Blogs / Cosmic Variance

Physics is lovely. Cosmology is profound. Astronomy is a thrill. That’s all well and good, but for those of you who are thinking of pursuing it as a vocation, what you may really want to know is, “What’s in it for me?”.

The answer? Lots and lots of cash.

Courtesy of the always fascinating American Institute of Physics Statistical Research Center’s latest report, if you major in physics and land a job in a technical (”STEM”=”Science, Technology, Engineering, and Math”) field, you’ll make nearly twice as much as you would have in a non-technical pursuit. Short term you’ll be screwed financially if you go on to grad school (see the “University” entry), but if you hold on for a higher degree, you’ll do even better:

Well that’s interesting, but what’s my point? Namely, that whatever your beliefs about why white straight men are overrepresented in science and engineering, you’d be hard pressed to deny the financial impact. When women and minorities are underrepresented in scientific and technical majors, they are necessarily overrepresented in the “Bachelor’s non-STEM” box in the upper left of the plot above. If more of them drop out while pursuing advanced degrees, they’ll never make it to the high Ph.D. salaries in the lower right. These differences can accumulate into more than a million dollars over a 20 year career, and make tangible differences in people’s quality of housing, childcare, and health insurance.

So, while the social costs matter, it’s the economic costs that worry me most.

Jonathan Dorfan, the director of the Stanford Linear Accelerator Center (SLAC), made a stunning announcement this morning - he is stepping down from the laboratory directorship this Fall. This news is certainly a surprise - at least to me! It seems that this decision is all about timing. This Fall marks Jonathan’s 8^th year as laboratory director, as his tenure began in the Fall of 1999. Factor in that Jonathan has said he believes change at the top is healthy for large organizations and when he accepted the directorship he stated his intent to serve only for 8 to 10 years. Couple this to the fact that SLAC’s contract with the Department of Energy will be sent out for bids and competed against in about two years time. And recall that when a new contract is drawn for the lab in this two years time, one condition of the contract is that the lab’s directorship must pledge service (i.e., stay in place) for an additional five years. Jonathan apparently looked at the numbers and decided that now is the right time to step down.

Stanford University President John Hennessy said, “Jonathan Dorfan’s tenure at SLAC has been characterized by exceptional scientific vision and foresight. He deserves our thanks—and those of the greater scientific community.”

During Jonathan’s tenure, he has accomplished many things, including:

The Stanford President has asked Persis Drell, deputy director of SLAC, to head the search committee for Jonathan’s replacement. The committee will be established shortly, will conduct a world-wide search and report back to the President. Jonathan will remain on the SLAC faculty and will no doubt become actively involved in actually doing science again.

Best wishes to Jonathan, and thanks for what you’ve done!

It was new at the time, anyway. The model being spoken of is the Big Bang, first suggested by Father Georges-Henri Lemaitre in 1927. (The expanding-universe solutions to general relativity had also been derived by Alexander Friedmann in 1922, but he hadn’t emphasized the nature of the intial singularity in such models.) Lemaitre, a Belgian priest who studied at Harvard and MIT, proposed what he called the “Primeval Atom” or “Cosmic Egg” model of the universe, and derived Hubble’s law, two years before Hubble and Humason actually discovered that the universe is expanding. Einstein wasn’t all that fond of Lemaitre’s idea — having been assured by his astronomer friends that the universe was static — but he encouraged Lemaitre in his investigations.

All of which springs to mind because the Modern Mechanix blog has unearthed a Popular Science article from 1932 by Donald Menzel, an astronomer at Harvard, that explains Lemaitre’s ideas. (The time between Hubble and Humason’s discovery and Menzel’s article is somewhat less than the time between the 1998 discovery of dark energy and Richard Panek’s New York Times Magazine article from yesterday.) Menzel’s piece does a great job of explaining the basics of the Big Bang model, long before it was given that name by Fred Hoyle. Indeed, he touches on many of the questions that still arise in a good Cosmology FAQ! For example, he emphasizes that the redshift is due to the expansion of space, not to the Doppler effect.

