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The Quantum Cheshire Cat: Can neutrons be located at a different place than their own spin? Jul 29, 2014 Enlarge The basic idea of the Quantum Cheshire Cat: In an interferometer, an object is separated from one if its properties -- like a cat, moving on a different path than its own grin. Credit: TU Vienna / Leon Filter The Cheshire Cat featured in Lewis Caroll's novel "Alice in Wonderland" is a remarkable creature: it disappears, leaving its grin behind. Can an object be separated from its properties? It is possible in the quantum world. In an experiment, neutrons travel...

When he died on September 7, 2012, theoretical physicist Claud W. Lovelace left behind a house filled with parakeets. With no family or close companions, the eccentric Rutgers professor loved to be surrounded by his colorful fine-feathered friends and listen to classical music as he contemplated the nuances of unified field theory. A loner not particularly close to his colleagues, members of the Physics and Astronomy department were astounded and delighted when he willed his entire fortune of $1.5 million to it. The funds were used to help establish endowed positions in practical fields of physics, a far cry from...

Until yesterday, every physicist was laughing at this engine and its inventor, Roger Shawyer. It's called the EmDrive and everyone said it was impossible because it goes against classical mechanics. But the fact is that the quantum vacuum plasma thruster works and scientists can't explain why. Shawyer's engine is extremely light and simple. It provides a thrust by "bouncing microwaves around in a closed container." The microwaves are generated using electricity that can be provided by solar energy. No propellant is necessary, which means that this thrusters can work forever unless a hardware failure occurs. If real, this would be...

Let me geek out on you (I love science) and explain to you the science (I love science) and why this had previously been confined to the pages of science fiction (I am a nerd; and oh Dear Sweet Bunsen-Burner Lighting Lord, do I love science). So it's a pretty firmly established principle that every act causes, and requires, an equal and opposite reaction. If I understand this right (did I mention I love science?), this means that any space vessel will have to carry with it an enormous amount of reaction mass. You can't -- we think, or thought...

Scientists are working to bring the multiverse hypothesis, which to some sounds like a fanciful tale, firmly into the realm of testable science. Never mind the Big Bang; in the beginning was the vacuum. The vacuum simmered with energy (variously called dark energy, vacuum energy, the inflation field, or the Higgs field). Like water in a pot, this high energy began to evaporate -- bubbles formed.

Nearly three hundred years since his death, Isaac Newton is as much a myth as a man. The mythical Newton abounds in contradictions; he is a semi-divine genius and a mad alchemist, a somber and solitary thinker and a passionate religious heretic. Myths usually have an element of truth to them but how many Newtonian varieties are true? Here are ten of the most common, debunked or confirmed by the evidence of his own private papers, kept hidden for centuries and now freely available online. 10. Newton was a heretic who had to keep his religious beliefs secret. True. While...

There is a "missing light crisis" taking place in the universe with a huge deficit on what there should be and what there actually is, astronomers have said. In a statement, experts from the Carnegie Institution for Science said "something is amiss in the universe" with 80% of the light missing. Lead author of the study Juna Kollmeier said: "It's as if you're in a big, brightly-lit room, but you look around and see only a few 40-watt lightbulbs. Where is all that light coming from? It's missing from our census." Published in Astrophysical Journal Letters, scientists found that the...

University of Queensland researchers say photons can move through time A simulation of two wormhole-travelling photons found they could interact This suggests, at the smallest scales, jumping through time is possible The experiment could solve some famous theories that 'prevent' time travel But whether this will be possible on a larger scale remains to be seen If a time traveller went back in time and stopped their own grandparents from meeting, would they prevent their own birth? That’s the crux of an infamous theory known as the 'grandfather paradox', which is often said to mean time travel is impossible -...

The University of Maryland physicist believes the delay could have been because the light was in fact slowed as it travelled due to something known as 'vacuum polarisation'. During this phenomenon, photons break down to something known as ‘positrons’ and electrons for a split second. before combining together again. When they split, quantum mechanics creates a gravitational potential between the pair of ‘virtual’ particles. Dr Franson argues that the process might have a gradual impact on the speed of the photon, meaning that over 168,000 light years, the photons may have suffered a near five-hour delay. If the physicist is...

Albert Einstein once told a friend that quantum mechanics doesn't hold water in his scientific world view because "physics should represent a reality in time and space, free from spooky actions at a distance." That spooky action at a distance is entanglement, a quantum phenomenon in which two particles, separated by any amount of distance, can instantaneously affect one another as if part of a unified system. Now, scientists have successfully hijacked that quantum weirdness -- doing so reliably for the first time -- to produce what many sci-fi fans have long dreamt up: teleportation. No, not beaming humans aboard...

