==== John Ellis, theoretical physicist, answers the question "Are we close to discovering the Higgs Boson and why is it so difficult to find it?" in preparation of the Press Conference following the scientific seminar announcing results of the searches for the Higgs boson on July 4 2012. For more details:
=== Fermilab scientist Don Lincoln describes the concept of how the search for the Higgs boson is accomplished. The latest data is revealed! Several large experimental groups are hot on the trail of this elusive subatomic particle which is thought to explain the origins of particle mass. You can try the
Particle discovery is game changer for understanding the universe
Whether discovery is a Higgs or not, particle could explain dark matter, anti-matter, how universe began
By Sharon Gaudin
July 5, 2012 04:52 PM ET
Computerworld - Physicists trying to understand dark matter, anti-matter and the origin of the universe say the key to these great mysteries may lie with the discovery of a sub-atomic particle, whether it's the elusive Higgs boson or not.
"This is a keystone," said A.J. Stewart Smith, physicist and dean for research at Princeton University. "This will give us more of an understanding of why everything exists ... This is huge in magnitude and scope."
On Wednesday, scientists at CERN, the European Organization for Nuclear Research, announced the discovery of a new particle, and early indications point to it being the Higgs boson, which has such great mystery and scientific importance that it has been dubbed the God particle.
The Higgs boson is a theoretical sub-atomic particle that is thought to be the reason that everything has mass. Basically, without mass -- without the Higgs boson -- there would be no nuclear structure to anything, so there would be no trees, no people, no plants, no stars.
Professor Peter Higgs, a British physicist, first suggested the existence of the mass-causing particle in the 1960s. As it became a cornerstone of physics theory, the search to find the particle was on.
While CERN scientists would not go so far as to say definitively that the particle is the Higgs boson, first indications point in that direction.
For instance, Smith noted that the particle's mass is what scientists expected for a Higgs. The way it decays and what it decays into also go along with what would be expected for a Higgs boson.
However, these are initial tests. Many more will be required to determine if the discovery is a Higgs boson.
Antonio Boveia, a physicist at the University of Chicago and part of the CERN team, said more data is needed for study but that information will come from more particle collisions at the Large Hadron Collider, the largest particle collider in the world.
The collider is scheduled to run for the rest of this year but then will be shut down for two years for a power upgrade. If scientists don't have enough data by December to prove or disprove that the particle is a Higgs, they'll have to wait two years.
"We'll have some degree of confidence by the end of the year, but it's an open question as to if we'll have enough," said Boveia, who called finding the particle the most exciting discovery in 30 years. "But probably not."
However, the fact that scientists have discovered a new particle, whether it ends up being the Higgs boson or not, will be a game changer in the world of physics, and is likely to change the way we understand the world around us. Smith said the most exciting outcome would be if the particle is not the Higgs.
"If it isn't the Higgs, what in God's name is it?" he said. "It would change our thinking in a pretty profound way ... It will all depend on what it is. It's hard to even imagine."
Boveia said physicists use a theory called the standard model for describing the basic building blocks of nature. Essentially, it's a model of how the universe is made and held together. If the recently discovered particle isn't a Higgs, and is instead a new particle, then that standard model is incomplete, he explained.
"If it's a brand new particle, it will be extremely exciting," Boveia added. "We'll have to find a new way to talk about nature."
But if the particle is a Higgs boson, then scientists will know that a key piece of the way the fundamentals of the universe are understood is correct.
However, the discovery will move scientists beyond affirming what they've already believed.
Physicists and astronomers still have questions without a real path to finding the answers. What happened to anti-matter? What is dark matter? What is dark energy? What was going on when the universe was first formed?
If the particle is a Higgs boson, and if scientists can begin to study and understand it, it could lead to answers to some of these great mysteries, Smith said.
"You can imagine the calculations it takes to understand what was going on at the beginning of the universe," he added. "The role of Higgs is absolutely fundamental. What caused particles to have mass and to join with each other? The universe would have no structure without Higgs. This will immensely accelerate our knowledge of the universe."
For instance, at the beginning of the universe, there was an equal number of particles and anti-particles - matter and anti-matter. These particles had opposite electric charges, Smith said.
It's believed that when matter and anti-matter collided, they turned back into energy. But if there is still matter in the world, what happened to those matter-busting collisions? While the anti-matter has simply seemed to disappear, where did it go? What process left us with matter but not anti-matter?
"Higgs could be connected to this imbalance. Nobody knows," Smith said. "If there are Higgs to be found, there could be possibilities [for scientists to understand this.]"
