Posts Tagged ‘HIGGS

Answering your Higgs questions

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Scientists at the Large Hadron Collider (LHC) announced the discovery of a Higgs-like boson on July 4 – but what does that mean? What’s a Higgs boson? And how can a particle be like a Higgs? Read on to learn more about the new particle and how it fits into our world.

The following questions were asked on Twitter on 4 July 2012, the day CERN announced the discovery of a new particle with a mass of approximately 126 GeV.


How many Higgs bosons are there?

In the Standard Model there is just one, but many theories predict more. For example, supersymmetry predicts at least five. Supersymmetry also predicts other supersymmetric scalar particles. Models in which the Higgs is composite with internal constituents suggest that it would be accompanied by an infinite number of other composite particles, in which the constituents are arranged in different ways.

What are the key features of this newly discovered boson that would identify it as the Standard Model Higgs?

The decay rates of the new boson could help to identify it as the Standard Model Higgs. The Standard Model predicts certain rates of decay, and, if this boson matches the expected rates, it would offer solid evidence that it is this Higgs. Also, the Standard Model Higgs should have a specific value of spin. If the spin of the new boson differs from predictions, it might be a sign of new physics.

Do you envision a time when we will be able to manipulate Higgs to do things, as we do electrons, perhaps to vary mass?

As a scientist, one should never say never, but it is not clear how it could be done. It would require achieving the same energy density as in collisions at the LHC, but over a large region of space.

What is the difference between the Higgs boson and the Higgs field? Is the field composed of Higgs bosons?

The Higgs field stretches out through the whole of the universe. A massless particle would just glide through, not interacting with the field. A heavier particle would collect more mass. It’s like a skier skimming over the top of a field of snow. The snow would barely be affected, but someone with just boots on would sink deeply into the snow. The Higgs field is the area of snow, while the Higgs bosons are the snowflakes that make up the snow covering the ground.

See video: What is the Higgs boson?

Where do the researchers go from here and how are theories relating to the theoretical dark matter affected?

We need to check whether the new particle has the essential features expected for a Higgs boson. Once we know more about the properties of this boson, we can move forwards. In many theories, including supersymmetry and some composite models, one of the particles associated with the Higgs may make up the astrophysical dark matter. Within these theories, measuring the mass and other properties of the Higgs boson can help to pin down the nature of dark matter.


Is the LHC adapted for the discovery of particles not predicted by theory? If yes how, and in which direction?

Yes. The LHC is a search-and-discovery machine. It uses composite particles (protons) as projectiles so the actual energy liberated (to be used for making new particles) in any given collision spans a wide range, covering the mass range of potential new particles. The ATLAS and CMS detectors are also multipurpose, able to detect all long-lived particles emanating from a collision, including those that arise from decays of heavier, perhaps new, particles. Papers published already by the collaborations include searches for new particles with masses of the order of 1-2 TeV. When the LHC increases in collision energy to 13-14 TeV in 2015 these searches can be extended to much higher energies.

How much data will be needed to isolate the nature of this new particle and possibly identify it as the Higgs boson?

It is very early days! The number of Higgs-boson candidates identified so far is of the order of tens. This is sufficient to be able to understand some basic properties, but not enough to determine details. For example, we know that its spin value must be an integer, but not 1, so does it have spin 0, as expected, or spin 2, say? It’s not yet possible to determine in which of many theories this particle fits. It certainly has properties consistent with the predicted Standard Model Higgs boson but these are very similar (with the current statistics) to the lightest neutral supersymmetric (SUSY) Higgs boson. And some SUSY models predict five Higgs-like bosons! By the end of 2012, the data samples of ATLAS and CMS should at least double, and this should point the way to which theory fits best. But it may be several more years before we understand the details – and indeed this new boson may not fit precisely into any current theory.

The discovery of the Higgs has been hailed as completing the Standard Model. What happened to the graviton?

The graviton has never been a component of the Standard Model. The gravitational force, for which the graviton is the postulated force-carrier, is far too weak to influence the quantum world. Some exotic theories, such as string theory, are attempting to unify all four known forces, but as yet there are no testable quantities.

