Physics
drorzel | February 2, 2010Just about everybody has heard of the Twin Paradox in relativity: one twin becomes as astronaut and sets off for Alpha Centauri, the other remains on Earth at mission control. Thanks to time dilation, the two age at different rates, and the one who made the trip out and back ends up younger than the one who stayed behind.
Of course, the paradox is not that the two twins have different ages-- rather, it's that from a simple approach to special relativity, you would think that each twin should see the other's clock running slow, since it seems like getting into a rocket and flying off into…
drorzel | February 2, 2010Tuesday is a heavy teaching day for me-- I'm in lab from 9-4, basically-- so here's something to occupy the time. Oh, no! It's a pop quiz:
Pop quizzes are:(survey software)
(In case the phrase is an American idiom, a "pop quiz" refers to a short test given in class with no advance warning.)
This was inspired by Dermot O'Brien at Inside Higher Ed, who reports on taking his first quiz as a science student. The general topic of quizzes is one that generates a fair bit of heat, though, so I thought I'd see what my readers think of it.
My quiz policy as of a year or so ago was to give many short…
drorzel | February 2, 2010Congratulations to Alain Aspect, John Clauser, and Anton Zeilinger for winning the 2010 Wolf Prize in Phyiscs:
The 2010 Wolf Prize in Physics will be shared by Prof. John F. Clauser of the US; Prof. Alain Aspect of France's Ãcole Normale Supérieure de Cachan; and Prof. Anton Zeilinger of the University of Vienna. The jury in this field praised them "for their fundamental conceptual and experimental contributions to the foundations of quantum physics, specifically an increasingly sophisticated series of tests of Bell's inequalities, or extensions thereof, using entangled quantum states."
All…
drorzel | February 1, 2010Last week, I asked for nominations of the most amazing laser application, with the idea being that I will collect a list, write up the top vote-getters in a series of blog posts, and then we will have a vote to determine what is THE coolest laser application of ALL TIME!
At least, you know, as far as you can do that on a blog...
Nominations will remain open until next Monday, but I wanted to remind people, and give you a list of the top nominees thus far. These will be pretty hard to top, but there are still lots of laser applications that have not been mentioned, so be sure to get your vote…
drorzel | February 1, 2010Two events in the next couple of weeks at which I will be appearing live and in person:
1) This Thursday, Feb. 4, I will be giving a talk at the University of Maryland, College Park at 3:30 pm in the Lecture Hall (room 1110) in the Kim Engineering Building. The title of the talk is "Talking to My Dog About Science: Why Public Communication of Science Matters, and How Weblogs Can Help." Which reminds me, I need to tweak those slides...
Lest I get overly nostalgic about Our Nation's Capital, there's snow predicted for Friday and Saturday, just in time to potentially screw up my flight home.…
drorzel | January 31, 2010The Firedoglake Book Salon with Sean Carroll last night was a lot of fun. I was generally impressed with the level of the questions, and the tone of the discussion. We went through all of the questions I had typed out in advance (I type fairly slowly, and revise obsessively, so it's hard for me to do this stuff in real time), and got a decent range of questions from the audience.
The introductory post I wrote for the salon is more or less what I would put in a review post here:
ean Carroll's From Eternity to Here sets out to explain the nature of time, particularly what's known as the "arrow…
drorzel | January 30, 2010A few bits and pieces of news regarding How to Teach Physics to Your Dog:
We got and accepted an offer for the audio book rights from one of the biggest audio book publishers. Actually, I think there were two offers for the audio rights, which is amazing. I have no idea when it would be produced or who would read it, but the contract does say they'll consult with me about the reader, so I'll know at some point before it comes out...
Speaking of other editions, I'm getting emails from my publisher about the paperback edition already, which just seems weird. The hardcover's only been out for a…
drorzel | January 29, 2010Hard to believe it's been a couple of days since I posted anything with this title... Anyway, there are a couple of small updates:
The vanity search turned up this mention on ScienceBase, in with a bunch of other recent science books that sound pretty good.
The Union student paper, the Concordiensis, has a story about the book. I exchanged emails with the author, so it has a couple of new quotes that haven't been in other papers.
Once again, if you're in New York's capital district tomorrow, I'm doing a signing at the Book House at 2pm. If you're not in the Albany area, I'll be the host for…
drorzel | January 28, 2010Last week's Seven Essential Elements of Quantum Physics post sparked a fair bit of discussion, though most of it was at the expert level, well above the level of the intended audience. such is life in the physics blogosphere.
I think it's worth a little time to unpack some of the disagreement, though, as it sheds a little light on the process of writing this sort of thing for a general audience, and the eternal conflict between broad explanation and "dumbing down." And, if nothing else, it lets me put off grading the exams from last night for a little while longer.
So, what's the issue? The…
drorzel | January 28, 2010I've toyed around in the past with ways to use the Amazon sales rank tracker to estimate the sales numbers for How to Teach Physics to Your Dog. It's geeky fun, but not especially quantitative.
Yesterday, though, I found a reason to re-visit the topic: calibration data!
OK, "calibration data" is probably too strong a description. "Calibration anecdote" is more accurate.
Yesterday when I went into work a little after 10, a comment somebody made sent me to the actual Amazon page for the book, where I saw a little note next to the price information saying "Only 5 left (more are coming)-- order…
rallain | January 27, 2010This is actually been sitting around for a while waiting for me to post it. Here is another short Christmas-toy demo. I am going to pull this yo-yo at different angles and on two different surfaces. Check it out.
