Higgs Particle. The Higgs Field In 1964 Peter Higgs (pictured at left) proposed that an invisible energy field (later named the Higgs Field) filled the universe immediately after the Big Bang. This field was analogous to an electric field, it filled the universe, was invisible, but did not carry any electric charge. The theory suggested that as the newborn universe expanded and cooled, the Higgs Energy Field developed. At that time, one billionth of a second after the Big Bang, massless particles that had been traveling at the speed of light in a super hot plasma type of soup, interacted with the "field" and became massive (took on mass). Some particles were affected by the field more than others. The more strongly particles interacted with the field, the more massive they became. One can think of the Higgs Field as a very thin invisible gas (sort of like air) that completely fills the universe.
The Higgs Boson Sometimes light behaves like a wave, i.e. sunshine, and sometimes like a particle. Top. The Higgs Boson and the Big Bang. Scientists from Europe’s CERN research center presented evidence on July 4, 2012, for a particle that is likely the Higgs boson, the last remaining elementary particle predicted by the Standard Model of particle physics.1 Does this discovery have relevance for the creation-evolution controversy?
Particles can generally be classified into two categories, according to the quantum mechanical rules that they obey: fermions and bosons. The Higgs particle is called a boson because it falls into the second category. Evidence for the Higgs boson was obtained from data collected at CERN’s Large Hadron Collider near Geneva, Switzerland, as well as at Fermilab’s Tevatron collider in the United States. Although the Higgs boson has been nicknamed the “God particle,” it is widely agreed that the name is more for publicity than accuracy, and many physicists do not like it. “I detest the name ‘God particle’. There is a tendency to intuitively think of particles as being like little round marbles. .
* Dr. [1003.4266] Predictions for Higgs production at the Tevatron and the associated uncertainties. [1012.0530] Higgs production at the lHC. [hep-ph/0101342] How Can a Heavy Higgs Boson be Consistent with the Precision Electroweak Measurements? Experiment. Caption for Figure A The Standard Model does not predict the mass of the Higgs boson, but does predict the production cross section once the mass is known. The "cross section" is the likelihood of a collision event of a particular type. ATLAS uses plots like this one to seek hints for the Higgs boson and also to exclude regions of mass where the Higgs is very unlikely to be found. This example is not real data, but is a simplified plot to show how we interpret the results of our searches for the Higgs boson.
The vertical axis shows, as a function of the Higgs mass, the Higgs boson production cross-section that we exclude, divided by the expected cross section for Higgs production in the Standard Model at that mass. This is indicated by the solid black line. This shows a 95% confidence level, which in effect means the certainty that a Higgs particle with the given mass does not exist. The red-gray shaded regions show what is excluded. At Long Last, The Higgs Particle... Maybe. Copyright © 2012 NPR. For personal, noncommercial use only. See Terms of Use. For other uses, prior permission required. This is SCIENCE FRIDAY; I'm Ira Flatow. It's the moment physicists had been waiting for for decades, the discovery of the elusive Higgs boson or at least a particle that looks a lot like it.
Some have compared the news to the splitting of the atom or discovering the structure of DNA. But I know some of you are out there saying big deal. Sean Carroll is a theoretical physicist at Cal Tech and author of the forthcoming book "The Particle at the End of the Universe," and it's about the search for the Higgs. SEAN CARROLL: Thanks, Ira, good to be here. FLATOW: Do you have to change the ending of your book? CARROLL: I have to change much of my book yes, that's right, but it's in a very good way. FLATOW: Is it for sure that they have found the Higgs? CARROLL: No, it's for sure that they have found a particle. In fact, we're all hoping that it's not. CARROLL: Absolutely. [hep-ph/0305237] Gauge Theories on an Interval: Unitarity without a Higgs.
[hep-ph/0308038] Towards a Realistic Model of Higgsless Electroweak Symmetry Breaking. Higgs_s055-web.dvi - rpp2012-rev-higgs-boson.pdf. Why does the Higgs decay? | Lily Asquith | Life & Physics | Science. The experiment I work on is based around a particle detector which we lovingly refer to as ATLAS. ATLAS is an enormous and highly intricate piece of equipment, designed and built on the blood and sweat (we don't produce tears) of thousands of people over two decades, and the main motivation for all this is to find or exclude the existence of the predicted "Higgs" boson. The ATLAS detector can be thought of as a giant camera with many different parts, each with different sensitivities, just as we are used to film cameras being sensitive to visual and audio input of widely varying types.
But, it is not capable of directly observing the Higgs boson. We can't take a picture of this thing: no detector can. This tendency to decay is true of most fundamental particles, but why? It feels sensible to divide this statement "If it can happen, it will happen" into two parts: the "CAN" and the "WILL". This is the "WILL" happen bit. Some people started blogging rumours of a discovery this week. [1106.0034] Theory and phenomenology of two-Higgs-doublet models. Quantum Diaries. The Higgs boson plays a key role in the Standard Model: it is related to the unification of the electromagnetic and weak forces, explains the origin of elementary particle masses, and provides a weakly coupled way to unitarize longitudinal vector boson scattering. As particle physics community eagerly awaits CERN’s special seminar on a possible Higgs discovery (see Aidan’s liveblog), it’s a good time to review why Higgs—the last piece of the Standard Model—is also one of the big reasons why we expect even more exciting physics beyond the Standard Model.
