A Universe from Nothing?

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Some of you may have been following a tiny brouhaha (“kerfuffle” is so overused, don’t you think?) that has sprung up around the question of why the universe exists. You can’t say we think small around here.

First Lawrence Krauss came out with a new book, A Universe From Nothing: Why There Is Something Rather Than Nothing (based in part on a popular YouTube lecture), which addresses this question from the point of view of a modern cosmologist. Then David Albert, speaking as a modern philosopher of science, came out with quite a negative review of the book in the New York Times. And discussion has gone back and forth since then: here’s Jerry Coyne (mostly siding with Albert), the Rutgers Philosophy of Cosmology blog (with interesting voices in the comments), a long interview with Krauss in the Atlantic, comments by Massimo Pigliucci, and another response by Krauss on the Scientific American site.

I’ve been meaning to chime in, for personal as well as scientific reasons. I do work on the origin of the universe, after all, and both Lawrence and David are friends of the blog (and of me): Lawrence was our first guest-blogger, and David and I did Bloggingheads dialogues here and here.

Executive summary

This is going to be kind of long, so here’s the upshot. Very roughly, there are two different kinds of questions lurking around the issue of “Why is there something rather than nothing?” One question is, within some framework of physical laws that is flexible enough to allow for the possible existence of either “stuff” or “no stuff” (where “stuff” might include space and time itself), why does the actual manifestation of reality seem to feature all this stuff? The other is, why do we have this particular framework of physical law, or even something called “physical law” at all? Lawrence (again, roughly) addresses the first question, and David cares about the second, and both sides expend a lot of energy insisting that their question is the “right” one rather than just admitting they are different questions. Nothing about modern physics explains why we have these laws rather than some totally different laws, although physicists sometimes talk that way — a mistake they might be able to avoid if they took philosophers more seriously. Then the discussion quickly degrades into name-calling and point-missing, which is unfortunate because these are smart people who agree about 95% of the interesting issues, and the chance for productive engagement diminishes considerably with each installment.

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The Particle At the End of the Universe

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Update: here’s the amazon page, where the book is ready for pre-order.

Speaking of writing popular books, I’m at it again. I’m currently hard at work writing The Particle At the End of the Universe, a popular-level book on the Large Hadron Collider and the search for the Higgs boson. If all goes well, it should appear in bookstores at the end of this year or beginning of next. (Ideally, it will go on sale the same day they announce the discovery of the Higgs. I’m trying to bribe the right people to make that happen.) The title is somewhat tentative, so it might change at some point.

This will be a somewhat different book than From Eternity to Here. While both are aimed at a general audience, FETH was a rather lengthy tome that made a careful argument in a hopefully novel way. Anyone could read it, but to get the most out of it you have to really sit and think about certain ideas. Particle, on the other hand, aims to be a fun and narratively gripping page-turner — a book that makes you eager to move quickly to the next chapter, rather than taking a few minutes to let the last one sink into your head. A bodice-ripper, if you will. It will be full of stories and fun anecdotes about the human beings who made the LHC happen and have devoted their lives to searching for the Higgs and particles beyond the Standard Model. A book you would be happy to give to your Grandmom in order to convey some of the excitement of modern physics. (Unless your Grandmom is a particle physicist, in which case she might think it’s at too low a level.)

At the same time, of course, I’m going to try to illuminate the central ideas of the Standard Model in as clear a fashion as I can manage. It won’t just be a list of particles; I’ll cover field theory, gauge bosons, and spontaneous symmetry breaking. All in fine bodice-ripping style. (Maybe get Fabio for the cover?)

If you are a particle physicist yourself, I’m happy to take input. This could take the form of a favorite analogy you like to use to explain some subtle concept, or some physics idea or piece of history you think really doesn’t get the attention it deserves in the popular media. Even better if you have some personal involvement in a fun story — you lost your virginity in the LHC tunnel, or you discovered asymptotic freedom but didn’t get around to publishing it. I’m talking to as many physicists as I can, but I can’t talk to everyone. I’m looking for tales that will make the human side of physics come alive.

