Sure is quiet around here. I can’t blog much, as I’m in the final throes of book-writing. So instead, let’s have some user-generated content!
Here is a figure that I’ve drawn for use in my book.
Your mission, should you choose to accept it, is to figure out what the figure is supposed to be illustrating, and what lesson is purportedly conveyed. (Hint: that’s supposed to be an egg.) How hard can it be?
If it’s a fruitful exercise, we can repeat for other figures, similarly inscrutable.
something about entropy ?
Hmmm… That entropy just happen to be very low at the big-bang event as a result of a statistical fluctuation, and that the thermodynamic arrow of time is only locally relevant?
Hi Sean,
Thanks for the Boltzmann Egg. I think it might have been more fun to let it go through the chicken phase first (and after), which would be a new twist on an old problem.
It’s kind of remarkable that I managed to avoid “Which came first?” jokes entirely. So far, anyway.
Sorry to spoil your run.
This is your Boltzmann brain on drugs… 😉
Which came first?
The intact egg ALWAYS comes before the broken egg… right?
First one is a Boltzman brain illustration, second is an illustration to your silly idea of different time arrows in same universe, separated by vast time periods – same stuff as in SciAm, methinks.
From what I can tell, you’re trying to collapse the wave function of Schrodinger’s breakfast.
Actually, scratch that. The bottom sequence is an illustration to cyclic universe. The lesson seems to be that a cyclic universe is more likely than Boltzmann brain. Then you probably go on about how the idea you preach is even more likely.
It’s an illustration of the fact that a somewhat low entropy fluctuation (a broken egg) is much more likely than a very low entropy fluctuation (all the way to a whole egg that then breaks).
It’s an illustration of what happens when physicists take their theories way too seriously.
The second row could be our universe, assuming the arrows are not actually the perceived arrows of time (in which case they would go point from the central low-entropy condition).
The first row is clearly a Boltzmann Omelet.
Both are hypothetical fluctuations in a classical phase space, the lower one follows a symmetric evolution in the slices. Both are wrong since classical phase space is only an approximation applicable to macroscopic, large N observations. The above are not possible in the full quantum description relying on einselection.
The first thing I thought of when I saw these is “looks like something religious fundamentalists would use to mock the big bang or evolution”.
“Clearly, these pictures demonstrate the impossibility of particles spontaneously forming a complete egg, much like throwing a bunch of 747 parts into a pile will never form a 747. Therefore, there must be a creator.”
Then the remainder of my brain kicked in and said, ‘entropy discussions and statistical fluctuation’.
I reckon Jason Dick is right, as far as the book goes.
As far as the physics goes, way above my pay grade. I do wonder, tho, what is the logical nature of Sean’s objection to the “naive” view that it is simply a fact about the physical world that the universe began in a state of minimum entropy. Is that an empirical issue that could in principle be settled observationally? Is the objection aesthetic? Or is there some fundamental reason why that *could not* be the case?
I’m sorry, It’s not a fruitful exercise.
It’s an egg.
Others have already said it briefly, so I’ll say it verbosely, because that’s what I do.
Imagine that our relatively low-entropy universe formed as a chance fluctuation out of a high-entropy background. That’s very unlikely, of course, but given a sufficiently long time it could happen. But that wouldn’t be an acceptable explanation of where our universe came from, for the following reason: our universe is pretty low-entropy today, but we know that it was even lower in entropy in the past. So if it formed via a chance fluctuation, it’d be like the bottom picture: the fluctuation would form first the broken egg (like us today) then keep fluctuating down in entropy to form the whole egg (like us in the distant past) then back. That’s exponentially more unlikely than the top panel, where you fluctuate straight to us today, without producing our past first.
So the formation-by-chance-fluctuation hypothesis can’t do the trick, because it still leaves what we see as incredibly unlikely.
If the roughly isotropic frames are a Boltzmann Omelet, and not just Boltzmann scrambled eggs, there’s the matter of the cheese. And the bacon. I doubt Boltzmann bacon will be a pretty thing to illustrate (I don’t even want to think about Boltzmann cheese), so I’d say stick with scrambled.
Illustration that there more ways, or states, for an egg to be in brokenness than there are for an egg to be whole. And somehow that’s an explanation for the arrow of time.
Jason and Ted are right, of course. But we’re always happy to provide others with an opportunity to get their grumpy on.
lemuel, it’s certainly possible that the universe simply began in a very unlikely state, without any deeper explanation being attached to it. It just seems more fruitful to wonder whether that unlikely state is a clue to the operation of some dynamical process, and try to work out what that might be. At this point we have no way of distinguishing, but we hope to someday do better.
Sean,
Sorry about posting a not-so-related-to-the-post question here. Maybe I could have just sent you a private email, but I think your readers are also very informed in this so I will post it here. I am going to teach a class called “Origin” next fall. A part of class is about how the universe began. The class is for general audience and now I have to choose a textbook for it. I will cover standard BB and inflation, but also want to talk about more recent stuffs like string inspired etc. Do you know of any good popularized book for this? I only know of Brian Greene’s “the elegant universe”. If anyone has any suggestion with a bit detail description I would be really appreciate it.
P.S. For the beginning of the life part, I will probably use Paul Davies “the Fifth miracle.” But, if you have other suggestion, that will be welcomed, too.
Demian Cho
Isn’t it a bit misleading to show the early universe as being as disorder?
Could it be better depicted as a transition from a highly order crystal with global symmetries to a less order crystal that has only local symmetries? With the egg occuring at a scale somewhere around ten orders of magnitude larger then the scale of the existing local symmetries.
What a Goldilocks coincidence that we occur exactly at the scale where anything bigger is statistical isotropic and anything smaller is symmetrically isotropic, and that this is precisely the same scale that is dominated by electrodynamic interactions. Not too hot, not too cold, not too messy, not too organized.
Are they screen captures from a cookery programme as seen on a TV with very poor reception?
Having read your blog (in particular your many posts on Boltzmann’s brain, the arrow of time, the low-entropy conditions of the early universe, etc.) definitely makes this challenge easier. Got any inscrutable pictures you haven’t already blogged about?
Personally, I like Aaron F.’s answer the best.