The main reason is called the Hierarchy problem. This is often ‘explained’ by saying that quantum corrections want to make the Higgs much heavier than we need it to be… say, 125-ish GeV. Before explaining what that means, let me put it in plain language: The Higgs has a snowball’s chance in hell of having a mass in that ballpark. This statement works as an analogy, not just an idiom. Quantum corrections: the analogy of the point electron 1. The Hierarchy Problem. What is the Hierarchy Problem? An important feature of nature that puzzles scientists like myself is known as the hierarchy, meaning the vast discrepancy between aspects of the weak nuclear force and gravity. There are several different ways to describe this hierarchy, each emphasizing a different feature of it. Here is one: The mass of the smallest possible black hole defines what is known as the Planck Mass. When faced with such a large number as 10,000,000,000,000,000, ten quadrillion, the question that physicists are naturally led to ask is: where did that number come from?
But while trying to figure out a possible explanation, physicists in the 1970s realized there was actually a serious problem, even a paradox, behind this number. The non-zero Higgs field has a size of about 250 GeV, and that gives us the W and Z particles with masses of about 100 GeV. This is the hierarchy problem. Like this: Like Loading... Higgs_s055-web.dvi - higgs_s055.pdf. Higgs boson particle results could be a quantum leap. Seldom has something so small and ephemeral excited such interest. The theoretical particle explains how suns and planets formed after the Big Bang — but so far it has not been proven to exist. The CERN research centre near Geneva will on July 4 unveil its latest findings in the search for the Higgs after reporting “tantalising glimpses” in December.
Scientific bloggers and even some of the thousands of physicists working on the project are speculating that CERN will finally announce proof of the existence of the Higgs. “It’s still premature to say anything so definitive,” says CERN spokesman James Gillies, adding the two teams involved are still analysing data and even CERN insiders won’t know the answer until the results from both are brought together. But with plans for a news conference that will be beamed live around the world and coincide with a major particle physics conference in Melbourne, Australia, anticipation of a significant announcement is hard to avoid. Smashing watermelons. Higgs on way, theories thicken. New Delhi, July 3: Peter Higgs, an 82-year-old British physicist, will be among guests in a Geneva laboratory tomorrow morning to hear scientists unveil the latest results of their search for a subatomic particle he had predicted 48 years ago.
Laboratory officials said Higgs and three other physicists who had proposed a theory that would imply the existence of a new fundamental particle, which would be called the Higgs boson, are expected to be at the scientific seminar on the results. Their expected presence has heightened speculation that the experimental teams looking for the Higgs boson, popularly dubbed the “God particle”, might announce a discovery or at least very strong evidence for the particle. The Higgs boson is the last missing piece of an elegant, mathematical theory of nature that explains almost all forces and particles known in the universe except gravity. The scientific seminar will begin in CERN’s main auditorium at 9am local time (12.30 IST) and webcast. Higgs boson behaving as expected - Story - Environment/Sci. By Dan Satherley CERN scientists working at the Large Hadron Collider have good news and bad news to report. The good news is further research has shown the particle discovered in July is likely to be the Higgs boson they had been hunting for nearly five decades.
But that's also the bad news. Initial testing suggested the particle could have been something more exotic than the basic Higgs boson, whose existence was first postulated in the mid-1960s to fill in gaps in the Standard Model, scientists' current best understanding of physics. This would have opened up new areas of research, allowing scientists to increase their understanding of the universe and strange phenomena like dark energy. But new data released at a conference in Kyoto this week has failed to show the particle is behaving any differently to what the Standard Model had predicted. "What we are likely to see is some incremental changes in what we know. " "Knowledge about nature does not come easy," writes Strassler. 3 News. The Crisis of Big Science by Steven Weinberg.
Last year physicists commemorated the centennial of the discovery of the atomic nucleus. In experiments carried out in Ernest Rutherford’s laboratory at Manchester in 1911, a beam of electrically charged particles from the radioactive decay of radium was directed at a thin gold foil. It was generally believed at the time that the mass of an atom was spread out evenly, like a pudding. In that case, the heavy charged particles from radium should have passed through the gold foil, with very little deflection. To Rutherford’s surprise, some of these particles bounced nearly straight back from the foil, showing that they were being repelled by something small and heavy within gold atoms. Rutherford identified this as the nucleus of the atom, around which electrons revolve like planets around the sun. This was great science, but not what one would call big science. Nuclear physics soon got bigger. After World War II, new accelerators were built, but now with a different purpose.
