Menu

Blog

Archive for the ‘quantum physics’ category: Page 453

Jul 30, 2021

How Your Mind Really Works—Quantum Physics, Mayonnaise & the Mystery of Red

Posted by in category: quantum physics

Adapted from The Grand Biocentric Design, by Robert Lanza and Matej Pavsic, published by BenBella Books (2020).

You keep staring at the repair man. His words are starting to sink in. The fabulous and expensive generator you bought a few years ago to keep the lights burning during storms and power failures needs a major repair.

“A head gasket?”

Continue reading “How Your Mind Really Works—Quantum Physics, Mayonnaise & the Mystery of Red” »

Jul 29, 2021

Machine-learning technique used to pinpoint quantum errors

Posted by in categories: information science, quantum physics, robotics/AI

Researchers at the University of Sydney and quantum control startup Q-CTRL today announced a way to identify sources of error in quantum computers through machine learning, providing hardware developers the ability to pinpoint performance degradation with unprecedented accuracy and accelerate paths to useful quantum computers.

A joint scientific paper detailing the research, titled “Quantum Oscillator Noise Spectroscopy via Displaced Cat States,” has been published in the Physical Review Letters, the world’s premier physical science research journal and flagship publication of the American Physical Society (APS Physics).

Focused on reducing errors caused by environmental “noise”—the Achilles’ heel of —the University of Sydney team developed a technique to detect the tiniest deviations from the precise conditions needed to execute quantum algorithms using trapped ion and superconducting quantum computing hardware. These are the core technologies used by world-leading industrial quantum computing efforts at IBM, Google, Honeywell, IonQ, and others.

Jul 29, 2021

Chaotic electrons heed ‘limit’ in strange metals

Posted by in categories: energy, nanotechnology, quantum physics

Electrons in metals try to behave like obedient motorists, but they end up more like bumper cars. They may be reckless drivers, but a new Cornell-led study confirms this chaos has a limit established by the laws of quantum mechanics.

The team’s paper, “T-Linear Resistivity From an Isotropic Planckian Scattering Rate,” written in collaboration with researchers led by Louis Taillefer from the University of Sherbrooke in Canada, published July 28 in Nature. The paper’s lead author is Gael Grissonnanche, a postdoctoral fellow with the Kavli Institute at Cornell for Nanoscale Science.

Metals carry electric current when electrons all move together in tandem. In most metals, such as the copper and gold used for electrical wiring, the electrons try to avoid each other and flow in unison. However, in the case of certain “strange” metals, this harmony is broken and electrons dissipate energy by bouncing off each other at the fastest rate possible. The laws of quantum mechanics essentially play the role of an electron traffic cop, dictating an on how often these collisions can occur. Scientists previously observed this limit on the collision rate, also known as the “Planckian limit,” but there is no concrete theory that explains why the limit should exist, nor was it known how electrons reach this limit in . So Ramshaw and his collaborators set out to carefully measure it.

Jul 29, 2021

New exotic matter particle, a tetraquark, discovered

Posted by in categories: particle physics, quantum physics

Quarks are the fundamental building blocks from which matter is constructed. They combine to form hadrons, namely baryons, such as the proton and the neutron, which consist of three quarks, and mesons, which are formed as quark-antiquark pairs. In recent years a number of so-called exotic hadrons—particles with four or five quarks, instead of the conventional two or three—have been found. Today’s discovery is of a particularly unique exotic hadron, an exotic exotic hadron if you like.

The contains two and an up and a down antiquark. Several tetraquarks have been discovered in recent years (including one with two quarks and two charm antiquarks), but this is the first one that contains two charm quarks, without charm antiquarks to balance them. Physicists call this “open charm” (in this case, “double open charm”). Particles containing a charm quark and a charm antiquark have “hidden charm”—the charm quantum number for the whole particle adds up to zero, just like a positive and a negative electrical charge would do. Here the charm quantum number adds up to two, so it has twice the charm!

The content of Tcc+, has other interesting features besides being open charm. It is the first particle to be found that belongs to a class of tetraquarks with two heavy quarks and two light antiquarks. Such particles decay by transforming into a pair of mesons, each formed by one of the and one of the light antiquarks. According to some theoretical predictions, the mass of tetraquarks of this type should be very close to the sum of masses of the two mesons. Such proximity in mass makes the decay “difficult,” resulting in a longer lifetime of the particle, and indeed Tcc+, is the longest-lived exotic hadron found to date.

Jul 28, 2021

Dominance of γ-γ electron-positron pair creation in a plasma driven by high-intensity lasers

Posted by in category: quantum physics

Electron-positron pair generation from nonlinear quantum electrodynamics is predicted at high intensities that are, so far, beyond experimental capabilities. Here, simulations predict a high yield of positrons can be obtained from gamma-gamma photon collisions in the linear regime, using counter-propagating pulses and a microstructured target.

Jul 26, 2021

Qubit Spin Ice: Emergent Magnetic Monopoles Isolated Using Quantum-Annealing Computer

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

Project offers new step toward study of emergence, ‘materials by design,’ and future nanomagnets.

Using a D-Wave quantum-annealing computer as a testbed, scientists at Los Alamos National Laboratory have shown that it is possible to isolate so-called emergent magnetic monopoles, a class of quasiparticles, creating a new approach to developing “materials by design.”

“We wanted to study emergent magnetic monopoles by exploiting the collective dynamics of qubits,” said Cristiano Nisoli, a lead Los Alamos author of the study. “Magnetic monopoles, as elementary particles with only one magnetic pole, have been hypothesized by many, and famously by Dirac, but have proved elusive so far.”

Jul 24, 2021

Quantum control of a nanoparticle optically levitated in cryogenic free space

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

Quantum control of an optically levitated nanoparticle with a mass of just one femtogram is demonstrated in a cryogenic environment by feedback-cooling the motion of the particle to the quantum ground state.

Jul 24, 2021

Why AI will be so core to real-world quantum computing

Posted by in categories: business, quantum physics, robotics/AI

Be it large enterprises or small medium-sized businesses, Quantum Computing and Artificial Intelligence (AI) are two of the biggest buzzwords in IT today.

Jul 23, 2021

Quantum network is step towards ultrasecure internet

Posted by in categories: internet, quantum physics

Experiment connects three devices with entangled photons, demonstrating a key technique that could enable a future quantum internet. Experiment demonstrates a key technique that could enable a future quantum internet.

Jul 23, 2021

Physicists Show That a Quantum Particle Made of Light and Matter Can Be Dragged by a Current of Electrons

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

A pair of studies in Nature show that a quasiparticle, known as a plasmon polariton, can be pulled with and against a flow of electrons, a finding that could lead to more efficient ways of manipulating light at the nanoscale.