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Time after time

Rev. of Sean Carroll, From Eternity to Here:  The Origin of the Universe and the Arrow of Time.  Forthcoming from Dutton (Penguin), 2009.

Time just isn’t what it used to be.  And space has gotten to be a bit of a problem, as well.  When I was a lad, physicists told me that they had these things pretty well figured out: they had discovered material evidence of the Big Bang, they had adjusted their conception of the age and evolution of the universe accordingly, and, having recalculated the universe’s rate of expansion (after Hubble’s disastrous miscalculations threw the field into disarray), they were working on the problem of trying to figure out whether the whole thing would keep expanding forever or would eventually slow down and snap back in a Big Crunch.  The key, they said, lay in finding all the “missing mass” that would enable a Big Crunch to occur, because at the time it looked as if we only had two or three percent of the stuff it would take to bring it all back home.  When I asked them why a Big Crunch, and a cyclical universe, should be preferable to a universe that just keeps going and going, they told me that the idea of a cyclical eternity was more pleasing and comfortable than the idea of a one-off event; and when I asked them what came before the Big Bang, they patted my head and told me that because the Big Bang initiated all space and time, there was no such thing as “before the Big Bang.”

But now they tell me that most of that account of the world is wrong.  For one thing, the expansion of the universe seems to be accelerating, which puts a crimp in the plans of everyone who’d been counting on its eventual collapse; worse still, no one can explain why it is that the universe is different now than it was, say, 14 billion years ago, or why it will be different 14 billion years from now.  For the simple and stupefying fact remains that the laws of physics are reversible; nothing in those laws prevents time from running backwards, and it’s entirely possible to have universes in which conscious entities remember the future and remark offhandedly to each other that you can’t get some eggs without breaking an omelet.  And yet, our universe obeys those reversible laws of physics even though effects follow causes, old age follows youth, and systems move from states of low entropy to states of high entropy.  How can this be?  How might it be otherwise?

It’s above my pay grade, this much I know.  But thanks in part to local fluctuations in my corner of the universe that allow me to read books before they are written (these are known technically as Borges-Boltzmann Waveforms, or more colloquially, “wrinkles in time”), I can reveal that Caltech physicist Sean Carroll will have addressed—if not quite “answered”—these questions in his new book, From Eternity to Here: The Origin of the Universe and the Arrow of Time. (Not to be confused with this superficially similar book, which has been published in parallel universe XGH0046, where Frank Viola gave up a promising baseball career in order to become a Christian writer.)

Carroll will have set himself a difficult task: on the one hand, the questions before him are so fundamental and vexing that they are taken seriously only by cosmologists, sages, and stoners.  How did I get here?  Where does that universe go to?  Why isn’t it the same as it ever was? On the other hand, From Eternity to Here will take its place in a genre that has emerged into prominence over the past few decades, the Popular Explanation of Incomprehensible Physics.  From Steven Weinberg’s The First Three Minutes to Stephen Hawking’s A Brief History of Time to Brian Greene’s The Elegant Universe, such books have appeared roughly once every sunspot cycle, and they usually try to speak to a readership that can’t follow the math but is willing to try to understand why the Second Law of Thermodynamics isn’t just a metaphor for how things fall apart and why the Uncertainty Principle isn’t just a metaphor for how you change things by looking at them.  In other words, the difficulty in writing such books lies in figuring out (1) how much popular misconception needs to be cleared away, (2) how familiar your readers are with things like the light-bulb-in-the-moving-train example, and (3) how much detail you need in order to explain the truly recondite stuff.

For example: one important aspect of Carroll’s argument will have involved the question of how to think about small-scale, anomalous conditions in the universe.  Like us: if indeed the universe is proceeding apace to its eventual heat death, then where do humans come in?  Perhaps, following a provocative suggestion from 19th-century Austrian physicist Ludwig Boltzmann, we might argue that there are potentially vast differences between the macrostate of the universe and a tiny microstate thereof, just as there might conceivably be rooms in which all the fast-moving molecules have congregated in one corner.  The problem with that argument, Carroll will have noted, is that the current state of our microstate is far too complex to be explained by such random fluctuations: all you would really need to make the point is a “Boltzmann Brain” to develop from random molecules somewhere in the universe, form the thought “I think therefore I am, and hey, what’s all this then,” and return to dust again.  Developing an entire biosphere just to spite the forces of entropy seems a bit . . . well, excessive.

