Most Wanted Particle is an insider’s tale of the hunt for the Higgs boson, the field which imparts mass to, well, nearly everything. Written by Jon Butterworth —- a physicist working with the ATLAS team at the Large Hadron Collider —- the book documents the construction of the Large Hadron Collider, the catastrophe after it was first turned on, and the global excitement as evidence for the Higgs boson grew incontrovertible.
Most Wanted Particle has already received glowing praise from the likes of Brian Cox and even Peter Higgs —- for whom the boson is named -— and I’m sure that several physicists reading this site already have the book on their ‘to read’ list. But what about the rest of us? As a biology PhD whose last physics class was about 15 years ago, I decided to see if the book was accessible enough for your average science geek.
Find out how you can win a copy of this book, below.
First and only warning: the book discusses some very fundamental physics, and if you’re afraid to learn about topics like quarks, gluons, and hadronic jets, then this book will be tough going for you (all three of these are introduced on page 22, for instance). This complexity should be largely expected given the subject matter of the book; the alternative would be like a WW2 book that didn’t mention Normandy. So if learning some jargon scares you, you’d best stick to reading the news headlines from CERN.
With that caveat out of the way, Butterworth is a stellar writer and teacher, and he employs a number of tricks to make Most Wanted Particle extremely readable. First of all, equations are largely absent—they are described rather than displayed. (More kudos are due for making it over halfway through the book before the first Feynman diagram appears). Second is Butterworth’s impressive facility with analogy: often, even if you are struggling with the specifics of a concept, you will be able to grasp the broad brush strokes, and that’s enough to follow along with the tale.
Finally, there is the journalistic style. The book is written as a passionate first-person account, and the main narrative is pleasingly interrupted by diversions. It’s not uncommon to have a dense description of, say, super symmetry, broken up by a blog-like chapter discussing an international trip to a conference. (Other topics include meeting etiquette and ‘taking things offline’; what makes a good acronym; and a particularly memorable drunken night for the author and friends in Hamburg.)
Do you have friends who are scientists? If so, you will feel at home reading this book, and it took me a while to understand why. It’s because the general impression that I get from this book is very similar to taking a scientist friend to the pub, and having them describe their work to you over a beer. Sometimes you’ll get a little lost in the more thorny parts of the science; often you’ll get carried off by a tangent; but overall you’ll just enjoy a rollicking good tale, told by an intelligent storyteller.
This book comes highly recommended!
Most Wanted Particle is published by The Experiment Publishing. Find out more about the book here.
Thanks to The Experiment, Universe Today has one copy of this book to give away to our readers. The publisher has specified that for this contest, winners need to be from the US or Canada.
In order to be entered into the giveaway drawing, just put your email address into the box at the bottom of this post (where it says “Enter the Giveaway”) before Monday, April 13, 2015. We’ll send you a confirmation email, so you’ll need to click that to be entered into the drawing. If you’ve entered our giveaways before you should also receive an email with a link on how to enter.
The world’s most powerful particle collider is waking up from a well-earned rest. After roughly two years of heavy maintenance, scientists have nearly doubled the power of the Large Hadron Collider (LHC) in preparation for its next run. Now, it’s being cooled to just 1.9 degrees above absolute zero.
“We have unfinished business with understanding the universe,” said Tara Shears from the University of Liverpool in a news release. Shears and other LHC physicists will work to better understand the Higgs Boson and hopefully unravel some of the secrets of supersymmetry and dark matter.
On February 11, 2013 the LHC shut down for roughly two years. The break, known as LS1 for “long stop one,” was needed to correct several flaws in the original design of the collider.
The LHC’s first run got off to a rough start in 2008. Shortly after it was fired up, a single electrical connection triggered an explosion, damaging an entire sector (one-eighth) of the accelerator. To protect the accelerator from further disaster, scientists decided to run it at half power until all 10,000 copper connections could be repaired.
So over the last two years, scientists have worked around the clock to rework every single connection in the accelerator.
Now that the step (along with many others) is complete, the collider will operate at almost double its previous power. This was tested early last week, when scientists powered up the magnets of one sector to the level needed to reach the high energy expected in its second run.
