Physics
rallain | May 3, 2010This video seems like it is getting popular, but maybe that is because it is so awesome.
Maybe it is just me, but I find this video very visually satisfying. I love the way they compare the different runners.
Anyway, there is some physics here. Commenter Ben sent me the link to this video (thanks!) with some great questions. Which of the runners has a greater kinetic energy? What about the power? These aren't too difficult to answer, but the first thing is to get the data. There are several options (including just using a stop watch). But no, that is not good enough for me. Instead, I…
drorzel | May 3, 2010While I missed the controversial episode with comments about aliens, I figured I should at least take a look at the Discovery Channel's Into the Universe with Stephen Hawking, so I put it on last night after putting SteelyKid to bed. This was the big two-hour "Story of Everything" episode, starting with the Big Bang and describing the whole history of the universe.
I made it through about half an hour, before I gave up and went to bed. This was partly due to it being a really long day (I took SteelyKid shopping and to a playground, did some yard work, and went to a meeting on campus), so I…
drorzel | May 3, 2010Voting has closed on the Laser Smackdown poll, with 772 people recording their opinion on the most amazing of the many things that have been done with lasers in the fifty years since the invention of the first working laser (see the Laserfest web site for more on the history and applications of lasers). The candidates in the traditional suspense-building reverse order:
Lunar laser ranging 22 votes
Cat toy/ dog toy/ laser light show 41 votes
Laser guide stars/ adaptive optics 46 votes
Holography 47 votes
Laser eye surgery 53 votes
Optical storage media (CD/DVD/Blu-Ray) 60 votes
Laser…
drorzel | May 2, 2010With over 700 votes cast in the Laser Smackdown poll in honor of the 50th anniversary of the laser, laser cooling has opened a commanding 20-vote lead in the race to be the Most Amazing Laser Application of All Time. If you prefer one of the other options, you have only six hours left to change the final outcome:
Which of the following is the most amazing application of a laser?Market Research
Voting will remain open until midnight, with the ultimate winner announced on Monday, May 3rd. So get reading, and get voting. One vote per computer per user, please-- this is Serious Science.
esiegel | May 2, 2010Either write something worth reading or do something worth writing. -Benjamin Franklin
Every weekend, I try to bring something light to you, but there's a lot of heavy stuff going on in the world right now. So instead of the usual, I'd like to tell you just a little bit about why putting even a little bit of oil in the oceans can be so disastrous.
And I can't think of a better modern voice to take us through that than Regina Spektor, whose voice reminds me of greats such as Nina Simone and Ella Fitzgerald. Take a listen to her song Apres Moi.
Apres Moi by Regina Spektor
Most of you know that…
drorzel | May 1, 2010The APS now gives out an Abraham Pais Prize for History of Physics, which gives you some idea of how influential his work was, in particular "Subtle Is the Lord..." The Science and Life of Albert Einstein, which won prizes and sits in a prominent position on the bookshelves of many physicists. Like a lot of influential works, though, it's kind of odd to read it much later than some of the works it has influenced.
The ordering of the subtitle is very deliberate, and accurate. This is first and foremost a book about Einstein's science, with a biographical structure and occasional biographical…
drorzel | May 1, 2010A college classmate sent me this picture of a library display in the Boston area:
That's How to Teach Physics to Your Dog prominently displayed on the top shelf. Just below it, you can see Physics for Future Presidents, and to the right, you can just make out Richard Dawkins's book on evolution. Pretty good company to be in, and even better to be on top of...
(Yes, I know, relative position in a library book display doesn't have anything to do with anything. It's fun to pretend, though...)
(Thanks for the picture, Andrew.)
drorzel | April 30, 2010I'm off to Williamstown this afternoon, to talk about research and alsoHow to Teach Physics to Your Dog. If you need blog-based entertainment, though, here are some shiny new radio buttons for you to click:
You're a beam of light: quick, what's your polarization?online survey
I won't offer a personality analysis based on these results, but after enough people vote, we will be able to determine the angle between this blog's readers and the horizontal. So that's something. Of course, it would require several more polls for full quantum state tomography...
(If you're new here, or ok with old…
drorzel | April 30, 2010We're just over 600 votes in the Laser Smackdown poll in honor of the 50th anniversary of the laser, as of early Friday morning. I notice that it has moved off the front page of the blog, though, so here's another signal-boosting repost, just so we have as many votes as possible, to establish maximum scientific validity when we declare the winner the Most Amazing Laser Application of All Time
Which of the following is the most amazing application of a laser?Market Research
Voting will remain open until next Sunday, May 2, just two days from now, with the ultimate winner announced on Monday…
drorzel | April 29, 2010Over in Twitter-land, S. C. Kavassalis notes a Googler who's not afraid to ask the big questions:
Weird Google search of the week: 'the "one" scientific idea that we need to believe'. Uh um, I'm sure my blog couldn't possibly answer that.
It's a good question, though, ad there are a couple of different ways to take it. You could read it as "What one scientific idea is supported by the most experimental proof?" or you could read it as "What one idea is most central to science generally?"
