'Solid light' could compute previously unsolvable problems - ScienceBlog.com

'Solid light' could compute previously unsolvable problems - ScienceBlog.com: To build their machine, the researchers created a structure made of superconducting materials that contains 100 billion atoms engineered to act as a single “artificial atom.” They placed the artificial atom close to a superconducting wire containing photons.
By the rules of quantum mechanics, the photons on the wire inherit some of the properties of the artificial atom – in a sense linking them. Normally photons do not interact with each other, but in this system the researchers are able to create new behavior in which the photons begin to interact in some ways like particles.
“We have used this blending together of the photons and the atom to artificially devise strong interactions among the photons,” said Darius Sadri, a postdoctoral researcher and one of the authors. “These interactions then lead to completely new collective behavior for light – akin to the phases of matter, like liquids and crystals, studied in condensed matter physics.”

IBM Scientists Show Blueprints for Brainlike Computing - MIT Technology Review

IBM Scientists Show Blueprints for Brainlike Computing - MIT Technology Review: “Programs” are written using special blueprints called corelets. Each corelet specifies the basic functioning of a network of neurosynaptic cores. Individual corelets can be linked into more and more complex structures—nested, Modha says, “like Russian dolls.”

The Curious Evolution of Artificial Life | MIT Technology Review

The Curious Evolution of Artificial Life | MIT Technology Review: He divides the history of Web-based artificial life into two periods: before and after 2005, a characterization that corresponds roughly with the emergence of Web 2.0 and the collaborative behaviors that it allows.

Is time moving forward or backward? Computers learn to spot the difference | Science/AAAS | News

Is time moving forward or backward? Computers learn to spot the difference | Science/AAAS | News: To find out, she and her collaborators broke down 180 YouTube videos into square patches of a few hundred pixels, which they further divided into four-by-four grids. Combining standard techniques for discovering objects in still photographs with motion detection algorithms, the researchers identified 4000 typical patterns of motion, or “flow words,” across a grid’s 16 cells. The gentle downward drifting of snowflakes, for example, would be one flow word. From those patterns, the team created flow word descriptions of each video along with three other versions—a time-reversed version, a mirror-image version, and a mirror-image and time-reversed version. Then, they made a computer program watch 120 of these clips, training it to identify which flow words best revealed whether a video ran forward or backward.

When they tested their program on the remaining 60 videos, the trained computers could correctly determine whether a video ran forward or backward 80% of the time...  A closer analysis found that flow words associated with divergence (water splashing outward as someone dives into a pool) or dissipation (a steam train’s exhaust spreading out in air) were especially good indicators of the direction in which time was moving.

This Could Be the First Animal to Live Entirely Inside a Computer

This Could Be the First Animal to Live Entirely Inside a Computer: "Our project is to simulate as much of the important physics — or biophysics — of the C. elegans as we can, and then compare against measurements from real worms. When we say simulation, we are specifically referring to writing computer programs that use equations from physics that are applied to what we know about the worm..."

"We are currently addressing the challenge of closing the 'brain-behavior loop' in C. elegans," he says. "In other words, through this simulation we want to understand how its proto-brain controls its muscles to move its body around an environment, and then how the environment is interpreted by the proto-brain. That means leaving aside reproduction or digestion or other internal functions for now until that first part is complete. Once we get there, we will move on to these other aspects.

New ‘switch’ could power quantum computing | MIT News Office

New ‘switch’ could power quantum computing | MIT News Office:  “We have demonstrated basically an atom can switch the phase of a photon. And the photon can switch the phase of an atom...”

In this case, the researchers used a laser to place a rubidium atom very close to the surface of a photonic crystal cavity, a structure of light. The atoms were placed no more than 100 or 200 nanometers — less than a wavelength of light — from the edge of the cavity. At such small distances, there is a strong attractive force between the atom and the surface of the light field, which the researchers used to trap the atom in place...

“In some sense, it was a big surprise how simple this solution was compared to the different techniques you might envision of getting the atoms there,” Vuletić says.

The Astounding Link Between the P≠NP Problem and the Quantum Nature of Universe — The Physics arXiv Blog — Medium

The Astounding Link Between the P≠NP Problem and the Quantum Nature of Universe — The Physics arXiv Blog — Medium: ...He says the key is to think of Schrodinger’s cat as a problem of computational complexity theory...

