Europe against GMO crops! Please, sign the Avaaz petition! I already did.
It's us who decide, not Monsanto!!!

Sunday, 21 September 2008

CERN and the light

Yep, no matter do you like it or not, LHC is coming. Now, don't feel doomed. Everything is going to be all right.

Date Set for Operation of Large Hadron Collider

Published: August 7, 2008

Officials at CERN, the European Center for Nuclear Research, outside Geneva, announced Thursday that their new particle accelerator, the world’s largest, would begin operation on Sept. 10. On that date, the physicists and engineers will make the first attempt to circulate a beam of protons around a 17-mile-long super-cooled underground racetrack known as the Large Hadron Collider.

The collider, 14 years and $8 billion in the making, has been built to smash together protons that have been accelerated to energies of 7 trillion electron volts, and examine the remains for clues to the origin of mass and new forces and particles in the universe.

But the collisions will not happen immediately. The first step on the journey to new physics will happen this weekend, when engineers test their method of injecting high-energy protons, which are produced in a separate accelerator, the Super Proton Synchrotron, into the collider by sending a batch through one part of the racetrack.

In September, the first protons to circle the entire ring will have a relatively modest energy of 450 billion electron volts. Once the physicists and engineers have learned to drive their new machine and had a few collisions at that energy, they will ramp up the energy as fast as they can to 5 trillion electron volts — unexplored territory.

“Our main objective is to get to 5 TeV,” Lyn Evans, project director at CERN, said in an e-mail message. “How long it will take, I don’t know, but with the quality of the instrumentation, software, and above all the people we have, I am optimistic.”

Once they get up to speed later this fall, the collider will run for a month or two of “pilot physics.”

CERN shuts down for the winter to save money on its electric bill. While it sleeps, engineers will “train” the superconducting magnets that steer the energetic particles around their track to handle the high currents needed to produce fields strong enough to bend the paths of 7-trillion-electron-volt protons. When the collider awakens again in the spring it will be at full strength, and physicists will be face to face with their dreams. source

My comment: Lol, nice! And don't even get me started! We're waiting this for sooooo long. I can't wait to see what will happen and when. It's so exiting.

Surpassing Nature, Scientists Bend Light Backward

Published: August 11, 2008

Using tiny wires and fishnet structures, researchers at the University of California, Berkeley, have found new ways to bend light backward, something that never occurs in nature.

This technology could lead to microscopes able to peer more deeply and clearly into living cells. And the same kind of structures might one day be adapted to bend light in other unnatural ways, creating a Harry Potter-like invisibility cloak. But scientists are still far from designing and manufacturing such a cloak.

The work involves materials that have a property known as negative refraction, which means that they essentially bend light backward. Once thought to be pure fantasies, these substances, called metamaterials, have been constructed in recent years, and scientists have shown they can bend long-wavelength microwaves.

Negative refractive materials can in principle lead to fantastical illusions; someone looking down at a fish in a pool of negative refractive liquid would see the fish swimming in the air above.

Two separate advances are described in two scientific papers being published this week, one demonstrating negative refraction at infrared and visible wavelengths. The second article will be published in Friday’s issue of the journal Science. Both papers come out of the research laboratory of Xiang Zhang, a professor at the Nanoscale Science and Engineering Center in Berkeley.

When a ray of light crosses the boundary from air to water, glass or other transparent material, it bends, and the degree of bending is determined by a property known as the index of refraction. Transparent materials like glass, water and diamonds all have an index of 1 or higher for visible light, meaning that when the light enters, its path bends toward an imaginary line perpendicular to the surface.

With the engineered metamaterials, scientists can create refractive indices less than 1 or even negative. Light entering a material with a negative index of refraction would take a sharp turn, almost as if it had bounced off the imaginary perpendicular line.

In the Nature paper, the Berkeley researchers created a fishnet structure with 21 layers, alternating between a metal and magnesium fluoride, resulting in a metamaterial with a negative index of refraction for infrared light. The researchers said by making the fishnet structure even smaller, they should be able to do the same with visible light.

In the Science paper, a different group of scientists in Dr. Zhang’s laboratory used a different approach, building an array of minuscule upright wires, which changed the electric fields of passing light waves. That structure was able to bend visible red light.

Dr. Zhang said both approaches had advantages and disadvantages. “There are many roads to Rome,” he said. “At this point, honestly speaking, we don’t know which road will be the best.”

One application of negative index materials could be a “superlens.” Light is usually thought of as having undulating waves. But much closer up, light is a much more jumbled mess, with the waves mixed in with more complicated “evanescent waves.”

The evanescent waves quickly dissipate as they travel, and thus are usually not seen. A negative refraction lens actually amplifies the evanescent waves, preserving detail lost in conventional optics, and the hope is to eventually build an optical microscope that could make out tiny biological structures like individual viruses. source

My comment: And that is stuningly cool. Just imagine what could be done with those materials. I won't go into usual emotional statements, since it's far from being done, but can't help but notice how the word cloak keep on appearing. Seriously, why having a cloak is so important? Yeah, yeah, military, but still, for me, it's more or less useless, since at the moment they do it, there will be a way to detect it. Nothing to win here. But there are so many other opportunities with those material... Just think what you could do that as an entertainment.

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