If you happen to be the sort to follow a few cosmologists on blogs or social media, you've probably seen rumors swirling around like mad for the past few days. I'm not sure if this was triggered by the Harvard press release promising that a "major discovery" in astrophysics would be announced Monday at noon, or whether that release was hurried out the door only after the rumors got out. But it sounds like it could be a Big Deal, so keep your eyes open tomorrow. (One rumor is that they've invited Guth and Linde, the first theorists to propose cosmic inflation, to attend the announcement.)

Probably the best description I've seen of what people think the press conference is going to be about came from my friend Sean Carroll at Caltech: it seems that an experimental group observing the Cosmic Microwave Background is going to announce that they have seen direct evidence of perturbations of that background caused by gravitational waves in the first instants of the Big Bang. (As Sean explains, today our direct experimental data on the early universe extends back to about one second after the start of the Big Bang. This observation would push that back to an astounding 10^-35 seconds after the start.)

I won't try to explain the physics here, since it's really not my specialty. The intriguing thing is that, as far as I can tell, most people were not expecting to see any actual detection of this signal from the current generation of experiments: other data suggested that the current experiments would only be able to set "less than this threshold" sorts of limits. So this impending announcement would seem to imply one of four things: 1) The signal is much stronger than expected, which would be Very Exciting(TM) for physics, 2) The experiment turned out to be more sensitive than expected, which would presumably involve either really good luck or some neat improvements in data analysis algorithms, 3) The announcement is merely of strongly suggestive evidence rather than a true discovery-level result, which would make the "major discovery" press conference seem quite overblown, or 4) Someone messed up their analysis and/or got fooled by a statistical fluctuation, which after all this hoopla would probably wind up ending multiple careers. (I can guarantee that the experimental team here is painfully aware of all these possibilities. But then, so were the folks who claimed to have seen neutrinos moving faster than light a few years back.)

So yeah. It sounds like the actual science talk will begin at 10:45 (with papers and data going online at the same time). So watch the news, or at least the blogs! It should be exciting.

Charged particles released after the big solar flare last week have been reaching the Earth all weekend, and there's a good chance of an impressive aurora tonight! (I probably ought to have said something yesterday...) There's a good Aurora Forecast page from the University of Alaska that will show you what to expect where. In fact, if it weren't sunny right now, their Short Term forecast map seems to imply that auroral activity would likely be happening right over Michigan (and Montana and Maine and possibly even farther south than that) and that it might even be visible on the horizon as far south as New Orleans. Who knows whether it will be anything like that tonight, but try to have a look!

Wednesday may prove to be a very exciting day in physics: the two LHC teams searching for the Higgs boson are scheduled to give a seminar, and pretty much the entire particle physics community expects their announcement to amount to a discovery (though either experiment on its own may or may not pass the official threshold this time). This is a Big Deal: finding the Higgs was one of the primary goals of the LHC (perhaps the primary goal), and it's the very last piece of the Standard Model of particle physics whose existence has not yet been confirmed. These groups presented some very tantalizing evidence last December, but now that they've taken more data we may finally be there for real.

The really interesting thing to watch for in this announcement is whether the particle they're seeing seems to behave exactly as the Standard Model predicts, or whether its interactions are different in some subtle way. Most of us really, really hope that there are differences, because the behavior of the Higgs is sensitive to many types of "new physics": it could give us the first fundamentally new experimental evidence about the ultimate laws of nature that we've had in a decade (or maybe even three decades or more, depending on what you count as "new" and how narrowly you focus on particle physics). Nobody expects tomorrow's announcement to make solid claims about any of that: it will take years of data to really start to understand the details. But December's data seemed to have weak hints of something unexpected, so people will be watching carefully to see whether those hints get stronger or whether they fade away as the statistics improve.

I'll presumably post something all excited in the morning. But if you're interested, keep an eye on Cosmic Variance or your favorite particle physics blog for news. The seminar is at 9am in Geneva, so that's 3am Eastern. I expect to be envious of everyone on the west coast who gets to see the results live at midnight!

Last December, the LHC experiments from CERN looking for the Higgs boson announced some pretty promising evidence that they had started to see it, and had measured its mass-energy at about 125 GeV. It wasn't clear enough to claim a true "discovery" yet, but it was promising. Today, scientists from Fermilab presented analysis of some of the last data collected before the Tevatron shut down (along with some improved analysis of their years of previous data), and they found evidence consistent with what the LHC saw. It's not as strong as the LHC signal was, but that's expected because their accelerator isn't as powerful. But the fact that two entirely separate machines have produced results that agree is an awfully good sign that this is the real thing. If you want to read some details, I heard about this from blog posts here and here.

