Travel

Peregrinations

Running around these days, doing some linear combination of actual work and talking about things. (Sometimes the talking leads to actual work, so it’s not a total loss.) If you happen to be in a sciencey kind of mood when I’m in your vicinity, feel free to come to a talk and say hi!

  • Today, if you happen to be in Walla Walla, Washington, I’ll be giving the Brattain lecture at Whitman College, on the Higgs boson and the hunt therefor.
  • Next week I’ll be in Austin, TX. On Thursday April 17, I’ll be speaking in the Distinguished Lecture Series, once again on the marvels of the Higgs.
  • In May I’ll be headed to the Big Apple twice. The first time will be on May 7 for an Intelligence Squared Debate. The subject will be “Is There Life After Death?” I’ll be saying no, and Steven Novella will be along there with me; our opponents will be Eben Alexander and Raymond Moody.
  • Then back home for a bit, and then back to NYC again, for the World Science Festival. I’ll be participating in a few events there between May 29 and 31, although precise spatio-temporal locations have yet to be completely determined. One will be about “Science and Story,” one will be a screening of Particle Fever, and one will be a book event.
  • I won’t even have a chance to return home from NYC before jetting to the UK for the Cheltenham Science Festival. Once again, participating in a few different events, all on June 3/4: something on Science and Hollywood, something on the Higgs, and something on the arrow of time. Check local listings!
  • A chance I will be in Oxford right after Cheltenham, but nothing’s settled yet.
  • That’s it. Looking forward to a glorious summer full of real productivity.

Peregrinations Read More »

8 Comments

Hither and Yon

Best intentions (put nose to the grindstone, get these papers finished) notwithstanding, I do have a few more public lectures and whatnot coming up over the next few weeks. Would love to see you there! And if not, I recently did an episode of the Rationally Speaking podcast with Massimo Pigliucci and Julia Galef, where we talked about naturalism, science, philosophy, and other things I’m marginally qualified to speak on.

Wednesday May 22: I’m giving a public talk on the arrow of time at UC Davis. This is in the midst of a conference on the early universe, which should also be fun.

Wednesday May 29: I’ll be talking with Jim Holt, author of Why Does the World Exist?, at the LA Public Library. It’s possible this is will be sold out, but I think they’re going to tape it.

Sunday June 2: I’m the keynote speaker at the American Humanist Society annual conference in San Diego. 10:30 a.m. on a Sunday, so this one might be easier to get into! In fact you can get in for free even if you didn’t register for the conference, by following these simple steps:

1. Go to the website here: http://ahacon13.eventbrite.com/#
2. Click the orange “Enter Promotional Code” link.
3. Enter FREECON in the field that appears and click Apply.
4. The list of items should then include the free “Free to the Public: Matt Harding & Sean Carroll” option.
5. Choose that one (and any others) and then complete the registration.

Thursday June 6: Opening night at the Seattle Science Festival features Brian Greene, Adam Frank, and me, under the stern but fair moderation of Jennifer Ouellette. Adam and I will give short talks, and Brian will show us the West Coast premiere of the multimedia performance Icarus at the Edge of Time.

Wednesday June 12: I’m giving a public lecture at Fermilab on particles, fields, and the future of physics. It’s part of the Fermilab Users’s Meeting, as well as a workshop on the International Linear Collider. Not sure if I’ve ever given a public talk that will have so many people ready to correct my mistakes.

After a couple more trips in July, my calendar actually does clear up, and I can look forward to uninterrupted vistas of productivity. Watch out!

Hither and Yon Read More »

8 Comments

Upgrading the Public Lecture Experience

Apologies for the extended radio silence here at the blog. (Originally typed “radio science,” which I suppose is an encouraging sign from my subconscious.) My time and attention has been taken up by an interesting phenomenon known as “real work.” I have four papers in almost-submittable rough draft form, another three projects bubbling along nicely, and one project in the “this result can’t be right because if it is right it would be really interesting and important and that never happens but hey you never know” stage. Feels good to be concentrating on research after a year with too much book writing, traveling, workshop organizing, etc.

