Ever SINCE GALILEO’S famous climb to the top of the Tower of Pisa, where he dropped several items and gained an insight into how gravity works, physicists have used acceleration as a tool to explore the fundamental building blocks of nature. Technological advances have helped physicists make more sophisticated machines that can now accelerate individual particles to almost the speed of light, smash them together and detect in exquisite detail the resulting explosion of tiny particles and jets of energy. Culminating with the Large Hadron Collider (LHC) at the European Organisation for Nuclear Research (CERN), near Geneva, Switzerland, the accelerators have continued to leapfrog one another in size, rate of collisions and the amount of energy used to run it.
Each one is an extravagant and exciting technological feat, pushing the frontiers of technology and resulting in some of the most complex machines in the world. The problem is, this excitement hasn’t been reflected in the physics. There haven’t been any unexpected discoveries since the 1970s. Not one significant surprise. Not because the experimentalists are doing something wrong; rather, the theory is just too good – maddeningly, frustratingly good.
The 1970s saw the finishing touches added to particle physics’ big theory, uninspiringly named the Standard Model. Incorporating all known particles and most forces, the Standard Model has been uncannily successful. It is yet to fail a single experimental test, and has predicted all subsequent particle discoveries, including the bottom quark in 1977, the W and Z bosons in the early 1980s, the top quark in 1995 and the tau neutrino in 2000. The last remaining particle predicted by the Standard Model was the Higgs boson – and its probable discovery was announced to excited crowds in Geneva and Melbourne on 4 July 2012.
NOW, PHYSICISTS ARE stuck. What if the Higgs boson behaves exactly as the Standard Model predicts? The theory would then be complete. The avenues to new physics, to new discoveries, would close. In many ways, the Higgs would be considered a disappointment.
“It is a pity, in a way, because the great advances in physics have come from experiments that gave results we didn’t expect,” Stephen Hawking told the BBC after the Higgs announcement. Hawking had often stated that he thought the Higgs boson wouldn’t be found. In 2008, when the LHC started up, he said, “I think it will be much more exciting if we don’t find the Higgs. That will show something is wrong, and we need to think again. I have a bet of $100 that we won’t find the Higgs.”
Hawking’s sentiment is reflected among many who work directly for the collaborations at CERN: “If it’s just the Standard Model Higgs that we are finding, it’s exciting… but a little boring,” says Albert de Roeck, from the CMS (Compact Muon Spectrometer) collaboration and the University of Antwerp in Belgium.
Despite its success, the Standard Model fails to explain several observations made elsewhere in physics. It has no candidates for dark matter, which makes up most of the universe; it doesn’t explain why the universe predominantly comprises matter and not antimatter; it cannot incorporate the full theory of gravity, as described by Einstein; and it cannot account for a discovery in 2002 that neutrinos must have at least a tiny bit of mass.
These observations have left physicists scratching their heads. Experimental results that point to new physics are needed for physicists to be able to find things they haven’t been able to conjure up using brainpower alone.
And that’s what may be happening. As the physicists accumulate more and more data from the LHC, they are seeing tantalising hints that the Higgs boson may not behave exactly as predicted by the Standard Model. There’s something weird about why its mass was right at the low end of what was possible, and early results show that it exhibits a strange type of decay. What all this means is that the particle announced in July is either the very last piece of the Standard Model, or the first particle of something new and entirely bizarre.
IN THE SMALL HOURS of July 4, exhausted but excited postdoctoral and postgraduate students camped outside the main auditorium at CERN, hoping to make it in for the much-anticipated announcement from the scientists working on the ATLAS and CMS collaborations, which run the two largest detectors on the LHC. The auditorium was too small to hold the thousands of experimental physicists who work there, as well as the journalists and prominent theoretical physicists who had made the journey to CERN to hear the results. One of the key figures in the auditorium was British theoretical physicist Peter Higgs, after whom the particle was named.