With such a powerful new tool, scientists will look for deviations from their initial detection of the Higgs boson, potentially revealing a deeper level of physics that goes well beyond the Standard Model of particle physics.
Many theorists have turned to supersymmetry — the idea that for every known fundamental particle there exists a “supersymmetric” partner particle. If true, the enhanced LHC could be powerful enough to create supersymmetric particles themselves or prove their existence in subtler ways.
“The higher energy and more frequent proton collisions in Run 2 will allow us to investigate the Higgs particle in much more detail,” said Victoria Martin from Edinburgh University. “Higher energy may also allow the mysterious “dark matter” observed in galaxies to be made and studied in the lab for the first time.”
It’s possible that the Higgs could interact with — or even decay into — dark matter particles. If the latter occurs, then the dark matter particles would fly out of the LHC without ever being detected. But their absence would be evident.
So stay turned because these issues might be resolved in the spring of 2015 when the particle accelerator roars back to life.
This is the signature of one of 100s of trillions of particle collisions detected at the Large Hadron Collider. The combined analysis lead to the discovery of the Higgs Boson. This article describes one team in dissension with the results. (Photo Credit: CERN)
At the Large Hadron Collider (LHC) in Europe, faster is better. Faster means more powerful particle collisions and looking deeper into the makeup of matter. However, other researchers are proclaiming not so fast. LHC may not have discovered the Higgs Boson, the boson that imparts mass to everything, the god particle as some have called it. While the Higgs Boson discovery in 2012 culminated with the awarding in December 2013 of the Nobel Prize to Peter Higgs and François Englert, a team of researchers has raised these doubts about the Higgs Boson in their paper published in the journal Physical Review D.
The discourse is similar to what unfolded in the last year with the detection of light from the beginning of time that signified the Inflation epoch of the Universe. Researchers looking into the depths of the Universe and the inner depths of subatomic particles are searching for signals at the edge of detectability, just above the noise level and in proximity to the signals from other sources. For the BICEP2 telescope observations (previous U.T. articles), its pretty much back to the drawing board but the Higgs Boson (previous U.T. articles) doubts are definitely challenging but needing more solid evidence. In human affairs, if the Higgs Boson was not detected by the LHC, what does one do with an awarded Nobel Prize?
Cross-section of the Large Hadron Collider where its detectors are placed and collisions occur. LHC is as much as 175 meters (574 ft) below ground on the Franco-Swiss border near Geneva, Switzerland. The accelerator ring is 27 km (17 miles) in circumference. (Photo Credit: CERN)
The present challenge to the Higgs Boson is not new and is not just a problem of detectability and acuity of the sensors as is the case with BICEP2 data. The Planck space telescope revealed that light radiated from dust combined with the magnetic field in our Milky Way galaxy could explain the signal detected by BICEP2 that researchers proclaimed as the primordial signature of the Inflation period. The Higgs Boson particle is actually a prediction of the theory proposed by Peter Higgs and several others beginning in the early 1960s. It is a predicted particle from gauge theory developed by Higgs, Englert and others, at the heart of the Standard Model.
This recent paper is from a team of researchers from Denmark, Belgium and the United Kingdom led by Dr. Mads Toudal Frandsen. Their study entitled, “Technicolor Higgs boson in the light of LHC data” discusses how their supported theory predicts Technicolor quarks through a range of energies detectable at LHC and that one in particular is within the uncertainty level of the data point declared to be the Higgs Boson. There are variants of Technicolor Theory (TC) and the research paper compares in detail the field theory behind the Standard Model Higgs and the TC Higgs (their version of the Higgs boson). Their conclusion is that a TC Higgs is predicted by Technicolor Theory that is consistent with expected physical properties, is low mass and has an energy level – 125 GeV – indistinguishable from the resonance now considered to be the Standard Model Higgs. Theirs is a composite particle and it does not impart mass upon everything.
