drorzel | August 16, 2010Last week's series of posts on the hardware needed for laser cooling and trapping experiments dealt specifically with laser-cooling type experiments. It's possible, though, to make cold atoms without using laser cooling, using a number of techniques I described in two posts back in January. Those didn't go into the hardware required, though, so what's different about those techniques in terms of the gear?
Less than you might think. In fact, most of the labs that do these experiments use exactly the same sorts of equipment that laser coolers do. Including some lasers.
It's not all of them, but…
drorzel | August 16, 2010
Sex between adolescents in romantic relationships is often harmless to their academics
"The context in which adolescent sexual activity occurs can substantially moderate the negative relationship between sexual intercourse and education, according to research to be presented at the 105th Annual Meeting of the American Sociological Association.
"Compared to abstinence, sexual intercourse in committed romantic relationships is often academically harmless, whereas in other types of relationships it is more detrimental," said Bill McCarthy and Eric Grodsky, sociologists at the University of…
drorzel | August 15, 2010A slightly different twist on the occasional guess-the-lyrics game. The following list gives pairs of rhyming words from a song that I think can be used to identify a specific song. So, for example, the pair:
diplomat/ Siamese cat
identifies "Like a Rolling Stone" by Bob Dylan, thanks to the lines:
You used to ride on a chrome horse with your diplomat
Who carried on his shoulder a Siamese cat
Your mission, should you choose to accept it, is to guess the songs from the rhymes below. Some are pretty easy, some are pretty obscure. If you don't choose to accept this mission, well, come back…
drorzel | August 15, 2010A couple of new-to-me but good physics blogs to point out this week:
All That Matters by Joerg Heber. This looks like it will be updated weekly-ish, and has a couple of good entries, including a nice write-up of an ultrafast laser experiment that I had flagged to write about before I got distracted by crazy people and lab porn this week.
The Dayside by charles Day of Physics Today. This has roughly daily updates, on a wide range of stuff.
Both of these cover physics beyond the default particle-physics-and-cosmology that you can find in dozens of places, and Day even has a post titled Why I…
drorzel | August 15, 2010
YouTube - Beat It + epic Crazy Chinese Omnipotent China red army
The Internet is a very silly place, but I'm glad we have it.
(tags: video music world silly internet youtube)
Why Does College Cost So Much? - Forbes.com
"Instead of holding up a magnifying glass to the industry, we take an aerial view. The view from above shows us different things. Rising college costs are an important byproduct of broad economic forces that have reshaped the entire economy, and in particular of the technological progress that has so dramatically raised living standards over time.
Our technology story rests…
drorzel | August 14, 2010Tongues of Serpents is the nth book in the Temeraire series started with His Majesty's Dragon (in the US, anyway), and another "Meh" review from me. In this case, this is probably less to do with the book itself than with the fact that I am not really in the target demographic for this book.
The series, for those who aren't familiar with it is basically Patrick O'Brian crossed with Pern: our chief protagonist is William Laurence, a sailor in the Biritsh Navy in the Napoleonic Wars who captures a dragon's egg, and inadvertently becomes the human captain of Temeraire, a Chinese Celestial dragon…
drorzel | August 14, 2010I don't believe the actual book is out yet, but you can get an electronic Advance Reading copy of the Nth Miles Vorkosigan book, Cryoburn already. Kate picked up a copy, and while she hasn't gotten around to it yet, I read it this week while putting SteelyKid to bed.
The book is another "Lord Auditor Vorkosigan" story, with Miles on a mission to Kibou-Dani, a half-terraformed planet with a positive fetish for cryopreservation. A quirk in local laws gives the "cryocorps" that preserve millions of frozen citizens the right to proxy vote for their clients, and control of their property, so they…
drorzel | August 14, 2010
Shtetl-Optimized » Blog Archive » Eight Signs A Claimed Pâ NP Proof Is Wrong
"So, in the future, how can you decide whether a claimed Pâ NP proof is worth reading? I'll now let you in on my magic secrets (which turn out not to be magic or secret at all).
The thing not to do is to worry about the author's credentials or background. I say that not only for ethical reasons, but because there are too many cases in the history of mathematics where doing so led to catastrophic mistakes. Fortunately, there's something else you can do that's almost as lazy: scan the manuscript, keeping a…
drorzel | August 13, 2010Over at the Whatever, one of Scalzi's guest bloggers has posted a ginormous list of upcoming live music shows in the DC area. This makes me sad, because when I used to live in the DC area, I was a grad student, and couldn't afford to go to any of the dozens of great concerts that came through there. Now that I have plenty of money I could spend on live music, I live in Schenectady, where we don't get anywhere near as many good shows, and I have a wife and child to boot, which makes it difficult to justify going out.
Anyway, whining aside, this seems like a good topic for a reader poll: What…
drorzel | August 13, 2010The third category in our look at lab apparatus, after vacuum hardware and lasers and optics is the huge collection of electronic gear that we use to control the experiments. I'll borrow the sales term "test and measurement" as a catch-all description, though this is really broader than what you'll usually find in that category.