"The Standard Model" was quickly suggested on Twitter, which could fit either. I think it might be…
drorzel | April 29, 2010A sad and sordid story from the Times Higher Education following the rescinding of invitations to a conference on quantum foundations:
Details of the conference in August for experts in quantum mechanics sounded idyllic. Participants were due to discuss "de Broglie-Bohm theory and beyond" in the Towler Institute, which is housed in a 16th-century monastery in the Tuscan Alps owned by Mike Towler, Royal Society research fellow at Cambridge University's Cavendish Laboratory.
Last week, any veneer of serenity was shattered. Conference organiser Antony Valentini, research associate in the…
rallain | April 28, 2010Normally, it isn't really news when a show doesn't do anything wrong. I am making an exception for ESPN's Sport Science. Here is part 2 of Sport Science trying to reproduce Kobe Bryant's "jumping over a car" stunt.
And here is part 1 (although part 2 is the only interesting part). See. I can get along with Sport Science. Anyway, I am not sure that Kobe's jump used wires - but I assumed it was fake. Here is my analysis of Kobe's Jump (this stuff is old). And this is the plot I created from video analysis of Kobe.
The tough thing about looking at Kobe's jump is that he changes his body…
drorzel | April 28, 2010I'm teaching Physics 350: Quantum Mechanics this term, which is a junior/senior level elective course using Townsend's book which deals with quantum mechanics in the state vector formalism. The room in which the class meets is the only one in the department that contains a whiteboard (using dry-erase markers) rather than a blackboard (using chalk).
In the first several weeks of the course, I have mostly been using blue markers, because that's what's been in the room. These fade into illegibility very quickly, so today I went into the stockroom to get more, and discovered a box of black…
rallain | April 28, 2010You see in my experimental determination of the location of the accelerometer in an iPod, I used two different iPhone apps. Let me briefly mention some of the free iPhone apps that give you acceleration data.
AccelGraph: This is one of the apps I actually used. What do I like about it? Well, it can record x, y, and z acceleration data and then you can email it to yourself. What could make it better? How about a timed start to record (like start recording in t seconds) and a preset record time. This would allow you to set up your experiment and get your iPod set up before you start. As…
rallain | April 27, 2010There are several free iPhone-iPod Touch apps that let you look at the acceleration of the device using the built in accelerometer. I was planning on reviewing some of these free apps, but I didn't. When I started playing around with them, it was clear that I needed some way to make a constant acceleration. There are two simple ways to do this - drop it, or spin it in a circle. I decided to go with the circular motion option because I like my iPod and because Steve Jobs told me to.
While playing with this, I realized that the acceleration depends on the distance of the sensor from the…
drorzel | April 27, 2010Dennis Overbye has a piece on "The Big Bang Theory" in today's New York Times, taking the "Is this good or bad for science?" angle:
Three years later some scientists still say that although the series, "The Big Bang Theory" (Monday nights on CBS), is funny and scientifically accurate, they are put off by it.
"Makes me cringe," said Bruce Margon, an astrophysicist at the University of California, Santa Cruz, explaining, "The terrible stereotyping of the nerd plus the dumb blond are steps backwards for science literacy."
But other scientists are lining up for guest slots on the show, which has…
drorzel | April 26, 2010As of 1:45 Monday, 217 people have cast votes in the Laser Smackdown poll. That's not bad, but it's currently being handily beaten by the 271 people who have voted for a favorite system of units.
The nice thing about using actual poll services for this sort of thing, though, is that I can re-post the poll to boost signal a little. So, here it is again, a list of the twelve most amazing laser applications suggested by my wise and worldly readers, with links to short explanations of the pros and cons of each:
Which of the following is the most amazing application of a laser?Market Research…
rallain | April 26, 2010I meant to mention this earlier since it happened a little while ago. There is this "mini-conference" with three schools: Southeastern Louisiana University, Southern Mississippi University, and the University of South Alabama. The purpose is to give students (and some faculty) a chance to present their work at a smaller conference. I really enjoy this, mostly because it is small and I get to see lots of undergrad talks. There are two talks that stuck in my head.
Dr. Jiu Ding "Dynamical Geometry: From Order to Chaos and Sierpinski Pedal Triangles"
Jiu Ding is a mathematics professor at…
rallain | April 24, 2010Check this out.
So, the guy jumps from 150 feet into some cardboard boxes. Why are the boxes important? You want something that can stop you in the largest distance to make your acceleration the smallest. Here is my Dangerous Jumping Calculator. Basically, you put in how high you will jump from and how much distance you will take to land and it tells you your acceleration.
You will probably need this G-force tolerance info from wikipedia.
One problem - this calculator doesn't really work for this case. It doesn't take into account air resistance. Does air resistance even matter in this…
pontiff | April 23, 2010What prefix do you use for 1027? If Austin Sendak has his way, it will be hella (also Time article here.) The diameter of the observable universe is about one hellameter. As a fellow member of the club "people from Yreka, CA who do physics," I strongly support Austin's idea. Indeed it now tops my list of proposed prefix changes, a list that includes "tiny-" for 10-5 and my former front runner for 1027 "bronto-."
But the real question is what do we call 10x when we don't know x? I suggest the prefix "huh". Examples: "My answer of about 5 huh-people wasn't good enough to land me a job at…