Can we build a more efficient airplane? Not really, says physics.
As a plane hurtles through the air, it carves out a tube of air, much of which is deflected downwards by the wings. Throw down enough air fast enough, and you can stay afloat, just as the downwards thrust of a rocket pushes it up. The key is that you have to throw down a lot of air (like a glider or an albatross), or throw it down really fast (like a helicopter or a hummingbird).
A look at the cavity quantum electrodynamics work that Serge Haroche pioneered. Dave Winelend, the other physics Nobel winner, does investigations using ion traps.
There’s a number of short videos with Wineland done by the Institute for Quantum Computing — From Atomic Clocks to Ion Traps: David Wineland at IQC
And Chad has a summary up at Uncertain Principles: What’s So Interesting About Single Quantum Systems? Physics Nobel 2012
Prolific week for Chad Orzel, with the Nobel summaries and this piece on spectroscopy:
Gandalf Was Wrong: Middle-earth Needs Science
[A]s I grew up to become a physicist working with atoms and lasers, I’ve only become more convinced that Gandalf is wrong. Splitting light isn’t a mistake, it’s the first step on the path toward our modern understanding of the universe.
Hey, Physics & Astronomy Professors? THIS IS NOT OKAY!
I recognized long ago that it’s important to have a full life that includes a lot more than just my scientific interests for my physical and mental health and well-being. Which is why I’m absolutely livid over this letter, circulated in a top astronomy department (which — I cannot prove — but I believe I once worked at), reproduced in its entirety, with my commentary, below.
I routinely worked >60-hour weeks in grad school, or at least I was at school for at least 60 hours a week — there was always some late-night decompression (hall golf or some game on the computer). In at 11 and leave for home after midnight was routine for the lab, with breaks for meals, and then additional time the weekends. (I did a few 80+ hour stints as a postdoc at TRIUMF, because when you have beam time, you run the experiment 24/7.) I also got the “this isn’t a 40-hour a week job” lecture once, during a rough patch when I was “only” putting in about that amount. But I also got time to myself to have a little bit of a life — limited to what you might have on a grad student stipend. This letter is over the line, unless the purpose is to drive people entirely from the field.
Jurassic Park Impossible Because of Stupid Laws of Physics
It might be odd to think of DNA having a half-life, as it’s usually associated with radioactive material — but as it measures the time taken for half of something to decay, it makes sense to talk about old samples of DNA in the same way. For example, uranium-235, the fissile material that can be used in nuclear power plants (and nuclear weapons), has a half-life of 703.8 million years. DNA, by comparison, doesn’t fare so well — according to a study of 158 samples of moa bones between 500 and 6,000 years old, DNA appears to have a half-life of around 521 years.
Actually, anything driven by a simple probability is going to behave this way, where the rate of loss depends on how much you have. There are biological half-lives for some substances you ingest, which tells you how long it will take to metabolize or excrete that substance.
Physics Nobel goes to Serge Haroche and David Wineland
The Nobel citation said the award was for “ground-breaking experimental methods that enable measuring and manipulation of individual quantum systems”.
Always extra nice (for me) when it’s familiar faces from AMO physics. There’s a good summary up at Uncertain Principles
New Extreme Sport Combines a Jet Pack with a Jet Ski
No, I didn’t lose balance. I was diving.
Entangled in the Past: “Entanglement Between Photons that have Never Coexisted”
[T]wo entangled pairs of photons are created, and then a joint measurement of one photon from each pair creates an entanglement between the other two. The twist this time is that one of the photons from the first pair has already been measured before the second pair is even created.
1,001 Mind-Blowing Facts About Yo Momma
Style aside, there’s another reason I’m not a big fan of omnibus fact lists: that’s not a very scientific way to organize knowledge. Facts are some of the least useful things in science, so just dumping a list of them on readers will not generally result in much gain in understanding.
I agree with Matthew. I think most science facts should more accurately be termed science trivia. And there are a lot of science literacy quizzes which only test trivia. (Though there are some which do reward literacy if you haven’t memorized the answer but can still figure it out.)