Up to this point, the tunneling process only involved one particle tunneling through a single barrier. Hanns-Christoph Nägerl and a team of researchers at the Institute for Experimental Physics of the University of Innsbruck, in Innsbruck, Austria recently learned of a process for quantum particles to pass through as many as five different barriers simultaneously via an effect called Bose enhancement. They created what they call “a physical quantum simulator” that can imitate other quantum systems. They cooled cesium atoms to almost absolute zero or -459.67 degrees F. They next put the atoms in an essential optical lattice created with...

Sometimes it takes a second look — or even more — at an astronomical object to understand what’s going on. This is what happened after astronomers obtained this image of NGC 5548 using the Hubble Space Telescope in 2013. While crunching the data, they saw some gas moving around the galaxy in a way that they did not understand. From the supermassive black hole embedded in the galaxy’s heart, the researchers detected gas moving outward quite quickly — blocking about 90% of the X-rays being emitted from the black hole, a common feature of objects of this type. So, astronomers...

American Antigravity interviewed Eugene Podkletnov to discuss recent (2004 to 2013) experimental antigravity research in gravity modification and superconductors. For nearly two decades Dr. Podkletnov has been researching the link between gravitation and high-temperature superconductors, and just recently published the peer-review results of new experiments he’s conducted to measure the speed of a force-beam projected by a stationary superconducting apparatus he’s developed. Podkletnov is well-known for his experiments involving YBCO superconductors, which produced a gravity-shielding effect that was investigated by NASA and has been the subject of many peer-review papers. He describes continuing his experiments in this area, and indicates...

Over the past week there has been quite a buzz in the scientific community over a Dutch experiment reliably transmitting data instantly between two electrons via quantum entanglement. While many reports are sensationalizing the discovery, referring to it as a breakthrough in ‘teleportation’, there’s something almost as exciting as physical transportation already proven possible in the experiment: instant communication! While scientists have reached a 3-meter(or 10-foot) range with a 100% success rate, worldwide implementation would revolutionize communication. Instant text messages, infinitely scalable internet bandwidth, and sub-millisecond(or even sub-measurable) latency. Even now, our fastest long-distance communication efforts are too slow to...

The astronomers who this spring announced that they had evidence of primordial gravitational waves jumped the gun because they did not take into proper account a confounding effect of galactic dust, two new analyses suggest. Although further observations may yet find the signal to emerge from the noise, independent experts now say they no longer believe that the original data constituted significant evidence. Researchers said in March that they had found a faint twisting pattern in the polarization of the cosmic microwave background (CMB), the Big Bang’s afterglow, using a South Pole-based radio telescope called BICEP2. This pattern, they said,...

Imperial College London physicists have discovered how to create matter from light - a feat thought impossible when the idea was first theorised 80 years ago. In just one day over several cups of coffee in a tiny office in Imperial's Blackett Physics Laboratory, three physicists worked out a relatively simple way to physically prove a theory first devised by scientists Breit and Wheeler in 1934.Breit and Wheeler suggested that it should be possible to turn light into matter by smashing together only two particles of light (photons), to create an electron and a positron – the simplest method of...

The aurora is more than just a breathtaking display of light. It may also hold the secret of a magnetic phenomenon related to the nuclear fusion powering the sun. This secret could even help create nuclear fusion in the lab, says a team of researchers. Nuclear fusion is a reaction that combines the nuclei of two atoms into one. The process powers stars, but getting a self-sustained fusion reaction going on Earth is very difficult, and has so far eluded scientists. For example, in February, researchers at the Lawrence Livermore Laboratory in California made headlines when they managed to spur...

The most powerful particle accelerator in the world, the Large Hadron Collider, has not yet created any black holes as some have feared, researchers say. Even if this atom smasher does create black holes, there is no danger of those black holes destroying Earth, added scientists of the new study published online March 5 in the journal Physical Review Letters.

Nearly 90 years after Werner Heisenberg pioneered his uncertainty principle, a group of researchers from three countries has provided substantial new insight into this fundamental tenet of quantum physics with the first rigorous formulation supporting the uncertainty principle as Heisenberg envisioned it. In the Journal of Mathematical Physics, the researchers reports a new way of defining measurement errors that is applicable in the quantum domain and enables a precise characterization of the fundamental limits of the information accessible in quantum experiments. Quantum mechanics requires that we devise approximate joint measurements because the theory itself prohibits simultaneous ideal measurements of position...

21 Image Caption: Artist's impression of a binary supermassive black hole system. Credit: ESA - C. Carreau ESAA pair of supermassive black holes in orbit around one another have been spotted by XMM-Newton. This is the first time such a pair have been seen in an ordinary galaxy. They were discovered because they ripped apart a star when the space observatory happened to be looking in their direction.Most massive galaxies in the Universe are thought to harbor at least one supermassive black hole at their center. Two supermassive black holes are the smoking gun that the galaxy has merged...