So you say – hold on! What is a Technicolor in jargon of particle physics? To answer this you would want to talk to a plumber from South Bronx, New York – Dr. Leonard Susskind. Though no longer a plumber, Susskind first proposed Technicolor to describe the breaking of symmetry in gauge theories that are part of the Standard Model. Susskind and other physicists from the 1970s considered it unsatisfactory that many arbitrary parameters were needed to complete the Gauge theory used in the Standard Model (involving the Higgs Scalar and Higgs Field). The parameters consequently defined the mass of elementary particles and other properties. These parameters were being assigned and not calculated and that was not acceptable to Susskind, ‘t Hooft, Veltmann and others. The solution involved the concept of Technicolor which provided a “natural” means of describing the breakdown of symmetry in the gauge theories that makeup the Standard Model.
Technicolor in particle physics shares one simple thing in common with Technicolor that dominated the early color film industry – the term composite in creating color or particles.
Dr. Leonard Susskind, a leading developer of the Theory of Technicolor (left) and Nobel Prize winner Dr. Peter Higgs who proposed the existence of a particle that imparts mass to all matter – the Higgs Boson (right). (Photo Credit: University of Stanford, CERN)
If the theory surrounding Technicolor is correct, then there should be many techni-quark and techni-Higgs particles to be found with the LHC or a more powerful next generation accelerator; a veritable zoo of particles besides just the Higgs Boson. The theory also means that these ‘elementary’ particles are composites of smaller particles and that another force of nature would be needed to bind them. And this new paper by Belyaev, Brown, Froadi and Frandsen claims that one specific techni-quark particle has a resonance (detection point) that is within the uncertainty of measurements for the Higgs Boson. In other words, the Higgs Boson might not be “the god particle” but rather a Technicolor Quark particle comprised of smaller more fundamental particles and another force binding them.
This paper by Belyaev, Brown, Froadi and Frandsen is a clear reminder that the Standard Model is unsettled and that even the discovery of the Higgs Boson is not 100% certain. In the last year, more sensitive sensors have been integrated into CERN’s LHC which will help refute this challenge to Higgs theory – Higgs Scalar and Field, the Higgs Boson or may reveal the signatures of Technicolor particles. Better detectors may resolve the difference between the energy level of the Technicolor quark and the Higgs Boson. LHC researchers were quick to state that their work moves on beyond discovery of the Higgs Boson. Also, their work could actually disprove that they found the Higgs Boson.
Contacting the co-investigator Dr. Alexander Belyaev, the question was raised – will the recent upgrades to CERN accelerator provide the precision needed to differentiate a technie-Quark from the Higg’s particle?
“There is no guarantee of course” Dr. Belyaev responded to Universe Today, “but upgrade of LHC will definitely provide much better potential to discover other particles associated with theory of Technicolor, such as heavy Techni-mesons or Techni-baryons.”
Resolving the doubts and choosing the right additions to the Standard Model does depend on better detectors, more observations and collisions at higher energies. Presently, the LHC is down to increase collision energies from 8 TeV to 13 TeV. Among the observations at the LHC, Super-symmetry has not fared well and the observations including the Higgs Boson discovery has supported the Standard Model. The weakness of the Standard Model of particle physics is that it does not explain the gravitational force of nature whereas Super-symmetry can. The theory of Technicolor maintains strong supporters as this latest paper shows and it leaves some doubt that the Higgs Boson was actually detected. Ultimately another more powerful next-generation particle accelerator may be needed.
In a previous Universe Today story, the question was raised – is the Standard Model a Rube Goldberg Device? Most theorists would say ‘no’ but it is unlikely to reach the status of the ‘theory of everything’ (Illustration Credit: R.Goldberg- the toothpaste dispenser, variant T.Reyes)
For Higgs and Englert, the reversal of the discovery is by no means the ruination of a life’s work or would be the dismissal of a Nobel Prize. The theoretical work of the physicists have long been recognized by previous awards. The Standard Model as, at least, a partial solution of the theory of everything is like a jig-saw puzzle. Piece by piece is how it is being developed but not without missteps. Furthermore, the pieces added to the Standard Model can be like a house of cards and require replacing a larger solution with a wholly other one. This could be the case of Higgs and Technicolor.
