Just about a year ago, a team of scientists reported that Betelgeuse—the bright red star in Orion’s shoulder—appears to have shrunk by about 15% since 1993. That would mean the diameter’s been shrinking at about 1200 miles an hour for all that time.
Such shrinkage—if it’s really happening (it’s hard to be sure)—could be the precursor to a supernova explosion, which would be way cool. The mathematician John Baez computes that a supernova Betelgeuse might be roughly as bright as the full moon, or maybe up to three times as bright.
Surprisingly, it took almost a year for this information to be widely reported on the Internet, but in the past few weeks, a number of sites have cropped up touting the upcoming supernova, and, as you might expect, a few prophecying doom. You can ignore the doomsayers; at a distance of 600 light years, Betelgeuse is too far away to hurt us.
Browsing the various science forums (such as Discover’s), I’m struck by how often the following simple question comes up: Given that Betelgeuse is 600 light years away, is it or is it not true that it would it would take 600 years for us to notice any explosion? Or to put this another way: If the sky lights up with a new moonlike object tomorrow night, does that mean the explosion took place 600 years ago?
A pretty good answer—and the one that’s being given on all those science forums—is “yes”. But that can’t be exactly right, at least not for all of us, because at any given moment some of us are sitting in our living rooms while others are driving on the Interstates. Relativity tells us that if we’re moving relative to each other, then we must disagree about the times of distant events.
Continue reading ‘Beetlejuiced’
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The Diagnostic and Statistical Manual, widely known as the bible of psychiatric medicine, is under revision and the American Psychiatric Association is accepting public comment at a new website.
Medpage Today reports that the revision has already been changed several times in response to these comments. These include several areas within the Sexual and Gender Identities categories, and modifications to the criteria for adjustment disorders and eating disorders.
By contrast, the American Physical Society is not asking the general public to weigh in on the prospects for supersymmetry, nor is the American Economic Association surveying the general public on the properties of dynamic stochastic general equilibria. So much for any pretense that psychiatry is a science.
Hat tip to Tom Amoroso, who called this to my attention though he might not endorse this commentary.
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What are the odds that humankind will survive long enough to colonize the Universe?
Katja Grace argues that the odds are low. Stripped of some nuance, her argument comes down to this:
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The fact that we’re around suggests that intelligent life is likely to be common.
- No other intelligent life appears to have colonized the Universe.
- If they haven’t succeeded, why should we?
By coincidence number one, I discovered Katja’s post (via a ringing endorsement from Robin Hanson) just hours after I’d posted yesterday’s entry here on The Big Questions disputing point 1). Of course, if point 1) fails then so does the entire argument.
Continue reading ‘Our Place in the Universe’
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This diagram, lifted from a lively paper by the astrobiologist Charles Lineweaver, is the tree of life on earth. The “root” at the center is the last common ancestor of all life. Toward the bottom left, you’ll find the genus “Homo”, to which you and I belong, at the end of a twig representing animals. The two neighboring twigs, ending in Zea (i.e. corn) and Coprimus, represent plants and fungi, our two closest relatives.
Professor Lineweaver offers this diagram as an antidote to the superstition that evolution has some tendency to converge on intelligence; his criterion is that we ought not say that evolution “converges” toward some feature unless we observe that feature arising independently in at least two or more twigs. By that same criterion, evolution has no tendency even to converge on heads, which (says Dr. Lineweaver) are likely to be prerequisite for anything like human intelligence.
If human-like intelligence is a fluke, then presumably the ability to build radio telescopes is also a fluke, which stands as a cautionary note for those who expect to communicate with extraterrestrial civilizations.
Continue reading ‘Are We Alone?’
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Some say the world will end in fire; some say in ice. Paleontologist Peter Ward says the seas could turn to sulfur; physicist Michio Kakutani expects the world (along with the rest of the Universe) to end in a deep freeze—though he holds out hope that we could stay warm by escaping to a parallel Universe. Environmental scientist Stewart Brand foresees a climate catastrophe, astronomer Edward Sion worries about supernovas and asteroid impacts, physicst Melissa Franklin contemplates being swallowed quickly and painlessly by a black hole—which wouldn’t be so bad, she says. Astronomer Robert Kirshner imagines a lonely future back here in the Milky Way after the expansion of the Universe transports the other galaxies beyond our observable horizon. Political scientist Graham Allison imagines destruction by nuclear terrorists, and pretty much everyone agrees that sooner or later the earth will be swallowed by a dying sun.
You can watch the video interviews at BigThink, where, as always, I wish they would post transcripts; reading is faster than viewing and skimming is faster still. But if you’ve got the patience, some of these are fun.
What’s your (realistic or fanciful) scenario for the end of days?
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I love evolutionary biology, so I love this argument: Beauty is more valuable to girls than it is to boys, so beautiful parents should have more daughters than sons. You want (or at least your genes want) to pass on your assets to children who can make the best use of them.
So I was delighted by recent news reports that beautiful women do indeed have more daughters. But I was stunned by the reported magnitude of the effect: According to one report, beautiful people are 36 percent more likely to have a daughter than a son!
Continue reading ‘Beauty’s Daughter’
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Between The Folds is a striking documentary about the art and science of origami. I’ve watched an advance copy, provided by the producers, and it’s really quite mesmerizing. Roughly half the program is devoted to artists like Satoshi Kamiya, who folded this extraordinary dragon, according to the rules of origami, from a single piece of paper with no cuts. In the second half, we meet mathematicians and scientists like Robert Lang,
pictured here in front of the folding lens he designed for the Hubbell Space Telescope—folded, it fits inside a small rocket ship for delivery to its destination in space, where it unfolds automatically—and Erik Demaine, the paperfolding enthusiast and Macarthur “genius” award winner who is applying origami to the design of synthetic proteins that fold reliably into the proper configurations.
“Between the Folds” has its national television debut tomorrow night (Tuesday, December 8 on PBS; check your local listings for the time). Or check here for additional showings.
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