At the end of The Eternally Inflated (Multiverse and WLC),
I mentioned reliance "on argumentation from (false) ignorance". It's a fair question if you were to ask: what
the hell is false ignorance. Let me to
clarify.
An appeal to
ignorance is a fallacy in which, for example, an apologist might say something
like "There is no other known reason why X would happen, therefore god did
it" or "You can't prove that god doesn't exist, therefore it
does".
What I mean by
false ignorance is the sort of move performed by an apologist, where he or she
claims ignorance regarding evidence against his or her case, despite that
evidence being readily available. In some
cases, the feigned ignorance is all the more egregious because not only is the
evidence readily available, but it is a matter of public record (in video and
transcript) that the evidence has been presented.
Here are some
pertinent examples - all centred on arguments raised by WLC - that are raised
by people interviewed by Skydive Phil and co in recent films (look for the tag
"Before the Big Bang"):
Misrepresenting The
BGV theorem
WLC constantly informs us that the BGV theorem means that the universe
had a beginning: (debate with Sean Carroll, March 2014)
"In 2003 Arvind Borde, Alan Guth, and Alexander
Vilenkin were able to show that any universe which is, on average, in a state
of cosmic expansion throughout its history cannot be infinite in the past but
must have a beginning."
One of the authors, Alan Guth says that's not correct, the theorem only
implies that inflation had a beginning. While, it is true that Vilenkin has
subsequently written an article which concludes that the
universe "probably" did have a "beginning", he caveats the
term "beginning" so as to be "synonymous to past
incompleteness" - so this does not necessarily mean an ex nihilo creation
event.
The conclusion to the actual BGV paper is revealing: "Our argument
shows that null and time-like geodesics are, in general, past-incomplete in
inflationary models, whether or not energy conditions hold, provided only that
the averaged expansion condition Hav > 0 holds along these
past-directed geodesics. This is a stronger conclusion than the one arrived at
in previous work in that we have shown under reasonable assumptions that almost
all causal geodesics, when extended to the past of an arbitrary point, reach
the boundary of the inflating region of space-time in a finite proper time (finite
affine length, in the null case)."
Note the caveats: "in general", "provided that", "under
reasonable assumptions", "almost all", "in the null
case". Even if we look past those
caveats, we see that the authors are making a claim about a "boundary of
the inflating region of space-time".
This says nothing about what did or did not exist prior to
that inflation.
Finally, Sean Carroll told WLC this in his rebuttal speech during their
debate: "Now there’s a theorem by Alan Guth, Arvind
Borde, and Alex Vilenkin that says the universe had a beginning. I’ve explained
to you why that’s not true but in case you do not trust me I happen to have
Alan Guth right here. One of the authors of the Borde-Guth-Vilenkin Theorem,
Alan what do you say? He says, “I don’t know whether the universe had a
beginning. I suspect the universe didn’t have a beginning. It’s very likely
eternal but nobody knows.” Now how in the world can the author of the
Borde-Guth-Vilenkin theorem say the universe is probably eternal? For the reasons
I’ve already told you. The theorem is only about classical descriptions of the
universe not about the universe itself."
In his February 2016 debate with Kevin Scharp, WLC trotted out his
version of the BGV again, claiming it as evidence that universe (or multiverse
has an absolute beginning).
Pushing the Past
Eternal
WLC claims, for a number of reasons, that the universe cannot be eternal
in the past. One of the authorities that
he calls on in support of this claim is Alan Guth. Guth explains in Before the Big Bang 4 : Eternal Inflation & The Multiverse why
he favours models that are past eternal.
Despite WLC's protestations, there are a number of models which are consistent
with past eternality: the cyclic model (possibly with one bounce only), conformal
cyclic cosmology, loop quantum gravity and dual arrow of time models such as that
being worked on by Alan Guth and Sean Carroll.
Therefore, WLC's claims are based on false ignorance. He has no justification for believing that
there are no workable cosmologies that are past eternal.
Boltzmann Brains
I'm not big into Boltzmann brains, for reasons that I plan to write
about in the near future. WLC loves them. The reason why he loves them, as best as I
can see, is that it makes physicists look silly when they take the idea
seriously.
However, when WLC raises Boltzmann brains, he does so to discredit the
idea of a multiverse (which he sometimes refers to as a "World Ensemble"). The problem that WLC has when does this, as
Alan Guth points out, is that Boltzmann brains are a problem even for single
universes and the multiverse (particularly the pocket universe solution that creates
new pockets of low entropy space-time in which low entropy observers like
ourselves could develop) is the solution to that problem.