Speaking of traveling, I spent last week in Australia, partly in Sydney and partly in Canberra. This trip owed its existence to two fortunate facts. First, back in graduate school my officemate was Brian Schmidt, who has since become an influential astronomer living in Australia (oh, and won the Nobel Prize for a little thing called the acceleration of the universe). Second, Brian and I like to make bets with each other, which I always win. (At least as of the current moment, with n=2.)

Our first bet, made back in grad school, was whether we would someday have a reliable measurement of Omega, the cosmological density parameter. We purchased a small bottle of vintage port and agreed that Brian would collect it if we didn’t have an agreed-upon value within 20 years, while I would collect it if we did. You have to remember that back in early 90’s, astronomers kept measuring numbers that implied the universe was open, while theorists kept insisting that it must be spatially flat on naturalness grounds. The controversy was largely ended by the discovery of cosmic acceleration, showing that both camps were right: astronomers had correctly measured the density of matter, but universe is essentially flat, the remainder being taken up by dark energy. Brian graciously conceded, but I’m sure King Carl Gustav consoled him on his defeat.

vineyard In 2009 Brian foolishly challenged me again, this time on whether physicists would eventually discover the Higgs boson at the LHC. His job is to play the curmudgeonly experimentalist, while I am the ever-optimistic theorist — so in July 2012, when CERN announced a new particle, Brian found himself once again in the role of gracious conceder. We’re all grown up by now, so the stakes were a bit larger: Brian donated some of his impressive store of frequent flyer miles to fly Jennifer and me to Australia, where I would give some talks. We had a great time, needless to say, including a visit to the vineyard where Brian makes his celebrated Maipenrai Pinot Noir. (Yes you read that correctly. He’s an energetic guy.)

But the real lesson I learned from the whole trip is: with a tiny amount of effort, it’s possible to turn the ordinary public lecture experience into something much more fun for the audience. …

Upgrading the Public Lecture Experience Read More »

16 Comments

Hello England!

Just a word to folks in the UK, I’ll be breezing through next week and the week after and giving a handful of talks. First up is a visit to Oxford, where I’m participating in a miniseries called “Is God Explanatory?” (Not really, I will point out.) The workshop proper includes me, philosophers Lara Buchak and John Hawthorne, and astronomer/theologian William Stoeger. The conference dinner on the 10th will feature brief talks by me and philosopher/theologian Keith Ward. I think it will all be interesting and useful discussion, largely free of sputtering and invective. While I’m there I hope to sneak in some chats about quantum mechanics and cosmology with the local physicists and philosophers. (Very sad I’ll be missing A Theory of Justice: The Musical.)

After that it’s off to London, where I will briefly pretend to be Michael Faraday and give a lecture at the Royal Institution. I’ll be talking about the Higgs boson. It’s a pretty new particle, you probably haven’t heard of it. </hipster>

Then it’s off to the wilds of Nottingham, where I’m giving both a colloquium on the 16th on the many-worlds interpretation of quantum mechanics, and a public lecture on the 17th. The latter is, you know, open to the public, so please stop by. (The colloquium is presumably also open, but it’s for folks who are already familiar with the basics of QM.)

Unless you already went to the RI lecture, in which case don’t bother, since they’re on the same topics. Seriously, even the jokes will be the same. The trick is to make it sound like I just thought them up.

Hello England! Read More »

20 Comments

Cosmology and Philosophy at La Pietra

I’ve traded off my reasons for not blogging much of late. Last week and before it was The Particle at the End of the Universe (in stores November 13!), but that’s now been handed in and I can kick back and catch up on my martini-drinking. Except that instead of doing that, I instantly hopped on a plane for Europe, where I’m now participating in a workshop on philosophy and cosmology. Not that you should feel sorry for me — the workshop is being held at the La Pietra conference center, a beautiful facility owned by NYU in Florence. I’m not sure why NYU owns a conference center in Florence; it could have been a targeted purchase, but it could easily have just been a gift. (Caltech for a while owned an abandoned gold mine. Universities get all sorts of crazy gifts.) But at least temporarily, martinis have been put aside for Chianti and limoncello.

