Better To Burn Out, Or To Fade Away?

On the site Space.com, I found a nice article by David Powell about the Cassini spacecraft’s future. (Cassini has done some wonderful work recently, including bringing us wonderful images such as the one below of Titan and Epimetheus, and Saturn’s rings.)

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Cassini’s NASA handlers are wondering about what they will do with it when its mission is over. Here are some of the options they are considering:

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The 2006 Nobel Prizes: Who, What and Why!

Not long after the colloquium on the Fields Medal work, we had a joint presentation by three colloquium speakers on the topics of the three science prizes awarded from the good folks in Stockholm this year. This was another very popular Monday talk, with people from various other departments joining us, given the topics being discussed. The speakers talked about the science of the prizes, and also reflected upon how it drives or interfaces with future research, perhaps their own research program.

First up was Lin Chen, of Chemistry and Molecular and Computational Biology. He told us about the Chemistry prize, awarded to Roger Kornberg, “for his studies of the molecular basis of eukaryotic transcription”.

Starting out by reminding us about the basic chain of relationships within organisms concerning the movement of genetic information, (the “Central Dogma”) he explained […] Click to continue reading this post

More Scenes From the Storm in a Teacup, VI

A quick update:

* There was a second installment of the discussion led by George Johnson about press coverage of string theory. He went back to look to see what exactly some of those early articles said… How much coverage was there to start with? When did it start? When did it begin get out of hand? Did it get out of hand? Is this all just part of a standard bubble that happens for any field that the press decides to cover, a sort of manufactured (my word not his) boom and bust cycle? All issues that were touched upon in the discussion. Note also that the discussion broadens out considerably -as it should, (finally!)- to talk about the broader issue of coverage of topics in physics and science in general. The positive and negative effects of press coverage on attracting the next generation of students was also discussed. The discussion (this aspect in particular) was especially interesting because of the remarks by a number of senior people in the audience who were able to talk about their experiences over the years having seen the cycles recruitment of students in their own departments. Worth a listen/look at the archive here.
* Lee Smolin has written a “Dear Friends” letter in response to some of the things that have been pointed out about his book, and about other points he’s made publicly in various discussions. He’s given over some time to write quite a bit, which in general is a good thing to have done. You can find it here.

I’ll leave it to you to form your own opinion about Smolin’s remarks (I’ve not had time to read it in detail yet), and start a discussion here. Maybe ask him some followup questions here, for example. To help with context and build a more complete picture, do read some of the earlier comments and discussions involving him -and questions put directly to him- on the threads that share the name of this post. (e.g., Here and here.) Put those alongside the discussion with Peter Woit and of the central thesis of Woit’s book too. They are inseparable.

My set of opinions on the issue is the same as it was before. Even though I’ve said it all so many times here, since blogs seem to have no memory, I will summarize a bit:

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Mercury Passing

transit of mercury

So did you see yesterday’s event? (Above is a snapshot of a movie of the event from a SOHO image capture sequence. Mercury is a tiny dot just below the structure on the right that is not far from one of the remarkably few sunspots on the sun at present (it is low season for them). Go there for more images to see Mercury in action.)

Joe Vandiver (centre, below) here at USC had a telescope set up for all on campus to view: […] Click to continue reading this post

Elemental

Yesterday in Physics 100 we started a discussion of the structure of matter. This inevitably brings up the early ideas from 400 BC about atoms, from Democritus (and others) at least in the Greek line of thought. These ideas were later brushed aside by Aristotle who declared that the elements from which everything can be constructed were Earth, Air, Fire, and Water.

Of course, one is obliged to show a slide at this point. I could not resist this one: […] Click to continue reading this post

A Man Out Standing In His Field

Two of our colloquia this semester were concerned with work very much in the public eye this year. The first was from Francis Bonahan of the Mathematics Department here at USC.

