Physics
drorzel | October 29, 2013Two papers with a similar theme crossed my social media feeds in the last couple of days. You might think this is just a weird coincidence, but I'm choosing to take it as a sign to write about them for the blog.
So, what are these papers, and what's the theme? One is the final publication of some results I saw at DAMOP and alluded to back in June, and the other is from this post by Doug Natelson. Both look at the transition from few-body to many-body physics.
And this is interesting, why? I mean, isn't it obvious that you just add some more bodies? OK, I guess that does need a little more…
drorzel | October 28, 2013A couple of weeks back, DougT won this year's Nobel betting pool, and requested a post on the subject of funding of wacky ieas:
could you comment on this: http://www.space.com/22344-elon-musk-hyperloop-technology-revealed.html and the phenomenon of the uber-rich funding science in general. It seems to me that there used to be more private funding of science, and there still is a lot. But is government funding crowding out private funding (political question), is government funding necessary for Apollo and CERN b/c it’s so huge, is private funding more “out there” and therefore on the tails of…
esiegel | October 25, 2013"I have just gone over my comet computations again, and it is humiliating to perceive how very little more I know than I did seven years ago when I first did this kind of work." -Maria Mitchell
Well, it's getting close to the end of October, the Moon is waning towards its new phase, and -- at least in the northern hemisphere -- the days are getting shorter and the nights are lengthening. Is there anything unique on its way that's worth watching the skies for? In today's Ask Ethan column, our suggestion comes from longtime reader and commenter Sinisa Lazarek, who inquires:
Since ISON comet is…
drorzel | October 25, 2013It's that time of year again when people start thinking about Halloween costumes-- SteelyKid is apparently planning to re-use her Peter Pan outfit from last year-- and the conceptual costumes post from a while back has proved enduringly popular at this time of year. If you're not into conceptual art, though, maybe some historical cosplay is more your thing, so here are some totally serious ideas if you want to go to your local physics department's Halloween party as one of the great physicists of the last half-millennium.
Sexy Niels Bohr
This was actually the trigger for this post, when…
drorzel | October 24, 2013Via social media, John Novak cashes in a Nobel Betting Pool win from a while back, asking:
Please explain to me the relationship between energy, entropy, and free energy. Like you would explain it to a two year old child.
Why? There is a statistical algorithm called Expectation Maximization which is often explained in terms of those three quantities. But apparently entropy is hard to understand because all the detail in the analogy is heaped on entropy part (with some side tracks in Kullback-Leibler divergences.) Since I have a background in communication theory, entropy is a perfectly…
esiegel | October 23, 2013"Bad men need nothing more to compass their ends, than that good men should look on and do nothing." -John Stuart Mill
No one becomes a master overnight, and practically no one does it without the outside help and support of not just a mentor, but of a number of peers, advisors and other allies along the way. At least, that was my story.
Image credit: University of Baltimore.
I remember being an undergraduate. I remember the combined struggles of rigorous academics, self-confidence crises, trying to figure myself out as a person, and trying to make friends and forge relationships all at…
drorzel | October 22, 2013When I posted congratulating the winner of this year's Nobel betting pool, I received a gentle reminder in email that I'm a Bad Person and still haven't done one of the posts I owe to the 2011 winners. Evan reminded me that he asked for something about the delayed-choice quantum eraser, so let's talk about that a bit, in the traditional Q&A format.
So, what's a delayed choice quantum eraser do? It may or may not have rubbed out mistakes you made while writing, but you don't know until later when somebody else chooses to read it? Nothing physical gets erased. The delayed-choice quantum…
drorzel | October 21, 2013Having spent a bunch of time talking about heavy stuff in the science blogging community, let's unwind a bit and kick the week off with a look back at an old Master's thesis. This one is from 1932, and is almost certainly a draft copy, because it's extremely cheaply bound in cardboard with the title hand-lettered on the front. There are a few corrections in the text as well, which is very short-- just 11 pages, not counting the figures at the end.
Again, this is interesting as much for what it doesn't contain as what it does. The subject matter is pretty mundane by modern standards-- just…
esiegel | October 18, 2013"If you are writing any book about the end of the world, what you are really writing about is what's worth saving about it." -Justin Cronin
Well, it's Friday again, and that means it's time to dip into the question/suggestion box, and see what you've come up with for me. This week's Ask Ethan comes from our reader Michael Acosta, who wants to know about the end of the world. Not, mind you, the way the world is actually likely to end, but in a way that would be satisfying to an aspiring science fiction writer.
In this wonderful science fiction book I am writing, there is a subplot involving…
drorzel | October 18, 2013Yes, that's another TED@NYC picture as the "featured image," but don't run away! It's a post about science, I swear!
The photo up above is from the Flickr set (which, by the way, has been edited significantly since yesterday...), and I like it a good deal. Mostly because, as the joking caption suggests, that photo of Max Planck looming over my head has a kind of serial killer vibe to it. But here's the thing: this is the original phtoo that's on the slide:
Max Planck around the time he solved the black-body radiation problem. From wikimedia.
