The Star Wars sequel trilogy is the upcoming third film trilogy in the American space opera franchise , created by George Lucas. It is being produced by Lucasfilm Ltd. and is to be the first films in the saga not to be distributed by 20th Century Fox.
The phenomenon is named after the curious feline in Alice in Wonderland, who vanishes leaving only its grin. Researchers took a beam of neutrons and separated them from their magnetic moment, like passengers and their baggage at airport security. They describe their feat in Nature Communications.
The same separation trick could in principle be performed with any property of any quantum object, say researchers from Vienna University of Technology. Their technique could have a useful application in metrology - helping to filter out disturbances during high-precision measurements of quantum systems.
The idea of a "quantum Cheshire Cat" was first proposed in 2010 by Dr Jeff Tollaksen from Chapman University, a co-author on this latest paper. In the world familiar to us, an object and its properties are always bound together. A rotating ball, for instance, cannot become separated from its spin.
The cat (the neutron) goes via the upper beam path, while its grin (the magnetic moment) goes via the lower. But quantum theory predicts that a particle (such as a photon or neutron) can become physically separated from one of its properties - such as its polarisation or its magnetic moment.
"We find the cat in one place, and its grin in another," as the researchers once put it. The feline analogy is a nod to Schrodinger's Cat - the infamous thought experiment in which a cat in a box is both alive and dead simultaneously - illustrating a quantum phenomenon known as superposition.
To prove that the Cheshire Cat is not just a cute theory, the researchers used an experimental set-up known as an interferometer, at the Institute Laue-Langevin (ILL) in Grenoble, France.
A neutron beam was passed through a silicon crystal, sending it down two different paths - like passengers and their luggage at airport security.
By applying filters and a technique known as "post-selection", they were able to detect the physical separation of the neutrons from their magnetic moment - as measured by the direction of their spin.
"The system behaves as if the neutrons go through one beam path, while their magnetic moment travels along the other," the researchers reported.
Many researchers believe that physics will not be complete until it can explain not just the behavior of space and time, but where these entities come from.
“Imagine waking up one day and realizing that you actually live inside a computer game,” says Mark Van Raamsdonk, describing what sounds like a pitch for a science-fiction film. But for Van Raamsdonk, a physicist at the University of British Columbia in Vancouver, Canada, this scenario is a way to think about reality. If it is true, he says, “everything around us — the whole three-dimensional physical world — is an illusion born from information encoded elsewhere, on a two-dimensional chip”. That would make our Universe, with its three spatial dimensions, a kind of hologram, projected from a substrate that exists only in lower dimensions.
This 'holographic principle' is strange even by the usual standards of theoretical physics. But Van Raamsdonk is one of a small band of researchers who think that the usual ideas are not yet strange enough. If nothing else, they say, neither of the two great pillars of modern physics — general relativity, which describes gravity as a curvature of space and time, and quantum mechanics, which governs the atomic realm — gives any account for the existence of space and time. Neither does string theory, which describes elementary threads of energy.
Van Raamsdonk and his colleagues are convinced that physics will not be complete until it can explain how space and time emerge from something more fundamental — a project that will require concepts at least as audacious as holography. They argue that such a radical reconceptualization of reality is the only way to explain what happens when the infinitely dense 'singularity' at the core of a black hole distorts the fabric of space-time beyond all recognition, or how researchers can unify atomic-level quantum theory and planet-level general relativity — a project that has resisted theorists' efforts for generations.
“All our experiences tell us we shouldn't have two dramatically different conceptions of reality — there must be one huge overarching theory,” says Abhay Ashtekar, a physicist at Pennsylvania State University in University Park.
Finding that one huge theory is a daunting challenge. Here, Nature explores some promising lines of attack — as well as some of the emerging ideas about how to test these concepts (see 'The fabric of reality').
"Human beings are works in progress that mistakenly think they're finished." Dan Gilbert shares recent research on a phenomenon he calls the "end of history illusion," where we somehow imagine that the person we are right now is the person we'll be for the rest of time. Hint: that's not the case.
In 2006 an Xavier High School English teacher named Ms. Lockwood gave her students an assignment: write a letter to a famous author. The instructions were to discuss the author’s work and ask for advice. Only one author responded -- Kurt Vonnegut -- (1922 – 2007). Here is what he said. Tiffany Willis is the founder…
The Long-Term Evolution Experiment, as the E. coli project is known, has surpassed 60,000 generations now, giving Lenski a deep data set from which to draw inferences about the interplay of contingency and convergence in evolution. Subtle changes in the bacteria’s DNA that make them larger and better able to proliferate in the flask have been relatively common across the groups. At the same time, Lenski has witnessed “striking” cases of contingency, in which one population did something completely different than the others. But as in convergence, he adds, these transformations weren’t entirely random.
It may seem as though all the famous writers have full-time writing jobs to which boost their chances of their novels selling and hitting the bookshelves. However, by looking through the authors etched in literary history, this is far from the case....
"We're all going to die -- and poems can help us live with that." In a charming and funny talk, literary critic Stephen Burt takes us on a lyrical journey with some of his favorite poets, all the way down to a line break and back up to the human urge to imagine.