At times like children somewhat determined, physicists thrust a solution into the unfolding puzzle that seems to fit but ultimately has to be retracted. The present discourse does not yet warrant a retraction. Elegance and simplicity is the ultimate characteristics sought in theoretical solutions. Particle physicists also use the term Naturalnesswhen describing the concerns with gauge theory parameters. The solutions – the pieces – of the puzzle created by Peter Higgs and François Englert have spearheaded and encouraged further work which will achieve a sounder Standard Model but few if any claim that it will emerge as the theory of everything.
This is the signature of one of 100s of trillions of particle collisions detected at the Large Hadron Collider. The combined analysis lead to the discovery of the Higgs Boson. This article describes one team in dissension with the results. (Photo Credit: CERN)
That was fast! Just one year after a Higgs Boson-like particle was found at the Large Hadron Collider, the two physicists who first proposed its existence have received the Nobel Prize in Physics for their work. François Englert (of the former Free University of Brussels in Belgium) and Peter W. Higgs (at the University of Edinburgh in the United Kingdom) received the prize officially this morning (Oct. 8.)
The Brout-Englert-Higgs (BEH) mechanism was first described in two independent papers by these physicists in 1964, and is believed to be responsible for the amount of matter a particle contains. Higgs himself said this mechanism would be visible in a massive boson (or subatomic particle), later called the Higgs boson. Check out more information on what the particle means at this past Universe Today article by editor Nancy Atikinson.
“The awarded theory is a central part of the Standard Model of particle physics that describes how the world is constructed. According to the Standard Model, everything, from flowers and people to stars and planets, consists of just a few building blocks: matter particles. These particles are governed by forces mediated by force particles that make sure everything works as it should,” the Royal Swedish Academy of Sciences said in a statement.
The Standard Model describes the interactions of fundamental particles. The W boson, the carrier of the electroweak force, has a mass that is fundamentally relevant for many predictions, from the energy emitted by our sun to the mass of the elusive Higgs boson. Credit: Fermilab
“The entire Standard Model also rests on the existence of a special kind of particle: the Higgs particle. This particle originates from an invisible field that fills up all space. Even when the universe seems empty this field is there. Without it, we would not exist, because it is from contact with the field that particles acquire mass. The theory proposed by Englert and Higgs describes this process.”
A very thrilled CERN (the European Organization for Nuclear Research) noted that the Standard Model theory has been “remarkably successful”, and passed several key tests before the particle was unveiled last year in ATLAS and CMS experiments at the Large Hadron Collider.
Dark matter in the Bullet Cluster. Otherwise invisible to telescopic views, the dark matter was mapped by observations of gravitational lensing of background galaxies. Credit: X-ray: NASA/CXC/CfA/ M.Markevitch et al.; Lensing Map: NASA/STScI; ESO WFI; Magellan/U.Arizona/ D.Clowe et al. Optical: NASA/STScI; Magellan/U.Arizona/D.Clowe et al.;
“The discovery of the Higgs boson at CERN last year, which validates the Brout-Englert-Higgs mechanism, marks the culmination of decades of intellectual effort by many people around the world,” stated CERN director General Rolf Heuer.
CERN added that the discovery last year was exciting, but the Higgs boson only explains only the matter that we can see. CERN is among the organizations on the hunt for dark matter and energy, forms that can’t be sensed with conventional observatories but can be seen through their effects — such as gravitational lensing.
If you’re still scratching your head, trying to figure out all the Higgs Boson news, the great folks from MinutePhysics have put together a new video to explain it all. However, since this is all a little complicated, it’s going to take more than one minute. Parts 2 and 3 are on their way!
This is the signature of one of 100s of trillions of particle collisions detected at the Large Hadron Collider. The combined analysis lead to the discovery of the Higgs Boson. This article describes one team in dissension with the results. (Photo Credit: CERN)
Physicists working at the Large Hadron Collider (LHC) have announced the discovery of what they called a “Higgs-like boson” — a particle that resembles the long sought-after Higgs.