It's a black-and-white photo from 1901, and in…
esiegel | October 17, 2013"It is not when truth is dirty, but when it is shallow, that the lover of knowledge is reluctant to step into its waters." -Friedrich Nietzsche
Although the innermost planets, from Mercury through Saturn, were known since ancient times, it's only since the advent of the telescope that we've discovered what really lives in our Solar System. Over the past four centuries, the wonders of not only the distant Universe, but also our nearby neighborhood, have been uncovered in spectacular detail.
Image credit: NASA and – I believe – G. Bacon (STScI).
The third and fourth largest planets were…
drorzel | October 17, 2013As noted in a previous post on Monte Carlo simulation in 1960, we recently came into possession of a large box of old Master's theses. The bulk of these are from the 50's and 60's, but there are some going back much farther. As I pass these every day I'm in the office, I thought it might be amusing to take a look at these for the blog, now and again. I don't plan to do a detailed examination of the quality of the science (at least, not necessarily), but to use this to look at how things have changed over the decades.
The first of these, pictured above, is one of the oldest: Secondary Emission…
drorzel | October 16, 2013The Twitter conversation that prompted yesterday's post about composite objects was apparently prompted by a comment somebody made about how a virus left alone would see its quantum wavefunction spread out on a time scale of minutes. This led to wondering about whether a virus could really be considered a particle that would move as a single quantum unit, and then to whether that estimate is reasonable. So, let's look at that specific question a little more closely. This is going to be one of those swashbuckling physicist estimation deals, in which I'm going to attempt to come up with numbers…
drorzel | October 16, 2013Back in July, Physics Today ran an article on Reinventing physics for life-sciences majors (I couldn't find an un-paywalled version, but this arxiv preprint seems to be close to it). As I've had some bad experiences with that class, I flagged it as something to read, but only got around to it last night. The main idea is that a "Physics for Life Sciences" course needs to be arranged around the way biologists think, which is fundamentally different than the way physicists think:
In general, physicists stress reasoning from a few fundamental principles—usually mathematically formulated—and seek…
drorzel | October 16, 2013The nice folks at TED have put up a giant Flickr set of pictures from last week's event. I'm not sure it's complete, but I happened to notice it this morning, and it already had several pictures of me in it, which is all I really care about. I particularly like the "featured image" above, which kind of makes me look like some kind of quantum demagogue urging my electrons on to more efficient production of interference patterns like the one over my shoulder.
But I also like this one, in which a deranged Max Planck looms behind me like a serial killer:
Max Planck knows what I did last summer…
drorzel | October 15, 2013I'm doing a bit of work on an idea for physics outreach, which would involve tying a discussion of modern physics to science fiction stories. I have Opinions about this sort of thing, of course, but I also have readers who might think of things I don't. So, let me throw this out to you all:
What is your favorite example of a science fiction story (here meaning print, movie, or television) making use of ideas from quantum physics? What's your least favorite?
My favorite stories invoking QM ideas are probably Robert Charles Wilson's brilliant "Divided by Infinity" (which I will draw heavily on…
drorzel | October 15, 2013Through some kind of weird synchronicity, the title question came up twice yesterday, once in a comment to my TED@NYC talk post, and the second time on Twitter, in a conversation with a person whose account is protected, thus rendering it un-link-able. Trust me.
The question is one of those things that you don't necessarily think about right off-- of course an atom is a particle!-- but once it gets brought up, you realize it's a little subtle. Because, after all, while electrons and photons are fundamental particles, with no internal structure, atoms are made of smaller things. But somehow we…
drorzel | October 14, 2013The TED@NYC trip took me to Manhattan on Monday for the run-through of my talk that night, but then I was left in The City all day Tuesday with time to kill. My original plan was to go to the Guggenheim Museum, as I've never been there and it's an iconic building, but there was a note on their web page that the ramps were closed in preparation for some exhibit, and I figured that would sort of ruin the point, so I went to the Museum of Modern Art instead.
If you know me at all, those might seem odd choices, as modern art really isn't my thing. The MOMA is heavy on pieces that "Call into…
jhalper | October 12, 2013Of the four new articles online on our website, three happen, purely by accident, to be on physics research. The three are very different, and yet each is an illustration of the ways that basic physics research changes our world – in small and large, practical and enlightening ways. And each is situated at a different intersection between the technological and the theoretical – a technological breakthrough that resulted from a successful attempt to provide proof for a theoretical construct, new inventions based on elementary physical principles of light, and a theory substantiated through a…
drorzel | October 11, 2013I'm sure I've done more than enough wibbling about TED for this week, but the only major physics story at the moment involved the Higgs boson, and I'm thoroughly sick of that. So let's talk about Malcolm Gladwell and journosplaining.
Gladwell has a new book out, David and Goliath that from all reports is pretty much exactly what you expect from a Malcolm Gladwell book. I greatly enjoyed the digested read by John Crace in the Guardian. Among the many bad reviews of this were a trio by my colleague at Union, Christopher Chabris-- first a paywalled review in the Wall Street Journal, then a post…