We started to get a naked-eye view of Comet 17P/Holmes last week, after it underwent a transformation in which it apparently ejected a huge cloud of gas, much of which is CN and C2, and NH2 molecules, and which are fluorescing. Unless you knew it, you would think it’s another star in the constellation Perseus, about half way between Cassiopeia and the Pleiades in the northeast sky in the evening. With no moon now and clear skies in Northern California, I got this shot with my little Canon Rebel on a tripod (with a 300 mm Tamron lens, 10 sec exposure at f/4.5):
Looking at it with binoculars, it it hard to resist the urge to try to focus it! But it’s just a big fuzzy ball…
The comet is on its way out of the inner solar system, having made perihelion last spring. The gas cloud has expanded to 70% of the diameter of the sun.
Via Seed, a group of economists chose to study human relationship dynamics under tightly controlled conditions: speed dating. Emphasis added.
With the obvious qualification that we’re talking here about a four-minute version of love and dating, we found that men did put significantly more weight on their assessment of a partner’s beauty, when choosing, than women did. We also found that women got more dates when they won high marks for looks from research assistants, who were hired for the much sought-after position of hanging out in a bar to rate the dater’s level of attractiveness on a scale of one to 10.
By contrast, intelligence ratings were more than twice as important in predicting women’s choices as men’s. It isn’t exactly that smarts were a complete turnoff for men: They preferred women whom they rated as smarter—but only up to a point. In a survey we did before the speed dating began, participants rated their own intelligence levels, and it turns out that men avoided women whom they perceived to be smarter than themselves. The same held true for measures of career ambition—a woman could be ambitious, just not more ambitious than the man considering her for a date.
When women were the ones choosing, the more intelligence and ambition the men had, the better. So, yes, the stereotypes appear to be true: We males are a gender of fragile egos in search of a pretty face and are threatened by brains or success that exceeds our own. Women, on the other hand, care more about how men think and perform, and they don’t mind being outdone on those scores.
Men can be such wimps sometimes.
As mentioned yesterday, I just gave a public lecture about dark energy.
I think the lecture went well. As Jamie said in the comments below, it was literally earthshaking.
Seriously, it seems I have learned out to control the movements of the earth’s crust. I had just finished a rather long leadup about what the universe is made of (from the pre-Socratics through to R&B bands) to introducing dark energy, had just mentioned the 1998 supernovae results on the accelerating universe, and showed my personal favorite graphic about dark energy, which I think I found several years ago in a google search —
and read the label of this lovely substance. Right after the words came out of my mouth, “Dark Energy, it Stinx, but it Rocks!”, the earth started shaking.
Yes, indeed, there was a 5.6 magnitude earthquake, just about 25 miles from where I was speaking, right in the middle of my talk. Right at the punchline. A bit of chaos ensued (doesn’t dark energy always have that effect on people?) but eventually I reigned them all back in with a witty remark and carried on.
Really, I swear I planned that. Can’t wait for the video.
UPDATE: the video is now available! The excitement occurs during minute 34.
“Dark Energy: a discovery so revolutionary, that it shook the earth.”
The crazy kids over at ScienceBlogs have been doing a good deed: running a fundraising campaign for the DonorsChoose charity, an organization that helps out with numerous small-scale projects at public schools across the country. Chad Orzel at Uncertain Principles has been going all-out, drumming up support for a series of worthy proposals. Many of his fundraising pitches involve making fun of atheists such as myself, calling us cheap bastards and referring to St. Richard Dawkins as a doodyhead. But now he needs our help, to spread the word beyond the insular world of ScienceBlogs and ask people in the larger community to help out with the challenge. That’s what we like about Chad: shamelessness!
So let’s prove that we cold-hearted totalizing materialists can also go soft and squishy in the face of needy children, by opening our wallets and donating to a good cause, either to one of Chad’s challenges or to any of the others. Afterwards, you are free to return to your customary relativistic eudaemonic ways, savoring martinis spiced with the chilled blood of baby seals.
