astro
catdynamics | August 9, 2012The LHC Shows the Way workshop is about to end, and the slow live blog limps along with a presentation on the composite Higgs.
A model for having a light (~ 100 GeV ) scalar, is to have a composite Higgs instead of the alternative of either a true supersymmetric model or a light dilaton scalar.
As with such models in general, they violate unitarity if extrapolated to higher energies, so force a new energy scale, at, say, few TeV - like another particle there (cf old effective weak interaction theory).
Yes, if you work it out in detail, the effective coupling runsaway and you need to truncate…
catdynamics | August 8, 2012The Sloan Digital Sky Survey just released their largest 3-D data set, positions and redshifts, as part of their 9th data release.
Here is the fly through.
Awesome, eh?
catdynamics | August 6, 2012This spring, the Hubble outreach office started a Hubble Treasure Hunt
The challenge was to browse through the Hubble raw data archives, and look for undiscovered images, ones that had not been published and were interesting or beautiful.
There are a lot of Hubble images.
The finalists for the contest have now been announced, in two different categories: one for unprocessed images; the other for processed images.
The decision on the winners, will be done by public vote, and the selection of finalist images is up on the web and open for voting:
unprocessed images are here
processed images…
catdynamics | August 2, 2012In which we ask, what would you do if you could change your own personal history?
A Kind of Magic! - No, that is not a non-Higgs boson, it is the Astronomy Magazine competition to win a signed copy of Brian May's PhD thesis in astronomy.
"To enter the contest, submit a short essay (200 to 500 words) that describes what you would do — what would your subject be and why? — if you could magically go back to school and earn a doctoral degree in astronomy.
How would you change the astronomy world? What research subject would entice you? Planetary science? Cosmology? Galaxy investigations? And what…
catdynamics | August 2, 2012Back at the LHC Shows the Way workshop and slow live blogging of the discussion, with random asides for other stuff...
Astronomy Magazine has a contest - win Brian May's PhD thesis! - now separate post with added bonus question
Today:
fake Higgs - are there some new bosons which are not Higgs, but which look like Higgs. Specifically looking at other scalar or pseudoscalars, or the possibility of spin-2 tensor particles.
Aside: cool 2D fluid flow web site - GPU powered 512k sim run live through WebGL - hypnotic turbulence to crash your browser
Look for general models where some particle…
catdynamics | July 31, 2012Continuing lazy live blog of the LHC Shows the Way workshop, with random interludes of alternative considerations, including the more esoteric aspects of German finance...
Patio session (informal presentation of in-progress results on blackboard, outside) - didn't catch speaker's name, got here a couple of minutes late.
Being reminded that Higgs is not the only scalar that may exist out there - could the LHC 125 GeV bump be a dilaton?
Paper by Csaki and collaborators coming out in August on arXiv.
Aside: the proliferation of chargeless scalars in quantum field theories has always bothered me…
catdynamics | July 26, 2012LHC Shows the Way workshop: general colloquium reviewing the LHC and the Higgs discovery.
Kyle Cramner from NYU: "We discovered the goddamned particle"
More slow live blog.
Cute opening video of LHC construction.
Factoid: kinetic energy of LHC beam is about that of a jumbo jet at cruise speed
Starting point: Standard Model is ridiculously successful, at the part per million quantitative level.
In the regime in which it is valid.
Add Higgs and you don't just get mass, you get coupling to fermion decay is proportional to the Higgs induced mass of the fermion.
Can calculate Higgs boson…
catdynamics | July 26, 2012The LHC Shows the Way workshop rolls on, looking at the implications of the Higgs at 125-126 GeV for supersymmetry.
I live blog, slowly.
Where are the sparticles.
Coloured supersymmetric partners, the quark and gluon supersymmetric partners, must be massive - greater than ~ 1,000 GeV
in some natural implementation of supersymmetry, natch, clever theorists can of course think of increasingly contrived ways to get around most any limit, at the expense of fewer and fewer people believing them.
Minimal supersymmetric extensions to the standard model, with the Higgs mass assumed to be 126 GeV and…
catdynamics | July 24, 2012For reasons too complicated to explain, I am at The LHC Show the Way workshop at the Aspen Center for Physics.
This is a three week workshop on the latest results from the LHC, to be followed by a four week workshop on new physics from the LHC and possible connections to dark matter.
The kickoff presentation is on the current status of the experimental results. Relayed from the ICHEP meeting.
Just for fun I'll do some liveblogging from the somewhat outside perspective of an astrophysicist.
The current run at the LHC will be extended to Dec 17, couple months beyond planned before going into a…
catdynamics | July 10, 2012Massive Reductions in Force announced at NRAO with additional major cutback at operations and facilities.
Forwarded without comment:
"Dear Colleagues,
This message is to inform you of actions NRAO is implementing to address an expected (non-ALMA) FY 2013 budget deficit of approximately $3M for our U.S.-based facilities: the Very Large Array, Very Long Baseline Array, and Green Bank Telescope.
After careful consideration of user community and Observatory priorities, and a comprehensive analysis of our options, we have been forced to conclude that a significant reduction-in-force and a…
catdynamics | July 9, 2012time for all new linkedy links here at the new digs
Quantum Frontiers - a new blog from the Institute for Quantum Information and Matter, with kickoff by John Preskill hisself.
