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The Large Hadron Collider – Quantum Tunnel Podcast

Large Hadron Collider tunnel and dipole magnets.
Image via Wikipedia

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The Large Hadron Collider is located 300 feet underneath the French-Swiss border outside Geneva and is the world’s biggest and most expensive particle accelerator. It is designed to accelerate  protons to energies of 7 trillion electron volts and then smash them together to recreate the conditions that last prevailed when the universe was less than a trillionth of a second old.

The collider started smashing particles on March 30th, 2010, after 16 years and $10 billion. The new hadron collider will take physics into a realm of energy and time where the current reigning theories simply do not apply, corresponding to an era when cosmologists think that the universe was still differentiating itself, evolving from a primordial blandness and endless potential into the forces and particles that constitute modern reality.

One prime target is a particle called the Higgs boson that is thought to endow other particles with mass, according to the reigning theory of particle physics, known as the Standard Model.

The LHC is part of CERN, which born amid vineyards and farmland in the countryside outside Geneva in 1954 out of the rubble of postwar Europe. It had a twofold mission of rebuilding European science and of having European countries work together. Today, it has 20 countries as members. It was here that the World Wide Web was born in the early 1990s. The lab came into its own scientifically in the early 80s, when Carlo Rubbia and Simon van der Meer won the Nobel Prize by colliding protons and antiprotons there to produce the particles known as the W and Z bosons, which are responsible for the so-called weak nuclear force that causes some radioactive decays.

Bosons are quanta that, according to the rules of quantum mechanics transmit forces as they are tossed back and forth in a sort of game of catch between matter particles. The W’s and Z’s are closely related to photons, which transmit electromagnetic forces, or light.

The innings of the collider are some 1,232 electromagnets, weighing in at 35 tons apiece, strung together like an endless train stretching around the gentle curve of the CERN tunnel. In order to bend 7-trillion-electron-volt protons around in such a tight circle these magnets have to produce magnetic fields of 8.36 Tesla, more than 100,000 times the Earth’s field, requiring in turn a current of 13,000 amperes through the magnet’s coils. To make this possible the entire ring is bathed in 128 tons of liquid helium to keep it cooled to 1.9 degrees Kelvin, at which temperature the niobium-titanium cables are superconducting and pass the current without resistance.

Running through the core of this train, surrounded by magnets and cold, are two vacuum pipes, one for protons going clockwise, the other counterclockwise. Traveling in tight bunches along the twin beams, the protons will cross each other at four points around the ring, 30 million times a second. During each of these violent crossings, physicists expect that about 20 protons, or the parts thereof – quarks or gluons – will actually collide and spit fire.

Two of the detectors are specialized. One, called Alice, is designed to study a sort of primordial fluid, called a quark-gluon plasma, that is created when the collider smashes together lead nuclei. The other, LHCb, will hunt for subtle differences in matter and antimatter that could help explain how the universe, which was presumably born with equal amounts of both, came to be dominated by matter.

The other two, known as Atlas and the Compact Muon Solenoid, or C.M.S. for short, are the designated rival workhorses of the collider, designed expressly to capture and measure every last spray of particle and spark of energy from the proton collisions.


Key breast cancer driver found

Cancer experts have identified a gene which can cause a particularly aggressive form of breast cancer to develop. The name given to this new oncogene is ZNF703 and it is overactive in one of 12 breast cancers. Scientists working for Cancer Research UK carried out the research and they mention that the gene was “prime candidate” for the development of new breast cancer drugs. The study was published in the EMBO Molecular Medicine Journal.

Physicists reverse the laser

We are very familiar with laser light, and as such it would seem very odd to thing about a laser that sucks in a bright beam rather than emitting it. However, scientists from Yale have recently reported in Science the development of a device that converts laser beams into heat.

Cao and co-workers uses a 110-micrometre silicon wafer and a tunable infraread laser in their experiments. They split the laser beam into two and shine it into both sides of the silicon wafer. The front and back of the silicon slice act as mirrors and the silicon in between would be similar to the medium inside a laser cavity. By tuning the frequency of the incoming laser beam as well as other properties, the photons are trapped between the surfaces of the silicon. As the photons bounce back and forth, the silicon absorbs them until all photons are sucked up by the device and converted into heat.

Smelling quantum vibrations

It has been widely believed that the different shapes of molecules provide the clues that our brain registers as smells. However, it has recently been reported that some fruit flies can distinguish between two molecules with identical shapes, providing the first experimental evidence to support a controversial theory that the sense of smell can operate by detecting molecular vibrations.

Efthimios Skoulakis of the Alexander Fleming Biomedical Sciences Research Center in Vari, Greece, carried out the experiments on fruit flies. The team initially placed fruit flies in a simple maze that let them choose between two arms, one containing a fragrant chemical such as acetophenone, a common perfume ingredient, the other containing a deuterated version. If the flies were sensing odours using shape alone, they should not be able to tell the difference between the two. In fact, the researchers found that flies preferred ordinary acetophenone.

Brazilian dam project blocked

In the previous episode we reported on the approval of the construction of a controversial dam in the Amazon, the Belo Horizonte hydroelectric plant, the third largest plant of it’s kind in the world. The plans have now been suspended by a Brazilian judge over environmental concerns.

Judge Ronaldo Desterro halted the plans for the construction because environmental requirements have not been met, also, the national development bank has been prohibited from financing the project.

Science Communication Conference in London

The British Science Association has recently announced its annual two-day Science Communication Conference. The event aims to address some of the key issues facing science communicators in the UK. In order to do that, the conference brings together people involved in public engagement with a range of backgrounds including scientists, charities, universities, press offices and policymakers.
The event will take place on the 25th and 26th of May at King’s Place in King’s Cross in London.  Registration opened on February 14 and will close on May 13th. For more information please visit their website.