Assuming the upcoming analysis of the boson turns out to show that it is the expected Higgs, what will be the LHC’s next task (What will the LHC look for now)?

The analysis of the newly discovered boson will certainly take many years. The amount of data so far accumulated is around 2% of that expected for the lifetime of the LHC (until around the year 2022). So this is just the beginning of the story.

Moreover, there are still many unanswered questions that are being tackled in parallel to the origin of mass that the Higgs boson addresses. For example, we know that 96% of the universe is not baryonic matter (the stuff we, the planets and the stars are made of); the nature of this dark matter and dark energy may be elucidated by ATLAS and CMS. And where has all the antimatter – assuming that it was created in equal amounts to normal matter at the time of the big bang – gone? This is something that LHCb in particular is tackling, as well as ATLAS and CMS. The ALICE collaboration plans to study quark-gluon plasma, believed to be present in the moments after the big bang, as it expends and cools, observing how it progressively gives rise to the particles that constitute the matter of our universe today.

But perhaps the most fascinating possibility is that the experiments at the LHC will discover things that we have not even contemplated, something new and unusual that pushes our knowledge forwards in ways we simply cannot predict.

Does today’s announcement mark the triumph of supersymmetry, or make it more likely?

Neither. It is far too early to determine whether the new boson belongs to supersymmetry, the Standard Model or something else.

How many particles were used and collided when this particle was found?

500 trillion – that’s a million million particles!

Future research

If the Higgs boson is discovered will that mean the end of CERN and its work?

Not at all. Once the Higgs boson is officially discovered, there are more questions. Scientists will continue to study the boson to figure out the way it works, as well as how it fits into current models as predicted, or if it has other aspects that may point to new physics.

CERN’s researchers conduct many more studies beyond the search for the Higgs. There are experiments looking for extra dimensions, dark matter and completely new physics. CERN also houses an antimatter facility. There, scientists are studying the properties of antimatter to figure out why, if antimatter and matter were produced in equal amounts during the big bang, there’s more matter in the universe now.

Do you think the public will maintain an interest in the Higgs boson as you continue to explore its properties?

We hope so. Once we know enough about the Higgs-like boson to confirm that it either is the Standard Model Higgs boson or it isn’t, there will be studies to examine exactly how the boson interacts with other particles – giving us more clues to the origin of mass and the beginning of the universe. And if this new boson is not the Standard Model Higgs boson, that’s a sign of new physics beyond the Standard Model. It’s an exciting time, and everyone should stay tuned.

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Written by physicsgg

July 27, 2012 at 4:33 pm

Posted in High Energy Physics

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Finally – A Higgs Boson Story Anyone Can Understand

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Einstein famously marveled over the idea that the universe was comprehensible. But on July 4, the universe started to sound weird and unnecessarily complicated. Physicists worldwide were celebrating an elusive thing called the Higgs Boson, which had apparently made a brief appearance.

They kept repeating that it was important because it gives matter mass, but they didn’t say how such an important job can be done by a particle that needs an $8 billion device to coax it into existence for less than a nanosecond before it returns to oblivion.

The news sounded more like the twisted logic of credit default swaps than the rational progression of science. But now that the physicists have had time to catch up on their sleep and science reporters have recovered from their 4th of July hangovers, a coherent and even comprehensible picture is starting to emerge.
And who better to tell the story than Higgs the cat. I’ve decided to ask a few very simple questions to help Higgs spin the tale. (A similar story will appear Monday in the Health and Science section of the Philadelphia Inquirer).

FF:If the Higgs particle is the answer, what was the question?

Higgs: Some scientific endeavors rest on so many layers of questions that it’s possible to lose track of where it all started. At bottom is usually a puzzle that even children can understand.
You can trace the search for the Higgs back 2,400 years. In ancient Athens, philosophers asked whether you could break matter into infinitely small pieces, or whether you would eventually get to a smallest possible piece that could not be divided.
One philosopher, Democritus, wondered whether such indivisible particles could possibly make up everything on heaven and earth. In his vision, the cosmos was just matter and void, and matter was just different combinations of atoms. His was a big, forward-thinking idea.

