German word for “god”,
noting that all nouns in German are capitalised), was addressing a different
question: could the universe have emerged from a closed timelike curve? or, could a universe which is temporally
unbounded have a beginning in the finite past?
The answer to both of these, according to Gott, is yes.
My issue, however, is that all the clever folding of space (and balancing
of different types of vacuums to result in zero energy and zero pressure) doesn’t
provide you with an escape from the problem of (infinite) regress in which you
keep going back to an initial state and ask how that “initial” state got there –
at which point you admit to a new “initial” state. Even if there was a primordial closed timelike
loop out which our universe sprung (somehow resulting in the hot dense, pre-Big
Bang state), you can ask how that closed timelike loop got there. And was (is?) the medium in which that closed
timelike loop existed (exists?)? Clearly
it’s not “in space”, but it would be a loop of something, presumably, “in”
something.
I agree that, given the assumption of an initial closed timelike loop, we
could have a universe that just happens due to a quantum fluctuation but I don’t
think we really have an argument here against a theist (the believer in a
different kind of Gott) who might argue for a quantum engineering version of
the Creator, one that carefully sculpts a very specific closed timelike loop –
from nothing and in nothing – out of which the pre-determined universe springs entirely
in accordance with some divinely inscrutable plan.
---
I have a somewhat different view on cosmogony, the origins of the
universe. As I described in The Boundary Proposal and i-Time, I
see this universe as being inside a black hole.
I also see the universe that is “outside” (and in a sense “outwhen”) our
black hole as also being inside a black hole, although I don’t have the same
level of evidence to support that notion – I am just assuming the consistency
of relativity (some of the initial conditions would be not need to be
consistent across universes). And so on,
each universe is encapsulated in a black hole nestled in the next universe up. (I say “up” because a black hole is a gravity
well and you go down into wells.)
Although this universe (and all universes in this chain) may be future
eternal, we can nevertheless consider them as being a sequence of expansion-contraction
phases (ECPs) – because the part that matters, the mass-energy will inevitably contract
even if the empty space around it expands forever.
My concept is that it is possible, if unlikely, under quantum physics for
things to wobble into existence. Not
things like Boltzmann brains, which are far too complex to actually eventuate,
but tiny amounts of mass-energy. Even if
only miniscule amounts of mass-energy eventuate in each link of the universal
chain, the chain is not limited as far as the number of links (the ECPs) so
eventually, you will end up with a universe as large as ours.
I have no idea how much mass-energy could come into existence via quantum
mechanical processes in each universe, but if we limit it to, for example, one joule
per ECP, then to arrive at a universe our size would take 1070 ECPs. This is a lot of iterations and it becomes
less surprising that, eventually, a species such as ours should eventuate. It could be that less mass-energy is added
each time, perhaps the least amount of energy possible at the time it comes into
existence - which today would be c.h/(width of the universe) and that is a
pretty small amount of energy.
Now this idea can be applied to another problem – if only very small
amounts of energy are added each time, how could it be that the first black
hole formed? If there was only a tiny
bit of energy at first it would not be enough to form a black hole, because you
need at least a Planck mass in a Planck volume (which is notionally the
smallest volume). However, if the lowest
amount of mass-energy that can be added by quantum mechanics to a universe is
defined by c.h/(width of the universe) then, when the universe is as small as
it can be, at Planck volume, the width is one unit of Planck length and in that
case the lowest possible amount of energy is precisely one unit of Planck energy,
precisely what you need for your first black hole. This first black hole would commence the ECP
process, which is initially instantaneous (actually one unit of Planck time),
until there is another quantum mechanical event that adds another minimum
amount of energy. So the number of ECPs
between us and that first quantum mechanical event could be, well … astronomical. Beyond astronomical.
In my model, the universe does not create itself, but its beginnings are
extremely humble, it is equivalent to a multiverse – but at least partially sequential
(I have no issue with each individual black hole spawning their own chain of future
eternal universes, prior to be being subsumed in the final universal black
hole) – and it gives support to the idea that a universe as suitable for life
as ours could indeed arise merely by chance, even if “fine tuning” for it were
necessary.
---
I did mention above that the universe, or at least the part of it that
matters, will inevitably contract. This
sounds like it might be a big claim, so I will try to address that another day.
No comments:
Post a Comment
Feel free to comment, but play nicely!
Sadly, the unremitting attention of a spambot means you may have to verify your humanity.