“We have reached a milestone in our understanding of nature,” CERN director general Rolf Heuer told scientists and media at a conference near Geneva on July 4, 2012. “The discovery of a particle consistent with the Higgs boson opens the way to more detailed studies, requiring larger statistics, which will pin down the new particle’s properties, and is likely to shed light on other mysteries of our universe.”
Two experiments, ATLAS and CMS, presented their preliminary results, and observed a new particle in the mass region around 125-126 GeV, the expected mass range for the Higgs Boson. The results are based on data collected in 2011 and 2012, with the 2012 data still under analysis. The official results will be published later this month and CERN said a more complete picture of today’s observations will emerge later this year after the LHC provides the experiments with more data.
“We observe in our data clear signs of a new particle, at the level of 5 sigma, in the mass region around 126 GeV. The outstanding performance of the LHC and ATLAS and the huge efforts of many people have brought us to this exciting stage,” said ATLAS experiment spokesperson Fabiola Gianotti, “but a little more time is needed to prepare these results for publication.”
The discovery of the Higgs is big, in that it is the last undiscovered piece of the Standard Model that describes the fundamental make-up of the universe.
Scientists believe that the Higgs boson, named for Scottish physicist Peter Higgs, who first theorized its existence in 1964, is responsible for particle mass, the amount of matter in a particle. According to the theory, a particle acquires mass through its interaction with the Higgs field, which is believed to pervade all of space and has been compared to molasses that sticks to any particle rolling through it.
And so, in theory, the Higgs would be responsible for how particles come together to form matter, and without it, the universe would have remained a formless miss-mash of particles shooting around at the speed of light.
“It’s hard not to get excited by these results,” said CERN Research Director Sergio Bertolucci. “We stated last year that in 2012 we would either find a new Higgs-like particle or exclude the existence of the Standard Model Higgs. With all the necessary caution, it looks to me that we are at a branching point: the observation of this new particle indicates the path for the future towards a more detailed understanding of what we’re seeing in the data.”
A CERN press release says that the next step will be to determine the precise nature of the particle and its significance for our understanding of the universe.
Are its properties as expected for the long-sought Higgs boson, the final missing ingredient in the Standard Model of particle physics? Or is it something more exotic? The Standard Model describes the fundamental particles from which we, and every visible thing in the universe, are made, and the forces acting between them. All the matter that we can see, however, appears to be no more than about 4% of the total. A more exotic version of the Higgs particle could be a bridge to understanding the 96% of the universe that remains obscure. – CERN press release
“We have reached a milestone in our understanding of nature,” said CERN Director General Rolf Heuer. “The discovery of a particle consistent with the Higgs boson opens the way to more detailed studies, requiring larger statistics, which will pin down the new particle’s properties, and is likely to shed light on other mysteries of our universe.”
Positive identification of the new particle’s characteristics will take more time and more experiments. But the scientists feel that whatever form the Higgs particle takes, our knowledge of the fundamental structure of matter is about to take a major step forward.
Lead image caption: Event recorded with the CMS detector in 2012 at a proton-proton centre of mass energy of 8 TeV. The event shows characteristics expected from the decay of the SM Higgs boson to a pair of photons (dashed yellow lines and green towers). The event could also be due to known standard model background processes. Credit: CERN
Scientists gather as the ATLAS and CMS experiments present the status of their searches for the Standard Model Higgs boson. Credit: CERN
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With “freshly squeezed” plots from the latest data garnered by two particle physics experiments, teams of scientists from the Large Hadron Collider at CERN, the European Center for Nuclear Research, said Tuesday they had recorded “tantalizing hints” of the elusive subatomic particle known as the Higgs Boson, but cannot conclusively say it exists … yet. However, they predict that 2012 collider runs should bring enough data to make the determination.
“The very fact that we are able to show the results of very sophisticated analysis just one month after the last bit of data we used has been recorded is very reassuring,” Dr. Greg Landsberg, physics coordinator for the Compact Muon Solenoid (CMS) detector at the LHC told Universe Today. “It tells you how quick the turnaround time is. This is truly unprecedented in the history of particle physics, with such large and complex experiments producing so much data, and it’s very exciting.”
