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Archive for the ‘quantum physics’ category: Page 695

Jul 17, 2017

Quantum back-action-evading measurement of motion in a negative mass reference frame

Posted by 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.

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Jul 15, 2017

A single photon is the first object to be teleported from the ground to an orbiting satellite

Posted by in category: quantum physics

Connectivity

First Object Teleported from Earth to Orbit.

Researchers in China have teleported a photon from the ground to a satellite orbiting more than 500 kilometers above.

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Jul 15, 2017

Scientists ‘Teleport’ a Particle Hundreds of Miles—But What Does That Mean?

Posted by in categories: particle physics, quantum physics

Humanity is advancing rapidly towards a place where the news sounds an awful lot like science fiction. In fact, yesterday, Chinese scientists reported that they “teleported” a photon over hundreds of miles using a “quantum satellite.” But this isn’t Star Trek. It’s the real world.

Which happens to mean it’s a lot less exciting than Star Trek-style teleportation, unfortunately. But it’s still really cool, I promise!

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Jul 14, 2017

Rejuvenation is good for society

Posted by in categories: biotech/medical, life extension, neuroscience, quantum physics

The benefits of rejuvenation biotechnologies would extend to the whole human society. #aging


Rejuvenation isn’t good just for individuals and the people close to them. It is good for society as a whole, for a number of reasons. These reasons—which I will now proceed to discuss—should be enough make rejuvenation research a top priority for humanity in its entirety.

Ever heard anyone lamenting that the great minds of history are no longer with us? That we could certainly do with all the Einsteins, Montalcinis, Fermis, Curies, etc, living longer? And have you ever felt saddened when a great mind of our time died? You probably did, or at the very least know someone who did.

Just imagine how much faster would science and progress march if our greatest physicists, doctors, engineers, philantrophists, etc, could live an indefinitely long life. Remember that we’re not talking about a longer life spent in decrepitude and sickness: We’re talking about a 200-year-old Einstein with the experience of two centuries but the physical and mental agility of a 25-year-old. If he was still alive, maybe he could’ve figured out how to unify general relativity with quantum mechanics—something that has been eluding all efforts for decades. Every time a great person (or any person, for that matter) dies, their particular experience is lost forever. Never mind that there are other experts, or that similar knowledge is found in books; it’s not even remotely the same. Rejuvenation would allow us to benefit from the knowledge and wisdom of the best among us for centuries on end.

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Jul 10, 2017

Basic Assumptions of Physics Might Require the Future to Influence the Past

Posted by in category: quantum physics

One of the most well-accepted physical theories makes no logical sense. Quantum mechanics, the theory that governs the smallest possible spaces, forces our human brains to accept some really wacky, uncomfortable realities. Maybe we live in a world where certain observations can force our universe to branch into multiple ones. Or maybe actions in the present influence things earlier in time.

A team of physicists did some thinking, and realized this latter idea, called retrocausality, is a consequence of certain interpretations of quantum mechanics, and therefore, certain interpretations of the nature of reality. Their new paper is more of a “what-if,” an initial look at how to make some of those quantum mechanical interpretations work. Some people I asked thought the work was important, some thought it didn’t matter. Others felt the authors’ interpretation of quantum mechanics avoids the problems posed by the new paper. But no matter what, quantum mechanics will force us to make some uncomfortable conclusions about the world.

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Jul 5, 2017

Reality check: The hidden connections behind quantum weirdness

Posted by in categories: government, quantum physics

Quantum theory says that stuff doesn’t exist when we’re not looking at it. But weirder-than-weird experiments are resurrecting a long-derided alternative.

By Anil Ananthaswamy

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Jun 27, 2017

If EMdrive is real and scales with Q factor then we get almost Star Trek level Technology

Posted by in categories: quantum physics, space travel

Adam Crowl considers spaceships if EM-Drive is verified as a real thing.

If the NASA emdrive performance of 1.2 millinewtons per kilowatt.

8.3 TeraWatts of power would be needed to provide 10 million newtons of thrust to accelerate a 1000 ton space-craft at 1 gee of acceleration. We have no power source that could generate 8.3 TeraWatts for a 1000 ton spacecraft.

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Jun 23, 2017

Atomic imperfections move quantum communication network closer to reality

Posted by in categories: engineering, quantum physics

An international team led by the University of Chicago’s Institute for Molecular Engineering has discovered how to manipulate a weird quantum interface between light and matter in silicon carbide along wavelengths used in telecommunications.

The work advances the possibility of applying quantum mechanical principles to existing optical fiber networks for secure communications and geographically distributed quantum computation. Prof. David Awschalom and his 13 co-authors announced their discovery in the June 23 issue of Physical Review X.

“Silicon carbide is currently used to build a wide variety of classical electronic devices today,” said Awschalom, the Liew Family Professor in Molecular Engineering at UChicago and a senior scientist at Argonne National Laboratory. “All of the processing protocols are in place to fabricate small quantum devices out of this material. These results offer a pathway for bringing quantum physics into the technological world.”

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Jun 22, 2017

Scientists Demonstrate “Liquid Light” at Room Temperature for the First Time

Posted by in categories: nanotechnology, quantum physics

Researchers from Italy and Canada have made liquid light at room temperatures for the first time. The work paves the way for studying quantum hydrodynamics further and for future applications of this new type of matter in electronics devices.

Thanks to technological advances, scientists now have various ways of manipulating matter. Often times, these result in discovering new types of matter that posses unique properties — like the famous metallic hydrogen and the bizarre time crystal. The discovery of such materials leads to a wide range of potential applications in electronics. One of these is the so-called “liquid light,” a strange matter which researchers from the CNR NANOTECH Institute of Nanotechnology in Italy and the Polytechnique Montréal in Canada recently formed at room temperature for the first time.

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Jun 18, 2017

China Shatters “Spooky Action at a Distance” Record, Preps for Quantum Internet

Posted by in categories: cybercrime/malcode, internet, quantum physics, space

Results from the Micius satellite test quantum entanglement, pointing the way toward hack-proof global communications—and a new space race.

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