On hadron colliders, dark matter and black holes

[maxsdaddy]

Date.. 12/13/11 msnbc releases anouncement that scientists have"cornered" the Higg's particle. Thats why I love the guild. Maps, art, and astrophysics. Perfect call torstan.

[Redrobes]

If the Higgs is supposed to account for mass and the theory says that the vacuum is chock full of Higgs particles that impede the movement of other particles to give them mass then the bit I cant understand is why its stated that the Higgs exists for about 10^-15 of a second or so. How is it that space is chock full of them when they decay so quickly ? If the LHC can only see the remnants of the decayed Higgs and the Higgs were all condensed out at nanoseconds after the big bang then why dont we have mass only nanosecs after the big bang then we all become mass-less after that point ? Is it that the vacuum spontaneously generates loads of Higgs particles then they decay back out of existence again on a continuous basis ?

Oh and did y'all catch this article from MIT where they make a camera take so many frames per second, it can actually film the photons traveling through space (not the one same photon of course, you have a pulsed stream of them). Its an awesome video:
http://web.mit.edu/newsoffice/2011/t...mera-1213.html

[torstan]

@Redrobes. Yep, I saw that. It's amazing!

For the Higgs - there's two things at work here. One is the Higgs field, which is the thing that gives particles mass. The other is the Higgs boson, which is basically an excitation of that field (more or less). The particle lasts for fractions of a second before decaying, but the field is stable and present everywhere.

The result of the announcement was that there's a 3.6 sigma signal of a Higgs boson in the ATLAS data and a 2.5 sigma signal in the CMS data. 3.6 sigma means that the data is 3.6 standard deviations away from what you'd find if there were no Higgs boson. Which really means there's a small fraction of a percentage chance that this is just a statistical fluke. You need a 5 sigma result (less than 1 in a million chance of a statistical fluke) before you can claim a discovery. More data will allow them to get to that threshold, and they should have enough data in the next year.

You might also note that each experiment has independent data, so they should be able to improve the confidence of the result by combining data? Well that's certainly true - they've done it once already with the summer data. That will certainly improve the result, but not to the point of crossing the 5 sigma threshold. Those results should hopefully be out for the Moriond conference in Feb/March. However we really want both the experiments to get the 5 sigma confidence level independently to make sure we've really found it. That should be late next year, with a progress report and new data by the summer conferences of 2012.

[torstan]

And a good breakdown on the CERN blog of why they're being so cautious: http://www.quantumdiaries.org/2011/1...sing-like-one/

[Bogie]

A neutrino walks into a bar, the bartender says "Hey! we don't serve your kind here!, The Neutrino says "It's OK, I'm just passing through."

[Map4fun]

I have a question. What happens to an object if it's exposed to the kind of cold (1.9 degrees above absolute zero) as mentioned about the magnets? I heard years ago that a chair exposed to near absolute zero simply crumbles... I'm a teacher to younger aged students who've asked me this question for the last few years - part of our unit of study for science is space and heat. I've simply told the students to come tell me about it if they get the experience. I'm hoping to know now whether or not things get weird when things get cold... really cold!

Thanks

PS. I just read in discover magazine that we've created anti-helium? In simple terms, what significance does creating anti-matter have?

[Map4fun]

Hilarious! love it. I've heard the one of the Mushroom that gets the same treatment. The mushroom simply replies: "Hey, I'm a "fungi".

[torstan]

I totally missed this comment I'm afraid. I'm not a condensed matter scientist so I can't really speak to what happens when a chair is cooled to that temperature.

However there are materials that do a lot of fun things when cooled to these sorts of temperatures. At low temperatures helium becomes superfluid, suddenly having zero viscosity. This means it can flow uphill, as long as it ends up lower at the end of it's journey. It's like a syphon, except that it doesn't need any outside force to get it flowing, it just starts flowing over obstacles on its own. Here's a nice short video showing some of that: http://www.youtube.com/watch?v=2Z6UJbwxBZI

In other news - it looks like we might get a Higgs discovery announcement tomorrow morning. All rumours and indications are that they've found something definitive. If so, that's the capstone on the great physics research project of the 20th century, and the first stepping stone in the next revolution in particle physics. I'll be up at 3am to see it.

[Ghostman]

So, word is out that the big-ass collider spotted some bosons, and it was party time in CERN

[torstan]

Certainly was We were up at 3am over here watching the live streaming event. Very impressive work all round. As a theorist I can only look on and be very impressed by what they've achieved! It's really amazing.