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Maxx
11-15-2010, 09:16 PM
http://www.science20.com/quantum_diaries_survivor/first_zz_event_cms

Bartholomew
11-15-2010, 10:30 PM
http://www.science20.com/quantum_diaries_survivor/first_zz_event_cms

Translation please?

dclary
11-15-2010, 10:38 PM
It's like physics nerds getting a perfect 100 when rolling for epic loot after a weekend-long raid.

Torgo
11-15-2010, 10:41 PM
Translation please?

Over at the Large Hadron Collider they may have seen evidence of the decay of the Higgs boson. It could be something else, but it could be the Higgs.

This would be cool because the Higgs is the last remaining elementary particle that we are expecting to exist but haven't detected yet. It's like the last sticker in the Standard model's Panini album.

Torgo
11-15-2010, 10:42 PM
It's like physics nerds getting a perfect 100 when rolling for epic loot after a weekend-long raid.

This is a much better translation.

Maxx
11-16-2010, 12:03 AM
This is a much better translation.

This would be more like "Loot in a reasonable range" (GeV 140-190)
and no 4th generation of matter and minimal supersymmetry and maybe no classic SUSY.

So, it would imply a more orderly cosmos and a less wild and wooly range of supersymmetric fields.

Julie Worth
11-16-2010, 12:33 AM
Bet Peter Higgs was sweating bullets.

FOTSGreg
11-16-2010, 04:04 AM
Um, okay...

If this occurred, what's it say about the possibility of gravitons, dark matter, the future of the universe, and FTL?

What about dark energy, white holes, string theory, and the existence of other dimensions?

Lhun
11-16-2010, 04:52 AM
If this occurred, what's it say about the possibility of gravitons, dark matter, the future of the universe, and FTL?Afaik, nothing. Different issue. Not to mention that those 4 issues are also not very related.

What about dark energy,Nothing. It's unlikely there'll actually be any experiments about dark matter or energy until we have a better understanding of both. "Unknown stuff we observe in the universe" doesn't exactly lend itself for easy experimental examination.

white holes,As fictional as Klingons. That is, general relativity does allow for the theoretical existence of them (as does biology for Klingons) but there's no observed data to suggest there are any.

string theory, and the existence of other dimensions?Afaia, still no-one has come up with an experiment that could be used for confirmation or falsification of string theory.

Maxx
11-16-2010, 04:47 PM
Afaik, nothing. Different issue. Not to mention that those 4 issues are also not very related.
Nothing. It's unlikely there'll actually be any experiments about dark matter or energy until we have a better understanding of both. "Unknown stuff we observe in the universe" doesn't exactly lend itself for easy experimental examination.
As fictional as Klingons. That is, general relativity does allow for the theoretical existence of them (as does biology for Klingons) but there's no observed data to suggest there are any.
Afaia, still no-one has come up with an experiment that could be used for confirmation or falsification of string theory.

The Higgs is supposed to provide particles with their mass so its related to all of this. Since it effectively links the background vaccuum with vector bosons it could be part of the explanation of Dark Energy.
I've also seen a paper recently where a String Theoretic interpretation of the Higgs explains why there's a predominance of matter over anti-matter. The Higgs -- especially in this relatively low energy range (around 150 GeV plus or minus 30) -- would reduce the range of possible theoretically relevent models a lot. A lot of string theories might be ruled out and a lot of SUSY might have to go. An experiment where the Higgs interacts with antimatter might rule out a lot of string theories.

Lhun
11-16-2010, 10:11 PM
Well, yes, once experimenting with the Higgs boson becomes possible, there is quite a lot that could be learned. But so far it's just about detecting one. Since the existence of the higgs boson is predicted by the standard model, actual confirmation is not going to produce a lot of new knowledge, it just confirms the accuracy of the model (further).

Maxx
11-16-2010, 10:38 PM
Well, yes, once experimenting with the Higgs boson becomes possible, there is quite a lot that could be learned. But so far it's just about detecting one. Since the existence of the higgs boson is predicted by the standard model, actual confirmation is not going to produce a lot of new knowledge, it just confirms the accuracy of the model (further).

The actual structure (eg. one of them or 5 of them) and energy (eg if this one is at 201 GeV and it is not one of 5) of the Higgs could rule out SUSY and lots of string theories. The Standard Model has had lots of optional attachments built for it since it topped out at the Top Quark in 1994.

AND a Higgs in the current range would exclude a 4th generation of matter (top quark being the top of the 3rd generation). IIRC right around 200 GeV would be ambiguous.