Also happy to take input if you’re not a particle physicist! What are the concepts that we don’t do a good job explaining? What are the buzzwords you’ve heard about the don’t make sense? The questions you really want answered?

I sincerely believe the search for the Higgs and whatever might lie beyond is a Big Deal in the history of science, and I hope to convey some of the importance and excitement of this question to as large an audience as possible. I’ll be flitting around the country giving talks when the book comes out, so let me know if you have a big lecture hall full of eager minds that want to hear the latest dispatches from the particle trenches. Should be a fun ride.

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Aiming at Different Audiences

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When I wrote From Eternity to Here, I was faced with a perennial problem for pop-physics authors: how to write a book that will appeal to the aficionados (although not scientists themselves) who have already devoured everything Brian Greene and Lisa Randall have ever written, but also be understandable and interesting to folks who don’t know much more about Einstein than the fact that he rarely combed his hair? I came across a short blog review that claims I wasn’t entirely successful in balancing the competing requirements, and it might be a fair criticism.

But one small complaint is I’m not sure if he’s quite exactly worked out his audience. Early in the book, I was starting to fear it would be a rehash of stuff I already knew. It’s not. But there were some elementary rehashes that, frankly, I think if someone went into the book not having that knowledge already, they aren’t going to be able to grok the rest. This is not a mathematically demanding book, but it is a conceptually demanding book, and I am not sure if someone who doesn’t have some limited grounding in the mathematics side will be able to make it through the conceptual side without missing a lot.

The diagnosis is completely accurate. On the one hand, I do spend time going over the basics of relativity, quantum mechanics, and logarithms, in ways that hopefully make these ideas accessible to people who haven’t ever tried to understand them before. On the other hand, the meaty middle section of the book is conceptually very challenging for almost everybody, even if you are a regular consumer of popular physics books. We are simply not used to thinking in ways that don’t presume the arrow of time from the start, and some of the issues that arise are highly non-intuitive. I tried to keep things fun and engaging, but there’s no question that certain pages of the book require careful thinking and brain work.

What to do? I’m not sure that, given the material I wanted to cover in this book, there is much else one could do. Probably I could have had less about the basics of relativity, and moved what there is until later in the book. But although the central ideas are conceptually very challenging, I don’t think they’re actually inaccessible to anyone who is willing to put some thought into them, regardless of mathematical background. So I don’t regret that I didn’t write a leaner and more challenging book aimed only at the aficionados, although I appreciate that something along those lines might have been more focused. I think that the aficionados just have to get used to reading introductions to GR and QM from a wide variety of different books — at least until those topics become part of the standard high-school curriculum.

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Puzzles!

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Science keeps advancing, in fits and starts. It was a good week for intriguing results from experiments.

The first bit of news, which has been the subject of the most internet buzz, is a new paper by Chilean astronomers C. Moni Bidin, G. Carraro, R. A. Mendez, and R. Smith, which claims that there’s no evidence for dark matter in the dynamics of stars near the Sun. If this were true, it would imply something funny going on with the distribution of nearby dark matter, which could have significant implications for direct searches here on Earth (see below). It wouldn’t really be much of a threat to the idea of dark matter itself, since there’s plenty of evidence for dark matter elsewhere. But it might mean that the distribution in the Milky Way was very different from the kinds of models we like to use, for example by being much lumpier.