This category covers all sorts of stuff, from power supplies to data acquisition equipment, but we'll start with the oscilloscopes.
The picture above shows two of the many oscilloscopes that rattle around my lab. These are used for almost everything that involves a…
drorzel | August 13, 2010Some folks I used to work with at NIST have looked at cheap green laser pointers, and found a potential danger. Some of the dimmer-looking green lasers are not so dim in the infrared, and in one case emitted 10X the rated power in invisible light. This could be a potential eye hazard.
You can read their full report on the arxiv. It's got a nice description of how green laser pointers turn infrared light into visible light, which is really pretty awesome-- a guy I met at a conference once declared them the coolest invention ever, because it's "quantum optics in the palm of your hand." Better…
drorzel | August 13, 2010
Think Globally, Compromise Locally - Green Blog - NYTimes.com
"Bill McKibben, whose 1989 book, "The End of Nature," helped coalesce and spread worry about climate change, views the national environmental groups' strategy of winning support for energy and climate legislation by compromising with industry as a complete failure. "The result: total defeat, no moral victories," he wrote at the environmental news site Grist, speaking of the Senate's inaction on climate legislation.
"Making nice doesn't work," he added.
Whatever the merits of his position, it has less traction when it comes to…
drorzel | August 12, 2010Now that she's officially two years old, SteelyKid gets to sit in the big chairs:
She also insisted on the forced-perspective thing to make her look even bigger compared to Appa. And the string cheese. She's all about the string cheese.
drorzel | August 12, 2010My parents are in the Caribbean at the moment, and threatened to send me cell-phone pictures of white beaches and blue water. They were thwarted in this by the fact that I still have a cheap LG flip phone with no camera. Our calls from home are exclusively made using a landline phone.
You can see the reason why in the picture at right. This was taken in our living room the other night, and as you can see, we get barely one bar worth of signal in the house. This is fairly typical-- there are a few spots in the house where it rises to two bars, but an intermittent "no signal" is fairly common.…
drorzel | August 12, 2010The problem with writing about fake physics is that once you start, it's hard to stop. And there's always something new and disreputable to find, such as this hideous bit of scammery. As I said in How to Teach Physics to Your Dog, if quantum physics really allowed you to amass vast wealth just by wanting it, Dave Wineland's publications wouldn't need to acknowledge funding from a handful of acronyms-- he'd be able to bankroll his own research out of his personal fortune..
Quantum physics is not magic. It allows many things that seem weird and counterintuitive, but those effects are very…
drorzel | August 12, 2010Following on yesterday's discussion of the vacuum hardware needed for cooling atoms, let's talk about the other main component of the apparatus: the optical system. The primary technique used for making cold atoms is laser cooling, and I'm sure it will come as no surprise that this requires lasers, and where there are lasers, there must also be optics.
There are lots of different types of lasers used for laser cooling experiments, but they all need to have certain properties: tunability, stability, and adequate power. Tunability is important because laser cooling requires light at exactly…
drorzel | August 12, 2010
If Physical Books Are Dead in Five Years, How Do the Poor Find Books? Whither (or Wither?) the Library? : Mike the Mad Biologist
"The great promise of our libraries is that, if you can physically get there (and for some services, even that isn't required), you have access to the materials, rich or poor. And in the 21st century, that also means the internet, for those who can't afford to access it. Personally, I use the library all the time, and it seems a pretty bustling place to me--if anything, it would appear library use is soaring, at least in Boston.
Books need to be accessible to all…
drorzel | August 11, 2010Over in the reader request thread, Richard asks for experimental details:
I'd be interested in (probably a series) of posts on how people practically actually do cold atoms experiments because I don't really know.
I needed to take some new publicity photos of the lab anyway, so this is a good excuse to bust out some image-heavy posts-- lab porn, if you will. There are a lot of different components that go into making a cold-atom experiment, so we'll break this down by subsystems, starting with the most photogenic of them, the vacuum system:
(Click on that for a much bigger version.)
This…
drorzel | August 11, 2010First Matt Yglesias and then Kevin Drum nail the current source of my occasional spasms of liberal guilt, namely the unequal distribution of the current economic troubles. They both note that the unemployment rate for college graduates is less than half that for folks without college degrees (Matt looks at total unemployment, Kevin at long-term unemployment), and Matt notes:
Virtually every single member of congress, every senator, every Capitol Hill staffer, every White House advisor, every Fed governor, and every major political reporter is a college graduate. What's more, we have a large…
drorzel | August 11, 2010A Japanese physicist who I worked with as a post-doc spotted the Japanese edition of How to Teach Physics to Your Dog in the wild, and picked up a copy. He sent along a scan of a couple of pages of the text, one of which I reproduce here:
I had totally forgotten that Japanese books are often printed with the text in vertical columns from right to left, which creates a slightly weird effect. What's even stranger, though, is the way the equations are done-- they're also rotated to be vertical, but the kanji characters are rotated as well. Not that the rotation changes the readability in any…