In what appears to be the latest breakthrough in space travel technology, China claims it has made a great leap forward with its ‘reactionless’ Electromagnetic Drive, or simply, EmDrive – an engine that uses only the power of electromagnetic radiation contained within a microwave cavity.
The EmDrive flies in the face of physics – going against the law of conservation of movement; producing mechanical movement but without an exchange of matter.
Your daily round-up of some of the other security stories in the news
Groupon grief – was it password reuse?
The Telegraph reports that crooks have hijacked a number of Groupon accounts and used them to purchase expensive items like games consoles, iPhones and holidays. Some victims have suffered thousands of pounds of losses.
Quantum mechanics dictates sensitivity limits in the measurements of displacement, velocity and acceleration. A recent experiment at the Niels Bohr Institute probes these limits, analyzing how quantum fluctuations set a sensor membrane into motion in the process of a measurement. The membrane is an accurate model for future ultraprecise quantum sensors, whose complex nature may even hold the key to overcome fundamental quantum limits. The results are published in the scientific journal, Proceedings of the National Academy of Sciences.
Vibrating strings and membranes are at the heart of many musical instruments. Plucking a string excites it to vibrations, at a frequency determined by its length and tension. Apart from the fundamental frequency — corresponding to the musical note — the string also vibrates at higher frequencies. These overtones influence how we perceive the ‘sound’ of the instrument, and allow us to tell a guitar from a violin. Similarly, beating a drumhead excites vibrations at a number of frequencies simultaneously.
These matters are not different when scaling down, from the half-meter bass drum in a classic orchestra to the half-millimeter-sized membrane studied recently at the Niels Bohr Institute. And yet, some things are not the same at all: using sophisticated optical measurement techniques, a team lead by Professor Albert Schliesser could show that the membrane’s vibrations, including all its overtones, follow the strange laws of quantum mechanics. In their experiment, these quantum laws implied that the mere attempt to precisely measure the membrane vibrations sets it into motion. As if looking at a drum already made it hum!
If you thought that a kid’s room, a Norwegian Nobel Laureate and a laser pointer had nothing in common, two UA physicists are about to enlighten you.
It’s hard to believe, but after having unraveled many of the laws that make the universe tick, physicists still haven’t reached an agreement on whether something as seemingly simple as “hot” or “cold” can be measured in a system under certain circumstances.
“Imagine you threw an iceberg into the sun and right before it’s melted and gone, you wanted to know, ‘How hot is that iceberg at that moment?’ Would that be a meaningful question to ask?” says Charles Stafford, a professor in the Department of Physics in the UA’s College of Science. “According to traditional physics, it wouldn’t be.”
RIP dear friend.
A giant in the worlds of both academia and policy, Drell died Wednesday, Dec. 21, at his home in Palo Alto. He was 90 years old.
“An accomplished physicist, his contributions to improve national and international security made our world a better place,” said Tom Gilligan, director of the Hoover Institution at Stanford in a statement. “We are especially grateful for Sid’s relentless dedication to eliminating the threat posed by nuclear weapons and know that his important work will continue to frame the issue.”
Dedicated to arms control.
Let’s say closer to 7yrs or less.
Whether quantum computing is 10 years away — or is already here — it promises to make current encryption methods obsolete, so enterprises need to start laying the groundwork for new encryption methods.
A quantum computer uses qubits instead of bits. A bit can be a zero or a one, but a qubit can be both simultaneously, which is weird and hard to program but once folks get it working, it has the potential to be significantly more powerful than any of today’s computers.
And it will make many of today’s public key algorithms obsolete, said Kevin Curran, IEEE senior member and a professor at the University of Ulster, where he heads up the Ambient Intelligence Research Group.