And speaking of things to do, Chad also brings up the topic of N things every person/man/woman should know/do/experience. These lists usually serve as cheap ways for writers who have run out of ideas to fill up a few column inches, and typically consist of a dizzy amalgamation of several things that are perfectly trivial, other things that are actually worthy, and many things that make no sense or are strictly impossible. With that paradigm in mind, some time back I whiled away the minutes during an especially boring seminar by constructing my own List of 25 Things Every Person Should Do Once In Their Life. I think it is just as good as anybody else’s list!
How many have you done?
A couple of years ago, I was riding on a train through the German countryside with my family. Out of the fields next to us rose a flock of what must have been several thousand birds, who then executed some of the most beautiful aerial maneuvers I have ever seen, shaping and reshaping a series of organic, flowing patterns against the grey background of clouds. I felt privileged to have been a witness.
So, imagine my delight when the latest issue of Physics Today showed up in my mailbox with the following cover:
There’s a lovely two page article on the STARFLAG project, which is modeling the 3-dimensional flocking behavior of starlings outside of Rome, using 3-d stereograms. The pictures are just spectacular, and give some sense of why I was mesmerized on that German train:
They’re coming up with interesting results about how the birds must be making individual decisions within the flock. They get the best match to the observed behavior by assuming that the birds track their 6-7 nearest neighbors, regardless of local density. (This idea is familiar to astronomers, who frequently use N-th nearest neighbor statistics when estimating density, rather than averaging over a fixed distance.) The distribution of nearest neighbors also seems to be anisotropic, with a tendency to find the nearest neighbors to the sides, where the birds eyes are. Biologists have reached similar conclusions based on models of schooling behavior in fish. However, the STARFLAG project is being led by theoretical physicists at the National Institute for the Physics of Condensed Matter in Italy, so you can imagine that the methodologies are a bit different from what biologists would naturally pursue.
Update: I’m daring to embed a video:
Update on the Update: There’s a longer, informative video here with somewhat better footage. It really picks up in the second half.
Various bits and pieces that have been taking up much needed room in my brain. I now release them onto the internet so I can stop thinking about them.
Religion and Conflict in Battlestar Galactica
Coordinator: Charles Richter
This focus group will explore the many complicated relations between religion and conflict in modern times and throughout history, using the current television program "Battlestar Galactica" as an entry point. The contrasting theologies of the humans and Cylons, their mutually exclusive destinies, and the many moral and ethical issues raised provide us with an accessible point from which to delve into real problems. Some of the topics include: religion in government, suicide terrorism, monotheism vs. polytheism, and bio-ethical dilemmas.
We will view a selected episode every week and discuss the themes presented in accompanying readings. No prior knowledge of "Battlestar Galactica" is required, but we will be watching episodes from various points in the series. If you haven’t seen the show at all, watching the miniseries premiere before the quarter starts would be a good idea in order to get some of the basic premises.
However, I don’t think it would help me to make sense of this.
This may not be the world’s most pressing problem, but it’s one that has started to become more and more odd to me as time has gone by. On the surface, you can easily understand how it has arisen, but the more you consider it the more you wonder just how other people do see the world around them.
We are saturated with video imagery now, in our homes, in shopping malls, airports, and on line. It’s only going to increase with time. So, I ask, why can’t we get the friggin’ aspect ratio correct anyway on all this video?
Up until the last few years, just about all video in the US (and Japan and elsewhere) was displayed in a 4:3 format called NTSC. (Europe adopted different standards, PAL/SECAM, but never mind that for now.) With good old TV, the NTSC format had a resolution of 486 horizontal lines. Translate that into a digital video screen and you’d need 648×486 pixels.
Typical computer screens in the early days had resolutions on that order, but quickly got better. Before long, “XGA” became very common, with 1024×768 pixels. This neatly utilized 10 bits for the horizontal and retained the 4:3 aspect ratio. Cool: all you had to do was translate the video NTSC signal into a digital signal and you could use a digitial monitor!