Democritus got the idea from his teacher Leucippus, according to the book The Dream of Reason by Anthony Gottlieb. The idea itself may be as old as human reason, but once Democritus articulated it and gave it a name – atomism – it took on a continuous life, threading through history for more than two millennia….
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Written by physicsgg

July 16, 2012 at 1:37 pm

Posted in High Energy Physics

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Unveiling the Higgs mechanism to students

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Giovanni Organtini
In this paper we give the outline of a lecture given to undergraduate students aiming at understanding why physicists are so much interested in the Higgs boson. The lecture has been conceived for students not yet familiar with advanced physics and is suitable for several disciplines, other than physics. The Higgs mechanism is introduced by semi-classical arguments mimicking the basic field theory concepts, assuming the validity of a symmetry principle in the expression of the energy of particles in a classical field. The lecture is divided in two parts: the first, suitable even to high–school students, shows how the mass of a particle results as a dynamical effect due to the interaction between a massless particle and a field (as in the Higgs mechanism). The audience of the second part, much more technical, consists mainly of teachers and university students of disciplines other than physics….
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Written by physicsgg

July 12, 2012 at 7:02 pm

Posted in EDUCATION, High Energy Physics

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Boson-spotter’s guide helps you decode the Higgs

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The elusive Higgs boson, or something very close, has finally been spotted at CERN’s Large Hadron Collider near Geneva, Switzerland. The next challenge is to pin down whether the new particle is the boson physicists were expecting or some other beast.

One of the first things physicists want to know about the new particle is itsspin, a quantum property that is analogous to the angle of the axis of rotation of a particle. They also want to know whether it has parity, a property most easily explained as whether a particle is identical to its mirror image – or more like your left and right hands. Perhaps most importantly, they will investigate seeming deviations in the rates that the Higgs decays to certain particles compared with the predictions of the standard model of particle physics.

All these things will help determine whether the new particle merely completes the standard model, offers hints to an elegant, more comprehensive extension – supersymmetry – or demands something else totally new.

You can read more about all this – and what it means for physics – in our special report: Beyond the Higgs. To help make sense of the different options, and to illustrate just what the different possibilities are, we drew up the flowchart below:

It’s not clear when we’ll have answers to the questions – the best-case estimates say by the end of the year. In the meantime, take pleasure in the fact that almost anything is still possible.

Written by physicsgg

July 12, 2012 at 2:48 pm

Posted in High Energy Physics

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Higgs Boson Music: What Might Quarks Sound Like?

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Using a data “sonification” process, researchers at the pan-European GÉANT network have created melodies from the results of the Atlas experiment at the Large Hadron Collider – the experiment that found the so-called ‘God Particle’

Written by physicsgg

July 11, 2012 at 7:40 pm

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Higgs Boson May Be An Imposter, Say Particle Physicists

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At least two other particles could be masquerading as the God particle, according to a new analysis of the data from CERN

The news coming out of CERN in recent weeks has been hard to miss. At first, there was a dripfeed of gossip which turned into a firehose of ‘Higgsteria’. Finally, last Wednesday, CERN announced that it had found a new particle that is “consistent with the long-sought Higgs boson”.

Note the phrasing. CERN has been careful not to claim that the new particle is the Higgs, only that it could be.

But if not the Higgs, what else might it be?

Today, Ian Low at Argonne National Laboratory in Illinois and a couple of buddies comb through the data in an attempt to throw some light on this question. Their conclusion is that the data is consistent with at least two other particles that are not the standard Higgs boson.

Particle identification is not always an easy task. Physicists use a theory known as the Standard Model of particle physics to predict how particles should behave. In 1964, Peter Higgs and others used this theory to predict the existence of the Higgs particle. They said it should be heavy and that it should exist only fleetingly before decaying into various other particles.

In fact, its existence is so fleeting that the only way of spotting the Higgs is to look for the signature of particles that it produces, such as pairs of photons or pairs of other heavy particles called Z bosons.

The trouble is that this signature is not unique, at least not given the amount of data that CERN has so far collected.