The case of the universe is analogous, except that the expansion, being of a three-dimensional volume, cannot be visualized. The phenomena are, however, comparable. The nebulae are not running away from us. Their recession is due to expansion of space. This may, perhaps, seem to be quibbling over terms, since it amounts to the same thing in the end. Nevertheless, the distinction is worth keeping. According to the relativity theory, there is a difference between the running away of the nebulae and expansion of the medium in which they are imbedded.

Sadly, he also appeals to the much-hated balloon analogy for the expansion of the universe, although he uses the surface of the Earth rather than the surface of a balloon; in fact, it’s a better choice. And he’s not afraid of diving into the sticky questions, like “What happened before the Bang?”

DR. LEMAITRE’S hypothesis does away with the old query as to the state of affairs before the beginning of things. Going back to the parent atom we may inquire about what happened before the cosmic explosion took place. The answer is: — Nothing. – Computation shows that space would have closed up around the massive atom and, certainly, nothing can happen where there is no room for it to happen. Time has no meaning in a perfectly static world. The age of the universe is to be reckoned from that prehistoric Fourth of July, when space came into existence. Since then, space has been continually expanding before the onrushing stars, sweeping the way for them, forming a sort of motorcycle squadron to make room for the star-procession to follow.

Like many contemporary cosmologists, Menzel is a little more definitive about this than he really should be. When asked “What happened before the Bang?”, the correct answer is really “We don’t know. According to general relativity, space and time do not exist before the Bang, so there is no such thing as ‘before.’ However, we have no right to think that general relativity is correct in that regime, so… we don’t know.” Few people are sufficiently straightforwardly honest to give that answer.

And what about the future?

SO MUCH for the present. What of the future? Einstein and the noted Dutch astronomer, Willem de Sitter, have talked of some future contraction, which might sweep up the stars along with cosmic dust and eventually bring the world back to its original state. Dr. Lemaitre thinks that such a contraction cannot occur. He prefers to believe that the whole universe was born in the flash of a cosmic sky-rocket and that it will keep expanding until the showering sparks which form the stars have burned to cinders and ashes.

We still don’t know the answer to this one, but the smart money is on Lemaitre (and against Einstein, who liked his dice unloaded and his universes compact). Now that we know the universe is not only expanding but accelerating, the simplest hypothesis is that it will keep doing so. To be honest, of course — we don’t know!

Lemaitre passed away in 1966, a year after Penzias and Wilson detected the microwave radiation leftover from the Primeval Atom.

I guess I never would have expected that the story of our little bump in the mass spectrum in our search for the Higgs could have taken on such a life of its own. After my initial presentation in Aspen in January, within our tightly-knit field of experimental particle physics there was certainly a wave of interest, which crested and then subsided in February. But by then, after my accounts here in CV, the mainstream media wheels began to turn and we have had coverage last week in New Scientist and now a sort of unattributed blurb in this week’s Economist.

This past week I spoke on the phone with Dennis Overbye from the New York Times, who is headed to CERN next week. He is a very sharp guy, and zeroed right in on the issues, both with this story and that of the impending startup of the LHC at CERN and the longer term future in this country, including the possibility of hosting the ILC here some day.

And I got a call from the Neue Zurcher Zeitung yesterday, though only had a short time to talk. His thrust seemed to be along the lines of challenging the idea that physicists should be carrying on scientific discourse in the blogosphere. My own attitude is sure, why not? Our obligation within our large collaborations to our colleagues is to honor the bylaws for the publication of our results, which undergo a stringent review process, but then when “blessed” I think we all feel free to show and dicuss the results, with the caveat that they are “preliminary” and may change before appearing finally in a peer-reviewed publication. I think it is wonderful to have another forum for this discourse and it’s even better that the public (who foot the bill for all this) get to see some of it happening, and even participate. Scientists, especially in our field of particle physics, need to communicate to the public just how fundamental the questions we address are, and how close we are to breaking open the next layer of the structure of matter, energy, space, and time.

But I fear that the mainstream media coverage of this has gone off the rails. We as high energy physicists are certainly excited about making, at long last, an observation of the Higgs, and perhaps starting to get a glimpse of dark matter particles produced in our collisions. These are the great pressing questsions of our day in our field. The answers could emerge within the next few years, and whatever it is we uncover will be, I bet, a great surprise to us all. We’re keeping our eyes open and looking in lots of places. And we’ll probably get a lot more “false positives” along the tortuous path to full understanding. That’s how science works. I do hope the media don’t seize upon every little bump in the road (so to speak) or there could ensue some fatigue with the topic.