I’ll skip all the details, but in the past decade we’ve seen an explosion of flat-screen plasma and LCD monitors, which are almost all a wider 16:9 format. This allows them to accomodate the HDTV format, which is designed to have such a ratio, with resolution such as 1920×1080. That’s an aspect ratio of 1.78, quite a bit wider than the old 1.33, but not nearly as big as modern Hollywood films (2.35!).
The problem is that a lot of television (broadcast and cable) is still transmitted in 4:3 ratio, but then displayed on a wide-format 16:9 screen. The designers of the 16:9 monitors have built in the choice (often the default) of simply stretching the 4:3 image to fit the 16:9 screen. The result, as I am sure you have all seen, is that faces and bodies are distorted horizontally by a factor of 4:3 or 1.333. Everyone looks 33% wider, unless of course they are laying down, in which case they look 33% taller. The alternative is to set the monitor to display the 4:3 image so that it uses up all the vertical part of the display but not the horizontal. That seems to bother some people even more than the distorted faces - why buy a big expensive wide screen display and then not use it all?
My own strong preference is to never distort the aspect ratio of image, no matter how big a TV you have. It just looks really stupid to do that. But here we come to the firtst odd thing that I have noticed: some people apparently don’t even notice that there is a distortion! I first encountered this in an electronics store, where the salesperson swore up and down he could see no difference. I’ve asked some random people in various places if they could see the distortion, and around a third claimed not to. You have to wonder how the human visual processing system works…are people who don’t see the distortion internally correcting for this automatically or something?
Even more bizarre is the video you can get online from news outlets like CNN. It’s hard to believe, but they acutally put the distortion into their online video, even though there is absolutely no reason to do so, except perhaps to make it look like it does when distorted on displays you see in public, or in upscale hotel rooms. They are intentionally distorting the image! WTF ? I find this totally baffling.
Here is a random example of some CNN video:
Now if we shrink it horizontally by 25% (3:4 of course!) then it looks like this:
If you cannot see the difference between these, I am baffled. And if you don’t prefer the one where the nice-looking mom’s face is not grossly distorted, then I am even more baffled!
There are perhaps deeper reasons for this effect. Somehow, perhaps CNN thinks that since people have been going around seeing distorted images all over the place, they’ve started to think that this is the new normal? Or perhaps it’s part of the vast media conspiracy aimed at making us feel good about being fat? It’s a fact that more and more obese people are appearing in advertisements…this makes good marketing sense in that people want to identify with the people they see in ads (or at least the advertisers want the target audience to do so) and since such a huge proportion of Americans are obese, adding an additional 33% to their video width is, well, just good marketing.
I would like to believe that this is all a phase, growing pains of our new digital culture. As video designers get better and the hardware gets more sophisticated, I hope that the distorted faces we see all around us will begin to look like the unfortunate by-product of the early phase of this technology. Some day we’ll look back on this and…cringe.
Public transportation in Germany: Efficient, expensive, and deadly
(Spotted on the bergbahn in Heidelberg)
Have you ever heard someone arguing in favor of a position with which you disagree, but their arguments are so bad that you can’t help but think “Man, I could do a better job arguing for their side than they are, and I don’t even agree with them!” I thought it might be interesting to do exactly that — consider some interesting issues, and come up with my own versions of what the people who I think are wrong should be saying.
The rules would be: (1) The claims would be somewhat judgmental, rather than straightforwardly empirical. I’m not going to waste my time arguing that the universe is not expanding, or anything like that. (2) I have to stick to making individual statements that I really do believe, even if I don’t think they are sufficient to support the ultimate conclusion. I reserve the right to come up with more rules as I think of them.
Here are some possible claims to be considered:
Any other suggestions? I’m sure there are lots of things I don’t believe, but could come up with better arguments for than I usually hear. It’ll be like being on the debate team again.