We just heard a great physics colloquium here at Caltech by Katie Freese, who talked about this result very briefly. Her opinion matched those of the skeptics in Ron Cowen’s article linked above: this paper makes a lot of assumptions, some of the a bit dubious, and we would need to see something much more solid before we become convinced. The biggest issue is that they don’t actually measure the DM distribution near the Sun; they try to measure it in a region between 1500 and 4000 parsecs below the galactic plane (which is actually pretty far away), and then fit to a model and extrapolate to what we should have nearby. …

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Jon Stewart Doesn’t Understand How Science Works Even a Little Bit

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I love Jon Stewart’s work on The Daily Show, which manages to be consistently fresh and intelligent. Their segment on the Large Hadron Collider was sheer brilliance, and I’ve often said that between Stewart and Stephen Colbert, Comedy Central is the best place to go to hear insights from real working scientists on TV these days.

Which is why it was so crushing to listen to this interview he did with Marilynne Robinson, a leader among the movement to reconcile science and religion. I didn’t agree with much of what Robinson said, but then again I didn’t really expect to. Nor did I expect Stewart to challenge her in any way; a “why just can’t we all get along” perspective is very consistent with his way of thinking. But I admit I was hoping he would not misrepresent modern science as thoroughly and lazily as he managed to do here. (It’s a 2010 interview, brought to my attention by Scott Derrickson’s Twitter feed; apologies if these complaints were hashed out elsewhere two years ago.)

The Daily Show with Jon Stewart Mon – Thurs 11p / 10c
Marilynne Robinson
www.thedailyshow.com
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If you skip ahead to 2:50, here’s what Stewart has to say: …

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Is Physics Among the Dysfunctional Sciences?

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Sorry for a post title that will attract the crazies. Carl Zimmer has a story in the New York Times that discusses a growing unease with the practice of science among scientists themselves.

In tomorrow’s New York Times, I’ve got a long story about a growing sense among scientists that science itself is getting dysfunctional. For them, the clearest sign of this dysfunction is the growing rate of retractions of scientific papers, either due to errors or due to misconduct. But retractions represent just the most obvious symptom of deep institutional problems with how science is done these days–how projects get funded, how scientists find jobs, and how they keep labs up and running.

However… essentially all the examples are from biologically-oriented fields. I’ll confess that Carl asked me if there is a similar feeling among physicists, and after some thought I decide that there really isn’t. There are certainly fumbles (faster-than-light neutrinos, anyone?) and scandals (Jan Hendrik Schön being the most obvious), but I don’t have any feeling that the problem is growing in a noticeable way. Biology and physics are fundamentally different, especially because of the tremendous pressure within medical sciences when it comes to any results that might turn out to be medically useful. Cosmologists certainly don’t have to worry about that.

But maybe this is a distorted view from within my personal bubble? Happy to hear informed opinion to the contrary. The relevant kind of informed opinion would actually involve a comparison of the situation today with the situation at some previous time, not just a litany of things you think are dysfunctional about the present day.

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Quantum Mechanics and Decision Theory

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Several different things (all pleasant and work-related, no disasters) have been keeping me from being a good blogger as of late. Last week, for example, we hosted a visit by Andy Albrecht from UC Davis. Andy is one of the pioneers of inflation, and these days has been thinking about the foundations of cosmology, which brings you smack up against other foundational issues in fields like statistical mechanics and quantum mechanics. We spent a lot of time talking about the nature of probability in QM, sparked in part by a somewhat-recent paper by our erstwhile guest blogger Don Page.

But that’s not what I want to talk about right now. Rather, our conversations nudged me into investigating some work that I have long known about but never really looked into: David Deutsch’s argument that probability in quantum mechanics doesn’t arise as part of a separate ad hoc assumption, but can be justified using decision theory. (Which led me to this weekend’s provocative quote.) Deutsch’s work (and subsequent refinements by another former guest blogger, David Wallace) is known to everyone who thinks about the foundations of quantum mechanics, but for some reason I had never sat down and read his paper. Now I have, and I think the basic idea is simple enough to put in a blog post — at least, a blog post aimed at people who are already familiar with the basics of quantum mechanics. (I don’t have the energy in me for a true popularization at the moment.) I’m going to try to get to the essence of the argument rather than being completely careful, so please see the original paper for the details.

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