It had been 48 years since the Higgs boson was first predicted, the longest time between prediction and discovery for any particle. In the 1960s, Higgs, and two other groups comprising Robert Brout, François Englert, Gerald Guralnik, Carl Hagen and Tom Kibble, first proposed the existence of a field that permeates all space. They thought the field should give particles their mass as they move through it, like some invisible cosmic treacle that slows them down. Without the field, all particles would travel at the speed of light for eternity, never slowing down to make atoms, planets and galaxies, let alone the complex molecules that make up life. Of these six physicists, Higgs was the only one who explicitly stated that there would be a new particle, the result of an excitation or ‘vibration’ of the field. Because of this, the particle and field took on his name.
In a two-hour presentation in July, two collaborations announced an observation of a new particle, in the mass range of 125–126 gigaelectron volts (GeV) – about 126 times the mass of a proton. It was the long-awaited proof that physicists truly understand the origin of mass, and was delivered to thundering applause. The announcement ricocheted around the world, dominating Twitter for hours and headlining more than 5,000 news websites. It was called “science’s great leap forward” by The Economist and likened to the discovery of DNA.
Towards the end, Higgs, who has often evaded the media, was asked to comment. “I would like to add my congratulations to everyone involved in this achievement,” he said. After a pause, he added, “It’s really an incredible thing that it’s happened in my lifetime.”
“WE HAVE TO BE PRECISE in what we mean by ‘Higgs boson’ because the Higgs boson is a general class of particles,” says British physicist Richard Hawkings, who was the physics coordinator of the ATLAS collaboration at the time of the discovery. “The simplest version of this is the Standard Model Higgs boson, which means that there is only one Higgs boson.”
Several other theories, not included in the Standard Model, predict there may be more Higgs bosons. Supersymmetry is one, and it proposes that for every particle, there is a heavier ‘super-partner’ particle. In the simplest version of supersymmetry, there are no fewer than five Higgs bosons: three of them neutral, one positively charged and one negatively charged. It could be that the LHC discovery is one of the Higgs bosons of supersymmetry.
One of the clues to its true identity is in how it decays. The Higgs boson – or, rather, all the Higgs bosons – are very unstable, short-lived particles, which quickly decay into other particles. There are several possible decays, among them: into two Z bosons; two photons; two bottom quarks; two tau leptons; or two W bosons.
“The most important decay is the two photon decay – both ATLAS and CMS have seen more of this decay than the Standard Model predicts. If this trend continues as we add more data this year, this would be not just a discovery of the Higgs boson, but a discovery of some new physics,” says Christopher Hill from Ohio State University in Columbus, and the deputy physics coordinator for the CMS collaboration.
“We see it at a rate that is higher than what is expected by the Standard Model. However, the uncertainties are not small enough that we should be making any statement that this is not consistent with the Standard Model,” says Hawkings. “Of course, there’s a lot of speculation. But for me, I’d want to see more data before I could be convinced.”
They haven’t yet observed the Higgs decay into leptons, or into quarks, which they would expect if it behaved as the Standard Model predicts. But these two types of decay are very difficult to detect. More data is needed before they’ll know if there is truly a signal, and this is “the next big question that we have to answer,” says Hawkings.
THERE IS ANOTHER hint from the Higgs boson that suggests this is not the end of the story: the mass of the boson itself. “What is rather strange is that the mass of the Higgs boson is quite low, at 125GeV. It’s right on the low end of the range. And many, many theoretical physicists believe that this indicates there is actually something else to be found, something that keeps the Higgs mass low,” says Hawkings.
The mass of the Higgs boson has contributions in quantum mechanics from many different particles. “This Higgs boson is not just a particle sitting there by itself, it’s surrounded by a cloud of other particles, coming in and out of existence. For example, its mass is affected by quarks, in particular the top quark, which is very heavy. When you calculate its mass, these corrections come in and they try to push its mass higher.
