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Archive for the ‘quantum physics’ category: Page 697

Oct 30, 2015

Physicists mimic quantum entanglement with laser pointer to double data speeds

Posted by in categories: information science, quantum physics

In a classic eureka moment, a team of physicists led by The City College of New York and including Herriot-Watt University and Corning Incorporated is showing how beams from ordinary laser pointers mimic quantum entanglement with the potential of doubling the data speed of laser communication.

Quantum entanglement is a phrase more likely to be heard on popular sci-fi television shows such as “Fringe” and “Doctor Who.” Described by Albert Einstein as “spooky action at a distance,” when two quantum things are entangled, if one is ‘touched’ the other will ‘feel it,’ even if separated by a great distance.

“At the heart of quantum entanglement is ‘nonseparability’ — two entangled things are described by an unfactorizable equation,” said City College PhD student Giovanni Milione. “Interestingly, a conventional (a pointer)’s shape and polarization can also be nonseparable.”

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Oct 30, 2015

Scientists design full-scale architecture for quantum computer in silicon

Posted by in categories: computing, particle physics, quantum physics

Australian scientists have designed a 3D silicon chip architecture based on single atom quantum bits, which is compatible with atomic-scale fabrication techniques — providing a blueprint to build a large-scale quantum computer.

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Oct 29, 2015

Quantum communications go thin and light

Posted by in categories: computing, quantum physics

Trong Toan Tran states: “Ultimately we want to build a ‘plug and play’ device that can generate single photons on demand…” #QuantumComputing.


A team of UTS researchers has made a major breakthrough that could pave the way for the next generation of quantum communications.

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Oct 26, 2015

‘Zeno effect’ verified—atoms won’t move while you watch

Posted by in categories: electronics, materials, particle physics, quantum physics

One of the oddest predictions of quantum theory – that a system can’t change while you’re watching it – has been confirmed in an experiment by Cornell physicists. Their work opens the door to a fundamentally new method to control and manipulate the quantum states of atoms and could lead to new kinds of sensors.

The experiments were performed in the Utracold Lab of Mukund Vengalattore, assistant professor of physics, who has established Cornell’s first program to study the physics of materials cooled to temperatures as low as .000000001 degree above absolute zero. The work is described in the Oct. 2 issue of the journal Physical Review Letters

Graduate students Yogesh Patil and Srivatsan K. Chakram created and cooled a gas of about a billion Rubidium atoms inside a vacuum chamber and suspended the mass between laser beams. In that state the atoms arrange in an orderly lattice just as they would in a crystalline solid.,But at such low temperatures, the atoms can “tunnel” from place to place in the lattice. The famous Heisenberg uncertainty principle says that the position and velocity of a particle interact. Temperature is a measure of a particle’s motion. Under extreme cold velocity is almost zero, so there is a lot of flexibility in position; when you observe them, atoms are as likely to be in one place in the lattice as another.

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Oct 25, 2015

Quantum skeptics now predict a working computer in 10 years

Posted by in categories: computing, quantum physics

Even D-Wave’s detractors are starting to feel like quantum computers are getting close, though only for some applications.

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Oct 25, 2015

Are the Laws of Physics Really Universal?

Posted by in categories: information science, quantum physics

Can the laws of physics change over time and space?

As far as physicists can tell, the cosmos has been playing by the same rulebook since the time of the Big Bang. But could the laws have been different in the past, and could they change in the future? Might different laws prevail in some distant corner of the cosmos?

“It’s not a completely crazy possibility,” says Sean Carroll, a theoretical physicist at Caltech, who points out that, when we ask if the laws of physics are mutable, we’re actually asking two separate questions: First, do the equations of quantum mechanics and gravity change over time and space? And second, do the numerical constants that populate those equations vary?

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Oct 24, 2015

Upgrading the quantum computer

Posted by in categories: computing, quantum physics

Theoretical physicists have proposed a scalable quantum computer architecture. The new model, developed by Wolfgang Lechner, Philipp Hauke and Peter Zoller, overcomes fundamental limitations of programmability in current approaches that aim at solving real-world general optimization problems by exploiting quantum mechanics.

Within the last several years, considerable progress has been made in developing a quantum computer, which holds the promise of solving problems a lot more efficiently than a classical computer. Physicists are now able to realize the basic building blocks, the quantum bits (qubits) in a laboratory, control them and use them for simple computations. For practical application, a particular class of quantum computers, the so-called adiabatic quantum computer, has recently generated a lot of interest among researchers and industry. It is designed to solve real-world optimization problems conventional computers are not able to tackle. All current approaches for adiabatic quantum computation face the same challenge: The problem is encoded in the interaction between qubits; to encode a generic problem, an all-to-all connectivity is necessary, but the locality of the physical quantum bits limits the available interactions.

“The programming language of these systems is the individual interaction between each physical qubit. The possible input is determined by the hardware. This means that all these approaches face a fundamental challenge when trying to build a fully programmable quantum computer,” explains Wolfgang Lechner from the Institute for Quantum Optics and Quantum Information (IQOQI) at the Austrian Academy of Sciences in Innsbruck.

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Oct 23, 2015

‘Zeno effect’ verified: Atoms won’t move while you watch

Posted by in categories: particle physics, quantum physics

One of the oddest predictions of quantum theory — that a system can’t change while you’re watching it — has been confirmed in an experiment by physicists.

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Oct 22, 2015

Simulation Shows Time Travel Is Possible

Posted by in categories: computing, particle physics, quantum physics, time travel

Australian scientists created a computer simulation in which quantum particles can move back in time. This might confirm the possibility of time travel on a quantum level, suggested in 1991. At the same time, the study revealed a number of effects which are considered impossible according to the standard quantum mechanics.

Using photons, physicists from the University of Queensland in Australia simulated time-traveling quantum particles. In particular, they studied the behavior of a single photon traveling back in time through a wormhole in space-time and interacting with itself. This time-traveling loop is called a closed timelike curve, i.e. a path followed by a particle which returns to its initial space-time point.

The physicists studied two possible scenarios for a time-traveling photon. In the first, the particle passes through a wormhole, moving back in time, and interacts with its older self. In the second scenario, the photon passes through normal space-time and interacts with another photon which is stuck in a closed timelike curve.

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Oct 22, 2015

Quantum Theory: ‘Spooky Action at a Distance’ confirmed

Posted by in categories: encryption, general relativity, physics, quantum physics, science

In one of my first articles for Lifeboat,* I provided an experimental methodology for demonstrating (or proving) the instantaneous ‘communication’ between quantum entangled particles. Even though changes to one particle can be provably demonstrated at its far away twin, the very strange experimental results suggested by quantum theory also demonstrate that you cannot use the simultaneity for any purpose. That is, you can provably pass information instantly, but you cannot study the ‘message’ (a change in state at the recipient), until such time as it could have been transmit by a classical radio wave.

Now, scientists have conducted an experiment proving that objects can instantaneously affect each other, regardless o the distance between them. [continue below]

delft quantum entanglement apparatus

[From The New York Times—Oct 21, 2015]:

Sorry Einstein.
Quantum Study Suggests ‘Spooky Action’ is Real

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