Sharon Gaudin covers the Internet and Web 2.0, emerging technologies, and desktop and laptop chips for Computerworld. Follow Sharon on Twitter at @sgaudin or subscribe to Sharon's RSS feed . Her e-mail address is [email protected].
The God Particle by Jeff Danner - Common Science , posted Jul 8 2012 10:03PM
July 4th, 2012, was a significant day in the history of science. In a news conference in Geneva Switzerland, physicists at the Large Hadron Collider โ a 16 mile long particle accelerator where matter is smashed together in an attempt to recreate conditions which existed fractions of a second after the Big Bang - announced that, after a 30+ year search, they have confirmed the existence of the Higgs boson. This is a really big deal. As I will explain, there is a reason the Higgs boson has acquired the nickname the โGod Particleโ. As usual, the mainstream media coverage on this dumbs down the science when reporting this story, assuming that the reader cannot possibly understand. This is just the type of gap in news coverage that I try to fill here in Common Scienceยฎ. So fasten your seat belts and return your tray tables to their full, upright, and locked positions as we embark on a journey into particle physics.
To understand why the discovery of the Higgs boson is so important, we need to start with a review of the structure of matter and a summary of the Standard Model of physics. Early on in high school chemistry you were taught that atoms were made up of protons, neutrons, and electrons. Then most of the remainder of the course focused on the interactions of atoms. However, I expect that at least part of one of the lectures did mention that protons and neutrons are made up of even smaller particles called quarks, whose existence was first proposed in 1964. The concept of quarks gave rise to the development of the Standard Model (SM) of physics.
The SM attempts to explain the properties and interactions of all the elementary particles and fundamental forces in the universe. The four forces in the universe according to the SM are gravity, and the electromagnetic, strong, and weak interaction forces. Although everyone is familiar with the effects of gravity, its mechanism is still not fully understood. (For more detail see my earlier column โGravity, Still a Mysteryโ). The electromagnetic force controls interactions between atoms and molecules. As such, it is the driver of all of the phenomena you observe in daily life, including light, electricity, weather, and chemical reactions. The strong interaction force is what holds the protons and neutrons inside of the nucleus of an atom together and the weak interaction force is what causes some nuclei to break apart in the process known as nuclear decay (think nuclear power or an atom bomb.) (You may be thinking โHey it doesnโt make any sense that the weak interaction force can overcome the strong one to break apart a nucleus. I agree but I didnโt get to pick the names.)
The SM describes 12 elementary particles which make up all of matter. Six of these are quarks and six are leptons. Most people have heard of quarks. The six quarks are called up, down, charm, strange, top and bottom. Protons and neutrons are made up of combinations of up and down quarks. Charm, strange, top and bottom quarks are unstable and can only be created in very high energy situations like the big bang or in a particle accelerator. Leptons are much less familiar to the general public than quarks. I will not give a review of leptons here as it is not necessary for this column. You do know one of the six leptons, the electron. The other 5 are not stable.
The four fundamental forces act on the 12 elementary particles through force carrier particles known as bosons. For example, the strong force which holds nuclei together is mediated by the exchange of bosons which are rather appropriately named gluons. The electromagnetic force is mediated by the most familiar or the bosons, the photon (Many thanks to Star Trek for bringing this word into public consciousness with the โphoton torpedoโ). Photons are what make up electromagnetic radiation. You are familiar with some types of electromagnetic radiation such as light, ultraviolet rays and gamma radiation. For more on electromagnetic radiation see my earlier column, โIs your cell phone trying to kill you?โ The weak interaction force is controlled by the less charmingly named W and Z bosons. The boson for gravity, named the graviton, has yet to be observed.
Simply stated, the SM tell us that the universe is composed of 12 elementary particles which interact with one another in 4 ways through the exchange of force carrier particles know as bosons.
Now that we have the basics down we can move on to the elusive and amazing Higgs boson. In the 1960s, Professor Peter Higgs of the University of Edinburgh published several papers addressing a key gap in the Standard Model. It could not account for the fact that elementary particles had mass. As gaps in theories go, not having an explanation for mass was a doozy. Without mass, the Big Bang would have generated a uniform field of energy expanding throughout the universe. Such a universe would be featureless and lifeless.
To fill this gap, Higgs predicted the existence of a force exchange particle, later named for him, that imparts mass to quarks and leptons, allowing them to attract one another via gravity. Therefore, the action of the Higgs boson eventually led to the coalescence of sub-atomic particles into protons and neutrons, then atoms, then molecules, then solar systems, then planets and then, eventually, us. Hence the โGod Particleโ nickname. Higgs, who is alive and kicking, is purported to dislike the name as being a bit sensationalistic, keeping alive the stereotype that physicists need a better sense of marketing.