“Now, if there are some other particles, for example in the theory of supersymmetry, the top quark has a partner called the ‘stop’ or the ‘top squark’ and that will tend to cancel the effect of the top quark pushing the Higgs boson’s mass higher. So, the fact that the Higgs boson’s mass is quite low indicates that there may be other particles lurking just around the corner.”
The theory of supersymmetry is also popular among physicists because it is mathematically elegant; it ties up a lot of loose ends in their equations. And it holds the promise of helping solve some of the outstanding anomalies, such as candidate particles for dark matter.
“Supersymmetry provides a very good candidate for dark matter particles that maybe have been produced a short time after the Big Bang and have survived until now,” says Peter Jenni, former spokesperson for the ATLAS collaboration. The key particle is the lightest supersymmetric particle (LSP) that is stable and has no charge. Normally, it would not be produced directly, but is the end product of the decay chain of much heavier supersymmetry particles.
“The energy densities were only high enough in the universe shortly (0.00000000001 seconds) after the Big Bang for the production of heavy supersymmetry particles. After that, the universe expanded and cooled down. So, enormous numbers of LSPs [could have] survived since then, and as they feel gravitation like all other particles, they also gathered in the visible galaxies,” says Jenni.
If they do indeed exist, heavy supersymmetry particles could be produced inside the LHC. “ATLAS and CMS search intensively for supersymmetry particles at the LHC, which could have enough energy to produce them. One would observe the particles – ordinary jets [of energy] and leptons – into which they decay, plus missing transverse energy because the neutral LSP would escape the detector without leaving any track,” Jenni adds.
MEANWHILE, DATA CONTINUES to pour from the LHC. But from early 2013 until mid 2014, the accelerator will be shut down to undergo maintenance and upgrade work. When it starts up again, it will perform at double the energy, to reach the full design energy of the accelerator.
Results from the last round of data collection, from 2012, will be revealed in March 2013, but it may or may not be the last word on the Higgs.
“We’ll be back in 2015, taking more data,” says Hawkings. “This will allow us to explore more about the Higgs boson, hopefully shed some more light on these other questions, such as whether supersymmetry exists, whether there are other new things out there, it may shed some light on questions about dark matter… and hopefully some new discoveries.”
By then, physicists should know whether their Standard Model theory is complete, or if there is a bright new future for particle accelerators and physicists in working out the details of an entirely new model.
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within my small knowledge and informations available in blogs- The total spin of LHC boson could discriminated between “2″ and “0″.
Theory predicts the existence of two bosons whose spin differs from 1. The force carrier for gravity is the hypothetical graviton; theory suggests that it has s = 2. The Higgs mechanism predicts that elementary particles acquire nonzero rest mass by exchanging Higgs bosons with an all-pervasive(transcendence) Higgs field. Theory predicts that the Higgs boson has s = 0. If so, it would be the only elementary particle for which this is the case.
Measuring the total spin of fermions and bosons is consistent, but why not with Higgs boson?. If it is 0 spin, there is no decay into other particles to measure the spin?. A component of spin can be increased or decreased with “raising” and “lowering” operators, and the change is always in natural units of 1- means, the existence of two bosons whose spin(s) differs from 1- between gravitational field and Higgs field.
Higgs boson “jitter”(spin 0 and 2) its behaviour between gravitional force and electroweak force?. So measurement can appear “simultaneously” in different spacetime metric like in Schrödinger’s cat analogy?.
We may have another analogy: A car(Higgs boson) is running on a perfectly smooth road at the speed of light C(higgs field). Suddenly it applies the break and create resistance on the road(spacetime metric).
This inertial resistance will create energy(inertial mass).
If the car again starts to run at the speed C. If this repeated “jitter” happens simultaneously- will maintain “symmetry breaking” between gravitational force and electroweak force?
For the persons inside(fermions or Goldstone bosons+W&Z bosons) the car, It appears(human perception), the two jittering conditions compressed and “appears” as matter??.