Low and co say that given various  assumptions about the data, there are several theoretical possibilities. One of these is that the data shows the Higgs boson as predicted by the Standard Model.

But another equally likely option is that the data is evidence of a more exotic theory in which the Higgs boson exists in several different forms. So the new particle might be one of these, examples of these are a generic Higgs doublet or a triplet imposter.

A final option is based on the idea that particles can exist in mixtures. So the new data does not show the Higgs but a mixture of it and some other particle.

Low and co analyse the data and come to the following conclusion. “A generic Higgs doublet and a triplet imposter give equally good fits to the measured event rates.”

In particular, they say that the predicted signatures of the Higgs boson and the triplet imposter are both within one sigma of the measured value. And by one measure, the CERN data even favours the triplet imposter.

However, Low and co are quick to add that the Standard Model prediction is a slightly better fit overall.

The message here is that the data at this stage is far from conclusive and could support the existence of any of these three particles.

So now there is much to do to clarify exactly what it is that CERN has found.

As Low and co point out: “This is only the beginning of a challenging program of “Higgs Identification”.

Let the Higgsteria continue.

Ref: Have We Observed the Higgs (Imposter)?


Written by physicsgg

July 9, 2012 at 4:23 pm

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Higgs Boson Discovery Timelapse

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These animations show the Higgs Exclusion plots and Signal plots as they evolved over time until the discovery of the Higgs Boson. These were produced by viXra unofficial combinations of LEP, Tevatron and LHC data.

Written by physicsgg

July 8, 2012 at 4:16 pm

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A Moment for Particle Physics: The End of a 40-Year Story?

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The announcement early yesterday morning of experimental evidence for what’s presumably the Higgs particle brings a certain closure to a story I’ve watched (and sometimes been a part of) for nearly 40 years. In some ways I felt like a teenager again. Hearing about a new particle being discovered. And asking the same questions I would have asked at age 15. “What’s its mass?” “What decay channel?” “What total width?” “How many sigma?” “How many events?”

When I was a teenager in the 1970s, particle physics was my great interest. It felt like I had a personal connection to all those kinds of particles that were listed in the little book of particle properties I used to carry around with me. The pions and kaons and lambda particles and f mesons and so on. At some level, though, the whole picture was a mess. A hundred kinds of particles, with all sorts of detailed properties and relations. But there were theories. The quark model. Regge theory. Gauge theories. S-matrix theory. It wasn’t clear what theory was correct. Some theories seemed shallow and utilitarian; others seemed deep and philosophical. Some were clean but boring. Some seemed contrived. Some were mathematically sophisticated and elegant; others were not.

By the mid-1970s, though, those in the know had pretty much settled on what became the Standard Model. In a sense it was the most vanilla of the choices. It seemed a little contrived, but not very. It involved some somewhat sophisticated mathematics, but not the most elegant or deep mathematics. But it did have at least one notable feature: of all the candidate theories, it was the one that most extensively allowed explicit calculations to be made. They weren’t easy calculations—and in fact it was doing those calculations that got me started having computers to do calculations, and set me on the path that eventually led to Mathematica. But at the time I think the very difficulty of the calculations seemed to me and everyone else to make the theory more satisfying to work with, and more likely to be meaningful.

At the least in the early years there were still surprises, though. In November 1974 there was the announcement of the J/psi particle. And one asked the same questions as today, starting with “What’s the mass?” (That particle’s was 3.1 GeV; today’s is 126 GeV.) But unlike with the Higgs particle, to almost everyone the J/psi was completely unexpected. At first it wasn’t at all clear what it could be. Was it evidence of something truly fundamental and exciting? Or was it in a sense just a repeat of things that had been seen before?

My own very first published paper (feverishly worked on over Christmas 1974 soon after I turned 15) speculated that it and some related phenomena might be something exciting: a sign of substructure in the electron. But however nice and interesting a theory may be, nature doesn’t have to follow it. And in this case it didn’t. And instead the phenomena that had been seen turned out to have a more mundane explanation: they were signs of an additional (4th) kind of quark (the c or charm quark).

