Slashdot Mirror
First Definitive Higgs Result In 7 Years
PhysicsDavid writes "In a suite of new results about the Higgs boson, Fermilab presents the first new definitive evidence on the (lack of) existence of the Higgs boson since the Large Electron Positron collider shut down in 2000. Fermilab hasn't found the Higgs, but can rule out a certain range of masses for the particle that is believed to create mass for all the other particles of nature. Other Higgs news suggests a new likeliest mass range of 115 to 135 GeV for the Higgs. These results were among those presented at the ICHEP 2008 conference currently wrapping up in Philadelphia."
Like many others, I thought this meant the LHC had finally come online. It's just fermilab enjoying its last two days of relevancy ^_^
I am one of many. My idea is not unique, nor do I expect my voice alone to sway you. I speak in a chorus of opinion.
Knowing the mass of the higgs is important because it tells us which of our theories is on the right track. For example, a very large higgs would rule out huge branches of string theory, almost killing it. Not finding it at all would rule super symmetry would destroy the standard model, with nothing left to stand it in place.
The 'worst' case is that we find the higgs exactly where we expect it to be, confirming what we pretty much knew already, without adding any new real information.
Don't joke about that, I'm sure I read about a paper last year which predicted a minimum Higgs mass just outside of the LHC's range. It must keep those involved awake at night.
No kidding!!! What do you say at this point?
Would someone explain why mass is expressed in GeV? GeV sounds like a measure of electrical field strength.
In case anyone else is a confused about this as I was, apparently "by mass-energy equivalence, the electron volt is also a unit of mass. It is common in particle physics, where mass and energy are often interchanged, to use eV/c, or more commonly simply eV with c set to 1, as a unit of mass." And "1 GeV = 1.783×1027 kg." At least according to:
http://en.wikipedia.org/wiki/Electron_volt
"This thing does science so hard, you say, 'I've never seen that much science.'" -Sam
Not to diminish the importance of the work done at Fermilab, but the headline is very misleading.
Okay, I only have a 4 year degree in Physics so maybe someone can help me out on this. If this particle gives the property of mass then shouldn't it have a mass less than that of the lightest particles? According to a quick Google calculation this thing out-masses an electron by 5 orders of magnitude.
WTF?
Isn't it 2008 right now?
Yeah, but there are those pesky things called months.
Cryptozoologists have narrowed down the possible habitat range of the Abominable Snowman. Spokesman for the research team, Dr. Justin Wanker, said "We've got him pinned down now!"
Only his tendency toward a dazed stupor prevented him from screaming aloud.
The SSC in Texas was 40 TeV, and the LHC at CERN will be 14 TeV when fully operational. They're about to turn on now, but will make their first run at the lower 10 TeV. Fermilab runs at 2 TeV.
Yes, we would have had the answers to all these questions and more 10 years ago, if the SSC hadn't been scrapped.
<soapbox>
The US is at a significant disadvantage when it comes to "big science". Every year, every project must come back to congress and beg for funding, justify their existence, rather than spend that time doing science. As a consequence, funding in the US is extremely volatile. Look at the budget crisis of DOE in December, the zeroing of the ITER budget, and the canceling of the SSC in 1993 for a few examples. Big science is worthwhile. We should figure out how to give scientists some measure of job security, so they can concentrate on science. This is a miniscule portion of the budget.
</soapbox>
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
The SSC being shut down still makes me mad. The politicians still consider it a win though, since they shut down that "wasteful government racetrack for microscopic particles".
I read the internet for the articles.
The short answer is this: according to the standard model, there are several different energy ranges that the higgs boson could possibly be in. I can't remember what the numbers are off hand, but I know that the Higg's boson energy is either small (from what they're trying to prove here), large - what LHC is trying to get at, and the holy-mother-of-god high. The latter would take an accelerator about the size of the Milky Way Galaxy to get to those energies using the same methods that we use in modern accelerators. Like the first post said; nothing to see here, move along.
