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Archive for the ‘quantum physics’ category: Page 447

May 16, 2020

Army Researchers Advance Toward Quantum Computing at Room Temperature

Posted by in categories: computing, military, quantum physics

Army researchers predict quantum computer circuits that will no longer need extremely cold temperatures to function could become a reality after about a decade.

For years, solid-state quantum technology that operates at room temperature seemed remote. While the application of transparent crystals with optical nonlinearities had emerged as the most likely route to this milestone, the plausibility of such a system always remained in question.

Now, Army scientists have officially confirmed the validity of this approach. Dr. Kurt Jacobs, of the U.S. Army Combat Capabilities Development Command’s Army Research Laboratory, working alongside Dr. Mikkel Heuck and Prof. Dirk Englund, of the Massachusetts Institute of Technology, became the first to demonstrate the feasibility of a quantum logic gate comprised of photonic circuits and optical crystals.

May 16, 2020

Does Quantum Immortality Save Schrödinger’s Cat?

Posted by in categories: cosmology, education, quantum physics

Education Saturday with Space Time.


To quote eminent scientist Tyler Durden: “On a long enough timeline, the survival rate for everyone drops to zero.” Actually… not necessarily true. If the quantum multiverse is real there may be a version of you that lives forever.

Continue reading “Does Quantum Immortality Save Schrödinger’s Cat?” »

May 16, 2020

Physicists Just Built The First Working Prototype Of A ‘Quantum Radar’

Posted by in categories: particle physics, quantum physics

Quantum entanglement – that strange but potentially hugely useful quantum phenomenon where two particles are inextricably linked across space and time – could play a major role in future radar technology.

In 2008, an engineer from MIT devised a way to use the features of entanglement to illuminate objects while using barely any photons. In certain scenarios, such technology promises to outperform conventional radar, according to its makers, particularly in noisy thermal environments.

Now, researchers have taken the idea much further, demonstrating its potential with a working prototype.

May 15, 2020

Meet the Intern Using Quantum Computing to Study the Early Universe

Posted by in categories: cosmology, education, nanotechnology, quantum physics, supercomputing

With the help of the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, Juliette Stecenko is exploring cosmology—a branch of astronomy that investigates the origin and evolution of the universe, from the Big Bang to today and into the future. As an intern through DOE’s Science Undergraduate Laboratory Internships (SULI) program, administered at Brookhaven by the Office of Educational Programs (OEP), Stecenko is using modern supercomputers and quantum computing platforms to perform astronomy simulations that may help us better understand where we came from.

Stecenko works under the guidance of Michael McGuigan, a computational scientist in the quantum computing group at Brookhaven’s Computational Science Initiative. The two have been collaborating on simulating Casimir energy—a small force that two electrically neutral surfaces held a tiny distance apart will experience from quantum, atomic, or subatomic fluctuations in the vacuum of space. The vacuum energy of the universe and the Casimir pressure of this energy could be a possible explanation of the origin and evolution of the universe, as well a possible cause of its accelerated expansion.

“Casimir energy is something scientists can measure in the laboratory and is especially important for nanoscience, or in cosmology, in the very early universe when the universe was very small,” McGuigan said.

May 15, 2020

‘Hot and messy’ entanglement of 15 trillion atoms

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

Quantum entanglement is a process by which microscopic objects like electrons or atoms lose their individuality to become better coordinated with each other. Entanglement is at the heart of quantum technologies that promise large advances in computing, communications and sensing, for example, detecting gravitational waves.

Entangled states are famously fragile: In most cases, even a tiny disturbance will undo the entanglement. For this reason, current quantum technologies take great pains to isolate the microscopic systems they work with, and typically operate at temperatures close to absolute zero. The ICFO team, in contrast, heated a collection of atoms to 450 Kelvin in a recent experiment, millions of times hotter than most atoms used for quantum technology. Moreover, the were anything but isolated; they collided with each other every few microseconds, and each collision set their electrons spinning in random directions.

The researchers used a laser to monitor the magnetization of this hot, chaotic gas. The magnetization is caused by the spinning electrons in the atoms, and provides a way to study the effect of the collisions and to detect entanglement. What the researchers observed was an enormous number of entangled atoms—about 100 times more than ever before observed. They also saw that the entanglement is non-local—it involves atoms that are not close to each other. Between any two entangled atoms there are thousands of other atoms, many of which are entangled with still other atoms, in a giant, hot and messy entangled state.