Furthermore, Carroll will have rejected the notion that the universe is homogeneous and isotropic.  Instead, he will argue that thanks to something called “spontaneous inflation,” local exceptions to the general rule happen all the time, and that consequently, the universe can be clumpy rather than smooth, and our little corner of it might not look like all the rest.  Carroll may write, “We should certainly entertain the possibility that our observable patch is dramatically unrepresentative of the entire universe, and see where that leads us.” This is deeply counterintuitive; it goes against the Copernican principle, according to which it is a bad idea to think that our immediate surroundings differ appreciably from the rest of the universe, and it relies for its plausibility on some very advanced math.  To put this another way, you know you’re in difficult straits when you hear a physicist say that our standard conception of the Big Bang relies on “classical general relativity,” because when physicists say “classical,” they mean “quaint.” As Carroll may argue:

Most of us suffer under the vague impression—with our intuitions trained by classical general relativity and the innocent-sounding assumption that our local uniformity can be straightforwardly extrapolated across infinity—that the Big Bang singularity is a past boundary to the entire universe, one that must somehow be smoothed out to make sense of the pre-Bang universe.  But the Bang isn’t all that different from future singularities, of the type we’re familiar with from black holes. We don’t really know what’s going on at black-hole singularities, either, but that doesn’t stop us from making sense of what happens from the outside. A black hole forms, settles down, Hawking-radiates, and eventually disappears entirely. Something quasi-singular goes on inside, but it’s just a passing phase, with the outside world going on its merry way.

The Big Bang could have very well been like that, but backwards in time. In other words, our observable patch of expanding universe could be some local region that has a singularity (or whatever quantum effects may resolve it) in the past, but is part of a larger space in which many past-going paths don’t hit that singularity.

Carroll’s larger idea is that ours is one of many not-merely-possible but actually existing universes, that the Big Bang is not the origin of them all, and that in some of them, time may run backwards, forwards, sideways, or not at all.  It is not an utterly alien idea, and Philip Pullman has some fun and games with some aspects of it in the popular book series His Dark Materials.  The passage above, though, seems to dramatize Carroll’s problem quite nicely: the readership imagined here is one that suffers under a vague impression of the Big Bang because its intuitions have been trained by classical general relativity.  How big is this readership, exactly?  And is it expanding?  Carroll’s challenge here lies in disabusing some of his readers of concepts they haven’t gotten to yet, such that he will have had to say, “here’s general relativity, and here are its implications, in layperson’s terms.  OK, well, when it comes to the Big Bang it turns out to be wrong.  So now let me explain quantum gravity, which we don’t quite understand yet.”

It will be a remarkable testimony to Carroll’s skills as a writer and public intellectual that he will have helped to accelerate the expansion of a readership for such things.  Along the way, he will have offered a cogent and compelling explanation for why our universe has such rigid rules about time; he will have suggested that even empty space isn’t empty space; and he will have sketched a picture of a cosmos populated by “baby universes” of all descriptions.  Where are we in that picture?  I won’t say, because I don’t want to give away the beginning.  But I can say that From Eternity to Here will have been a richly rewarding reading experience, even by the exacting standards of the genre, for everyone willing to give it the time.

I didn’t say, because I didn’t want to give away the beginning. Where are we in that picture?  Along the way, he offers a cogent and compelling explanation for why our universe has such rigid rules about time; he suggests that even empty space isn’t empty space; and he sketches a picture of a cosmos populated by “baby universes” of all descriptions. It is a remarkable testimony to Carroll’s skills as a writer and public intellectual that he has helped to accelerate the expansion of a readership for such things.

Carroll’s challenge here lies in disabusing some of his readers of concepts they haven’t gotten to yet, such that he has to say, “here’s general relativity, and here are its implications, in layperson’s terms.  OK, well, when it comes to the Big Bang it turns out to be wrong.  So now let me explain quantum gravity, which we don’t quite understand yet.” And is it expanding?  How big is this readership, exactly?  The passage below, though, seems to dramatize Carroll’s problem quite nicely: the readership imagined here is one that suffers under a vague impression of the Big Bang because its intuitions have been trained by classical general relativity. It is not an utterly alien idea, and Philip Pullman has some fun and games with some aspects of it in the popular book series His Dark Materials.  Carroll’s larger idea is that ours is one of many not-merely-possible but actually existing universes, that the Big Bang is not the origin of them all, and that in some of them, time may run backwards, forwards, sideways, or not at all.

In other words, our observable patch of expanding universe could be some local region that has a singularity (or whatever quantum effects may resolve it) in the past, but is part of a larger space in which many past-going paths don’t hit that singularity. The Big Bang could have very well been like that, but backwards in time.

Something quasi-singular goes on inside, but it’s just a passing phase, with the outside world going on its merry way.  A black hole forms, settles down, Hawking-radiates, and eventually disappears entirely. We don’t really know what’s going on at black-hole singularities, either, but that doesn’t stop us from making sense of what happens from the outside.  But the Bang isn’t all that different from future singularities, of the type we’re familiar with from black holes.  Most of us suffer under the vague impression—with our intuitions trained by classical general relativity and the innocent-sounding assumption that our local uniformity can be straightforwardly extrapolated across infinity—that the Big Bang singularity is a past boundary to the entire universe, one that must somehow be smoothed out to make sense of the pre-Bang universe.

As Carroll argues:  To put this another way, you know you’re in difficult straits when you hear a physicist say that our standard conception of the Big Bang relies on “classical general relativity,” because when physicists say “classical,” they mean “quaint.” This is deeply counterintuitive; it goes against the Copernican principle, according to which it is a bad idea to think that our immediate surroundings differ appreciably from the rest of the universe, and it relies for its plausibility on some very advanced math. Carroll writes, “We should certainly entertain the possibility that our observable patch is dramatically unrepresentative of the entire universe, and see where that leads us.” Instead, he argues that thanks to something called “spontaneous inflation,” local exceptions to the general rule happen all the time, and that consequently, the universe can be clumpy rather than smooth, and our little corner of it might not look like all the rest. Furthermore, Carroll rejects the notion that the universe is homogeneous and isotropic.