But here is the bottom line, in my view:

• What we have in our hands now, this little 2-sigma excess in the tau pair mass spectrum, is just that.
• These things happen all the time, and oftentimes evaporate just as fast as they appear.
• We need more data, we have it, and we shall soon have it analyzed.
• CDF sees an excess in tau pairs, and the D0 experiment does not - they see a deficit where we have our excess!
• CDF has seen a beautiful (no pun intended) signal for Z -> bb, and in that mass spectrum they could in principle see the Higgs but in
  my opinion it seems like they aren’t quite as sensitive as the tau pair analysis, and would not have been expected to see anything yet.

• D0 has an interesting wiggle in their lower-statistics analysis of Z -> bb and it would be fascinating to see their latest data.
• If we don’t see it soon the LHC will in the next couple of years.

We’ve been waiting a long time for the Higgs…stay tuned…

PZ Myers — looming, hulking titan of the science blogosphere — turns an even half-century old tomorrow. Bloggers of all stripes are coming out to celebrate, with links being collected by John McKay, GrrlScientist, and Coturnix. (I’m not sure what’s the big deal about 50. The number only looks special because it’s the number of fingers on one hand times the number of fingers on both hands. A less parochially antropocentric anniversary would be 64, which is the square of the number of arms on a cephalopod. But I’m not in charge.)

I would like to give PZ a nice birthday present, as he played an important role in my life as a blogger: he gave me my first link ever. I could write him a poem, like Richard Dawkins did, but trust me you don’t want that.

So I had the great idea of sharing my favorite cephalopod-related video — this clip of a guy eating live octopus tentacles.

But then I thought about where I had actually seen this first — and, yes, it was on Pharyngula. Damn you, PZ! Still, if you’re in the LA area and are jonesing for some live tentacles, we’ll hook you up.

So finally I decided to give PZ something he’d really appreciate — his astrological chart.

The “interpretation” goes on and on about the implications that Pluto is in 28 degrees Leo, etc. (I guess they still think it’s a planet.) But here’s the punchline:

Rising Sign is in 03 Degrees Aries

You are a free spirit and you must be first at everything you do. Very energetic, self-assertive and active, things must be done your way. Even though you may feel calm and serene on the inside, you certainly do not act that way. You want to do everything full-tilt, 100 miles per hour! A great competitor, but a poor cooperator — you must learn how to lose more gracefully. Very self-confident, ambitious and passionate, you radiate positive energy. You are blunt and direct, but at times unfeeling and tactless, especially if anyone offers you any resistance. You fight for your beliefs, but your tendency to act first and think later often causes you much grief.

Man, I don’t know. Seems pretty darn accurate to me. I might become a believer, despite my principled misgivings.

Happy Birthday, PZ!

In a remarkable display of scientific federalism, a member of New Mexico’s state legislature introduced legislation that when Pluto is in New Mexico’s airspace, it’s a planet:

NOW, THEREFORE, BE IT RESOLVED BY THE LEGISLATURE OF THE STATE OF NEW MEXICO that, as Pluto passes overhead through New Mexico’s excellent night skies, it be declared a planet and that March 13, 2007 be declared “Pluto Planet Day” at the legislature.

I just do not get this. We gave up the brontosaurus without a whimper. A whole dinosaur just disappeared without protests or heartfelt letters to the Museum of Natural History — and not a minor dinosaur either — one of the big ones that even those who don’t have kids knew about. But people just can’t let Pluto go. Just check out the t-shirts alone! (My favorite is the one that says “Pluto. Never Forget.”, but has a picture of Jupiter. I guess they forgot.)

Really, the situations are analogous. The brontosaurus was misclassified because the first prototypical skeleton was missing a head, so they guessed and put the wrong one on. Eventually they figured it out and lumped the brontosaurus back in with apatosaurus where it was supposed to have been all along. Likewise, Pluto was misclassified because we didn’t know enough about the outer reaches of the solar system to recognize that it had much more in common with a different class of objects than the inner planets. Same deal. But poor old brontosaurus never got the press, while Pluto has the New Mexico legislature weighing in. Baffling.