May 15, 2020

Quantum Entanglement of 15 Trillion Atoms at 450 Kelvin With “Surprising Results”

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

Quantum entanglement is a process by which microscopic objects like electrons or atoms lose their individuality to become better coordinated with each other. Entanglement is at the heart of quantum technologies that promise large advances in computing, communications and sensing, for example detecting gravitational waves.

Entangled states are famously fragile: in most cases even a tiny disturbance will undo the entanglement. For this reason, current quantum technologies take great pains to isolate the microscopic systems they work with, and typically operate at temperatures close to absolute zero. The ICFO team, in contrast, heated a collection of atoms to 450 Kelvin, millions of times hotter than most atoms used for quantum technology. Moreover, the individual atoms were anything but isolated; they collided with each other every few microseconds, and each collision set their electrons spinning in random directions.

The researchers used a laser to monitor the magnetization of this hot, chaotic gas. The magnetization is caused by the spinning electrons in the atoms, and provides a way to study the effect of the collisions and to detect entanglement. What the researchers observed was an enormous number of entangled atoms — about 100 times more than ever before observed. They also saw that the entanglement is non-local — it involves atoms that are not close to each other. Between any two entangled atoms there are thousands of other atoms, many of which are entangled with still other atoms, in a giant, hot and messy entangled state.

May 13, 2020

Experimental realization of Shor’s quantum factoring algorithm using qubit recycling

Posted by in categories: information science, quantum physics, sustainability

Circa 2012


Quantum computational algorithms exploit quantum mechanics to solve problems exponentially faster than the best classical algorithms1,2,3. Shor’s quantum algorithm4 for fast number factoring is a key example and the prime motivator in the international effort to realize a quantum computer5. However, due to the substantial resource requirement, to date there have been only four small-scale demonstrations6,7,8,9. Here, we address this resource demand and demonstrate a scalable version of Shor’s algorithm in which the n-qubit control register is replaced by a single qubit that is recycled n times: the total number of qubits is one-third of that required in the standard protocol10,11. Encoding the work register in higher-dimensional states, we implement a two-photon compiled algorithm to factor N = 21. The algorithmic output is distinguishable from noise, in contrast to previous demonstrations. These results point to larger-scale implementations of Shor’s algorithm by harnessing scalable resource reductions applicable to all physical architectures.

May 13, 2020

Teleportation and traversible wormholes are all real

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

Circa 2017


Einstein-Rosen or “ER” bridges, are equivalent to entangled quantum particles, also known as Einstein-Podolsky-Rosen or “EPR” pairs. The quantum connection between wormholes prevents their collapse without involving exotic matter.

The quantum-teleportation format precludes using these traversable wormholes as time machines. Anything that goes through the wormhole has to wait for Alice’s message to travel to Bob in the outside universe before it can exit Bob’s black hole, so the wormhole doesn’t offer any superluminal boost that could be exploited for time travel.

Continue reading “Teleportation and traversible wormholes are all real” »

May 13, 2020

Mechanical oscillations cause iron to become transparent to gamma rays

Posted by in categories: materials, quantum physics

“Iron nuclei can be made transparent to gamma rays that they would normally absorb using a new technique called “acoustically induced transparency” (AIT). This feat was achieved by physicists in the US and Russia, who vibrated an iron Mössbauer absorber using a piezoelectric transducer. The researchers believe the effect could help to control the emission of radiation from nuclei, allowing more accurate atomic clocks and other quantum optical devices to be created. The technique could even be used to slow the passage of gamma rays through a material.”


“Acoustically induced transparency” created by vibrating solid absorber.

May 12, 2020

Quantum brakes in molecules

Posted by in categories: particle physics, quantum physics

Physicists have measured the flight times of electrons emitted from a specific atom in a molecule upon excitation with laser light. This has enabled them to measure the influence of the molecule itself on the kinetics of emission.

Photoemission—the release of electrons in response to excitation by light—is one of the most fundamental processes in the microcosm. The kinetic energy of the emitted electron is characteristic for the atom concerned, and depends on the wavelength of the light employed. But how long does the process take? And does it always take the same amount of time, irrespective of whether the electron is emitted from an individual atom or from an atom that is part of a molecule? An international team of researchers led by laser physicists in the Laboratory for Attosecond Physics (LAP) at LMU Munich and the Max Planck Institute of Quantum Optics (MPQ) in Garching has now probed the influence of the molecule on photoemission time.

The theoretical description of photoemission in 1905 by Albert Einstein marked a breakthrough in , and the details of the process are of continuing interest in the world of science and beyond. How the motions of an elementary quantum particle such as the electron are affected within a molecular environment has a significant bearing on our understanding of the process of photoemission and the forces that hold molecules together.