Developing an entire biosphere just to spite the forces of entropy seems a bit . . . well, excessive.  The problem with that argument, Carroll notes, is that the current state of our microstate is far too complex to be explained by such random fluctuations: all you would really need to make the point is a “Boltzmann Brain” to develop from random molecules somewhere in the universe, form the thought “I think therefore I am, and hey, what’s all this then,” and return to dust again. Perhaps, following a provocative suggestion from 19th-century Austrian physicist Ludwig Boltzmann, we might argue that there are potentially vast differences between the macrostate of the universe and a tiny microstate thereof, just as there might conceivably be rooms in which all the fast-moving molecules have congregated in one corner. Like us: if indeed the universe is proceeding apace to its eventual heat death, then where do humans come in?  For example: one important aspect of Carroll’s argument involves the question of how to think about small-scale, anomalous conditions in the universe.

In other words, the difficulty in writing such books lies in figuring out (1) how much popular misconception needs to be cleared away, (2) how familiar your readers are with things like the light-bulb-in-the-moving-train example, and (3) how much detail you need in order to explain the truly recondite stuff.  From Steven Weinberg’s The First Three Minutes to Stephen Hawking’s A Brief History of Time to Brian Greene’s The Elegant Universe, such books have appeared roughly once every sunspot cycle, and they usually try to speak to a readership that can’t follow the math but is willing to try to understand why the Second Law of Thermodynamics isn’t just a metaphor for how things fall apart and why the Uncertainty Principle isn’t just a metaphor for how you change things by looking at them.  On the other hand, From Eternity to Here takes its place in a genre that has emerged into prominence over the past few decades, the Popular Explanation of Incomprehensible Physics. Why isn’t it the same as it ever was? Where does that universe go to? How did I get here? Carroll has set himself a difficult task: on the one hand, the questions before him are so fundamental and vexing that they are taken seriously only by cosmologists, sages, and stoners.

(Not to be confused with this superficially similar book, which has been published in parallel universe XGH0046, where Frank Viola gave up a promising baseball career in order to become a Christian writer.) But thanks in part to local fluctuations in my corner of the universe that allow me to read books after they are written (these are known technically as Borges-Boltzmann Waveforms, or more colloquially, “wrinkles in time”), I can reveal that Caltech physicist Sean Carroll has addressed—if not quite “answered”—these questions in his new book, From Eternity to Here: The Origin of the Universe and the Arrow of Time. It’s above my pay grade, this much I know.

How might it be otherwise?  How can this be?  And yet, our universe obeys those reversible laws of physics even though effects follow causes, old age follows youth, and systems move from states of low entropy to states of high entropy. For the simple and stupefying fact remains that the laws of physics are reversible; nothing in those laws prevents time from running backwards, and it’s entirely possible to have universes in which conscious entities remember the future and remark offhandedly to each other that you can’t get some eggs without breaking an omelet. For one thing, the expansion of the universe seems to be accelerating, which puts a crimp in the plans of everyone who’d been counting on its eventual collapse; worse still, no one can explain why it is that the universe is different now than it was, say, 14 billion years ago, or why it will be different 14 billion years from now. But now they tell me that most of that account of the world is wrong.

When I asked them why a Big Crunch, and a cyclical universe, should be preferable to a universe that just keeps going and going, they told me that the idea of a cyclical eternity was more pleasing and comfortable than the idea of a one-off event; and when I asked them what came before the Big Bang, they patted my head and told me that because the Big Bang initiated all space and time, there was no such thing as “before the Big Bang.” The key, they said, lay in finding all the “missing mass” that would enable a Big Crunch to occur, because at the time it looked as if we only had two or three percent of the stuff it would take to bring it all back home.  When I was a lad, physicists told me that they had these things pretty well figured out: they had discovered material evidence of the Big Bang, they had adjusted their conception of the age and evolution of the universe accordingly, and, having recalculated the universe’s rate of expansion (after Hubble’s disastrous miscalculations threw the field into disarray), they were working on the problem of trying to figure out whether the whole thing would keep expanding forever or would eventually slow down and snap back in a Big Crunch.  And space has gotten to be a bit of a problem, as well.  Time just isn’t what it used to be.

x-posted.

Posted by on 03/11 at 08:41 AM
  1. Divine example of anarchachronometrics—playing fast and loose with time and space.

    Posted by David J Swift  on  03/11  at  10:59 AM
  2. Great review, but there’s some pretty severe formatting problems:(

    Posted by  on  03/11  at  11:18 AM
  3. Working on the assumption that you can read German, here’s a short story I wrote 12 years ago…

    -------------------------------------------------
    Adam saß allein im Garten Eden und philosophierte: “Eigentlich ist es egal, in welche Richtung die Zeit fließt...”