Higgs boson keeps the symmetry breaking between electroweak force and gravitational force??
http://profmattstrassler.files.wordpress.com/2012/08/spring_qu2_sm.gif
http://www.youtube.com/watch?v=IOYyCHGWJq4
http://profmattstrassler.files.wordpress.com/2012/08/spring_qu2_sm.gif
profmattstrassler.files.wordpress.com
“The Standard Model still rules OK, but the main test will come when the gamma rates are updated.”
If we could manipulate the Higgs Boson, to simulate large amounts off mass; wouldn’t gravity come right along with it?
Gravity means, artificial gravity, I’m speaking of the sci-fi variety. (Gravity plating).
That’s not really “artificial gravity”, that’s “artificial mass”. Horse of a different color.
Sure if we had unlimited energy maybe. The LHC uses 92 megawatts per hour to run according to this page:
http://science.howstuffworks.com/sci…-collider3.htm
….and according to wiki it will produce “a single higgs boson every few hours”.
http://en.wikipedia.org/wiki/Large_Hadron_Collider
You’d need the energy output of a star to manipulate gravity in any meaningful way.
More mass means more force needed to accelerate. That would make it a fairly useless technology for travel.
What if it were less mass? Then we’d have something approaching an inertialess drive. Assuming, of course, that this discovery leads to some practical way to (1) extract the mass from matter (2) without destroying it. Don’t look for that this century if ever.
So now you’re talking about not “adding” Higgs bosons to objects to create extra mass and therefore artificial gravity, but taking them away to create a craft with almost zero mass that requires only a tiny amount of force to accelerate?
The Higgs Boson is an artifact of the Higgs Field.
It is the Higgs Field that gives things mass. The Higgs Boson is merely a byproduct that tells us the Higgs Field is there (which we cannot measure directly).
Thus manufacturing Higgs Bosons gets you nothing. Hell, the LHC did not even see a Higgs Boson. They decay far too rapidly to be observed. What they see is a teeny (and I am talking factions of a fraction of a percent) variation in the stuff it decays into to deduce it was even there in the first place.
In short, we cannot make any use of the Higgs Boson directly. Even if we could hang on to one for any length of time beyond micro-fractions of a second I am not sure you could make any use of them.
Mass (of elementary fermions, i.e. matter particles) is given by the coupling of the fermion to the Higgs field, so we’d need to figure out a way of ‘tuning’ this coupling in order to produce any effect.
If you’ve got a bit of a background in physics/are willing to overlook a few equations, Frank Wilczek’s article ‘Origins of Mass’ gives a good overview.
better still, antigravity — then, we don’t need to decouple matter from mass; we need to decouple mass from gravity. Is that theoretically possible? There are hypothetical “gravitons,” and maybe identifying the Higgs boson could give us a handle on gravitons, which are presumably another type of boson. But, as I very imperfectly understand it, gravitons, if they exist, mediate gravity only at subatomic distances; gravity at any greater distance or scale is purely a matter of spacetime-curvature induced by the presence of fermion-mass-in-the-aggregate — therefore, manipulating gravitons would not allow us to, say, cancel out or reverse a planet’s gravitational field at the level necessary to launch a spaceship, or even to keep Luke Skywalker’s landspeeder hovering above the ground. Am I wrong?
Artificial gravity(as distinct from antigravity) is something we easily can make already, just by spinning the spaceship like a tilt-a-whirl.
There may or may not be gravitons, gravity may or may not actually exist, and if it does we probably can’t generate or destroy it. The problem is that our means of testing is rather limited. We know less about gravity than any of the other forces (which are probably a single force). Gravity exists – we can measure and predict it. But we don’t know why it exists at all.
Of the four fundamental forces gravity is the holdout. Quantum Mechanics is perhaps the most successful theory ever put forward by man. It has been tested repeatedly to insane levels of precision and so far it has never failed.
Never failed that is till you mix gravity into the equation then it all goes to hell in a big way. Relativity, which deals with gravity, is likewise a hugely successful theory and been proven over and over again.