...He says there is an implicit assumption when physicists say that Schrödinger’s equation can describe macroscopic systems. This assumption is that the equations can be solved in a reasonable amount of time to produce an answer...

If P ≠ NP and there is no efficient algorithm for solving Schrödinger’s equation, then there is only one way of finding a solution, which is a brute force search...

So the number of elementary operations needed to exactly solve this equation would be equal to 2^10^24...

...this time scale is considerably shorter than the Planck timescale, which is roughly equal to 10^-43 seconds.

How An Ordinary Camera Phone Can Photograph Objects Hidden Behind Other Things — The Physics arXiv Blog — Medium

How An Ordinary Camera Phone Can Photograph Objects Hidden Behind Other Things — The Physics arXiv Blog — Medium: The trick here is to treat the data from each pixel as a separate image. The task then is to look for the correlation between each of these images, just as in the single-pixel imaging techniques...

And they even produce images using reflected light (as opposed to transmitting light). To prove this, these guys recorded the light from an object that was scattered off a wall covered in white paint.

Sure enough, the resulting image revealed the object, even though it was essentially around a corner from the camera.

Orbital computing: An amazing atomic-level tech for future computers | ExtremeTech

Orbital computing: An amazing atomic-level tech for future computers | ExtremeTech: He calls the idea “orbital computing” since the bit... would be the orbits of electrons around the nucleus of an atom. The goal is to be able to probe the electron clouds of single atoms using terahertz waves of just the right size.

In materials like these, the macroscopic properties (like conductance) are controlled mainly by electron orbits known as “d-orbitals.” The state of these d-orbitals can be readily observed with X-rays, and they can be controlled as easily as adjusting the temperature. But temperature or other gross manipulations are relatively slow ways to try to read or write data, compact bunches of T-rays does the trick much better.

First light-bending calculator designed with metamaterials - physics-math - 09 January 2014 - New Scientist

First light-bending calculator designed with metamaterials - physics-math - 09 January 2014 - New Scientist: The metamaterial computer works because light waves can draw mathematical curves in space, akin to a graph. In calculus, differentiation describes the slope of that curve at various points, while integration gives the area under the curve.

The team's metamaterial block can perform these calculations by modifying the light wave's profile. For example, if you shine a light wave describing a parabola (which corresponds to the equation y = x2) into a metamaterial that computes differentiation, it will come out the other side looking like a straight line described by y = 2x.siu

Supercomputers join search for 'cheapium'

Supercomputers join search for 'cheapium': The identification of the new platinum-group compounds hinges on databases and algorithms that Curtarolo and his group have spent years developing. Using theories about how atoms interact to model chemical structures from the ground up, Curtarolo and his group screened thousands of potential materials for high probabilities of stability. After nearly 40,000 calculations, the results identified 37 new binary alloys in the platinum-group metals, which include osmium, iridium ruthenium, rhodium, platinum and palladium.

These metals are prized for their catalytic properties, resistance to chemical corrosion and performance in high-temperature environments, among other properties.

New material for quantum computing discovered out of the blue

New material for quantum computing discovered out of the blue: The pigment, copper phthalocyanine (CuPc), which is similar to the light harvesting section of the chlorophyll molecule, is a low-cost organic semiconductor that is found in many household products...

...the electrons in CuPc can remain in 'superposition' ...  for surprisingly long times...

CuPc possesses many other attributes that could exploit the spin of electrons, rather than their charge, to store and process information which are highly desirable in a more conventional quantum technology. For example, the pigment strongly absorbs visible light and is easy to modify chemically and physically, so its magnetic and electrical properties can be controlled.

IBM unveils concept for a future brain-inspired 3D computer | KurzweilAI

IBM unveils concept for a future brain-inspired 3D computer | KurzweilAI: IBM has unveiled a prototype of a new brain-inspired computer powered by what it calls “electronic blood,” BBC News reports.

The firm says it is learning from nature by building computers fueled and cooled by a liquid, like our minds...

Its new “redox flow” system pumps an electrolyte “blood” through a computer, carrying power in and taking heat out.

First fully computer-designed superconductor | KurzweilAI

First fully computer-designed superconductor | KurzweilAI: Several years ago, Kolmogorov, then at Oxford University, began studying boron-based materials, which have complex structures and a wide range of applications. He developed an automated computational tool to identify previously unknown stable crystal structures. His “evolutionary” algorithm emulates nature, meaning it favors more stable materials among thousands of possibilities.