But even if that weren't the case, the argument as presented by WLC
himself is only that high entropy, short-lived Boltzmann brains are more
likely than low entropy, slowly developed observers. There is no claim that we are impossible under
the assumptions being presented. So with
a "World Ensemble" theory, it is possible for intelligent life like
ours to develop and, therefore, given enough "worlds" in that "ensemble"
(as N approaches infinity), the existence of our type of intelligent life within
the ensemble becomes a virtual certainty - no matter how unlikely it might be.
Going Low with Entropy
This is in a similar vein to the Boltzmann brain argument, although a
whole lot less silly. WLC claims that the
second law of thermodynamics, that entropy tends to increase, implies the universe
cannot be past eternal. Again, this is
put to bed by the multiverse, particularly of the sort suggested by Alan Guth and
also the Conformal Cyclic Cosmology championed by Penrose, another physicist who has been widely misrepresented
on this subject by apologists, including WLC.
Both Guth and Penrose suggest that the solution to the mystery of why
the entropy state of the universe was so low prior to the big bang was that
there was a "before" the big bang that put the entropy into a relatively
low state.
Note that I use the term "relatively", by this I mean to
highlight that there is no upper limit to entropy.
Misrepresenting
Anthony Aguirre
In his debate with Sean Carroll, WLC selectively used words from Anthony
Aguirre and John Kehayias to claim that the universe must have had a
beginning:
It is very difficult to devise a system – especially a quantum one –
that does nothing ‘forever,’ then evolves. A truly stationary or periodic
quantum state, which would last forever, would never evolve, whereas one with
any instability will not endure for an indefinite time.
These are taken from the paper "Quantum Instability of the Emergent
Universe". The footnote, provided
to the transcript but not presented at the actually debate, clarifies that
Aguirre's argument is specific to the Ellis-Maarten model but then claims that "their
point is generalizable".
Aguirre himself (in the film) confirms he only claimed
that a particular model (the "Emergent Universe” of the paper's title)
doesn’t work in creating an eternal past, and he goes on to clarify that other
models do work with an eternal past, thus putting a lie to WLC's claim that the
point was "generalizable".
Conformal Cyclic
Cosmology
In one of his podcasts and in a Q&A response, WLC claims that
Penrose's conformal cyclic cosmology (CCC) is not a cyclic model (noting that
he shares credit for this argument with James Sinclair and makes a philosophical
appeal to Yujin Nagasawa's authority).
The general thrust of the argument centres on the claim that Penrose's
model does not describe consecutive cycles of the universe, but rather that the
cycles are concurrent, sharing a common beginning. In Skydive Phil's film of an interview with Roger Penrose, Penrose
directly refutes this notion stressing that the conformal cycles of his cosmology
do not originate in a common beginning and instead are sequential.
This film was released after WLC made his comments about the CCC model,
but it is interesting that Craig has made no effort to modify his position (and
this is despite the fact that one of WLC's own domains, the Reasonable Faith
Forums, contains links to the film).
Ignoring the
Evidence (for Multiverses)
WLC has claimed that there is no
evidence for a multiverse, although does temper this appeal to ignorance with claims
that if we were living in a multiverse, then we should be swamped by Boltzmann
brains (see above). This approach really
needs to be modified now, either by relying more strongly on the rather silly
Boltzmann brain argument, or by moving to a position similar to Jeff Zweerink's
(fundamentally, he claimed - at least in the linked clip - that no matter
whether a multiverse exists or not, the case for christianity will be made
stronger). To be able to make this
latter claim, however, will demand a new stratum of false ignorance as WLC and
his fellow apologists wilfully ignore the consequences of multiversality.
If WLC were instead to continue to claim that there is no evidence for a
multiverse, he would be wilfully ignoring the words of George Efstathiou, one
of the world's top observational cosmologists, who gave a press conference for
ESA's Planck satellite (and spoke during the film) saying that there is
evidence for a multiverse. Very
specifically, there is evidence of inflation and inflation of the sort that
very strongly favours a multiverse.
So, in conclusion,
what I mean by an appeal to (false) ignorance is the sort of ploy in which an apologist
either pretends to not know about inconvenient facts, or protects his argument
against contamination by inconvenient facts, and effectively makes a doubly
fallacious appeal to ignorance. WLC
seems to have been guilty of this in at least seven cases.
I say "seems"
because it's possible that I have been overly harsh and WLC is in the process
of fixing his errors. We will know that
to be the case if, in the future, his debates no longer make these appeals to
false ignorance.
Either way, a couple
of his key arguments are in tatters.
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.