Further Information on Dark Energy

So the press conference is over. I did not listen to it, but the gist of it, from the press release, seems to be that they’ve observed several more supernovae to pin down even more accurately what the universe’s expansion rate was at very early times (up to nine or ten billion years ago). Image below from their site:

[image]

From the site we learn (for background): Click to continue reading this post

Less In The Dark Than Before?

From NASA, tomorrow, at 1:00pm EST: An announcement about Dark Energy. If the pattern of last time is to be followed, there must be new evidence from the space telescope team (represented by Riess and Livio at the press conference) in favour of one interpretation or another. Since they are saying that they will “announce the discovery that dark energy has been an ever-present constituent of space for most of the universe’s history”, I imagine that means that there is stronger evidence than before for Dark Energy being a cosmological constant. […] 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

New Colleagues

Ah! The joy of new colleagues! I have somehow forgotten to tell you one piece of the great news that we had here at USC Physics and Astronomy recently. We got three new faculty, and one of them is here in action (I’ll tell you about the others later), telling us about the physics behind the 2006 Physics Nobel Prize. This is Cosmologist/Astrophysicist Elena Pierpaoli:

[image]

She’s one of those people who works closely on (among other things) the data from […] Click to continue reading this post

Physics Nobel Prize 2006

COBE is the experiment that really blazed the trail for all the wonderful physics that was to come from WMAP, and various other experiments such as Boomerang. And Planck is about to fly as well, giving even more precise information about our universe.

I was an undergraduate when this was announced. [Update: Oops…not quite: I had just started graduate school. Thanks Chad!] It was a wonderful feeling that all of us students had, partly gleaned from the feelings of our lecturers, I suspect. The thing that struck us as most appealing (I think) was the idea that the black body radiation spectrum (click on the image on the right for larger) that we’d been learning about in the abstract, during lectures, was sort of “out there”, writ large…. as large as can be in fact, on the whole universe! It’s always good to learn that physics -or any field- is still alive, especially when you’re still on the cusp of making a career in it. […] Click to continue reading this post

Explaining Cosmic Rays

Well, before disappearing into a long session of thinking about some funny behaviour my strings are up to (more later) I’d like to do a quick report on the departmental colloquium that I went to just now. We had Gary Zank, the Director of the Institute for Geophysics and Planetary Physics of the UC system (he’s based out of UCR) give us a talk entitled: “Particle Acceleration in Cosmic Plasmas”, and it was quite fascinating (and very well presented).

It is all about the physics of cosmic rays […] Click to continue reading this post