New experiments using Heisenberg’s uncertainty principle extend the range of quantum cryptography, an advanced method of communicating in unbreakable code.

QC systems send information in the form of a specially prepared stream of photons representing 0s and 1s. If anyone tries to eavesdrop, he unintentionallly alters the photons being transmitted, and the rightful recipient is able to detect the tampering. As a final layer of security, the beam of photons doesn’t encode the actual secret message, it just contains an encryption key. So if part of the key is intercepted, the sender and recipient detect the altered photons and discard that part of the key. Once they’ve transmitted enough photons, the shared key is used to encrypt the message, which can be sent over public communication lines. But the photon key has to arrive reliably at its destination.

Quantum key encryption is one promising method of securing communication, especially if it can be transmitted by satellites. Scientists at an Italian observatory this year succeeded in firing lasers at the mirror-covered Ajisai Japanese satellite, proving that a sequence of photons can travel great distances through space. The laser pulsed photons at the satellite at 17,000 times per second; a fraction bounced back to a telescope at the observatory. On Earth, the longest successful quantum encryption link has been just under 100 miles because the photons scatter as they travel through the air. To reach the satellite, the photons only had to travel through 5 miles of atmosphere during their 1000-mile journey, allowing the sequence to arrive in order.

There have been several recent breakthroughs in quantum cryptography. In August, a team of researchers from the National Institute of Standards and Technology (NIST) took the stage at Caesar’s Palace in Las Vegas for a demonstration of its quantum cryptography system at the notorious Black Hat information security conference. Using a laser to send the encryption key across the room, they streamed perfectly secure live video at 300,000 bits per second—as good as YouTube. “That’s about two orders of magnitude faster than any other system for quantum key distribution,” says NIST engineer Alan Mink. At the same conference, researchers from the University of Singapore demonstrated a system using pairs of “entangled” photons. Entanglement is a mind-bending feature of quantum mechanics that can allow the physical properties of two particles to be intimately linked even if they’re separated by a great distance. This provides an ideal way for a third party—a satellite, for instance—to distribute a perfectly secure key to two parties who wish to exchange a message, no matter where they’re located. [PopularMechanics]

Using the strongest materials known to man, scientists are building the most powerful electromagnet in the world — one that won’t blow up a split second after it’s turned on.

The entire magnet will be a combination of coil sets weighing nearly 18,000 pounds and powered by jolts from a massive 1,200-megajoules motor generator. Once activated, the new magnet should be about two million times more powerful than the average refrigerator magnet.

“The new magnet at the High Field Lab is a fantastic leap forwards in terms of our capability as a scientific community to explore materials under extreme conditions,” said Ian Fisher, a scientist at Stanford University. “In several cases one needs to go to these sorts of extremes to fundamentally understand materials” used in high-temperature superconductors and other applications, said Fisher.

The electromagnet consists of two parts. The outer section, or outsert, will be a cylinder, 1.5 meters (4.9 feet) in diameter and 1.5 meters tall, and solid except for a small hole, less than 8 inches wide, bored through the middle.

Inside that hole rests the insert, nine coils made of copper and strengthened with silver wire as thin as 100 atoms across. Together, the copper and silver create the strongest material known to man, according to Greg Boebinger, Director of the National High Magnetic Field Laboratory in Florida, where the magnet is being built. Eventually the magnet will be placed at the Los Alamos National Laboratory.

The pressures generated inside the insert will be equivalent to 200 sticks of dynamite going off together, or about 30 times the pressure at the bottom of the ocean. Very few things can survive those kinds of forces for long — including the new magnet. The scientists expect each $20,000 insert to survive about 100 pulses. The $8 million outsert should last about 10,000 pulses. Each time the magnet pulses it bends the copper and silver wires, creating tiny cracks in the metal. The cracks in the copper run into the silver wires, which stops the cracks from spreading. [Discovery]

The LHC Scientists look at a computer screen at the control centre of the CERN in Geneva September 10, 2008. Scientists at the European Organisation for Nuclear Research (CERN) started up a huge particle-smashing machine on Wednesday, aiming to re-enact the conditions of the “Big Bang” that created the universe.

Experiments using the Large Hadron Collider (LHC), the biggest and most complex machine ever made, could revamp modern physics and unlock secrets about the universe and its origins.

On Wednesday, Evans will fire up the Large Hadron Collider, a 17-mile-long doughnut-shaped tunnel that will smash sub-atomic particles together at nearly the speed of light. Built by the European Organisation for Nuclear Research (CERN), the collider lies beneath the French-Swiss border, near the institution’s headquarters in Geneva, at depths ranging from 170 feet to 600 feet.  The project has had to work hard to deny suggestions by some critics that the experiment could create tiny black holes of intense gravity that could suck in the whole planet. Such fears, fanned by doomsday writers, have spurred huge interest in particle physics before the machine’s start-up. Leading scientists have dismissed such concerns as “nonsense.”

The debut of the machine that cost 10 billion Swiss francs ($9 billion) registered as a blip on a control room screen at CERN, the European Organization for Nuclear Research, at about 9:30 a.m. (3:30 a.m. EDT). “We’ve got a beam on the LHC,” project leader Lyn Evans told his colleagues, who burst into applause at the news. The physicists and technicians huddled in the control room cheered loudly again an hour later when the particle beam completed a clockwise trajectory of the accelerator, successfully completing the machine’s first major task. Eventually, the scientists want to send beams in both directions to create tiny collisions at nearly the speed of light, an attempt to recreate on a miniature scale the heat and energy of the Big Bang, a concept of the origin of the universe that dominates scientific thinking. The Big Bang is thought to have occurred 15 billion years ago when an unimaginably dense and hot object the size of a small coin exploded in a void, spewing out matter that expanded rapidly to create stars, planets and eventually life on Earth.

Problems with the LHC’s magnets caused its temperature — which is kept at minus 271.3 degrees Celsius (minus 456.3 degrees Fahrenheit) — to fluctuate slightly, delaying efforts to send a particle beam in the counter-clockwise direction. The beam started its progression and then was halted. “This is a hiccup, not a major thing,” Rudiger Schmidt, CERN’s head of hardware commissioning, told reporters, adding the second rotation should be completed on Wednesday afternoon. Evans, who wore jeans and running shoes to the start-up, declined to say when those high-energy clashes would begin.

“I don’t know how long it will take,” he said. “I think what has happened this morning bodes very well that it will go quickly … This is a machine of enormous complexity. Things can go wrong at any time. But this morning we had a great start.” Once the particle-smashing experiment gets to full speed, data measuring the location of particles to a few millionths of a meter, and the passage of time to billionths of a second, will show how the particles come together, fly apart, or dissolve. [Sciam.com]