And work, of course. This is my favorite kind of workshop: less than twenty people, gathered around a table, with no fixed agenda, talking about issues of mutual interest as they come up. This group has both scientists and philosophers, although probably more of the latter. So far each day has featured a scientist — Joel Primack, me, Brian Greene, Scott Aaronson — giving some very general remarks, while everyone else takes turns whacking them with (metaphorical) sticks. My own talk started at 11 a.m. and didn’t finish until 5:30 p.m., with breaks for lunch and coffee. So it’s exhausting both intellectually and physically, but very rewarding to have the chance to dig very deeply into difficult issues.

My talk was about — you guessed it — the arrow of time. Most people in the room are already familiar with the basic story that time’s arrow is (at least mostly) a consequence of the increase of entropy over time, and that our current universe has low entropy, but the entropy was even much lower in the past, and that last fact demands cosmological explanation. The central question concerned what would count as an “explanation.” …

Cosmology and Philosophy at La Pietra Read More »

26 Comments

Time Is Out of Joint

Greetings from Norway, where we’re about to embark on what is surely the most logistically elaborate conference I’ve ever attended. Setting Time Aright starts here in Norway, where we hop on a boat and cross the North Sea to Copenhagen. The get-together is sponsored by the Foundational Questions Institute, although it came together in an unusual way; I was part of a group that was organizing a conference, and we applied to FQXi for funding, at which point they mentioned they were planning almost exactly the same conference at the same time. So we joined forces, and here we are. Unity ’11!

The topic, if you haven’t guessed, is time. That’s a big subject, one that can hardly be done justice by sprawling books with hundreds of (admittedly quite charming) footnotes. You can see why the conference has to spread over two countries. We’re trying an experiment in interdisciplinarity: while the conference is a serious event meant for researchers, we have a wide variety of specialties represented, including biologists, computer scientists, philosophers, and neuroscientists, as well as the inevitable physicists and cosmologists. (There is also a public event, for those of you who find yourselves in Copenhagen next week.) I can’t wait to hear some of these talks, it should be a blast.

My job is to open the conference with an introductory talk that hits on some of the big questions. Here are the slides, at least as they are right now; last-minute editing is always a possibility. I think I put enough in there to provoke almost everyone at the conference one way or another.

Time Is Out of Joint Read More »

57 Comments

Greetings from Qatar

Not much blogging this week, as I’m at the World Conference of Science Journalists in Doha, Qatar. I’m informed that the technical term describing my role here is that of trailing spouse. But I did give a little talk on upcoming discoveries we should be looking forward to in particle physics and cosmology.

I’ll try to put up a more full report later. Right now I’ve just been guilted into blogging because I’m listening to a sexy and exciting panel about science blogs, staring Mo Costandi, Maryn McKenna, Jennifer Ouellette, Ed Yong, and Mohammed Yahia. And just to prove I’m here, I can show you what a sign inside Starbucks looks like in an Arab country.

Afterwards I’ll be headed to the souk to shop for scimitars.

Greetings from Qatar Read More »

8 Comments

Avignon Day 4: Dark Matter

Yesterday’s talks were devoted to the idea of dark matter, which as you know is the hottest topic in cosmology these days, both theoretically and experimentally.

Eric Armengaud and Lars Bergstrom gave updates on the state of direct searches and indirect searches for dark matter, respectively. John March-Russell gave a theory talk about possible connections between dark matter and the baryon asymmetry. The density of dark matter and ordinary matter in the universe is the same, to within an order of magnitude, even though we usually think of them as arising from completely different mechanisms. That’s a coincidence that bugs some people, and the last couple of years have seen a boomlet of papers proposing models in which the two phenomena are actually connected. Tracy Slatyer gave an update on proposals for a new dark force coupled to dark matter, which could give rise to interesting signatures in both direct and indirect detection experiments.

This is science at its most intense. A big, looming mystery, a bounty of clever theoretical ideas, not nearly enough data to pinpoint the correct answer, but more than enough data to exclude or tightly constrain most of the ideas you might have. It wouldn’t be at all surprising if we finally discover the dark matter in the next few years; unfortunately, it wouldn’t really be surprising if it eluded detection for a very long time. If we knew the answers ahead of time, it wouldn’t be science (or nearly as much fun).

