Researchers at Chalmers University of Technology have succeeded in an experiment where they get an artificial atom to survive ten times longer than normal by positioning the atom in front of a mirror. The findings were recently published in the journal Nature Physics.
Tl;dr: Experimentalists are bringing increasingly massive systems into quantum states. They are now close to masses where they might be able to just measure what happens to the gravitational field.
Quantum effects of gravity are weak, so weak they are widely believed to not be measurable at all. Freeman Dyson indeed is fond of saying that a theory of quantum gravity is entirely unnecessary, arguing that we could never observe its effects anyway. Theorists of course disagree, and not just because they’re being paid to figure out the very theory Dyson deems unnecessary. Measurable or not, they search for a quantized version of gravity because the existing description of nature is not merely incomplete – it is far worse, it contains internal contradictions, meaning we know it is wrong.
Take the century-old double-slit experiment, the prime example for quantum behavior. A single electron that goes through the double-slit is able to interact with itself, as if it went through both slits at once. Its behavior is like that of a wave which overlaps with itself after passing an obstacle. And yet, when you measure the electron after it went through the slit it makes a dot on a screen, like a particle would. The wave-like behavior again shows up if one measures the distribution of many electrons that passed the slit. This and many other experiments demonstrate that the electron is neither a particle nor a wave – it is described by a wave-function from which we obtain a probability distribution, a formulation that is the core of quantum mechanics.
A team of physicists has proposed a way of teleporting energy over long distances. The technique, which is purely theoretical at this point, takes advantage of the strange quantum phenomenon of entanglement where two particles share the same existence.
The researchers, who work out of Tohoku University in Japan, and led by Masahiro Hotta,describe their proposal in the latest edition of Physical Review A. Their system exploits properties of squeezed light or vacuum states that should allow for the teleportation of information about an energy state. In turn, this teleported quantum energy could be made useable.
Unlike teleportation schemes as portrayed in Star Trek or The Fly, this type of teleportation describes entanglement experiments in which two entangled particles are joined despite no apparent connection between them. When a change happens to one particle, the same change happens to the other. Hence, the impression of teleportation. Physicists have conducted experiments using light, matter, and now, energy.
According to Hotta, a measurement on the first particle injects quantum energy into the system. Then, by carefully choosing the measurement to do on the second particle, it is possible to extract the original energy.
A new type of “quasiparticle” theorized by Caltech’s Gil Refael, a professor of theoretical physics and condensed matter theory, could help improve the efficiency of a wide range of photonic devices—technologies, such as optical amplifiers, solar photovoltaic cells, and even barcode scanners, which create, manipulate, or detect light.
If you’re on the east coast tonight, keep an eye on the sky between 7pm and 9pm: NASA is launching a test of some new tech that will include releasing colorful vapor tracers 130 miles above the Earth. It sounds like it’s going to be beautiful.
The vapors will be ejected from a sounding rocket launched from Wallops Flight Facility in Virginia. NASA explains that it has actually been injecting various vapor tracers into the atmosphere since the 1950s —these trails help scientists understand “the naturally occurring flows of ionized and neutral particles” in the upper atmosphere by injecting color tracers and tracking the flow across the sky.
Tonight, NASA says it’s ejecting four different payloads of a mix of barium and strontium, creating “a cloud with a mixture of blue-green and red color.” Here’s an example of a barium release provided by NASA; on the upper left you can see the barium’s “ionized component, which has become elongated along the Earth’s magnetic field lines.”
For decades, researchers have been trying to build a computer that harnesses the enormous potential of quantum mechanics. Now engineers from the University of New South Wales (UNSW) in Australia have overcome the final hurdle, by creating a quantum logic gate in silicon — the same material that today’s computer chips are made from.
The newly developed device allows two quantum bits — or qubits — to communicate and perform calculations together, which is a crucial requirement for quantum computers. Even better, the researchers have also worked out how to scale the technology up to millions of qubits, which means they now have the ability to build the world’s first quantum processor chip and, eventually, the first silicon-based quantum computer.
Right now, regular computer chips store information as binary bits, which are either in a 0 or 1 state. This system works well, but it means that there’s a finite amount of data that can be processed. Qubits, on the other hand, can be in the state of 0, 1, or both at the same time, which gives quantum computers unprecedented processing power… if we can work out how to build them.
Wow, first they create a real hoverboard, and now they’re on the road to creating a real lightsaber? Joy! wink
Killjoy physicists have long pointed out the sheer unlikelihood of building a working light saber. But now, they’ve taken a small step toward realizing the dream of Star Wars fans worldwide, by figuring out how to get photons to stick together like molecules in a super-chilled gas.
This latest work builds on prior experiments from 2013, when Harvard physicists first announced a new state of matter.
Photons don’t have mass and zip along at the speed of light, with no time to hang around in clumps. They also aren’t charged particles and thus don’t interact with each other much at all. They love to hang out with charged electrons, though. And that’s what’s going on here: the Harvard experiment created a special kind of medium in which photons act like charged particles with mass, enabling them to form molecules.
According to scientists photons can travel through time. They already have simulated directing quantum light particles to the past for the first time in the history. University of Queensland scientists learned that a simulation of two wormhole-travelling photons might interrelate; signifying hopping through time is conceivable at smallest scales. Their study might help to comprehend how time-travel could be conceivable in the quantum realm. PhD student Martin Ringbauer spoke to The Speaker: “For the first, ‘photon one’ would travel through a wormhole into the past and interact with its older version. In the second, ‘photon two’ travels through normal space-time but interacts with a photon that is stuck in a time-travelling loop through a wormhole, known as a closed timelike curve (CTC).”
Tim Ralph, UQ Physics Professor, said: “We used single photons to do this, but the time-travel was simulated by using a second photon to play the part of the past incarnation of the time travelling photon.”
Researchers from the Institute of General Physics of the Russian Academy of Sciences, the Institute of Bioorganic Chemistry of the Russian Academy of Sciences and MIPT have made an important step towards creating medical nanorobots. They discovered a way of enabling nano- and microparticles to produce logical calculations using a variety of biochemical reactions.
Details of their research project are given in the journal Nature Nanotechnology. It is the first experimental publication by an exclusively Russian team in one of the most cited scientific magazines in many years.
The paper draws on the idea of computing using biomolecules. In electronic circuits, for instance, logical connectives use current or voltage (if there is voltage, the result is 1, if there is none, it’s 0). In biochemical systems, the result can a given substance.
“If you were Luke Skywalker in Star Wars, and you carried a tiny green Jedi master on your back through the jungles of Dagobah for long enough, you could eventually raise your submerged X-wing out of the swamp just by using the Force.”