In the next few years, more surprises followed. Mounting evidence showed that there was a heavier analog of the electron and muon—the tau lepton. Then in July 1977 there was another “sudden discovery”, made at Fermilab: this time of a particle based on the b quark. I happened to be spending the summer of 1977 doing particle physics at Argonne National Lab, not far away from Fermilab. And it was funny: I remember there was a kind of blasé attitude toward the discovery. Like “another unexpected particle physics discovery; there’ll be lots more”.

But as it turned out that’s not what happened. It’s been 35 years, and when it comes to new particles and the like, there really hasn’t been a single surprise. (The discovery of neutrino masses is a partial counterexample, as are various discoveries in cosmology.) Experiments have certainly discovered things—the W and Z bosons, the validity of QCD, the top quark. But all of them were as expected from the Standard Model; there were no surprises.

Needless to say, verifying the predictions of the Standard Model hasn’t always been easy. A few times I happened to be at the front lines. In 1977, for example, I computed what the Standard Model predicted for the rate of producing charm particles in proton-proton collisions. But the key experiment at the time said the actual rate was much lower. I spent ages trying to figure out what might be wrong—either with my calculations or the underlying theory. But in the end—in a rather formative moment for my understanding of applying the scientific method—it turned out that what was wrong was actually the experiment, not the theory.

In 1979—when I was at the front lines of the “discovery of the gluon”—almost the opposite thing happened. The conviction in the Standard Model was by then so great that the experiments agreed too early, even before the calculations were correctly finished. Though once again, in the end all was well, and the method I invented for doing analysis of the experiments is in fact still routinely used today.

By 1981 I myself was beginning to drift away from particle physics, not least because I’d started to work on things that I thought were somehow more fundamental. But I still used to follow what was happening in particle physics. And every so often I’d get excited when I heard about some discovery rumored or announced that seemed somehow unexpected or inexplicable from the Standard Model. But in the end it was all rather disappointing. There’d be questions about each discovery—and in later years there’d often be suspicious correlations with deadlines for funding decisions. And every time, after a while, the discovery would melt away. Leaving only the plain Standard Model, with no surprises.

Through all of this, though, there was always one loose end dangling: the Higgs particle. It wasn’t clear just what it would take to see it, but if the Standard Model was correct, it had to exist.

To me, the Higgs particle and the associated Higgs mechanism had always seemed like an unfortunate hack. In setting up the Standard Model, one begins with a mathematically quite pristine theory in which every particle is perfectly massless. But in reality almost all particles (apart from the photon) have nonzero masses. And the point of the Higgs mechanism is to explain this—without destroying desirable features of the original mathematical theory.

Here’s how it basically works. Every type of particle in the Standard Model is associated with waves propagating in a field—just as photons are associated with waves propagating in the electromagnetic field. But for almost all types of particles, the average amplitude value of the underlying field is zero. But for the Higgs field, one imagines something different. One imagines instead that there’s a nonlinear instability that’s built into the mathematical equations that govern it, that leads to a nonzero average value for the field throughout the universe.

And it’s then assumed that all types of particles continually interact with this background field—in such a way as to act so that they have a mass. But what mass? Well, that’s determined by how strongly a particle interacts with the background field. And that in turn is determined by a parameter that one inserts into the model. So to get the observed masses of the particles, one’s just inserting one parameter for each particle, and then arranging it to give the mass of the particle.

That might seem contrived. But at some level it’s OK. It would have been nice if the theory had predicted the masses of the particles. But given that it does not, inserting their values as interaction strengths seems as reasonable as anything.

Still, there’s another problem. To get the observed particle masses, the background Higgs field that exists throughout the universe has to have an incredibly high density of energy and mass. Which one might expect would have a huge gravitational effect—in fact, enough of an effect to cause the universe to roll up into a tiny ball. Well, to avoid this, one has to assume that there’s a parameter (a “cosmological constant”) built right into the fundamental equations of gravity that cancels to incredibly high precision the effects of the energy and mass density associated with the background Higgs field.