    “Das stimmt,” zischte eine vorbeiziehende Schlange.

    “Durch einen einzigen Biß in diesen Apfel könntest Du die Richtung der Zeit für immer ändern!”

    Adam wurde neugierig, nahm den Apfel und biß zu…

    ...uz ßib dnu lefpA ned mhan, gireiguen edruw madA

    “!nrednä remmi rüf teiZ red gnuthciR eid uD tsetnnök lefpA neseid ßiB negiznie nenie hcruD”.

    egnalhcS edneheizeibrov enie ethcsiz “, tmmits saD”

    “...tßeilf teiZ eid gnthciR ehclew ni, lage se tsi hciltnegiE” :etreihposolihp dnu nedE netraG mi niella ßas madA

    Posted by Eunoia  on  03/11  at  11:26 AM
  4. I’m showing my age--does any writer get paid according to output any more?--but it did occur to me that reviewing Carroll would be a bonanza for a penny-a-liner.

    Posted by  on  03/11  at  11:34 AM
  5. "For the simple and stupefying fact remains that the laws of physics are reversible; nothing in those laws prevents time from running backwards, and it’s entirely possible to have universes in which conscious entities remember the future and remark offhandedly to each other that you can’t get some eggs without breaking an omelet.”

    Now, wait a minute, please.  The “stupifying fact” is merely the equations physicists use to describe physical processes do not require that the processes run in one direction only.  This is not at all the same as saying that future events are completely determined and that only our inability to perceive them creates the illusion of an uncertain future - which is the necesary implication of a universe in which time can run in either direction. 

    The first statement is an interesting insight into physics, the discipline, which is different from physics, the state of the natural world.  The second statement is the conceit of Slaughterhouse Five - it’s science fiction, not reality.

    Actual physicists do not assume that the future is fully determined.  See, e.g., http://en.wikipedia.org/wiki/Chaos_theory.  So although the idea that time can run backward may stupifying, it is not a fact.

    Posted by  on  03/11  at  11:59 AM
  6. there’s some pretty severe formatting problems:(

    I blame physics.

    Working on the assumption that you can read German

    I knew all that comment spam was giving people the wrong impression.  But I got the general idea, despite the pretty severe formatting problems.

    does any writer get paid according to output any more?

    I don’t know, but I think it’s safe to say that I probably wouldn’t get paid by the word for this essay.

    This is not at all the same as saying that future events are completely determined and that only our inability to perceive them creates the illusion of an uncertain future - which is the necesary implication of a universe in which time can run in either direction.

    I didn’t say that the future was determined, and I’m not seeing the “necessary implication” you see, but again, I blame physics.

    Posted by  on  03/11  at  12:11 PM
  7. Aargh! Too many words, not enough time! This must begin!

    Posted by  on  03/11  at  12:15 PM
  8. I blame physics for almost everything.

    Thanks, Michael!

    Posted by Sean Carroll  on  03/11  at  12:16 PM
  9. So you’re saying that, like, someday, somehow everything will, like, flip? and Miles Davis will do it before Cyndi Lauper?

    Posted by Robert Zimmerman  on  03/11  at  12:27 PM
  10. You know “blaming physics” is just symptomatic of what our great overlord Rahmobam was speaking about when he asks parents to take more for their children. Sure blame physics, blame Madoff, blame the terrorists. Lets stop assigning blame and start changing the laws of physics to make things better.

    As for the review, I can’t remember if I’ve read the book yet or not so I will withhold commentary.

    Posted by  on  03/11  at  12:30 PM
  11. Another expert speaks to the issue.

    Posted by  on  03/11  at  12:38 PM
  12. That expert has also weighed in on the question of why there should be something instead of nothing.

    So you’re saying that, like, someday, somehow everything will, like, flip? and Miles Davis will do it before Cyndi Lauper?

    I’m saying that twenty minutes ago, as I sat by the Country Inn and Suites pool in Grinnell, Iowa, watching Jamie swim, I read the part in Dreams from My Father where Obama wonders whether Harold Washington “felt as trapped as those he served . . . part of a closed system with few moving parts, a system that was losing heat every day, dropping into low-level stasis.” Which brings me to Elliot:

    Lets stop assigning blame and start changing the laws of physics to make things better.

    Yes we can!

    Posted by  on  03/11  at  01:26 PM
  13. ...start changing the laws of physics…

    Yes we can!

    In contrast to: ”<insert your physical law here> will only operate in a manner consistent with the president’s whim constitutional authority to supervise the unitary executive branch.”

    Posted by  on  03/11  at  01:45 PM
  14. Smashing (or banging? crunching?) good fun, Michael.  Unfortunately, I too already beat you to the punch.  You see, I reviewed this book last week, in the Dark Matter Review.  Here, I’ll cut and paste the review below:

    And here’s my German translation:

    Vielen Dank, Michael, und bis spater!

    Posted by Derek T.  on  03/11  at  02:57 PM
  15. Couple of mistakes in your German translation there, Derek.

    Instead of “ “, and “ “, and “ “, you should have written “ “.