F bonahan colloquium

He talked about the work that won the Fields medal – the proof, by Grigori Perelman, of the Poincaré conjecture. Or better, I should say the work toward the proof, since the citation does not explicitly mention the conjecture, but his larger body of work. (MathWorld link, Wikipedia link.) In fact, Francis spoke about a lot more than just the Poincaré conjecture. He talked about the larger setting in which that work fits, something mathematicians call the “geometrization conjecture”, which Mathematicians care a lot more about. Perelman’s work does more than just prove the Poincaré, it addresses the whole (3-)ball of wax, so to speak. He told us quite a bit about that in the talk, spending most time talking about what they were and how they fit into the scheme of things, rather than […] Click to continue reading this post

Twelve Days of Physics

This morning I received an email from someone called “Grrrl Einstein” today which read:

I am creating a Physics Calendar for the Holiday season, and I am including twelve entities. So far I have:

  1. Newton’s Laws
  2. The Dirac equation/Schrodinger equation
  3. The Clifford Algebra defining the Dirac gamma matrices
  4. E=mc2/Einstein’s equations/postulates and/or some solution of them, such as the Schwarzschild solution
  5. The principle of least action
  6. Maxwell’s equations
  7. E=hv
  8. The Yang-Mills Lagrangian
  9. The Schwinger-Dyson equations or something else related to functional methods
  10. Stokes’ Theorem
  11. Entropy

What would be a good String Theory equation to round it out? Any things I should include/exclude?

She also says: […] Click to continue reading this post

Copernican Reality

Well, you’re sitting there at the desk, so might as well put on the radio to keep yourself company. Do in on the web, and I suggest that you listen to:

Radio Lab episode #205

This one was about Space. It has a lot of good stuff in it, and excellent speakers, very good clips, and playful (rather successfully, surprisingly often) presenters. My favourite bit? Neil DeGrasse Tyson being interviewed about our place in the universe. If you’re not an expert on the anatomy of the idea, please have a listen, since this is one of the best (and quite funny) layperson’s quick descriptions I’ve heard on the subject.

Tim Ferris (on the unlikelihood or likelihood of travelling vast distances for expeditions in space) and Brian Greene (on the geometry of our universe – another good layperson’s level chat) are also in this segment, just before. Direct mp3 file link to that particular piece here.

-cvj Click to continue reading this post

Some Observations at Griffith Observatory

So I must apologize. I went to the preview of the Griffith Observatory so long ago now and did promise to blog about it with more than just one nice picture, but it did not happen. Partly because I had to go back across the Atlantic to do some work, and then got ill over the weekend I was planning to do it, and then…

Griffith Observatory

Anyway, here are some of my thoughts. First note that my two week delay means that this is no longer a scoop, since even the LA Times had a spread on the whole thing on Thursday. A rather nice one as well. I urge you to consult it for a lovely pull-out graphic of the whole site. There is also a special website with picture tours, nifty 360 degree interactive shots of the spaces, and other information. The Griffith opened yesterday.

What they’ve done over the last four or five years is simply shut down the entire building and rethink and redo a great deal of it. How to preserve the lovely 70 year old landmark, while making it even better? Simple question – simple answer: Get $93 million for your project (I find this number, the earth-sun distance in miles, suspicious), and then go underneath the existing building and hollow out about the same amount of space that is has, but underground. Fill it with lots of goodies. And I mean lots and lots. What goodies? We’ll see. […] Click to continue reading this post

Fashionably Deconstructed

Spotted in the windows of a Department store (Hermes?) in Dublin (click for larger):

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They are trying to invoke a car that has been taken apart and draped with hermes 2 splendid clothing to form the display. In the picture below (click for larger), the second window’s oil can, in the carefully chosen-to-match colour, is a […] Click to continue reading this post

Memories, Physics, and Celebration

It’s a pleasantly foggy morning here on the USC campus. It is 7:00am now (at least at start of writing), and it will all burn off in a few hours, I imagine, to reveal the sunny sky waiting for us. But right now it reminds me of the Cambridge morning of a couple of weeks ago. A foggy Saturday morning in fact. I took that photo of the spider web I used on Halloween with that mist in the background.

That Saturday of celebration of Andrew’s work (The Andrew Chamblin Memorial Conference) at Cambridge was a remarkable experience. I was exhausted through a good deal of it, since I had eight hour jetlag, but I’m so glad I went, and that I could contribute a talk. I met many old friends and colleagues, drawn mostly from the UK and European side of Andrew’s collection of friends, collaborators, and admirers in the field.

andrew chamblin memorial conferenceThere were talks by former collaborators of Andrew’s: Gary Gibbons, myself, Roberto Emparan, Robert Caldwell, Raphael Bousso, and Stephen Hawking (who also guided some of Andrew’s thesis work). Gary, in “Discrete Symmetries and Gravity”, talked about Andrew’s early Oxford and Cambridge work on various discrete symmetries in physics, particularly those of a geometrical origin. He’d played with various ideas in this context, including some applications to problems in […] Click to continue reading this post