And if this doesn’t seem implausible enough, back around 1980 I was involved in noticing something else: this delicate cancellation can’t survive at the high temperatures of the very early Big Bang universe. And the result is that there has to be a glitch in the expansion of the universe. My calculations said this glitch would not be terribly big—but stretching the theory somewhat led to the possibility of a huge glitch, and in fact an early version of the whole inflationary universe scenario.

Back around 1980, it seemed as if unless there was something wrong with the Standard Model it wouldn’t be long before the Higgs particle would show up. The guess was that its mass might be perhaps 10 GeV (about 10 proton masses)—which would allow it to be detected in the current or next generation of particle accelerators. But it didn’t show up. And every time a new particle accelerator was built, there’d be talk about how it would finally find the Higgs. But it never did.

Back in 1979 I’d actually worked on questions about what possible masses particles could have in the Standard Model. The instability in the Higgs field used to generate mass ran the risk of making the whole universe unstable. And I found that this would happen if there were quarks with masses above about 300 GeV. This made me really curious about the top quark—which pretty much had to exist, but kept on not being discovered. Until finally in 1995 it showed up—with a mass of 173 GeV, leaving to my mind a surprisingly thin margin away from total instability of the universe.

There were a few bounds on the mass of the Higgs particle too. At first they were very loose (“below 1000 GeV” etc.). But gradually they became tighter and tighter. And after huge amounts of experimental and theoretical work, by last year they pretty much said the mass had to be between 110 and 130 GeV. So in a sense one can’t be too surprised about the announcement today of evidence for a Higgs particle with a mass of 126 GeV. But explicitly seeing what appears to be the Higgs particle is an important moment. Which finally seems to tie up a 40-year loose end.

At some level I’m actually a little disappointed. I’ve made no secret—even to Peter Higgs—that I’ve never especially liked the Higgs mechanism. It’s always seemed like a hack. And I’ve always hoped that in the end there’d be something more elegant and deep responsible for something as fundamental as the masses of particles. But it appears that nature is just picking what seems like a pedestrian solution to the problem: the Higgs mechanism in the Standard Model.

Was it worth spending more than $10 billion to find this out? I definitely think so. Now, what’s actually come out is perhaps not the most exciting thing that could have come out. But there’s absolutely no way one could have been sure of this outcome in advance.

Perhaps I’m too used to the modern technology industry where billions of dollars get spent on corporate activities and transactions all the time. But to me spending only $10 billion to get this far in investigating the basic theory of physics seems like quite a bargain.

I think it could be justified almost just for the self-esteem of our species: that despite all our specific issues, we’re continuing a path we’ve been on for hundreds of years, systematically making progress in understanding how our universe works. And somehow there’s something ennobling about seeing what’s effectively a worldwide collaboration of people working together in this direction.

Indeed, staying up late to watch the announcement early yesterday morning reminded me more than a bit of being a kid in England nearly 43 years ago and staying up late to watch the Apollo 11 landing and moonwalk (which was timed to be at prime time in the US but not Europe). But I have to say that for a world achievement yesterday’s “it’s a 5 sigma effect” was distinctly less dramatic than “the Eagle has landed”. To be fair, a particle physics experiment has a rather different rhythm than a space mission. But I couldn’t help feeling a certain sadness for the lack of pizazz in yesterday’s announcement.

Of course, it’s been a long hard road for particle physics these past 30 or so years. Back in the 1950s when particle physics was launched in earnest, there was a certain sense of follow-on and “thank you” for the Manhattan project. And in the 1960s and 1970s the pace of discoveries kept the best and the brightest coming into particle physics. But by the 1980s as particle physics settled into its role as an established academic discipline, there began to be an ever stronger “brain drain”. And by the time the Superconducting Super Collider project was canceled in 1993, it was clear that particle physics had lost its special place in the world of basic research.

Personally, I found it sad to watch. Visiting particle physics labs after absences of 20 years, and seeing crumbling infrastructure in what I had remembered as such vibrant places. In a sense it is remarkable and admirable that through all this thousands of particle physicists persisted, and have now brought us (presumably) the Higgs particle. But watching yesterday’s announcement, I couldn’t help feeling that there was a certain sense of resigned exhaustion.