Not finding it at all would rule super symmetry would destroy the standard model
It would destroy the SM but would not necessarily rule out Supersymmetry. Existing SUSY models only require two Higgs doublets because we think the Higgs is the way the particles gain their masses and given that assumption SUSY will need at least two of them (though more are not excluded). If the Higgs mechanism is not the way the universe works then who says the new mechanism, whatever it is, will preclude the existence of SUSY? The main argument for SUSY (to explain a light Higgs) may be gone but there are others: Dark Matter, unification of forces etc.
Actually is it not. Mass is correctly expressed in units of GeV/c^2. Einstein showed that energy and mass are equivalent with his famous E=mc^2 relationship. Hence mass, m=E/c^2. Thus we can use units of energy/c^2 to measure mass. This is particularly useful in fields like particle physics because we often convert mass into energy, or vice versa, and so it is useful to know how much energy it takes to create a particle (or is released in a particle decay).
Using units of 'GeV' for mass is actually very sloppy and technically wrong because energy and mass do not have the same dimensions and so cannot have the same physical units. The usual excuse is the use of natural units where c=1. However that '1' has dimensions associated with it and so to ensure that those dimensions are preserved you need to include it in the units. Hence mass is actually measured in 'GeV/c2' and not 'GeV'. Similarly momentum can me measured in units of 'GeV/c'.
At the Tevatron, the backgrounds to two bottom quarks isnt soo bad and the experimenters are all very experienced at tagging b quarks using their detectors.
Actually the background for b quarks at the Tevatron is ENORMOUS. b-quarks are produced by the strong interaction at rates far higher than they are produced from any possible Higgs decay. Identifying them is only half the problem: determining what produced them is the other half! The only way that we can see anything is via associated production of a Higgs and a W or Z boson (which are a lot easier to spot). This is a far rarer process than simple Higgs production.
At the LHC you might as well give up so you have to go through the very rare vector boson fusion channel using a top quark loop to get two photons which itself has a bit of nasty background.
You are actually a little out of date here. While the vector boson fusion channel is still used the decay is actually Higgs to two taus or VBF Higgs production with the two associated quarks being top quarks. At least in ATLAS we think that both of these channels will have a higher significance than the photon channel which was the original choice for a low mass Higgs.
Can someone explain to me why we need something to give mass to something? Can't it just be that matter warps space-time? Since Mass and Energy are equivalent, why can't it just be that energy/mass warps space-time, and that mass is simply the effect we observe in the hree dimensional universe of this warping?
Occam's Razor says the whole concept of the Higgs Boson and the Higgs Field are wrong, much like String Theory.
Edward@Tomato - /home/Edward/ man woman
man: no entry for woman in the manual.
"Qua!?"
<soapbox> The US is at a significant disadvantage when it comes to "big science". Every year, every project must come back to congress and beg for funding, justify their existence, rather than spend that time doing science. As a consequence, funding in the US is extremely volatile. Look at the budget crisis of DOE in December, the zeroing of the ITER budget, and the canceling of the SSC in 1993 for a few examples. Big science is worthwhile. We should figure out how to give scientists some measure of job security, so they can concentrate on science. This is a miniscule portion of the budget. </soapbox>
I fear that as long as the creationists are in power in the US science will always have low priority. The last thing they want is that scientists discover how the universe was created as this would be a huge blow to the credibility of their god. Very sad indeed.
While religious nuts are an easy scapegoat, that's not the problem. As I understand it, it comes down to the fact that no congress can bind any future congress. So no congress can set budget policy in any future year. They can make recommendations (and do), but this isn't guaranteed.
I don't think this problem is insurmountable. I would think that the creation of a certain kind of "scientific trust fund" could enable the use of a pot of money over a long time span.
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
The US would rather fight some bullshit war on "Terror" or "Drugs" (how do you win against inanimate objects they never say), then actually put the money to good use such as Science or helping to have no homeless.
no congress can bind any future congress. So no congress can set budget policy in any future year. They can make recommendations (and do), but this isn't guaranteed.