    It’s all one word in german wink

    Posted by Eunoia  on  03/11  at  03:08 PM
  16. ?Tahw...Hu

    Posted by  on  03/11  at  03:29 PM
  17. Is that a formatting problem with the universe?

    Posted by Bob In Pacifca  on  03/11  at  04:03 PM
  18. The Big Bang! “But I can say that From Eternity to Here will have been a richly rewarding reading experience, even by the exacting standards of the genre, for everyone willing to give it the time.”

    Hah!

    Very nicely done, though. Captcha: changes, as in “Plus ca changes, plus ca meme choses”

    Posted by  on  03/11  at  04:18 PM
  19. I wonder if Julian Barbour is going to write a review saying that Sean’s book doesn’t really exist.

    x-post at CV

    Posted by  on  03/11  at  04:24 PM
  20. Thanks for the review and let me just say that, being from Minnesota I am glad that I don’t live in that parallel universe where Frank Viola never pitched in the World Series.

    Posted by  on  03/11  at  05:14 PM
  21. Ach, Eunoia, good catch.  I was breaking into a dialect at one point...sometimes I find myself fragmenting words.  It’s either the fault of some emergent linguistic system (from some alternate reality that Carroll hasn’t even told us about) or because I studied German in Unterwasserkorbfleichtensbuerg.

    Posted by Derek T.  on  03/11  at  08:17 PM
  22. Ah...a fan of the “Crab Canon” dialogue from Douglas Hofstadter’s GODEL, ESCHER, BACH, are we?  wink

    Posted by  on  03/11  at  10:08 PM
  23. a fan of the “Crab Canon” dialogue

    Ah, now that takes me forward.

    Derek T., Eunoia, I appreciate the dark energy you bring to this thread.  But as I admitted @ 6, my German is really rudimentary—it’s a sprachspiel here and a wissenschaft there, and that’s about it.  So your argument about

    pretty much eludes me.

    Posted by Michael  on  03/11  at  10:39 PM
  24. I would hope that Sean’s efforts would help explain how before/after Paul died the Walrus created great music walking in and out of step.  That, and perhaps something about the King’s men putting the egg shells back together again after/before the omelet.  I do however doubt that there will be a physics explanation for the wave action phenomena enveloping Deborah Kerr and Burt Lancaster, or why Donna Reed became and then unbecame the hottest momma of the 50s (or whatever that may be in the other universes)?

    Posted by  on  03/12  at  06:40 AM
  25. Back in the day when I was more into beer and girlies, a noted Zen Master attempted to explain reality to me.  Time, he said, does not really exist.  All one can say about reality is that it simply is. Time is a product of our limited perception abilities.  Everything that was, is or will be already exists in one eternal NOW.  Thus, Aristotle’s buffoonery in trying to persuade us that a thing can not exist, and exist at the same time.  Indeed, absent the illusory notion of time, it can and does.  According to my Zen Master, the date of one’s birth and the date of one’s death exist simultaneously, now, and at the same time together forever.

    Hmmm, sez I.  What the f**k do Zen Masters know? But if he’s correct, I’m gonna go find me some eternal titties

    Posted by  on  03/12  at  09:02 AM
  26. Miles Davis will do it before Cyndi Lauper?

    Yes, and only then will Chet Baker get around to doing the ultimate version of the Cahn/Styne standard, still unwritten.

    Posted by  on  03/12  at  10:55 AM
  27. Unfortunately you did not include the fact that some of the ideas are far outside the mainstream of physics.  Sean seems to have a thing for ‘Boltzmann Brains’ for example, a notion that is - quite frankly - ridiculed by the majority of most physicists working in the field.  Not because it’s a hot new concept whipped up by a young Turk, but because it betrays a rather fundamental misunderstanding of probability.

    I’m all for popular books to entice the lay public.  But even if their purpose is to dazzle as well as to edify, they should also be an accurate accounting of what’s going on[1].  ‘The Dancing Wu Li Masters’ may have been a best-selling bit of pop exposition; every physicist I know loathes it for it’s monumental inaccuracies.  Let’s not flood the market with woo-woo or Big But Wrong Ideas, eh?

    [1]Not having a copy of the book, I don’t know if the author takes any pains to point out that what he advocates is decidedly a minority view, for traditional majoritarian reasons about the nature of probability and statistics.  I have no objection to writers who clearly note these sorts of differences in the body of the text.

    Posted by  on  03/12  at  11:01 AM
  28. I’m gonna go find me some eternal titties

    That would be Montana Wildhack, wouldn’t it? In a punctual way of speaking.

    Posted by  on  03/12  at  11:15 AM
  29. Scent,

    I think if you were to read Sean’s existing writings/position on Boltzmann Brains you might come away with a different opinion.

    e.

    Posted by  on  03/12  at  01:58 PM
  30. Yo, JP Stormcrow:

    Re the fillum, I am certain that Vonnnegut woulda, did, will approve(d) of Valerie’s bazoobs.  In terms of a timeless eternity, well, she’ll do, in a present, eternal, now way of speaking.

    Posted by  on  03/12  at  04:54 PM
  31. Thank you for clearing up the confusion I have felt on this subject.

