Scholarly paper on building a time machine:
“Quantum teleportation through time-shifted AdS wormholes.
(Submitted on 30 Aug 2017)
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https://youtube.com/watch?v=BsKkqigDRmU
Trying to outrun the expiration of Moore’s Law.
As conventional microchip design reaches its limits, DARPA is pouring money into the specialty chips that might power tomorrow’s autonomous machines.
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While physicists have managed to wrap their minds around chaos theory in the macroscopic world, chaos also has its way at the quantum scale. And in many ways quantum chaos is even more perplexing than its large-scale counterpart.
Which is why it’s such a big deal that researchers have now presented a single equation that can predict how quantum chaos behaves.
This equation effectively explains the patterns within quantum chaos at the atomic level, and it could contribute to our understanding of everything from brain surgery to string theory.
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Quantum physics throws all the rules of classical physics out the window. In the quantum world, particles can pass through solid walls, be in two places at once, and communicate over an infinite distance. And, if a handful of physicists are right, they can affect the past just as easily as they affect the future. That’s a theory known as quantum retrocausality, and researchers have good reasons to believe it’s true.
Physicists from the University of Basel have developed a memory that can store photons. These quantum particles travel at the speed of light and are thus suitable for high-speed data transfer. The researchers were able to store them in an atomic vapor and read them out again later without altering their quantum mechanical properties too much. This memory technology is simple and fast and it could find application in a future quantum Internet. The journal Physical Review Letters has published the results.
Even today, fast data transfer in telecommunication networks employs short light pulses. Ultra broadband technology uses optical fiber links through which information can be transferred at the speed of light. At the receiver’s end, the transmitted information has to be stored quickly and without errors so that it can be processed further electronically on computers. To avoid transmission errors, each bit of information is encoded in relatively strong light pulses that each contain at least several hundreds of photons.
For several years, researchers all over the world have been working on operating such networks with single photons. Encoding one bit per photon is not only very efficient, but it also allows for a radically new form of information processing based on the laws of quantum physics. These laws allow a single photon to encode not only the states 0 or 1 of a classic bit, but also to encode a superposition of both states at the same time. Such quantum bits are the basis for quantum information processing that could make unconditionally secure communication and super fast quantum computers possible in the future. The ability to store and retrieve single photons from a quantum memory is a key element for these technologies, which is intensively investigated.
For the first time, researchers have sent a quantum-secured message containing more than one bit of information per photon through the air above a city. The demonstration showed that it could one day be practical to use high-capacity, free-space quantum communication to create a highly secure link between ground-based networks and satellites, a requirement for creating a global quantum encryption network.
Quantum encryption uses photons to encode information in the form of quantum bits. In its simplest form, known as 2D encryption, each photon encodes one bit: either a one or a zero. Scientists have shown that a single photon can encode even more information—a concept known as high-dimensional quantum encryption—but until now this has never been demonstrated with free-space optical communication in real-world conditions. With eight bits necessary to encode just one letter, for example, packing more information into each photon would significantly speed up data transmission.
“Our work is the first to send messages in a secure manner using high-dimensional quantum encryption in realistic city conditions, including turbulence,” said research team lead, Ebrahim Karimi, University of Ottawa, Canada. “The secure, free-space communication scheme we demonstrated could potentially link Earth with satellites, securely connect places where it is too expensive to install fiber, or be used for encrypted communication with a moving object, such as an airplane.”