So its not just detecting it. It's getting its size (GeV) and structure (one or more?). That will have a significant impact on all the theories that have grown wild since 1994.

dclary
11-17-2010, 03:07 AM
You have managed to say what it means without saying what it means at all.

Let's rephrase the question:

Why would anyone not with a PhD in physics care? What practical real-world application does observing a Higgs boson event benefit?

PsychicToaster
11-17-2010, 06:36 AM
We won't know what consequences a Theory of Everything that is consistent with all observed phenomena will have until we actually have a valid ToE.

It could be as simple as a bunch of guys with multiple PhD's each sitting around and going, "Oh, ok. That's it then." Or it could provide evidence that all our assumptions about how the universe works are wrong, or it could provide evidence that all our assumptions about how the universe works are right. It could be as radically transformative as providing a theoretical method of manipulating gravity at human scales using high energy fields. Far fetched, but not strictly impossible until we learn just where gravitation meets the other fundamental forces (and still pretty far fetched even if/when we do).

Maxx
11-17-2010, 04:44 PM
You have managed to say what it means without saying what it means at all.

Let's rephrase the question:

Why would anyone not with a PhD in physics care? What practical real-world application does observing a Higgs boson event benefit?

It would confirm (or not) the entire standard model, which covers what exactly all the stuff that you see everywhere all the time actually is.

In terms of cooking, it would be equivalent to letting you know whether you were always using too much salt or not.

In terms of driving, it would let you know whether your oil pressure gauge was measuring the oil pressure.

JimmyB27
11-17-2010, 05:22 PM
Why would anyone not with a PhD in physics care?
I don't have a PhD in anything, and I think it's great, because science is cool!


What practical real-world application does observing a Higgs boson event benefit?
Science is often done without any explicit, practical end result in mind. But it often yields such applications that no-one had really thought of.

Lhun
11-17-2010, 06:32 PM
So its not just detecting it. It's getting its size (GeV) and structure (one or more?). That will have a significant impact on all the theories that have grown wild since 1994.My point was that the current experiments at the LHC aren't so much about getting new information as about confirming which of several extant theories are correct. Unless the result are completely out of the expected ranges, all the implications have already been thought through theoretically.

Raindrop
11-17-2010, 07:03 PM
Over at the Large Hadron Collider they may have seen evidence of the decay of the Higgs boson.
Okay. I'm bad at physics. No, scratch that. I'm bad, period. Here's how I read it:
Over at the Large Hardon Collider they may have seen evidence of the decay of the Higgs bossom.

*bow head in shame*

Raindrop
11-17-2010, 07:05 PM
It would confirm (or not) the entire standard model, which covers what exactly all the stuff that you see everywhere all the time actually is.

In terms of cooking, it would be equivalent to letting you know whether you were always using too much salt or not.

In terms of driving, it would let you know whether your oil pressure gauge was measuring the oil pressure.
Ah, okay. That would be quite epic, indeed.

Maxx
11-17-2010, 07:40 PM
My point was that the current experiments at the LHC aren't so much about getting new information as about confirming which of several extant theories are correct. Unless the result are completely out of the expected ranges, all the implications have already been thought through theoretically.

It's true that in some ways the build up for the Higgs makes it sound less climatic than say, the observation of the cosmic microwave background in 1965. One difference would be that cosmology wasn't as much a matter of engineering in those days and no one had paid any attention to the predictions of Gamov and company in about 1950 that there would be such an indication of a Big Bang. On the other hand, not finding any Higgs particles in the range under 200 GeV would be a very strange thing. In fact if the current event cited in this thread is a Higgs, it is already (at 201 GeV) in a very surprising place in terms of the ranges that are related to various theories. For example it looks like Minimal Supersymmetry (which sounds "just right" right?) is holding up better than plain old vanilla SM (standard model, no supersymmetry). So It looks like MSSM is better supported if I'm reading the following properly:

http://unizh.web.cern.ch/unizh/Publications/Articles/Higgs.pdf

In which case the neutralino might be a major part of dark matter.

RemusShepherd
11-17-2010, 08:03 PM
Let's rephrase the question:

Why would anyone not with a PhD in physics care? What practical real-world application does observing a Higgs boson event benefit?

Observing and measuring the mass of the Higgs boson will tell us which of several competing unified theories is correct.

Since we already have theories to tie together most of the physical forces, the main practical, real-world application that could come out of a validated unified theory is Antigravity. Also, control of radioactive decay and probably a million other exotic technologies, but antigravity is the sexiest one I can give you.