Peskin.pdf. Frequently Asked Questions: The Higgs! Why have we tried so hard to find the Higgs particle? How does the Higgs mechanism work? What is the difference in physics between strong evidence and a discovery? Why do physicists speak in terms of "sigmas"? Find out here! Why have we tried so hard to find the Higgs particle? Because it could be the answer to the question: how does Nature decide whether or not to assign mass to particles? How does the Higgs mechanism work? According to the Englert-Brout-Higgs mechanism, the property that we measure as the ‘mass’ of a particle is the result of a constant interaction with a field that permeates the Universe like a sort of “ether”. Originally, the Englert-Brout-Higgs mechanism was put forward to explain why one of Nature’s fundamental forces has a very short range, whereas another similar force has an infinite range. It should not be thought that the Englert-Brout-Higgs field is responsible for all the mass in the Universe.
Is the Higgs boson the only possible answer to the “mass problem”? A Higgs by Any Other Name « NOVA's Physics Blog: The Nature of Reality. Physicists are on the brink of a breakthrough discovery: They may have finally cornered the Higgs boson, the subatomic particle hypothesized to give mass to all the stuff in the universe.
But should we really be calling this particle the “Higgs”? A computer simulation of a detection of the Higgs boson. Or is that the ABEGHHK’tH boson? Credit: David Parker/Photo Researchers, Inc. Peter Higgs, it turns out, wasn’t the only one to come up with the idea of a new field (the Higgs field) that endows particles with mass. In fact, he wasn’t even the first to publish the theory. This wasn’t plagiarism: It was a kind of synchronicity that is the norm in science, says MIT science historian David Kaiser. Higgs, Brout, Englert and the rest were continuing a tradition that is as old as physics itself.
Higgs himself has always been uncomfortable seeing his name ride solo. Complicating matters is physicists’ anarchic naming methodology. So what should we be calling the Higgs? Twin Peaks in ATLAS. For the annual December CERN council meeting the ATLAS experiment provided an update of the Higgs searches in the γγ and ZZ→4 leptons channels. The most interesting thing about the HCP update a month ago was why these most sensitive channels were *not* updated (also CMS chose not to update γγ). Now we can see why. The ATLAS analyses in these channels return the best fit Higgs masses that differ by more than 3 GeV: 123.5 GeV for ZZ and 126.6 GeV for γγ, which is much more than the estimated resolution of about 1 GeV. The tension between these 2 results is estimated to be 2.7σ.
Apparently, ATLAS used this last month to search for the systematic errors that might be responsible for the discrepancy but, having found nothing, they decided to go public. One may be tempted to interpret the twin peaks as 2 separate Higgs-like particles. The truly exciting thing about the new ATLAS results is that the diphoton rate continues to be high. Higgs-like Particle in a Mirror. Physicists have been searching for the Higgs boson for nearly years. In July 2012, two collaborations at the Large Hadron Collider at CERN announced the discovery of a new particle that meets the general expectations for a Higgs boson. But is this particle the final piece of the standard model, or something more exotic?
One important test is the parity of the particle: how its mirror image behaves. In a mirror, even-parity particles look the same, whereas odd-parity particles appear reversed. The standard model Higgs boson is a scalar, a spin- even-parity particle. For the first time, the CMS Collaboration at the LHC has placed constraints on this possibility. RÉSONAANCES: When shall we call it Higgs? Quantum Diaries. A question of spin for the new boson. Will our universe end in a 'big slurp'? Higgs-like particle suggests it might. The Year Of The Higgs, And Other Tiny Advances In Science. Higgs Boson Discovery Has Been Confirmed. Experiments observe particle consistent with long-sought Higgs boson. Higgs particle looks like a bog Standard Model boson, say scientists | Science. Higgs Results at Kyoto. Higgs boson: the particle of faith.
Physics Letters B - Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC. [1110.2253v1] The Beginnings of Spontaneous Symmetry Breaking in Particle Physics -- Derived From My on the Spot "Intellectual Battlefield Impressions" [0907.3466] The History of the Guralnik, Hagen and Kibble development of the Theory of Spontaneous Symmetry Breaking and Gauge Particles. Englert-Brout-Higgs-Guralnik-Hagen-Kibble mechanism (history) My Life as a Boson - MyLifeasaBoson.pdf.
Higgs Boson wih Sean Carroll - Sixty Symbols. What exactly is the Higgs boson. Birth of a new particle | Jon Butterworth | Life & Physics | Science. Origins: CERN: Tools: The Higgs Boson. News - India: Enough about Higgs, let's discuss the boson. What's the Matter with the Higgs Boson? Ten things you may not know about the Higgs boson. Higgs for Waldegrave. Finally - A Higgs Boson Story Anyone Can Understand. Taking a closer look at LHC - STANDARD MODEL. Higgs boson metaphors as clear as molasses - Ideas. Higgs boson: how would you explain it to a seven-year-old? | Science. Higgs Boson Explained: How 'God Particle' Gives Things Mass. Introducing the higgson. Higgs competition: Renaming the God particle | Science.