Today is our last day in Avignon, devoted to cosmic acceleration. My own talk later today is on “White and Dark Smokes in Cosmology.” (The title wasn’t my idea, but I couldn’t have done better, given the context.) It’s the last talk of the conference, so I’ll try to take a big-picture perspective and not sweat the technical details, but (following tradition) I will admit that it’s an excuse to talk about my own recent papers and ideas I think are interesting but haven’t written papers about. At least it should be short, which I understand is the primary criterion for a successful talk of this type.

Also, few people have strong feelings about non-gaussianities or neutrinos, but many people have strong feelings about reductionism. Quelle surprise!

Avignon Day 4: Dark Matter Read More »

14 Comments

Avignon Day 3: Reductionism

Every academic who attends conferences knows that the best parts are not the formal presentations, but the informal interactions in between. Roughly speaking, the perfect conference would consist of about 10% talks and 90% coffee breaks; an explanation for why the ratio is reversed for almost every real conference is left as an exercise for the reader.

Yesterday’s talks here in Avignon constituted a great overview of issues in cosmological structure formation. But my favorite part was the conversation at our table at the conference banquet, fueled by a pretty darn good Côtes du Rhône. After a long day of hardcore data-driven science, our attention wandered to deep issues about fundamental physics: is the entire history of the universe determined by the exact physical state at any one moment in time?

The answer, by the way, is “yes.” At least I think so. This certainly would be the case is classical Newtonian physics, and it’s also the case in the many-worlds interpretation of quantum mechanics, which is how we got onto the topic. In MWI, the entirety of dynamics is encapsulated in the Schrodinger equation, a first-order differential equation that uniquely determines the quantum state in the past and future from the state at the present time. If you believe that wave functions really collapse, determinism is obviously lost; prediction is necessarily probabilistic, and retrodiction is effectively impossible.

But there was a contingent of physicists at our table who were willing to believe in MWI, but nevertheless didn’t believe that the laws of microscopic quantum mechanics were sufficient to describe the evolution of the universe. They were taking an anti-reductionist line: complex systems like people and proteins and planets couldn’t be described simply by the Standard Model of particle physics applied to a large number of particles, but instead called for some sort of autonomous description appropriate at macroscopic scales.

No one denies that in practice we can never describe human beings as collections of electrons, protons, and neutrons obeying the Schrodinger equation. But many of us think that this is clearly an issue of practice vs. principle; the ability of our finite minds to collect the relevant data and solve the relevant equations shouldn’t be taken as evidence that the universe isn’t fully capable of doing so.

Yet, that is what they were arguing — that there was no useful sense in which something as complicated as a person could, even in principle, be described as a collection of elementary particles obeying the laws of microscopic physics. This is an extremely dramatic ontological claim, and I have almost no doubt whatsoever that it’s incorrect — but I have to admit that I can’t put my objections into a compact and persuasive form. I’m trying to rise above responding with a blank stare and “you can’t be serious.”

So, that’s a shortcoming on my part, and I need to clean up my act. Why shouldn’t we expect truly new laws of behavior at different scales? (Note: not just that we can’t derive the higher-level laws from the lower-level ones, but that the higher-level laws aren’t even necessarily consistent with the lower-level ones.) My best argument is simply that: (1) that’s an incredibly complicated and inelegant way to run a universe, and (2) there’s absolutely no evidence for it. (Either argument separately wouldn’t be that persuasive, but together they carry some weight.) Of course it’s difficult to describe people using Schrodinger’s equation, but that’s not evidence that our behavior is actually incompatible with a reductionist description. To believe otherwise you have to believe that somewhere along the progression from particles to atoms to molecules to proteins to cells to organisms, physical systems begin to violate the microscopic laws of physics. At what point is that supposed to happen? And what evidence is there supposed to be?

But I don’t think my incredulity will suffice to sway the opinion of anyone who is otherwise inclined, so I have to polish up the justification for my side of the argument. My banquet table was full of particle physicists and cosmologists — pretty much the most sympathetic audience for reductionism one can possibly imagine. If I can’t convince them, there’s not much hope for the rest of the world.

Avignon Day 3: Reductionism Read More »

92 Comments
Scroll to Top