    Posted by Hattie  on  03/12  at  07:45 PM
  32. As a member in good standing of the above-mentioned “stoner” tribe, allow me to say: duuuuuuuuuude. This post blew my mind.

    Posted by Austin Dewby  on  03/12  at  07:55 PM
  33. In the future, I would have been meaning to learn Tralfamadorian. Then I spoke fine without regard to time and its (non)passing. Am I was?

    Posted by Jason B.  on  03/12  at  08:08 PM
  34. Can one find eternal titties and beer by hanging out with Sissy Hankshaw in one of the vertices betwixt universes??? She could help us get a ride.

    Posted by  on  03/13  at  05:16 AM
  35. it is boggling my mind, this mind-boggling blogging...after third read-thru realized time is indeed a circle

    Posted by mark  on  03/13  at  08:49 AM
  36. Thumbs up on that one Spyder.

    Posted by  on  03/13  at  09:30 AM
  37. All I have is time and time and tide are on my side.

    captcha “evidence” as in, there isn’t any

    Posted by  on  03/13  at  10:00 AM
  38. Ha ha, yes, very droll.  This post will have been worth every penny.  Though a tie-in with Dr. Manhattan would have been pure comedy gold.

    they patted my head and told me that because the Big Bang initiated all space and time, there was no such thing as “before the Big Bang.”

    Yeah, I remember that “Bloom County” strip well.

    To put this another way, you know you’re in difficult straits when you hear a physicist say that our standard conception of the Big Bang relies on “classical general relativity,” because when physicists say “classical,” they mean “quaint.”

    Well, until “M-theory,” or whatever the latest polydimensional “Bolts in my brane” nonsense is, can come up with any meaningful agreement with observation to compare with explaining the precession of Mercury’s perihelion, I’ll take such dismissal with a Planck volume of salt.

    But I’ll second Mr. Tarabour, ScentOfViolets.  Professor Carroll in fact does not accept the “Boltzmann brain” explanation, but introduces it as a superficially plausible attempt to explain time’s arrow, only to demolish it.

    it’s a sprachspiel here and a wissenschaft there

    Great, now I’m hungry.

    Posted by  on  03/13  at  10:12 AM
  39. I’m sorry, but that is simply not true.  Yes, I am acquainted with Sean’s views on the subject, and yes I’ve spoken with him personally.  And yes, I know a little something about statistical mechanics - my handle, ScentOfViolets, is in reference to a problem Boltzmann worked on in fact.

    So I can confidently say that Sean has this rather bizarre idea that Boltzmann Brains are far more likely than what we actually observe.  And it is this ‘fact’ that he uses to ‘demolish’ the idea that the universe arose from a statistical fluctuation.  That is probably what you are thinking of, mds.

    I can also confidently say that this notion of the relative frequency of Boltzmann Brains is a minority viewpoint.  Most physicists are skeptical of the reasoning, pointing out that a) there really isn’t a good way to ‘count’ the accessible states and b)the counting that is being used to justify the reasoning is using built-in and unjustified assumptions.  The general feeling in the community, in short, is that this is really just a rather shoddy use of the Anthropic Principle.  This is especially significant given that the use of this principle has come back to bite string theorists more than once; invoking it yet again seems to be something of a sore point with them.

    Now, I don’t mind speculation at all.  But I do insist that if one is writing a book to inform the general public that one should clearly label speculation - in particular, speculation that is felt by the physics community at large to be wrong-footed - as speculation.  I’ll admit that writing about string theory is rather problematic in this respect grin

    Posted by  on  03/13  at  11:30 AM
  40. Hurm.  I finally get it, SOV.  You disagree with the argument that the statistical fluctuation origin hypothesis makes BBs so much more likely.  If this is the case, the disagreement becomes more comprehensible, for sufficiently loose values of “comprehensible.”

    Meanwhile, I’m glad to have read that Professor Bérubé apparently had a relaxing hotel stay in the vicinity of my grandfather’s scandalously leftist alma mater.  I’m more curious how the latest in a long series of trips to New Haven went.  Humph.

    Posted by  on  03/13  at  01:49 PM
  41. Well, no, it’s not that I ‘disagree’ with it - it’s that most people in physics community disagree with it.  For the reasons I described.  Surely I stressed this point?  Looking up above, yes, I see that I did.

    Yes, if J. Random Blogger disagrees with someone in the area of their specialty, that’s pretty small potatoes.  I agree completely.  It’s when that someone operating out of a specialty takes a position at variance with most of those in his community that the matter bears remarking upon.

    And again, I don’t mind speculation in the slightest.  I just want it to be clearly labelled as speculation and a definite minority position in the field.

    This doesn’t seem to me to be a terribly controversial opinion.  What do you find so outlandish about it?  Do you disagree that controversial opinions in a given subject ought to be labelled as such for a lay reader?

    Would any other science writers care to comment?

    Posted by  on  03/13  at  08:31 PM
  42. SOV,

    Not that it matters, but I strongly suspect that Sean understands the difference between speculative and mainstream ideas and will be clear about those differences in the book. I believe he knows that he has a special responsibility to the lay reader not to mislead about what is the current consensus view and where he may or may not steer the conversation into speculative areas, I believe it will be clearly labeled as such. (if it hasn’t already been so labeled wink)

    e.

