The Large Hadron Collider: We’ve Definitely Found the Higgs Boson

higgs-boson1In July 2012, the CERN laboratory in Geneva, Switzerland made history when it discovered an elementary particle that behaved in a way that was consistent with the proposed Higgs boson – otherwise known as the “God Particle”. Now, some two years later, the people working the Large Hadron Collider have confirmed that what they observed was definitely the Higgs boson, the one predicted by the Standard Model of particle physics.

In the new study, published in Nature Physics, the CERN researchers indicated that the particle observed in 2012 researchers indeed decays into fermions – as predicted by the standard model of particle physics. It sits in the mass-energy region of 125 GeV, has no spin, and it can decay into a variety of lighter particles. This means that we can say with some certainty that the Higgs boson is the particle that gives other particles their mass – which is also predicted by the standard model.

CERN_higgsThis model, which is explained through quantum field theory  – itself an amalgam of quantum mechanics and Einstein’s special theory of relativity – claims that deep mathematical symmetries rule the interactions among all elementary particles. Until now, the decay modes discovered at CERN have been of a Higgs particle giving rise to two high-energy photons, or a Higgs going into two Z bosons or two W bosons.

But with the discovery of fermions, the researchers are now sure they have found the last holdout to the full and complete confirmation that the Standard Model is the correct one. As Marcus Klute of the CMS Collaboration said in a statement:

Our findings confirm the presence of the Standard Model Boson. Establishing a property of the Standard Model is big news itself.

CERN_LHCIt is certainly is big news for scientists, who can say with absolute certainty that our current conception for how particles interact and behave is not theoretical. But on the flip side, it also means we’re no closer to pushing beyond the Standard Model and into the realm of the unknown. One of the big shortfalls of the Standard Model is that it doesn’t account for gravity, dark energy and dark matter, and some other quirks that are essential to our understanding of the universe.

At present, one of the most popular theories for how these forces interact with the known aspects of our universe – i.e. electromagnetism, strong and nuclear forces – is supersymmetry.  This theory postulates that every Standard Model particle also has a superpartner that is incredibly heavy – thus accounting for the 23% of the universe that is apparently made up of dark matter. It is hoped that when the LHC turns back on in 2015 (pending upgrades) it will be able to discover these partners.

CERN_upgradeIf that doesn’t work, supersymmetry will probably have to wait for LHC’s planned successor. Known as the “Very Large Hadron Collider” (VHLC), this particle accelerator will measure some 96 km (60 mile) in length – four times as long as its predecessor. And with its proposed ability to smash protons together with a collision energy of 100 teraelectronvolts – 14 times the LHC’s current energy – it will hopefully have the power needed to answer the questions the discovery of the Higgs Boson has raised.

These will hopefully include whether or not supersymmetry holds up and how gravity interacts with the three other fundamental forces of the universe – a discovery which will finally resolve the seemingly irreconcilable theories of general relativity and quantum mechanics. At which point (and speaking entirely in metaphors) we will have gone from discovering the “God Particle” to potentially understanding the mind of God Himself.

I don’t think I’ve being melodramatic!

Source: extremetech.com, blogs.discovermagazine.com

The Future of Physics: Entanglements and Wormholes

worm_holeQuantum entanglements are one of the most bizarre aspects of quantum physics, so much so that Albert Einstein himself referred to it as “spooky action at a distance.” Basically, the concept involves two particles with each occupying multiple states at once. Until such time as one is measured, neither has a definite state, causing the other particle to instantly assume a corresponding state, even if they reside on opposite ends of the universe.

But what enables particles to communicate instantaneously – and seemingly faster than the speed of light – over such vast distances? Earlier this year, physicists proposed an answer in the form of “wormholes,” or gravitational tunnels. The group showed that by creating two entangled black holes, then pulling them apart, they formed a wormhole connecting the distant black holes.

quantum-entanglement1Now an MIT physicist has found that, looked at through the lens of string theory, the creation of two entangled quarks — the very building blocks of matter — simultaneously gives rise to a wormhole connecting the pair. The theoretical results bolster the relatively new and exciting idea that the laws of gravity that hold the universe together may not be fundamental, but may arise from quantum entanglement themselves.

Julian Sonner, a senior postdoc at MIT’s Laboratory for Nuclear Science and Center for Theoretical Physics, published the results of his study in the journal Physical Review Letters, where it appears together with a related paper by Kristan Jensen of the University of Victoria and Andreas Karch of the University of Washington. Already, the theory is causing quite the buzz for scientists and fans of sci-fi who would like to believe FTL is still possible.

quantum_field_theoryThis is certainly good news for scientists looking to resolve the fundamental nature of the universe by seeing how its discernible laws fit together. Ever since quantum mechanics was first proposed more than a century ago, the main challenge for physicists has been to explain how it correlates to gravity. While quantum mechanics works extremely well at describing how things work on the microscopic level, it remains incompatible with general relativity.