I suppose I had hoped for something qualitatively different from those particle physics talks I used to hear 40 years ago. Yes, the particle energies were larger, the detector was bigger, and the data rates were faster. But otherwise it seemed like nothing had changed (well, there also seemed to be a new predilection for statistical ideas like p values). There wasn’t even striking and memorable dynamic imagery of prized particle events, making use of all those modern visualization techniques that people like me have worked so hard to develop.

If the Standard Model is correct, yesterday’s announcement is likely to be the last major discovery that could be made in a particle accelerator in our generation. Now, of course, there could be surprises, but it’s not clear how much one should bet on them.

So is it still worth building particle accelerators? Whatever happens, there is clearly great value in maintaining the thread of knowledge that exists today about how to do it. But reaching particle energies where without surprises one can reasonably expect to see new phenomena will be immensely challenging. I have thought for years that investing in radically new ideas for particle acceleration (e.g. higher energies for fewer particles) might be the best bet—though it clearly carries risk.

Could future discoveries in particle physics immediately give us new inventions or technology? Years ago things like “quark bombs” seemed conceivable. But probably no more. Yes, one can use particle beams for their radiation effects. But I certainly wouldn’t expect to see anything like muonic computers, antiproton engines or neutrino tomography systems anytime soon. Of course, all that may change if somehow it’s figured out (and it doesn’t seem obviously impossible) how to miniaturize a particle accelerator.

Over sufficiently long times, basic research has historically tended to be the very best investment one can make. And quite possibly particle physics will be no exception. But I rather expect that the great technological consequences of particle physics will rely more on the development of theory than on more results from experiment. If one figures out how to create energy from the vacuum or transmit information faster than light, it’ll surely be done by applying the theory in new and unexpected ways, rather than by using specific experimental results.

The Standard Model is certainly not the end of physics. There are clearly gaps. We don’t know why parameters like particle masses are the way they are. We don’t know how gravity fits in. And we don’t know about all sorts of things seen in cosmology.

But let’s say we can resolve all this. What then? Maybe then there’ll be another set of gaps and problems. And maybe in a sense there’ll always be a new layer of physics to discover.

I certainly used to assume that. But from my work on A New Kind of Science I developed a different intuition. That in fact there’s no reason all the richness we see in our universe couldn’t arise from some underlying rule—some underlying theory—that’s even quite simple.

There are all sorts of things to say about what that rule might be like, and how one might find it. But what’s important here is that if the rule is indeed simple, then on fundamental grounds one shouldn’t in principle need to know too much information to nail down what it is.

I’m pleased that in some particular types of very low-level models I’ve studied, I’ve already been able to derive Special and General Relativity, and get some hints of quantum mechanics. But there’s plenty more we know in physics that I haven’t yet been able to reproduce.

But what I suspect is that from the experimental results we have, we already know much more than enough to determine what the correct ultimate theory is—assuming that the theory is indeed simple. It won’t be the case that the theory will get the number of dimensions of space and the muon-electron mass ratio right, but will get the Higgs mass or some as-yet-undiscovered detail wrong.

Now of course it could be that something new will be discovered that makes it more obvious what the ultimate theory might look like. But my guess is that we don’t fundamentally need more experimental discoveries; we just need to spend more effort and be better at searching for the ultimate theory based on what we already know. And it’s certainly likely to be true that the human and computer resources necessary to take that search a long way will cost vastly less than actual experiments in particle accelerators.

And indeed, in the end we may find that the data necessary to nail down the ultimate theory already existed 50 years ago. But we won’t know for sure except in hindsight. And once we have a credible candidate for the final theory it may well suggest new particle accelerator experiments to do. And it will be most embarrassing if by then we have no working particle accelerator on which to carry them out.

Particle physics was my first great interest in science. And it is exciting to see now after 40 years a certain degree of closure being reached. And to feel that over the course of that time, at first in particle physics, and later with all the uses of Mathematica, I may have been able to make some small contribution to what has now been achieved.

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Written by physicsgg

July 8, 2012 at 11:23 am