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Archive for the ‘quantum physics’ category: Page 601

Sep 18, 2019

Quantum Chemistry Breakthrough: DeepMind Uses Neural Networks to Tackle Schrödinger Equation

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

Wave function represents the quantum state of an atom, including the position and movement states of the nucleus and electrons. For decades researchers have struggled to determine the exact wave function when analyzing a normal chemical molecule system, which has its nuclear position fixed and electrons spinning. Fixing wave function has proven problematic even with help from the Schrödinger equation.

Previous research in this field used a Slater-Jastrow Ansatz application of quantum Monte Carlo (QMC) methods, which takes a linear combination of Slater determinants and adds the Jastrow multiplicative term to capture the close-range correlations.

Now, a group of DeepMind researchers have brought QMC to a higher level with the Fermionic Neural Network — or Fermi Net — a neural network with more flexibility and higher accuracy. Fermi Net takes the electron information of the molecules or chemical systems as inputs and outputs their estimated wave functions, which can then be used to determine the energy states of the input chemical systems.

Sep 18, 2019

FOLLOW-UP: What is the ‘zero-point energy’ (or ‘vacuum energy’) in quantum physics? Is it really possible that we could harness this energy?

Posted by in categories: quantum physics, space travel

This could make zero point energy teleportation for spaceships for near I instant object transfer.


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Sep 18, 2019

IBM opens Quantum Computation Center on Poughkeepsie campus

Posted by in categories: computing, finance, quantum physics

The previously “impossible to solve” problems for some of the biggest financial, technological and academic institutions will soon be solved in Poughkeepsie.

That’s according to IBM, which announced the opening of its first Quantum Computing Center on Wednesday, based on its Poughkeepsie campus.

Quantum computing is “nothing short of a revolution for how we are going to process information,” Director of IBM Research Dario Gil said. While computers have traditionally processed binary code — a collection of ones and zeroes — quantum computers, he said, process information in qubits, or quantum bits.

Sep 18, 2019

IBM will soon launch a 53-qubit quantum computer

Posted by in categories: computing, quantum physics

IBM continues to push its quantum computing efforts forward and today announced that it will soon make a 53-qubit quantum computer available to clients of its IBM Q Network. The new system, which is scheduled to go online in the middle of next month, will be the largest universal quantum computer available for external use yet.

The new machine will be part of IBM’s new Quantum Computation Center in New York State, which the company also announced today. The new center, which is essentially a data center for IBM’s quantum machines, will also feature five 20-qubit machines, but that number will grow to 14 within the next month. IBM promises a 95 percent service availability for its quantum machines.

IBM notes that the new 53-qubit system introduces a number of new techniques that enable the company to launch larger, more reliable systems for cloud deployments. It features more compact custom electronics for improves scaling and lower error rates, as well as a new processor design.

Sep 16, 2019

The first ever photograph of light as both a particle and wave

Posted by in categories: particle physics, quantum physics

(Phys.org)—Light behaves both as a particle and as a wave. Since the days of Einstein, scientists have been trying to directly observe both of these aspects of light at the same time. Now, scientists at EPFL have succeeded in capturing the first-ever snapshot of this dual behavior.

Quantum mechanics tells us that can behave simultaneously as a particle or a wave. However, there has never been an experiment able to capture both natures of light at the same time; the closest we have come is seeing either wave or particle, but always at different times. Taking a radically different experimental approach, EPFL scientists have now been able to take the first ever snapshot of light behaving both as a wave and as a particle. The breakthrough work is published in Nature Communications.

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Sep 16, 2019

Viewpoint: Surfing on a Wave of Quantum Chaos

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

A model based on Brownian motion describes the tsunami-like propagation of chaotic behavior in a system of quantum particles.