For years, physicists have tried to come up with a theory that can marry the two fields. This has ranged from proposing the existence of a subatomic particle known as the “graviton” or “dilaton”, to various Grand Unifying Theories – aka. Theory of Everything (TOE) – such as Superstring Theory, Loop Quantum Gravity, and other theoretical models to explain the interaction. But so far, none have proven successful.

gravity_well_cartography_2_by_lordsong-d5lrxwsA theory of quantum gravity would suggest that classical gravity is not a fundamental concept, as Einstein first proposed, but rather emerges from a more basic, quantum-based phenomenon. In a macroscopic context, this would mean that the universe is shaped by something more fundamental than the forces of gravity. This is where quantum entanglement could play a role.

Naturally, there is a problem with this idea. Two entangled particles, “communicating” across vast distances, would have to do so at speeds faster than that of light — a violation of the laws of physics, according to Einstein. In July, physicists Juan Maldacena of the Institute for Advanced Study and Leonard Susskind of Stanford University proposed a theoretical solution in the form of two entangled black holes.

big bang_blackholeWhen the black holes were entangled, then pulled apart, the theorists found that what emerged was a wormhole – a tunnel through space-time that is thought to be held together by gravity. The idea seemed to suggest that, in the case of wormholes, gravity emerges from the more fundamental phenomenon of entangled black holes. Following up on work by Jensen and Karch, Sonner has sought to tackle this idea at the level of quarks.

To see what emerges from two entangled quarks, he first generated entangled quarks using the Schwinger effect — a concept in quantum theory that enables one to create particles out of nothing. Sonner then mapped the entangled quarks onto a four-dimensional space, considered a representation of space-time. In contrast, gravity is thought to exist in the fifth dimension. According to Einstein’s laws, it acts to “bend” and shape space-time.

black_holeTo see what geometry may emerge in the fifth dimension from entangled quarks in the fourth, Sonner employed holographic duality, a concept in string theory. While a hologram is a two-dimensional object, it contains all the information necessary to represent a three-dimensional view. Essentially, holographic duality is a way to derive a more complex dimension from the next lowest dimension.

Using holographic duality, Sonner derived the entangled quarks, and found that what emerged was a wormhole connecting the two, implying that the creation of quarks simultaneously creates a wormhole between them. More fundamentally, the results suggest that gravity itself may emerge from quantum entanglement. On top of all that, the geometry, or bending, of the universe as described by classical gravity, may also be a consequence of entanglement.

quantum-entanglement3As Sonner put it in his report, the results are a theoretical explanation for a problem that has dogged scientists who quite some time:

There are some hard questions of quantum gravity we still don’t understand, and we’ve been banging our heads against these problems for a long time. We need to find the right inroads to understanding these questions… It’s the most basic representation yet that we have where entanglement gives rise to some sort of geometry. What happens if some of this entanglement is lost, and what happens to the geometry? There are many roads that can be pursued, and in that sense, this work can turn out to be very helpful.

Granted, the idea of riding wormholes so that we, as humans, can travel from one location in space to another is still very much science fiction, knowing that there may very well be a sound, scientific basis for their existence is good news for anyone who believes we will be able to “jump” around the universe in the near to distant future. I used to be one of them, now… I think I might just be a believer again!

USS_Enterprise_caught_in_artificial_wormhole-640x272Sources: web.mit.edu, extremetech.com

Higgs Boson Confirmed!

CERN_tunnelIn July of 2012, scientists working for the CERN Laboratory in Geneva, Switzerland announced that they believed they had found the elusive “God Particle” – aka. the Higgs Boson. In addition to ending a decades-long search, the discovery also solved one of the greatest riddles of the universe, confirming the Standard Model of particle physics and shedding light on how the universe itself came to be.

But of course, this discovery needed to be confirmed before the scientific community could accept its existence as fact. The announcement made in July indicated that what the CERN scientists had found appeared to be the Higgs Boson, in that it fit the characteristics of the hypothetical subatomic particle. But as of last Thursday, they claimed that they are now quite certain that this is what they observed.

CERNJoe Incandela, a physicist who heads one of the two main teams at CERN (both made up of over 3000 individuals) claimed that: “To me it is clear that we are dealing with a Higgs boson, though we still have a long way to go to know what kind of Higgs boson it is”. In essence, he and his staff believe that may be several types of Higgs to be found, each of which behaves a little differently.

This was no small challenge, as the Higgs will only make an appearance once in every trillion collisions. Originally theorized in 1964 by British physicist Peter Higgs to explain why matter has mass, it has long been suspected that the Higgs stood alone, explaining how the six “flavors” of quarks, six types of leptons, and twelve gauge bosons, interact. Now, it may be the case that there are several, each of which moves differently and are responsible for different functions.

Higgs-bosonAnd of course, there are several larger mysteries that remain to be solved, which the discovery of the Higgs is expected to shed light on. These include why gravity is so weak, what the dark matter is that is believed to make up a large part of the total mass in the universe, and just how all the major forces of the universe work together to define this thing we know as reality.

These include gravity, weak and strong nuclear forces, and electromagnetism. The Theory of Relativity explains how gravity works, while Quantum Theory explains the other three. What has been missing for some time is a “Grand Unifying Theory”, something which could explain how these two theories could co-exist and account for all the basic forces of the universe.

If we can do that, we will have accomplished what Stephen Hawking has dreamed of for some time, and in effect be one step closer to what he described as: “understanding the mind of God”.

Source: nytimes.com