The worrisome thing right now is that we're awfully close to the "nightmare" scenario for data from the LHC: finding the Higgs but not finding any evidence at all of physics beyond the Standard Model. All of the searches for things like extra dimensions and supersymmetry have thus far found nothing, even though the most natural supersymmetry models would quite likely have started to give strong hints by now. (Those ideas all have lots of variations and thus aren't remotely close to being ruled out yet, but it's getting harder to believe in the variations that got people excited about them in the first place.) If we find the Higgs, then that means the Standard Model is complete and internally consistent... as far as it goes. But we also know that the Standard Model can't be the whole story: its math simply isn't capable of being a "final" theory of nature. (For example, on its own it predicts effects that would make us measure the Higgs mass to be infinite! And of course it's ultimately incapable of coexisting with a universe that contains gravity, but that's true of any quantum field theory.) So it would be Really Unpleasant to have (on some level) finished studying the particle physics that we've already known for thirty years without the slightest hint of what the next step ought to be.

But still: finding the Higgs is really exciting, and there's plenty of time to worry about future prospects later.

My name (including its weird spelling) has been in my family for generations. My father is Walter Steuard Jensen, Jr., son of Walter Steuard Jensen, son of Walter ??? Jensen, son of Steuard Raun Jensen who came to America from Denmark as a teenager. The source of that name has always been a bit of a puzzle, but we've had no way of tracing it further back because the family lost track of its Danish relatives (even their names) years ago. That's always left me a little sad: I've enjoyed connecting with my mother's distant cousins in Sweden, and it would be nice to have something like that on my father's side.

Flash forward to my mother's visit last week. In cleaning out old boxes, she found a letter from one Niels Jensen to his brother in America. The letter talked about all of the surviving siblings back in Denmark (including full names), and a bit of Google searching eventually led me to a definitive match: the family of Rasmus August Jensen (translated here from Danish).

If you look at that list of children, you'll see that there's a distinct lack of Steuards there (by any spelling). But there is a "Søren Ravn Jensen", and a comment in the letter seems to confirm that that was my great-great-grandfather's given name. So apparently I ought to be named Søren! My new theory is that Søren decided at some point that he wanted a more American-sounding name, but when he chose one he wasn't clear on how to spell it. We'll see if this takes us anywhere in the future; it would be fun to see if we could track down any living cousins back in Denmark.

It's been a long, long time since I wrote anything here: I've just finished teaching an intensive one month "Spring Term" class on Medical Physics that met two to three hours a day, five days a week. This might have been less stressful if I'd ever taught (or taken) a class on the subject before (or if I hadn't spent the whole week between my previous final exams and the class starting writing and giving a conference talk in Chicago). But it seems to have gone well, and I've now officially hit summer vacation! That means that I get to procrastinate on baby preparation and paper writing by sharing cool recent science tidbits.

The first is serious physics, and has the potential to be tremendously exciting if it pans out: the CDF experiment at Fermilab may have found the first direct evidence of physics beyond the Standard Model of particle physics! For a nice layman's summary, my friend Sean Carroll has a good writeup at Cosmic Variance; for some more detail, follow the links to posts at Résonaances. I won't try to repeat them here; I'll just show the exciting data:

and comment that the red line is the expected Standard Model result and the blue bump above would presumably correspond to an entirely new neutral particle about 150 times heavier than a proton. This result still isn't 100% solid: it's a "4.8 sigma" result, which is extraordinarily unlikely to happen by chance, but until it's reproduced by Fermilab's D0 experiment or by the LHC there's always the chance that someone forgot to carry a two during the data analysis.

The second thing to share is a beautiful time-lapse video of the Earth rotating under the stars that was recently adapted from an earlier video of stars rotating in the sky. It's a vivid demonstration of the Earth's motion through the heavens that makes you rethink your assumptions about what's really moving when you watch the sky. Here's the video; seriously consider watching it full-screen in HD!

The stairs up to our apartment double as a doorbell: the apartment shakes a little when people come to the door. So when I felt them shaking last night, I thought "Kim's home!" I jumped up to get the door for her, but when I looked outside there was nobody there (false alarms aren't entirely uncommon). I'd obviously been a bit too vigorous as I headed to the door, too: the TV was still rattling a little from where I'd run by. "Boy," I thought, "I really have to be more considerate of the people downstairs: they might have thought there was an earthquake!"

Kim assures me that despite mistaking an actual earthquake for her, I don't deserve to be slapped.