Physicists searched for the Higgs boson for four decades by smashing small pieces of matter together at extremely high energy. Their goal was to create conditions similar to those which existed a fraction of a second after the big bang. This is the moment when, according to the Standard Model, the Higgs boson came into existence and began its task of imparting mass to nearby quarks and leptons. Our ability to recreate these conditions in the Large Hadron Collider is an amazing feat and it helps to confirm our understanding of the origin of the universe.
I am glad to see that physics can still garner headlines in the days of reality TV and insipid political commercials. I think part of the interest comes from the realization that there is still much about the universe that we still donโt understand. Even with the remarkable achievement of finding the Higgs boson, we still canโt account for 90% of the mass in the universe. So there is still quite a bit of physics left to be done.
I hope that that Mr. Higgs enjoyed the announcement on Wednesday. Forty years is a long time to wait to be proved right.
Summary: The scientific community is cock-a-hoop over CERN's discovery of a something that looks like the Higgs boson. But why? And what does it help us understand?
By Lucy Sherriff for Qubits and Pieces | July 9, 2012 -- Updated 15:26 GMT (08:26 PDT)
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The Higgs boson โ or at least, a boson "consistent with" it - has been found. The question now is: why should we care?
Well, the Higgs boson is predicted by the Standard Model of particle physics. This model explains the physics of the atom and the nucleus. Lots of weird little zippy particles (quarks and Z particles, for instance) predicted by the model have been found, which made it seem reasonably reliable.
Scientists have identified the Higgs boson using the Large Hadron Collider at CERN. Image credit: CERNSo physicists would be very annoyed if something as big as the Higgs boson were to pull the rug out from under the whole thing by failing to exist.
Another reason for CERN's celebrations is that it was hard to find. That's because it is so big. For a particle.
Thanks to Einstein, we know that mass and energy are the same thing, and the Higgs is a very high-energy particle indeed. It was, in fact, lurking somewhere between 125GeV and 126GeV on the energy spectrum. Top quarks are very massive particles, clocking in at 172GeV โ around the same as an atom of Tungsten. By contrast, the humble photon has an energy of the order of a single electron volt, effectively having zero mass.
Large particles are unstable, decaying quickly into smaller particles. This means that any naturally occurring Higgs bosons would have decayed long, long ago, before there even were galaxies to be far, far away.
It also means that it is not the Higgs itself that physicists are looking for, but the products of its decay. In the case of the top quark, these smaller particles are mostly the bottom quark, but also the strange and down quarks. The Higgs boson should decay almost immediately into some combination of electrons and hadrons, and it is these energetic traces that scientists went looking for.
A very energetic explosion
To find something so big, particle physicists needed to make a very energetic explosion. So they built the Large Hadron Collider at CERN. This is a monumentally powerful particle accelerator, capable of creating the kinds of collisions between proton beams that might just produce a few stray Higgs bosons, which would then decay in a tell-tale way.
What does the Higgs boson do? Mostly, it provides evidence of the Higgs field. This was an idea put forward by Professor Peter Higgs to explain why matter has mass. Conceptually, it is like a sticky gluey jelly that permeates the whole of the universe. The strength of a particle's interaction with the Higgs field determines its mass.
All elementary particles are either bosons or fermions. A fermion is something like an electron, and is generally associated with matter. A boson, in general, is a force-carrying particle that mediates a field. (In my nuclear physics classes, fermions were described to me as being like tigers [I confess, I have forgotten why], while bosons were like cattle, always being in a field. Har har.) For example, photons are the force carriers that mediate the electromagnetic field.
So a Higgs boson is the force-carrying particle, or smallest excitation possible, of the Higgs field. Find it, and we prove the existence of the Higgs field, and thus the completeness (almost) of the standard model of physics. http://www.zdnet.com/the-higgs-boson-why-shou...-we-care-7000000462/
Pakistan shuns its only Nobel laureate - physicist linked to discovery of 'God particle'
ISLAMABAD: The pioneering work of Abdus Salam, Pakistan's only Nobel laureate, helped lead to the apparent discovery of the subatomic " God particle" last week. But the late physicist is no hero at home, where his name has been stricken from school textbooks.
Praise within Pakistan for Salam, who also guided the early stages of the country's nuclear program, faded decades ago as Muslim fundamentalists gained power. He belonged to the Ahmadi sect, which has been persecuted by the government and targeted by Taliban militants who view its members as heretics. http://articles.timesofindia.indiatimes.com/2...god-particle-ahmadis