    Posted by  on  03/13  at  09:51 PM
  43. I suppose it won’t help matters any if I insist that I see Boltzmann Brains forming around me all the time.  So I won’t.  But maybe, just maybe, someday Sean’s book will have answered the question of whether his Popular Explanation of Incomprehensible Physics will be more like The Dancing Wu Li Masters or Future Shock or What the Bleep Do We Know?

    I’m more curious how the latest in a long series of trips to New Haven went.  Humph.

    You could have met me at Union Station between 6:45 and 7:10 this morning, mds, as I waited for my train to DC—and waited in vain for you.  Humph.  I would have been at my best, too, because Jamie and I got in last night at 11:30 and then Janet had the bright idea of checking in on the UConn - Syracuse game.  Fifteen overtimes later, I realized I would be traveling on two hours of sleep. . . .

    Posted by Michael  on  03/13  at  10:16 PM
  44. It is true that people often behave differently online than they would otherwise, and I don’t see why Sean would be an exception.  I sincerely hope you’re right grin

    Posted by  on  03/13  at  10:20 PM
  45. These first few months of 2009 have been hectic, with little time to keep abreast of the Bérubéosphere-- have I missed much?

    Oh, never mind… time for a fresh start.

    Posted by  on  03/14  at  12:49 AM
  46. There’s an argument that quantum gravity requires the wavefunction of the expanding universe to go to 0 at the turnaround point, so that the Big Crunch is in fact inaccessible.  Instead, physics justs slooooowwwwwwwsssssssss ddddddooooowwwwwwnnnnn aaaanddddddd sssttttttoooooooppppppppppppsssssssssssssssssss..............

    Posted by  on  03/14  at  12:40 PM
  47. Let us all hope that President Obama chooses his Boltzmann Brain czar very, very carefully.

    Posted by  on  03/14  at  04:03 PM
  48. I don’t think it’s that big a deal, Sven.  Word is that Obama will give his BB czar a Cabinet-level position, but only for a nanosecond.

    Captcha:  science.

    Posted by Michael  on  03/14  at  09:46 PM
  49. I was the less likely fluctuation slain
    By the false allure of the Boltzmann brain;
    But I was the smudge of an actual world—and I
    Lived on, grew on, for the by and by.

    Posted by  on  03/15  at  11:02 AM
  50. I’m really starting to appreciate the value of the review as a yet unwritten book. It allows for several orders of magnitude greater speculations and/or interpretations of what is/isn’t in the book.

    Posted by  on  03/15  at  03:35 PM
  51. Michael—glad to see you’re finally reading some good stuff.  Happy belated pi day (3/14).

    Your favorite left winger and physicist—Jim.

    By the way, I think people are so unaware of what a right winger you are on the ice.

    Posted by Jim Leous  on  03/15  at  03:45 PM
  52. I think people are so unaware of what a right winger you are on the ice.

    All right, Jim, I admit it:  I believe I should not be taxed punitively simply because I work hard in front of the other team’s net.  And I believe in a strong defense—provided entirely by people other than myself. If that makes me a “right” “winger,” so be it.

    And I finally read that “Crab Canon” thing!  Yes, I think I see the structural similarity in places.  Of course, in other universes, I could be influenced by Hofstadter before I read him--

    Posted by Michael  on  03/15  at  10:02 PM
  53. Obama will give his BB czar a Cabinet-level position, but only for a nanosecond.

    In that case, I will nominate Sean Carroll. Or did I?

    Posted by  on  03/15  at  10:18 PM
  54. In the past *everyone* will have had their 15 nanoseconds of czardom.

    Posted by  on  03/15  at  11:14 PM
  55. Okay, this is really pretty damn weird; the captcha is “Time,” wtf??  Especially since i was thinking of being less snarky and satirical in this moment.  Well, now there is now choice but to proceed.  Damn you Berube!

    “So, the following is from a documentary script i wrote in 1974 after a trip visiting the Southwest pueblos and reservations:”
    This creature with such a voice, informed me that he was a sea otter from the West, and he was to show me the ways of that direction, so that i would know them. He brought to me old lady who was a rug maker. She began to weave a rug.  As the rug took shape, she grew younger and then began her story. It was now quite light again, and I could see very clearly as she wove her rug, teaching me, through the otter, the circle of the West.  She revealed to me that each stitch of the rug has, in its nature the existence of the whole rug.

    Without that one stitch, in any one place, the rug would not be whole, nor would the rug be the same.  For all time, that stitch exists as does the rug. Even when the wool that made that stitch was just growing on the sheep, when the sheep was born, the existence of the rug and that stitch was inherent in that wool.  And should the rug be burned and the ashes scattered, the existence of the rug and that stitch remain eternal in the scattered ashes. Likewise, the sea otter and the mountains and all things live in each moment of the present. The glacier that carved the mountains always is carving them, carrying their matter to the sea, as are the mountains always as they are now.  All things that are, are the unity of the universe, are related in this manner. The way of the West is to look inside your self and see this and see how this relates to everything.