That's not to say that any of those things are possible and will someday exist. We don't know for sure. But we know that they are completely impossible until we have a unified theory, and we can't have one of those until we observe the Higgs.

Maxx
11-18-2010, 12:36 AM
Okay. I'm bad at physics. No, scratch that. I'm bad, period. Here's how I read it:


More on Higgs:

http://io9.com/5690248/whats-the-matter-with-the-higgs-boson?skyline=true&s=i

lpetrich
11-22-2010, 07:57 AM
http://www.science20.com/quantum_diaries_survivor/first_zz_event_cms
The First ZZ Event In CMS!! (http://www.science20.com/quantum_diaries_survivor/first_zz_event_cms)

It was a 4-muon event, 2 energetic negative muons and 2 energetic positive ones coming out of an event - so energetic that they were barely deflected by the CMS detector's magnets.

Pairing up the positive and negative muons gives one set with an invariant mass of 92.15 GeV, and one with an invariant mass of 92.24 GeV, in close agreement with the Z mass measured elsewhere. There are no jets of hadrons, a sign of very energetic quarks or gluons, and the combined mass of the two is 201 GeV.

This is about where a Higgs particle may be, but it's only one event, and it will be necessary to observe several more to get a better picture. That event could be the result of a more "normal" electroweak process, for instance. If one observes several events, then one may be able to tell if they tend to cluster around certain masses. Furthermore, the relative directions of the outgoing particles may provide additional clues as to the nature of the particles involved, like what spins they have. Z's have spin 1, and Higgses ought to have spin 0.

That technique was used to find what spin a gluon has -- 1 (paper: Measurements of Gluon Spin-Sensitive Quantities at the Z0 Resonance (http://www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-5975.pdf))

-

As to possible Higgs particles, the plain Standard Model predicts a single neutral one and no charged ones, while the Minimal Supersymmetric Standard Model predicts 3 neutral ones and 1 charged one with charges +1 and -1. So even if this recent event is due to a Higgs particle, it can't decide between the SM and the MSSM --there are some fudge factors that can be adjusted to get a Higgs particle with the "right" mass.

Maxx
11-22-2010, 05:10 PM
As to possible Higgs particles, the plain Standard Model predicts a single neutral one and no charged ones, while the Minimal Supersymmetric Standard Model predicts 3 neutral ones and 1 charged one with charges +1 and -1. So even if this recent event is due to a Higgs particle, it can't decide between the SM and the MSSM --there are some fudge factors that can be adjusted to get a Higgs particle with the "right" mass.

201 GeV might be a bit high for the Standard Model. Wikipedia says:

As of August 2009, the Standard Model Higgs boson is excluded by electroweak measurements above 186 GeV at 95% CL. However, it should be noted that these indirect constraints make the assumption that the Standard Model is correct. One may still discover a Higgs boson above 186 GeV if it is accompanied by other particles between Standard Model and GUT scales.

FOTSGreg
11-23-2010, 08:55 AM
<BOOM!>

<woosh>

Damn those things flying so far and fast over my head whatever they are...

:)

Smiling Ted
11-25-2010, 01:13 AM
I get the sense that even if choosing the correct TOE theoretically allowed us to do all that neat "control gravity/control radio-decay" stuff, it would be at astoundingly energy levels. Like, Big Bang levels. No? Yes? No way to know?

Maxx
11-26-2010, 10:23 PM
I get the sense that even if choosing the correct TOE theoretically allowed us to do all that neat "control gravity/control radio-decay" stuff, it would be at astoundingly energy levels. Like, Big Bang levels. No? Yes? No way to know?

I have no idea, but when you think about the unexpected findings of detector experiments (eg, the neutrinos from
supernova 1987a

http://adsabs.harvard.edu/full/1988SvAL...14...41A ),

it seems like working on defining the Higgs (if there is one) is bound to
have many as-yet-unimaginable pay-offs.

lpetrich
12-10-2010, 04:40 PM
201 GeV might be a bit high for the Standard Model. Wikipedia says:

As of August 2009, the Standard Model Higgs boson is excluded by electroweak measurements above 186 GeV at 95% CL. However, it should be noted that these indirect constraints make the assumption that the Standard Model is correct. One may still discover a Higgs boson above 186 GeV if it is accompanied by other particles between Standard Model and GUT scales.
That's the plain Standard Model. The Minimal Supersymmetric Standard Model (MSSM) would allow such a Higgs -- it would be one of the heavier MSSM ones.

The plain SM predicts only one Higgs, a neutral one.

The MSSM predicts 5 Higgs states: 3 neutral ones, and a charged one with +1 and -1 versions.