What is going on here? Let me look at the first case where I pull the yo-yo and it slides without rolling. Here is a diagram.
Normally, I would just say - "hey - a free body diagram". And this is one, but you have to be careful. Normally, a free body diagram treats an object as though it were a point mass. You can't do that in this case because you have to consider rotation…
drorzel | January 27, 2010Two upcoming events related to How to Teach Physics to Your Dog:
This Saturday, January 30, I will be doing a signing at 2pm at the book House of Stuyvesant Plaza, on Western Ave. in Albany. I may or may not read something-- I'm not entirely sure what I'm supposed to do as part of this, never having done a book signing before.
Next Thursday, February 4th, I'll be giving a talk sponsored by the Maryland Chapter of SPIE at 3:30 pm in the Lecture Hall (room 1110) in the Kim Engineering Building. The title of the talk is "Talking to My Dog About Science: Why Public Communication of Science…
milhayser | January 27, 2010
Love it or hate it, physics is a demanding subject. It defines much of our knowledge and experience in a daunting variety of ways. But really, you do love physics, don't you? On Uncertain Principles, Chad Orzel describes a modern implementation of "Maxwell's Demon," a dreamed-of 19th century device that could "cool a gas without obviously increasing entropy." While this may smack of perpetual motion, researchers have taken first steps toward realizing Maxwell's mechanism, using angled traps and lasers to winnow lower-energy atoms from a gas sample. On Starts With A Bang, Ethan Siegel…
drorzel | January 27, 2010Via SFSignal's daily links dump, Lilith Saintcrow has a terrific post about the relationship between authors and editors:
YOUR EDITOR IS NOT THE ENEMY.
I don't lose sight of the fact that I am the content creator. For the characters, I know what's best. It's my job to tell the damn story and produce enough raw material that we can trim it into reasonable shape. (Which means I am responsible for my deadlines, but we knew that.) I'm also way too close to the work to be able to see it objectively. So, 99% of the time, the editor is right.
Read it. It's good, and very true.
"Yeah, but that's…
drorzel | January 27, 2010Dennis Overbye is a terrific writer, but I have to say, I hate the way that he falls into the lazy shorthand of using "physics" to mean "theoretical particle physics" in this article about a recent conference built around debates about the state of particle physics. He's got lots of great quotes from Lisa Randall and Lawrence Krauss and others about how things are really bleak on the theory side, and these are barely tempered by enthusiasm from experimentalists.
So, yeah, theoretical particle physics may well appear to be in crisis. But, look, theoretical particle physics is always in crisis…
drorzel | January 26, 2010A few days back, Matthew Beckler added the Kindle edition to his sales rank tracker for How to Teach Physics to Your Dog. Given my well-known love for playing with graphs of data, it was inevitable that I would plot both of these in a variety of ways.
So, what do we learn from this? Well, we learn that people in the Albany. NY area don't own Kindles:
OK, maybe that's not obvious to everybody...
When you look at that graph, the blue line is the Amazon sales rank of the physical book edition, while the red line is the Amazon sales rank of the Kindle edition. The two track each other pretty…
drorzel | January 26, 2010Way back in the early days of ScienceBlogs, I ran a competition of sorts to determine the greatest physics experiment in history. I collected a bunch of nominations, wrote up a post about each of the top 11 entries, and then asked people to vote for their favorite.
In honor of the 50th anniversary of the laser, let's take a stab at something similar:
What is the coolest thing you know of that's done with lasers?
Lasers are all over the place these days, from UPC scanners to telecom networks to optical drives to hospitals. All sorts of fascinating things have been done with lasers over the…
drorzel | January 25, 2010The great thing about using Google to vanity search for articles about How to Teach Physics to Your Dog, or at least one of the great things about it, is that it's world-wide. Thus, this Dutch roundup of new books, which includes mine. This is what they have to say:
Een erg geestig boek is 'How to Teach Physics to Your Dog'. Chad Orzel gebruikt scenarios uit de echte wereld om kwantummechanica uit te leggen. Dit doet hij dankzij conversaties met zijn hond Emmy. De leuke gesprekken zorgen er voor dat veel vragen worden opgelost over kwantummechanica. Het boek is niet voor de absolute beginner…
drorzel | January 25, 2010As mentioned previously, I've been reading Sean Carroll's Wheel arrow of time book, which necessarily includes a good bit of discussion of "Maxwell's Demon," a thought experiment famously proposed by James Clerk Maxwell as something that would allow you to cool a gas without obviously increasing entropy. The "demon" mans a trapdoor between a sample of gas and an initially empty space, and allows only slow-moving gas atoms to pass through. After some time, the empty volume is filled with a gas at lower temperature than the initial sample, while the gas in the original volume is hotter than…
drorzel | January 25, 2010There was a flurry of stories last week about an arxiv preprint on optical trapping of an ion. Somewhat surprisingly for an arxiv-only paper, it got a write-up in Physics World. While I generally like Physics World, I have to take issue with their description of why this is interesting:
In the past, the trapping of atomic particles has followed a basic rule: use radio-frequency (RF) electromagnetic fields for ions, and optical lasers for neutral particles, such as atoms. This is because RF fields can only exert electric forces on charges; try to use them on neutral particles and there's…