Question of the day: explain quantum mechanics in five words
My attempt: Probability Amplitudes, Observables don't Commute
Good to know John still does khakis and chalk, but we gots to know: does he still have the diet pepsi?
Took me years to break the habit... not that I was overly impressionable as a tender young grad turkey taking QFT or anything.
Subtleties of the Crappy Job Market - for Scientists, that is.…
catdynamics | July 4, 2012In the beginning there was light.
Sort of.
When energies were high enough, particles were effectively massless and the universe was a nice seething mess of particle/anti-particle creation and annihilation.
As the universe cools, a symmtery, the Electroweak symmetry breaks, a field condenses out, and interesting stuff starts happening.
Hence we get chemistry, and the autocatalytic evolving goo that reaches out and ties to puzzle out where it all came from.
In the Standard Model of Particle Physics, the rest mass of the spectrum of normal matter particles is dynamically generated. The mass we…
catdynamics | June 24, 2012Why do we need to spend any more effort on extra-solar planets?
We found some, they're there. Lumps of rocks, gasballs. We're done, right?
This, loosely paraphrased, was a serious question I got last week.
The context was a question of why I was spending serious effort on exoplanet research, rather than focusing exclusively on other subfields.
I've heard similar comments from physicists, some particle physicists are notoriously focused in their consideration of what counts as "real physics", but this came from an astronomer; and one that I know does stars, inside the galaxy, sometimes, not…
catdynamics | June 24, 2012"Name one thing robots can't do in space that humans can!" was the challenge from a speaker at a meeting I attended many years ago.
"Have babies!" was the loud and prompt reply from a grad student friend of mine at the back, thereby winning the argument to great applause.
It is important to remember that while science and discovery is important, it is not the ontological basis for space exploration.
Space is, ultimately, about existential motivations. The science helps drive the motivation, and provides the information that enables space exploration, but is in many important ways not the…
catdynamics | June 23, 2012SETIcon feels like a curious mix of an AAS annual meeting and a science fiction WorldCon.
Unfortunately, this extends to the concept of the parallel session.
So, it is necessary to pick and choose.
So, "Asteroids: Junkpiles or Resources?" - Yes.
"Hubble 3D" - I really want to see Frank Summers' rendition, but I'll get another chance.
And, while I do want to know "When I can buy a ticket to the Moon", I got the rah-rah spiel
on the impressive progress in commercial space already.
Hence the panel on: "The Next Big Science Revolution" - I gots to know.
As apparently does everyone else. Another "…
catdynamics | June 22, 2012We know now that there are planets out there.
Lots and lots of planets.
We are still pinning down the exact incidence over all stellar populations, and we are barely at the point where we can directly confirm the presence of terrestrial planets, but if parameter space is smooth and the universe does not conspire against us, then terrestrial planets must be quite common.
10% incidence would not be a bad conservative guess, but I would not be surprised if the incidence is 30-50%.
We will know for sure soon.
We don't know how life starts.
We have some well founded suspicions, and every year the…
catdynamics | June 22, 2012The SETI Institute is sponsoring the Second Search for Extraterrestrial Intelligence Conference at the San Jose Santa Clara Convention Center this weekend.
The Conference is an unusual blend of hard science, science fiction and media: with Geoff Marcy, Alex Filippenko and Debra Fischer, among others, mixing in with NASA honchos, Silicon Valley enthusiasts and Bill Nye the Science Guy.
There are three days of talks, presentations and parallel sessions on topics ranging from "The Kepler Mission" to "Would Discovering ET Destroy Earth's Religions".
Saturday night Jill Tarter is being honoured…
esiegel | June 8, 2012"Building one space station for everyone was and is insane: we should have built a dozen." -Larry Niven
Here on the solid ground of the Earth, the Sun and Moon rise and set on a daily basis. During the hours where the Sun is invisible, blocked by the solid Earth, the stars twirl overhead in the great canopy of the night sky.
Image credit: Chris Luckhardt at flickr.
In the northern hemisphere, they appear to rotate around the North Star, while in the southern hemisphere, the stars appear to rotate about the South Celestial Pole. The longer you observe -- or for photography, the longer you…
catdynamics | June 7, 2012"Statistical thinking will one day be as necessary for efficient citizenship as the ability to read and write." H.G.Wells
Today! I swung by the penultimate session of the VIIIth Summer School in Statistics for Astronomers, just to catch a couple of old friends who were at the school, chat a bit at the coffee break, and get a quick refresher in clustering...
The school, being the 8th in a series, is offered by the Penn State Center for Astrostatistics, an NSF funded interdisciplinary center in, well, astronomy and statistics.
The school is very popular, and is aimed at graduate students in…
catdynamics | June 5, 2012there is a curious result in behavioural economics, which shows that paying people to do what they like to do, sometimes provides a disincentive for them to do it, and people correspondingly lower their effort to do the task.
The example I recently came across, from the 7 Rules of Behavioural Economics, or some such, was that if you pay people to have their friends for dinner, they entertain less.
But, enough about the decline of intradepartmental socialization...
The reason I thought of this, is that yesterday we congratulated a colleague on a nice result, and another colleague asked some…