And yet, America is the only country I see consistently restricting themselves like this. Certainly in Britain, one pariliament can't set budget policy for the next, but projects don't have to rejustify funding every year and cancellations of large science projects are rare.
And when it comes to your Presidents... Doesn't Bush seem to be doing a good job of binding spending for the next president? If there is no money...
todo - The developer's equivalent of confession: "Forgive me Father, for I have sinned..."
There's a great analogy for this which will probably help, http://www.hep.ucl.ac.uk/~djm/higgsa.html .
IIRC this was the result of a competition by Physics World (the magazine of the Inst. of Phys.).
A great philosopher may or may not have described that best:
There, I may or may not have fixed that for you.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
The link s/he posted has extremely nice analogy. Unfortunately, I have no idea if it is a correct analogy but it is definitely easy to understand and makes sense too. Maybe someone who understands the math behind Higg's mechanism can comment on the aptness of the analogy.
Actually the worst case would be all Higgs bosons sucked into micro black holes created at energies just below the Higgs. Have you read the leading paper on LHCFacts.org?
> Cosmologists are willing to dismiss observations because they don't fit with theory?
Do cell phones cause cancer? Probably not, in spite of people saying they have data to show it. Extraordinary claims require extraordinary data, and the data presented so far is nothing close to extraordinary.
Explain how this is any different.
Maury
Every $ spent on the SSC was a $ that could not be spent on other science, like finding out if dinosaurs had colors, for example. The problem was that four projects, the SSC, the ISS, ITER, and the Human Genome Project were contemplated at the same time and would have sucked up all of the funding that the US typically has on a year to year basis. IMHO, they canned the wrong program. The ISS is the one that should have been given the axe. But one or more of them had to go in order to keep funding thousands of small science research projects that are equally worthy of interest. Physicists are not entitled to every damn dollar of science funding the US has. Didn't your mothers try to teach you to share back in kindergarten?
FreeSpeech.org
Lousy Smarch weather.
haha. LHC is a global effort. In fact, all large future colliders will be a global effort. Cost, complexity, and knowledge base requires it.
It's location won't be relevant.
This is a good thing.
And Fermilab isn't desperate. People are creating a false dichotomy. People like you.
The Kruger Dunning explains most post on
It has nothing to do with sharing. The US committed to a project, dumped several billion into it, and then cancelled it. That's just stupid. A better solution would have been to extend the time frame of one or more projects, so that all projects could be accomplished, and we don't lose all that expertise and already-spent dollars.
And for the record, the ISS cost more than a factor of 10 more than initially estimated. The cost overruns of the SSC (at the time) were miniscule in comparison.
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
It had everything to do with sharing. Please read the debates that were going on in the early 1990s between particle physicists and others who stood to lose funding. Yes, it would have been nice if the $2 billion had not been spent, but go read up on the concept of sunk cost to understand why that $2 billion already spent was not relevant when deciding whether to spend still more.
But critics say big projects drain funds from small-scale research vital to the creation of new products and jobs and often to the advance of science itself.
"Big science has gone berserk," said Dr. Rustum Roy, professor of materials science at Pennsylvania State University, who is an adviser to the House Committee on Science. "Good minds and a lot of money are going into areas that are not relevant to American competitiveness, American technological health, or even the balanced development of American science."
Dr. George F. Chapline, a physicist at the Lawrence Livermore National Laboratory in California, said the trend bodes ill for the nation. "It is very questionable whether these projects will contribute much to stopping America's industrial decline, and may even exacerbate it," he said.
Moreover, the big instruments can take so long to plan and build, sometimes a decade or more, that they are sometimes seen as obsolete when switched on because science now moves so fast. Perhaps most troubling, this same lag is seen as causing bright graduate students to abandon some fields now dominated by giant instruments as they search for timely projects on which to base their Ph.D. research.
Disclaimer: My father got his start in accelerator physics where he helped design this so our family has some experience with unexpected funding cutbacks.
FreeSpeech.org