Readers who hang out in the Southwestern quadrant of the U.S. should be aware of the lecture series at Caltech sponsored by the Skeptic’s Society. Past speakers include such luminaries as Richard Dawkins and Lisa Randall; future highlights include a debate between Frank Tipler and Lawrence Krauss on “Can Physics Prove God and Christianity?” That should be, how shall we say, somewhat surreal.

This Sunday at 2:00 there is a lecture on The Physics of Pouty Teenagers Fighting Vampires, or something like that. Apparently there is even a book along those lines. I’m too high-minded to think about such things myself, but I’ll probably go to this lecture, because the speaker looks like a total babe.

Chad at Uncertain Principles raises the issue of unfortunate names in physics and astronomy. I agree that “strange” and “charm” and “bra” and “ket” are on the cutesy side, but astronomical nomenclature has got to be worse. A fair bit of it is just awkward (for example, in a young star formation region, you’ll often find both molecular hydrogen, which is H₂, and ionized hydrogen which is also known as “H-two”, i.e. “HII”, where the II is the roman numeral two). Other terms are historical anachronisms (”planetary nebulae” have nothing to do with planets, but they looked sort of like them through the earliest telescopes). However, to the astronomer teaching large introductory courses (which is most of us), astronomical lingo is downright perilous.

Case in point: The spheroidal distribution of stars in the centers of rotating disk galaxies is called the “bulge”. Now, introduce a bunch of bored and horny 19 year olds into the mix, and you have a dangerous cocktail. One of my colleagues lost complete control of a 250 person lecture class when she had two male students hold up pictures of different galaxies, while she expounded on how “This guy over here has a small bulge, but the bulge of this guy is quite prominent.” The titters started as she forged ahead unknowing, until the entire class collapsed in hysterics. At that point, you just have to put down your laser pointer, send the class home, and head for the bar. Learning is over.

While not quite as extreme, I’ve always been fond of “violent relaxation“, originally coined by Donald Lynden-Bell . The relaxation bit refers to a gravitationally bound system (like a galaxy) coming to its final equilibrium state, and the violent part refers to the fact that this process is not slow and steady, but is usually characterized by rapid changes in the gravitational potential. Broken down like that, it’s not as nuts as you’d initially think, but it’s never going to sound PG.

The BBC has a fun little story about South Korea’s soon to be released ethical guidelines for dealing with robots, anticipating truly intelligent robots in the not too distant future. The story contains some discussion of whether these guidelines should resemble Asimov’s famous three laws of robotics:

1. A robot may not injure a human being or, through inaction, allow a human being to come to harm.
2. A robot must obey orders given it by human beings except where such orders would conflict with the First Law.
3. A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.

But what I found strangest about the story is the following:

The new charter is an attempt to set ground rules for this future.

“Imagine if some people treat androids as if the machines were their wives,” Park Hye-Young of the ministry’s robot team told the AFP news agency.

I’m really not sure how to read this. I guess it could be a point about the obvious possibility of human-robot sex, but I think it more likely that it is meant to say that you can’t just go around treating a robot as badly as you might treat your wife!

A whole life of making minimal demands, of keeping to myself, of doing all my chores promptly and well, of getting superlative grades, of being a star in band, of being a dutiful student of the piano, of having good and well-behaved friends, of working ever since I was old enough to drive — that all meant nothing. Being good hadn’t preserved me from random interrogations, in fact made me more vulnerable — I bought into their standard of judgment and tried to defend myself according to it, once even breaking down in tears, a seventeen-year-old kid, breaking down into incoherence, collapsing into a fetal position, and she just walked away. Even now, if something ever comes up in conversation, she acts like she doesn’t remember, like it was someone else entirely — she apologizes on behalf of this other person, over-eagerly, like she’s apologizing for some weird misunderstanding that she can’t fully assimilate.

Dave Brubeck and Heidegger. Adam Kotsko tells a short cliched-sounding tale — growing up with parents who don’t understand you — that he elevates into a moving memoir. I’m glad to have been quite a bit more fortunate.