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Jul 17, 2017
These new white roads can cool down entire cities
Posted by Shailesh Prasad in category: futurism
Jul 17, 2017
These researchers used an Xbox Kinect to 3D scan a T-Rex skull
Posted by Shailesh Prasad in category: futurism
Jul 17, 2017
This concept will allow you to quickly deliver anything within a city!
Posted by Shailesh Prasad in category: futurism
Jul 17, 2017
The Former Secretary of Defense Outlines the Future of Warfare
Posted by Derick Lee in categories: futurism, military
Two years ago, Barack Obama appointed a new Secretary of Defense, Ashton Carter—a technocrat physicist, an arms control veteran, and a professor at Stanford—to help close this divide. During his tenure, Carter set up a virtual outpost in Silicon Valley. He worked to make it easier for tech companies to sell things to the Pentagon, for their engineers to work there, and for their bosses to offer up advice. He even let WIRED tag along and write a profile of him. He also impressed the local royalty. “He’s been amazing,” Ben Horowitz, the co-founder of Andreessen Horowitz, told me in an interview.
The former Secretary of Defense built a bridge between tech and the Pentagon. Here, he talks about its importance in an uncertain time.
Jul 17, 2017
This eco-friendly apartment building is designed to absorb carbon
Posted by Shailesh Prasad in category: habitats
Jul 17, 2017
Quantum back-action-evading measurement of motion in a negative mass reference frame
Posted by Andreas Matt in category: quantum physics
Interesting…
Quantum mechanics dictates that a continuous measurement of the position of an object imposes a random quantum back-action (QBA) perturbation on its momentum. This randomness translates with time into position uncertainty, thus leading to the well known uncertainty on the measurement of motion1, 2. As a consequence of this randomness, and in accordance with the Heisenberg uncertainty principle, the QBA3, 4 puts a limitation—the so-called standard quantum limit—on the precision of sensing of position, velocity and acceleration. Here we show that QBA on a macroscopic mechanical oscillator can be evaded if the measurement of motion is conducted in the reference frame of an atomic spin oscillator6, 7. The collective quantum measurement on this hybrid system of two distant and disparate oscillators is performed with light. The mechanical oscillator is a vibrational ‘drum’ mode of a millimetre-sized dielectric membrane, and the spin oscillator is an atomic ensemble in a magnetic field9, 10. The spin oriented along the field corresponds to an energetically inverted spin population and realizes a negative-effective-mass oscillator, while the opposite orientation corresponds to an oscillator with positive effective mass. The QBA is suppressed by −1.8 decibels in the negative-mass setting and enhanced by 2.4 decibels in the positive-mass case. This hybrid quantum system paves the way to entanglement generation and distant quantum communication between mechanical and spin systems and to sensing of force, motion and gravity beyond the standard quantum limit.
Benjamin Vidmar is the founder of Polar Permaculture and he’s trying to do the impossible: grow vegetables in the harsh landscape of Svalbard, a group of Norwegian islands in the Arctic Ocean.