The search revealed two promising compounds in a common iron-boron system, which came as a surprise. Moreover, a graduate student’s calculations indicated that one of them should be a superconductor at an unusually high temperature of 15–20 Kelvin for the “conventional” type of superconductivity.

The First Carbon Nanotube Computer | MIT Technology Review

The First Carbon Nanotube Computer | MIT Technology Review: The carbon nanotube processor is comparable in capabilities to the Intel 4004, that company’s first microprocessor, which was released in 1971...
The nanotube processor is made up of 142 transistors, each of which contains carbon nanotubes that are about 10 to 200 nanometer long...
Theoretical work has... suggested that a carbon nanotube computer would be an order of magnitude more energy efficient than the best silicon computers.

Teleportation with engineered quantum systems

Teleportation with engineered quantum systems: "For the first time, the stunning process of quantum teleportation has now been used in a circuit to relay information from one corner of the sample to the other.
"What makes our work interesting is the system uses a circuit, much like modern computer chips.
"In our system the quantum information is stored in artificial structures called quantum bits, and you can even see them with your bare eyes...

This research indicates that questions relating to the physics of quantum communication can be addressed using electronic circuits at microwave frequencies.

Magnetic charge crystals imaged in artificial spin ice

Magnetic charge crystals imaged in artificial spin ice: In the honeycomb pattern, where three magnetic poles intersect, a net charge of north or south is forced at each vertex. The magnetic "monopole charge" at each vertex influences the magnetic "charge" of the surrounding vertices. The team was able to image the crystalline structure of the magnetic charges using magnetic force microscopy...

The research team's new annealing protocol—heating the material to a high temperature where their magnetic polarity is suppressed (here, about 550 degrees Celsius)—allows the nanomagnets to flip their polarity and freely interact. As the material cools, the nanomagnets are ordered according to the interactions of their poles at the vertices...

"This work demonstrates a direction in condensed matter physics that is quite opposite to what has been done in the last sixty years or so," said Nisoli. "Instead of imagining an emergent theoretical description to model the behavior of a nature-given material and validating it indirectly, we engineer materials of desired emergent properties that can be visualized directly."

First Atomic Level Simulation of a Whole Battery | MIT Technology Review

First Atomic Level Simulation of a Whole Battery | MIT Technology Review: The resulting simulations are small but impressive. Their nanobattery consists of 358 atoms, of which 118 make up the electrodes. The cathode is initially covered with a layer of 20 atoms with 39 positively ionised atoms dissolved in the electrolyte.

The calculation then proceeds in steps in which atoms can move and exchange charge as the system evolves. The entire simulation consists of some 10 million of these steps.

The results are remarkable because they actually reproduce the generic discharge curves of real macroscopic batteries. For example, a lower operating temperature reduces the effective capacity of the simulated battery. And most important of all, the simulation reproduces the way ordinary batteries wear out.

How to Save the Troubled Graphene Transistor | MIT Technology Review

How to Save the Troubled Graphene Transistor | MIT Technology Review:  “We intentionally avoid any attempt to artificially induce an energy band, which would make graphene “more-silicon-like”, they say. Instead they rely on a different phenomenon called negative resistance to create transistor-like behaviour.

Negative resistance is the counterintuitive phenomenon in which a current entering a material causes the voltage across it to drop...

Liu and co can build elementary XOR gates out of only three graphene field-effect transistors compared to the eight or more required using silicon. That translates into a significantly smaller area on a chip. What’s more, graphene transistors can operate at speeds of over 400 GHz.

Quantum teleportation approaches the computer chip | Matter & Energy | Science News

Quantum teleportation approaches the computer chip | Matter & Energy | Science News; Now physicist Andreas Wallraff at ETH Zurich and his team have created the first solid-state device, similar to a computer chip, that is capable of teleporting quantum information. The chip contains tiny circuits that each behave like an atom. The circuits are connected by millimeters-long transmission lines carrying microwave radiation, which entangles the circuits so that the properties of one affect the other. By programming a bit of quantum information into circuit A, Wallraff and his team changed the signal arriving at circuit B. They could then use that changed signal to determine the original properties of circuit A and transfer them to circuit B.

Most importantly, Wallraff’s teleportation system successfully transports information in nearly every attempt, and it can do it roughly 10,000 times per second, an unprecedented rate.