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In daily life, “chaos” describes anything messy. In physics, the term has a more specific meaning: It refers to systems that, while subject to deterministic laws, are totally unpredictable because of an exponential sensitivity to initial conditions—think of the butterfly flapping its wings and causing a distant tornado. But how does the chaos observed in the classical, macroscopic world emerge from the quantum-mechanical laws that govern the microscopic world? A recently proposed explanation invokes quantum “information scrambling” [1, 3], in which information gets rapidly dispersed into quantum correlations among the particles of a system. This scrambling is a memory-loss mechanism that can cause the unpredictability of chaos. Developing a theory that fully describes information scrambling remains, however, a daunting task.

Sep 16, 2019

Researchers advance noise cancelling for quantum computers

Posted by in categories: computing, quantum physics

A team from Dartmouth College and MIT has designed and conducted the first lab test to successfully detect and characterize a class of complex, “non-Gaussian” noise processes that are routinely encountered in superconducting quantum computing systems.

The characterization of non-Gaussian noise in superconducting quantum bits is a critical step toward making these systems more precise.

The joint study, published in Nature Communications, could help accelerate the realization of systems. The experiment was based on earlier conducted at Dartmouth and published in Physical Review Letters in 2016.

Sep 15, 2019

F-35 and F-22 RIP?: Researchers in Austria Have Created a Working Quantum Radar

Posted by in categories: military, quantum physics

RIP F-22 and F-35?

Sep 14, 2019

Testing quantum mechanics in a non-inertial reference frame using a rotating interferometer

Posted by in categories: electronics, quantum physics

A team of researchers from the University of Glasgow and the University of Southampton has devised a novel way to test quantum mechanics in a non-inertial reference frame by using a rotating interferometer. In their paper published in the journal Physical Review Letters, the group describes studying the Hong-Ou-Mandel interference using fiber coils on a rotating disk, and what they found.

As physicists struggle with the problem of uniting and , they devise new ways to both. In this new effort, the researchers noted that the two theories are consistent under some conditions—such as when gravity is very weak, or when modest acceleration is involved. In their experiment, they chose to test the Hong-Ou-Mandel interference, in which entangled photons are sent on different paths along a circular track—one clockwise, the other counterclockwise. Theory suggests that when such entangled photons are reunited, they should bunch together and move toward one detector or the other. Conversely, non-entangled photons should travel toward either detector randomly.

In their experiment, the researchers set fiber cables on a rotating disk along with sensors for reading where the photons went after passing through the cables. They then sent a stream of entangled photons through the fiber cables (one clockwise, the other counterclockwise) and noted how they behaved as the disk was rotated—a means of applying a non-inertial reference frame. The researchers report that, as expected, the entangled photons did, indeed, bunch up and march off to a sensor together after being reunited with a beam splitter. More importantly, they noted that applying a non-inertial reference frame resulted in one of a pair of photons arriving a little later than the other, which in turn had an impact on the bunching signals the team recorded.

Sep 13, 2019

Solving the Schrödinger equation with deep learning

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

The code used below is on GitHub.

In this project, we’ll be solving a problem familiar to any physics undergrad — using the Schrödinger equation to find the quantum ground state of a particle in a 1-dimensional box with a potential. However, we’re going to tackle this old standby with a new method: deep learning. Specifically, we’ll use the TensorFlow package to set up a neural network and then train it on random potential functions and their numerically calculated solutions.

Why reinvent the wheel (ground state)? Sure, it’s fun to see a new tool added to the physics problem-solving toolkit, and I needed the practice with TensorFlow. But there’s a far more compelling answer. We know basically everything there is to know about this topic already. The neural network, however, doesn’t know any physics. Crudely speaking, it just finds patterns. Suppose we examine the relative strength of connections between input neurons and output. The structure therein could give us some insight into how the universe “thinks” about this problem. Later, we can apply deep learning to a physics problem where the underlying theory is unknown. By looking at the innards of that neural network, we might learn something new about fundamental physical principles that would otherwise remain obscured from our view. Therein lies the true power of this approach: peering into the mind of the universe itself.