    Posted by  on  03/15  at  11:28 PM
  56. <...sigh...>

    Sometimes “droll” is *too* droll.

    Posted by  on  03/16  at  10:35 AM
  57. It’s a fine line between droll and too droll.  (And then there’s “concern droll,” another matter altogether.)

    I’m really starting to appreciate the value of the review as a yet unwritten book. It allows for several orders of magnitude greater speculations and/or interpretations of what is/isn’t in the book.

    Actually, Elliot, a survey of the responses to What’s Liberal three years ago suggests that the publication of a book is no barrier to speculations and/or interpretations of what is/isn’t in the book.  I especially liked the Amazon reviewer who insisted that the Foundation for Individual Rights in Education wasn’t in the index, and the Amazon reviewer who complained that I wouldn’t teach dead white guys because it’s not PC.

    Posted by Michael  on  03/16  at  11:45 AM
  58. I won’t teach dead white guys because their in-class participation is terrible. Take that, PC thought police!

    Posted by  on  03/16  at  12:10 PM
  59. I would hope that Sean’s efforts would help explain how before/after Paul died the Walrus created great music

    Here’s another clue for everyone
    The Walrus was really John . . .

    No, really--look for yourself:

    1.jpg

    Posted by  on  03/16  at  12:34 PM
  60. I won’t teach dead white guys because their in-class participation is terrible.

    Oh, come now, they can’t be that much worse than engineering students in intro physics.

    You could have met me at Union Station between 6:45 and 7:10 this morning, mds, as I waited for my train to DC—and waited in vain for you.  Humph.

    Wait, that was you?  Your head is much less ginormous and ghostly in real life.  Next time I’ll make eye contact rather than burying myself in the latest People’s Weekly World.

    And plaudits are due for that grueling 6-overtime victory to the “Somewhere West of Syracuse” Orange.

    Posted by  on  03/16  at  01:17 PM
  61. Boltzmann’s walruses
    fairly common occurrence
    or speculation

    Posted by  on  03/16  at  04:01 PM
  62. Well, i do notice the chorus of zombied dead white guys behind the furry ones above, which can only harken to a time warp again (captcha). 

    And not speaking of time in the future as a means to reducing something to the past: according to the large (5’+) letters on the concrete-block house across the street (nothing like those concrete-block bunkers, eh?), it will be blown up at 1PM on April 4th.  At the moment, they are extracting all of the plumbing pipes and electrical wire.  From elemental form back to elemental form.

    Posted by  on  03/16  at  04:31 PM
  63. the real question is when you’re going to review horowitz’s new book. i’ll have the popcorn ready!

    Posted by  on  03/16  at  09:23 PM
  64. Actually, Elliott, why not go whole hog; why stop at Boltzmann Brains?  Why not just adopt Egan’s hypothesis and say that all we are is dust?  That takes care of everything at one go, including the problem of time grin That wouldn’t be too speculative, would it?

    Posted by  on  03/17  at  10:41 AM
  65. Why not just adopt Egan’s hypothesis and say that all we are is dust?

    Since Egan was admittedly mostly horsing around with the concept, how about going with either Moravec or Tegmark?  (Just a reminder of how much speculation goes on beyond Carroll’s if/then involving the statistical fluctuation origin hypothesis.)

    Stochastic process
    Seems to us to be causal
    But we are mere dust.

    Posted by  on  03/17  at  04:22 PM
  66. Egan’s?
    egads!

    Posted by  on  03/18  at  01:11 AM
  67. Elliot, I get the distinct impression that you are, shall we say, slightly partisan wink Most people I know were first exposed to the dust theory via Egan, not Moravec.  Just as most singularity fans got their information from Kurzweil, and not someone like Good(s?).

    Since you apparently don’t know just how ‘speculative’ Sean’s methods are of counting, would it be to much to ask that you withhold your opinion until you do some research?  Really, this is quite standard material.  I had assumed you were some sort of physicist or perhaps a mathematician.

    Posted by  on  03/19  at  10:26 AM
  68. Oh, ScentOfViolets, this is supposed to be a fun place, albeit with sprinkles of snark.  Crooked Timber is the place to get into a rhubarb with worthies such as John Emerson, who apparently blames particle theorists for killing his dog.

    So, instead of getting brusque with one another about just how much Professor Carroll, e.g., overstrains elements from the DKS formalism (which I’ll admit that most of us are unable to rigorously evaluate), why don’t we stick to haikus and silly inside jokes?  Literary criticisms of Egan are also okay, for obvious reasons.  Really, the man does decent short stories, but is apparently completely unable to write good endings for novels.

    Hey, why did the cosmologists bring their baby to the conference?

    They couldn’t find de Sitter!

    Posted by  on  03/19  at  04:20 PM
  69. Well, gee, mds, why didn’t you say something about that Egan Egads snark.  You’re a day late and a dollar short with your criticism.

    But to show you that I’m a fair-minded guy, I’m willing to believe you’re sincere if you make that criticism now.  If you’re not . . .

    Posted by  on  03/19  at  06:12 PM

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