But the two do not play nice together at all. The theory of the very large and the theory of the very small are anathema to each other.
Gravitational mass and inertial mass are not the same thing. In the equivalence principle states that inertial and gravitational mass are equivalent, but they’re not the same thing. One is a result of the Higg’s field and binding energy, the other comes from gravity. Dropping a block of wood on your toe hurts like hell, so does stubbing your toe on it. Same injury, same result, but differing sources of pain: gravity and inertial mass.
The Higgs Boson is what gives things mass. Mass in turn creates gravity. But the Higgs Field is not gravity.
In zero g you still have the same mass.
In a weightless environment, water still has the same amount of inertial mass. So does everything else in your body. Water (H2O) in space is just as good for you as water on earth. However, as the article cites, heavy water(HDO, D2O, TDO, THO, T2O ) is bad for you even on earth.
General relativity follows essentially from two postulates, the general principle of relativity (which says that physics does not depend on the choice of coordinates) and the equivalence principle (you can’t locally tell the difference between acceleration and the effect of a gravitational field). Both are, of course, not proven — they’re postulates, and the other forces depend on postulates of their own — but it would just be a weird universe in which it made a physical difference what numbers we use to coordinatize a manifold, for example. And the understanding of gravity that follows from these assumptions is just as complete (or incomplete) as we have for the other forces, and just as much in account with experiment.
We know there’s something that behaves very much like anti-gravity, known as dark energy. This can be, for instance, sourced by a fluid with negative pressure, and there’s no a priori reason such a thing can’t exist.
Of the four fundamental forces gravity is the holdout. Quantum Mechanics is perhaps the most successful theory ever put forward by man. It has been tested repeatedly to insane levels of precision and so far it has never failed.
Never failed that is till you mix gravity into the equation then it all goes to hell in a big way. Relativity, which deals with gravity, is likewise a hugely successful theory and been proven over and over again.
But the two do not play nice together at all. The theory of the very large and the theory of the very small are anathema to each other.
So, in a sense we do not know what to make of gravity. It is the only one of the four fundamental forces you cannot shield yourself against. It is by FAR the weakest of the forces (by orders of magnitude) yet in some cases it can overwhelm everything else (think black holes).
Relativity says gravity is essentially the curvature of space. Mass curves space and we follow that curve akin to a marble rolling across a sheet with a bowling ball in the middle. In order to “make” gravity you need mass. Want 1g of gravity on your spaceship? Then you need the mass of the earth to generate it.
Anti gravity would be reversing the curvature which would need negative matter (not antimatter…antimatter is real). We’ve never seen negative matter though and haven’t a clue how to make it and it probably isn’t even possible.
So, in short, gravity is the fly in the ointment. The Higgs Boson discovery is cool and a step forward but we have a long way to go yet.
I don’t think the qualities required for The Higgs particle to explain the standard model is there, and I don’t think they will be found.
Neither do I think, that supersymmetry will be recognized in futuristic science.
I know I am a pain in the butt, but I believe in a complete different approach to high energy physics in the future. My vision is that future science will engulf consciousness. The mind and the spirit will be explainable through physics.
I have been a fan of Sir Roger Penrose for many years. He was the first scientist to say that consciousness should be found in the quantum field rather than in the brain. I am so much a fan, that I made my own theory out of the idea that consciousness might be explained through a better understanding of antimatter and multiverse dimensions.
My idea is that antimatter is the mirror of this universe, and that antimatter might be where memory is located.
I think that the subconscious mind and consciousness are located in multiverse dimensions in the form of antimatter.
The original standard model predicted no mass at all. That made no sence to scientists, so Peter Higgs predicted The Higgs Boson, purely from mathematics. I think the original standard model was right, particles does not exist. The physical universe is a flow of energy from minus infinite energy to plus infinite energy.
If you would like to know more, then you can watch a full videopresentation of my theory on my blog:
http://www.crestroy.com
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