For now, the main conclusion of over 6,000 scientists on the combined teams from CMS and the ATLAS particle detectors is that they were able to constrain the mass range of the Standard Model Higgs boson — if it exists — to be in the range of 116-130 GeV by the ATLAS experiment, and 115-127 GeV by CMS.
The Standard Model is the theory that explains the interactions of subatomic particles – which describes ordinary matter that the Universe is made of — and on the whole works very well. But it doesn’t explain why some particles have mass and others don’t, and it also doesn’t describe the 96% of the Universe that is invisible.
In 1964, physicist Peter Higgs and colleagues proposed the existence of a mysterious energy field that interacts with some subatomic particles more than others, resulting in varying values for particle mass. That field is known as the Higgs field, and the Higgs Boson is the smallest particle of the Higgs field. But the Higgs Boson hasn’t been discovered yet, and one of the main reasons the LHC was built was to try to find it.
To look for these tiny particles, the LHC smashes high-energy protons together, converting some energy to mass. This produces a spray of particles which are picked up by the detectors. However, the discovery of the Higgs relies on observing the particles these protons decay into rather than the Higgs itself. If they do exist, they are very short lived and can decay in many different ways. The problem is that many other processes can also produce the same results.
How can scientists tell the difference? A short answer is that if they can figure out all the other things that can produce a Higgs-like signal and the typical frequency at which they will occur, then if they see more of these signals than current theories suggest, that gives them a place to look for the Higgs.
The experiments have seen excesses in similar ranges. And as the CERN press release noted, “Taken individually, none of these excesses is any more statistically significant than rolling a die and coming up with two sixes in a row. What is interesting is that there are multiple independent measurements pointing to the region of 124 to 126 GeV.”
“This is very promising,” said Landsberg, who is also a professor at Brown University. “This shows that both experiments understand what is going on with their detectors very, very well. Both calibrations saw excesses at low masses. But unfortunately the nature of our process is statistical and statistics is known to play funny tricks once in a while. So we don’t really know — we don’t have enough evidence to know — if what we saw is a glimpse of the Higgs Boson or these are just statistical fluctuations of the Standand Model process which mimic the same type of signatures as would come if the Higgs Boson is produced.”
Landsberg said the only way to cope with statistics is to get more data, and the scientists need to increase the size of the data samples considerably in order to definitely answer the question on whether the Higgs Boson exists at the mass of 125 GeV or any mass range which hasn’t been excluded yet.
The good news is that loads of data are coming in 2012.
“We hope to quadruple the data sample collected this year,” Landsberg said. “And that should give us enough statistical confidence to essentially solve this puzzle and tell the world whether we saw the first glimpses of the Higgs Boson. As the team showed today, we will keep increasing until we reach a level of statistical significance which is considered to be sufficient for discovery in our field.”
Landsberg said that within this small range, there is not much room for the Higgs to hide. “This is very exciting, and it tells you that we are almost there. We have enough sensitivity and beautiful detectors; we need just a little bit more time and a little more data. I am very hopeful we should be able to say something definitive by sometime next year.”
So the suspense is building and 2012 could be the year of the Higgs.
Brian Cox at CERN with Kevin Eldon and Simon Munnery. Photo by Gia Milinovich, courtesy Brian Cox
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At two separate conferences in July, particle physicists announced some provoking news about the Higgs boson, and while the Higgs has not yet been found, physicists are continuing to zero in on the elusive particle. Universe Today had the chance to talk with Professor Brian Cox about these latest findings, and he says that within six to twelve months, physicists should be able to make a definite statement about the existence of the Higgs particle. Cox is the Chair in Particle Physics at the University of Manchester, and works on the ATLAS experiment (A Toroidal LHC ApparatuS) at the Large Hadron Collider at CERN. But he’s also active in the popularization of science, specifically with his new television series and companion book, Wonders of the Universe, a follow up to the 2010 Peabody Award-winning series, Wonders of the Solar System.
