Physics
rallain | July 21, 2010Frank Noschese is a physics teacher and a blogger (and frequent commenter on Dot Physics). And I nominate Frank as the new librarian of videos that can be analyzed for realness or fakeness. Or, as Frank calls them Win-Fail Physics. Note that I sort of changed his theme a little - sorry Frank.
Win-Fail physics videos are all over the place. You know I like these things. They are videos that look cool and people question if they are real or fake. Sometimes it is easy to tell, sometimes it takes a little analysis, and sometimes it is very difficult to tell (and I get it wrong).
So, here is…
esiegel | July 21, 2010He was a dreamer, a thinker, a speculative philosopher... or, as his wife would have it, an idiot. -Douglas Adams
When I started writing about science online in January of 2008, I put the word out that I would accept questions from my readers. After all, I knew that there was a lot of misinformation out there, as well as the more insidious "technically correct but misleading" information about science.
In particular, I want to get the actual information that we know out there. As far as what I can contribute, I'm confident that I can add an expert voice for my specialties (physics, astronomy…
drorzel | July 21, 2010Here's a picture of the ornamental pond we have in our back yard, showing the fountain that we run to keep the water circulating so it's not just a mosquito ranch:
You can see the brick that we have sitting on top of the pump housing to keep it submerged (it tends to tip over otherwise-- the filter box is a little top-heavy), and also the spray of water shooting up into the air.
You can't tell without some reference, but the pond level is actually a little lower than I like it at the moment. The lining leaks slowly, and every so often I need to put more water in. How do I judge the level,…
drorzel | July 21, 2010If you're in the UK, you may very well be thinking "You know, I love the idea of How to Teach Physics to Your Dog, but I find American idiom very intimidating. If only there were an edition just for people like me..."
Well, hypothetical UK person, your prayers have been answered:
This is the cover for How to Teach Quantum Physics to Your Dog, coming this fall from Oneworld books to a bookshop on the high street near you. With "yard" changed to "garden," and other minor linguistic tweaks to make it more comprehensible in Merrie Olde England and other such places. Also, an index, which the…
drorzel | July 20, 2010Yesterday's post about how nobody cares about condensed matter physics produced a surprising number of comments of the form "I was really hoping you would post about topological insulators," which surprised me a bit. Anyway, since people asked for it, I'll give it a shot. The important caveats here are that 1) this isn't my field, and 2) I have not read a great deal of the primary literature on this, so my understanding is not that deep.
We'll do this in Q&A format, as that's been working well for ResearchBlogging posts lately.
So, what's a "topological insulator," anyway? You make a…
rallain | July 19, 2010(alternate title: how to make pretty graphs in vpython)
I am happy. Finally, I can use the visual module in python (vPython.org) and plotting with Matplotlib. Maybe this isn't such a big deal for many of you, but for me, it never worked until now.
In the past, I blogged about plotting in vpython vs. matplotlib. My conclusion was that it was easier in vpython, but prettier in matplotlib. So, why not just use matplotlib? There are a couple of things that make vypthon very attractive.
Vectors. Vpython has a built in vector class (or function - I don't know what I am talking about). There…
drorzel | July 19, 2010I had planned to spend some time this weekend trying to make sense of this new result on topological insulators, and maybe even write up the relevant paper for ResearchBlogging. Family life intervened, though, and I didn't have the time. I get enough of it to understand the basics of what's going on, but there's a whole lot I don't understand about topological insulators generally, so I'd need to do a bunch of reference chasing to get to something I can understand well enough to work back up to this week's Nature paper.
And, to put it bluntly, there just isn't that much reward for the work…
drorzel | July 19, 2010Over at Jeff Vandemeer's blog, Rachel Swirsky has a series ofm guest posts (start here if you prefer direct post links) about the recently completed Launch Pad workshop. this is a NASA funded workshop bringing a group of writers together for six days of lectures on modern astronomy from working astronomers. From the workshop web site:
Launch Pad is a NASA-funded education/public outreach effort supplementing Mike Brotherton's space-based astronomical research. Our budget allows us to provide a workshop that is essentially free to participants. Our primary goal is to teach writers of all…
esiegel | July 16, 2010"If you only look at a person through one lens, or only believe what you're told, you can often miss the truth that is staring you in the face." -Kevin Spacey
One of the most powerful ideas from Einstein's theory of Gravity -- General Relativity -- is that any massive object in the Universe not only causes a gravitational force on other masses, but also bends light!
Image credit: Dave Jarvis of http://davidjarvis.ca/dave/gallery/.
(Link to David Jarvis' gallery.) This was confirmed in 1919 by observing the positions of stars during a total solar eclipse; the stars closest to the Sun had…
drorzel | July 15, 2010In the comments following the silly accelerator poll, onymous wrote:
[T]he point of the LHC isn't to discover the Higgs. No one in their right minds would build a 14 TeV pp collider if their only goal was to discover the Higgs.
While it's true that the ultimate goal of the LHC is to discover more exotic particles that may or may not exist (blah, blah, supersymmetry, blah) most of the hype has focussed on the Higgs, which is the one thing they're pretty sure they'll find (comments later in that thread notwithstanding). This is one of the potential problems with the way the machine has been…
esiegel | July 14, 2010"I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use." -Galileo Galilei
Geez, Ethan, why don't you take on a bigger question?