Universe Today readers will have a chance to win a copy of the book, so stay tuned for more information on that. But today, enjoy the first of a three-part interview with Cox:
Universe Today: Can you tell us about your work with ATLAS and its potential for finding things like extra dimensions, the unification of forces or dark matter?
Brian Cox, during the filming of one of his television series. Image courtesy Brian Cox.
Brian Cox: The big question is the origin and mass of the universe. It is very, very important because it is not an end in itself. It is a fundamental part of Quantum Field Theory, which is our theory of three of the four forces of nature. So if you ask the question on the most basic level of how does the universe work, there are only two pillars of our understanding at the moment. There is Einstein’s Theory of General Relatively, which deals with gravity — the weakest force in the Universe that deals with the shape of space and time and all those things. But everything else – electromagnetism, the way the atomic nuclei works, the way molecules work, chemistry, all that – everything else is what’s called a Quantum Field Theory. Embedded in that is called the Standard Model of particle physics. And embedded in that is this mechanism for generating mass, and it’s just so fundamental. It’s not just kind of an interesting add-on, it’s right in the heart of the way the theory works.
So, understanding whether our current picture of the Universe is right — and if there is this thing called the Higgs mechanism or whether there is something else going on — is critical to our progress because it is built into that picture. There are hints in the data recently that maybe that mechanism is right. We have to be careful. It’s not a very scientific thing to say that we have hints. We have these thresholds for scientific discovery, and we have them for a reason, because you get these statistical flukes that appear in the data and when you get more data they go away again.
The statement from CERN now is that if they turn out to be more than just fluctuations, really, within six months we should be able to make some definite statement about the existence of the Higgs particle.
I think it is very important to emphasize that this is not just a lot of particle physicists looking for particles because that’s their job. It is the fundamental part of our understanding of three of the four forces of nature.
Brian Cox at Fermilab. Photo by Paul Olding.
UT : So these very interesting results from CERN and the Tevatron at Fermilab giving us hints about the Higgs, could you can talk little bit more about that and your take on the latest findings?
COX: The latest results were published in a set of conferences a few weeks ago and they are just under what is called the Three Sigma level. That is the way of assessing how significant the results are. The thing about all quantum theory and particle physics in general, is it is all statistical. If you do this a thousand times, then three times this should happen, and eight times that should happen. So it’s all statistics. As you know if you toss a coin, it can come up heads ten times, there is a probability for that to happen. It doesn’t mean the coin is weighted or there’s something wrong with it. That’s just how statistics is.
So there are intriguing hints that they have found something interesting. Both experiments at the Large Hadron Collider, the ATLAS and the Compact Muon Solenoid (CMS) recently reported “excess events” where there were more events than would be expected if the Higgs does not exist. It is about the right mass: we think the Higgs particle should be somewhere between about 120 and 150 gigaelectron volts [GeV—a unit of energy that is also a unit of mass, via E = mc2, where the speed of light, c, is set to a value of one] which is the expected mass range of the Higgs. These hints are around 140, so that’s good, it’s where it should be, and it is behaving in the way that it is predicted to by the theory. The theory also predicts how it should decay away, and what the probability should be, so all the data is that this is consistent with the so-called standard model Higgs.
But so far, these events are not consistently significant enough to make the call. It is important that the Tevatron has glimpsed it as well, but that has even a lower significance because that was low energy and not as many collisions there. So you’ve got to be scientific about things. There is a reason we have these barriers. These thresholds are to be cleared to claim discoveries. And we haven’t cleared it yet.
But it is fascinating. It’s the first time one of these rumors have been, you know, not just nonsense. It really is a genuine piece of exciting physics. But you have to be scientific about these things. It’s not that we know it is there and we’re just not going to announce it yet. It’s the statistics aren’t here yet to claim the discovery.
Brian Cox, while filming a BBC series in the Sahara. Image courtesy Brian Cox
UT : Well, my next question was going to be, what happens next? But maybe you can’t really answer that because all you can do is keep doing the research!
COX: The thing about the Higgs, it is so fundamentally embedded in quantum theory. You’ve got to explore it because it is one thing to see a hint of a new particle, but it’s another thing to understand how that particle behaves. There are lots of different ways the Higgs particles can behave and there are lots of different mechanisms.
There is a very popular theory called supersymmetry which also would explain dark matter, one of the great mysteries in astrophysics. There seems to be a lot of extra stuff in the Universe that is not behaving the way that particles of matter that we know of behave, and with five times more “stuff” as what makes up everything we can see in the Universe. We can’t see dark matter, but we see its gravitational influence. There are theories where we have a very strong candidate for that — a new kind of particle called a supersymmetry particles. There are five Higgs particles in them rather than one. So the next question is, if that is a Higgs-like particle that we’ve discovered, then what is it? How does it behave? How does it talk to the other particles?
And then there are a huge amount of questions. The Higgs theory as it is now doesn’t explain why the particles have the masses they do. It doesn’t explain why the top quark, which is the heaviest of the fundamental particles, is something like 180 times heavier than the proton. It’s a tiny point-like thing with no size but it’s 180 times the mass of a proton! That is heavier than some of the heaviest atomic nuclei!
Why? We don’t know.
I think it is correct to say there is a door that needs to be opened that has been closed in our understanding of the Universe for decades. It is so fundamental that we’ve got to open it before we can start answering these further questions, which are equally intriguing but we need this answered first.
UT: When we do get some of these questions answered, how is that going to change our outlook and the way that we do things, or perhaps the way YOU do things, anyway! Maybe not us regular folks…
COX: Well, I think it will – because this is part of THE fundamental theory of the forces of nature. So quantum theory in the past has given us an understanding, for example, of the way semiconductors work, and it underpins our understanding of modern technology, and the way chemistry works, the way that biological systems work – it’s all there. This is the theory that describes it all. I think having a radical shift and deepening in understanding of the basic laws of nature will change the way that physics proceeds in 21st century, without a doubt. It is that fundamental. So, who knows? At every paradigm shift in science, you never really could predict what it was going to do; but the history of science tells you that it did something quite remarkable.
There is a famous quote by Alexander Fleming, who discovered penicillin, who said that when he woke up on a certain September morning of 1928, he certainly didn’t expect to revolutionize modern medicine by discovering the world’s first antibiotic. He said that in hindsight, but he just discovered some mold, basically, but there it was.
But it was fundamental and that is the thing to emphasize.
Some of our theories, you look at them and wonder how we worked them! The answer is mathematically, the same way that Einstein came up with General Relativity, with mathematical predictions. It is remarkable we’ve been able to predict something so fundamental about the way that empty space behaves. We might turn out to be right.
Tomorrow: Part 2: The space exploration and hopes for the future
The Large Hadron Collider at CERN. Credit: CERN/LHC
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When the media talks about the “god particle”, they’re really talking about a theoretical particle in physics known as the higgs boson. If reality matches the predictions made by theoretical physics, the higgs boson is the particle that gives objects mass. It explains why objects at rest tend to stay at rest and objects in motion tend to stay in motion.
One of the primary goals of the Large Hadron Collider in Switzerland is to search for the so called “god particle”. When it finally gets running, the Large Hadron Collider, or LHC, will run beams of protons around a 27 kilometer circle, slamming them together at close to the speed of light. All the kinetic energy of the protons is instantly frozen out as mass in a shower of particles. Remember Einstein’s famous E=mc2 formula? Well, you can reconfigure the equation to be m = E/c2.
The higgs boson is thought to be a very heavy particle, and so it takes a lot of energy in the collider to create particles this massive. When the LHC starts running, it will collide protons at higher and higher energies, searching for the higgs boson. If it is found, it will confirm a theorized class of particles predicted by the theory of supersymmetry. And even if the higgs boson isn’t found, it will help disprove the theory. Either way, physicists win.
The term “god particle” was coined by physicist Leon Lederman, the 1988 Nobel prize winner in physics and the director of Fermilab. He even wrote a book called the “God Particle”, where he defended the use of the term.