This question of "fundamental things" has a special meaning to scientists and natural philosophers, going all the way back to Thales of Miletus, 2600 years ago, who began asking about the arche (αρχή), which is the "element" or "prime cause" of existing things.
Of course, the scientific enterprise was just beginning, so you can't fault Thales too much for coming up with "water". But…
drorzel | July 14, 2010With the rumors of a Higgs Boson detected at Fermilab now getting the sort of official denial that in politics would mean the rumors were about to be confirmed in spectacular fashion, it's looking like we'll have to wait a little while longer before the next "Holy Grail" of physics gets discovered.
Strictly speaking, the only thing I recall being officially dubbed a "Holy Grail" that's been discovered was Bose-Einstein Condensation (BEC), first produced by eventual Nobelists Carl Wieman and Eric Cornell in 1995. Somebody, I think it was Keith Burnett of Oxford, was quoted in the media calling…
jhalper | July 14, 2010Bats may be using an innate understanding of physics to track their prey in the dark. Institute neurobiologists trained Egyptian fruit bats to fly to food in a dark lab. They found that in some situations the bats sweep their sonar to either side, catching their "prey" on the beam's slope, while at other times they point their beams head-on. Some physical calculations showed that the changes in intensity near the slope help in getting a fix on the target's direction - a very efficient strategy for localizing targets - while the direct beam is preferable for discerning a hard-to-identify…
rallain | July 13, 2010Here is a commercial for some Mercedes car. The first part is quite boring, but check out the stunt at around 2:00 minutes into the video.
I haven't bothered to check if this is officially fake or not. Instead, I will do what I do - see if this is even feasible.
The common question people ask when they see something like this is: "how does the car defy gravity?" Well, it doesn't. Why doesn't it fall? In a sense it does. This is essentially the same as spinning a bucket of water over your head. Maybe a diagram of the car at the top of the tunnel will help.
I tried to make the car stand…
rallain | July 13, 2010The other day I found myself faced with six equations that needed to be solved algebraically. Just so you know, I am a big fan of paper for most of these cases - but this was out of control. I was making silly mistakes and causing all sorts of problems. What to do? My first though was to use some symbolic plugins for python. I tried sympy and it is nice. However, it was not giving correct solutions for solving 3 equations - I don't know if this is a bug or what.
Maxima
I think I found Maxima through Wikipedia's Computer algebra system page. It's free and free and runs on Mac OS X and…
drorzel | July 13, 2010Yesterday's poll about "outreach" activities drew 117 responses by this morning. Since PollDaddy stupidly calculates percentages for ticky-box polls based on the number of total selections, not the number of people who vote, the graph you get when you view the results is kind of useless. A better version, using the "CHECK THIS BOX" count, is here:
These responses line up reasonably well with my own impressions of the term. I'm a little surprised that "Demo Shows" doesn't get 100%, even if you factor out the three people who clicked "I would not deign to know what outreach is." This probably…
drorzel | July 13, 2010It looks like I may well be getting together with some friends from college in Alabama on the first weekend in October, to go to a college football game. The logistics of getting to Tuscaloosa make this seem like an awfully long weekend, but I would feel guilty taking two days off just for football and college nostalgia.
It occurs to me, though, that the state of Alabama contains many fine educational institutions, which must have physics departments and students. If any of them would be interested in hearing a talk from me (I can talk about research (single-atom trapping for radioactive…
esiegel | July 12, 2010Yo ho! It's hot, the sun is not a place where we could live.
But here on earth there'd be no life without the light it gives.
We need its light. We need its heat. We need its energy.
Without the sun without a doubt there'd be no you and me. -They Might Be Giants
Ahh, the Sun. Beautiful and blinding to the naked eye, it's still the source of energy that gave rise to all of the life on Earth that we know.
Image credit: GOES satellite, in the X-ray.
The Sun emits energy all over the light spectrum, from long-wavelength radio waves (many meters long) to visible light to X-rays (just a small…
drorzel | July 12, 2010Rumors that the Tevatron at Fermilab may have discovered the Higgs boson have escaped blogdom to the mainstream media. This originates in a blog post by Tommaso Dorigo, which I can't read because it doesn't display properly in Firefox, but I'm sure is very interesting.
Anyway, this is a good excuse for a dorky poll:
If the Tevatron were to discover the Higgs boson before the LHC does, that would be:Market Research
There's a 99.7% probability that this poll is completely meaningless. That doesn't mean it's not entertaining, though.
drorzel | July 12, 2010I spent this weekend in Baltimore for the summer meeting of the Committee on Informing the Public, held at the Maryland Science Center, which is a really nice science museum. This has left me feeling jet-lagged, a neat trick when I never left the Eastern time zone, but perhaps Saturday's visit to Pub Dog had something to do with it...
We had a number of discussions about the meaning of the word "Outreach" in a physics context, which is one of those Damon Knight/ Potter Stewart, "I know it when I point at it" kind of terms. I'm interested in what opinions people outside the committee have,…