21. Entanglement Swapping between Photons that have Never Coexisted

Entanglement Between Photons that have Never Coexisted E. Megidish, A. Halevy, T. Shacham, T. Dvir, L. Dovrat, H. S. Eisenberg (Submitted on 19 Sep 2012) FULL TEXT PDF The role of the timing and order of quantum measurements is not just a fundamental question of quantum mechanics, but also a puzzling one. Any part of a quantum system that has finished evolving, can be measured immediately or saved for later, without affecting the final results, regardless of the continued evolution of the rest of the system. In addition, the non-locality of quantum mechanics, as manifested by entanglement, does not apply only to particles with spatial separation, but also with temporal separation. Here we demonstrate these principles by generating and fully characterizing an entangled pair of photons that never coexisted. Using entanglement swapping between two temporally separated photon pairs we entangle one photon from the first pair with another photon from the second pair. The first photon was detected even before the other was created. The observed quantum correlations manifest the non-locality of quantum mechanics in spacetime.

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22. Psychic Ops

Earlier this month, Prudence Calabrese, a West Coast psychic, flew into New York on business. She had two meetings: One was a catered sushi lunch at an uptown hedge fund that had hired her, for about $20,000, to predict this year's profit outlook. ("Their investors will be very happy.") The second, she says, was with agents from the FBI. During the Cold War, the Pentagon spent millions training "remote viewers" to spy on Russian military targets. (The Soviets, of course, had their own psychics.) The program, called Stargate, was very controversial, very X-Files, and until funding was cut in 1995, completely classified.

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23. Correcting the past: failures to replicate ψ

J Pers Soc Psychol. 2012 Dec;103(6):933-48. doi: 10.1037/a0029709. Epub 2012 Aug 27. Correcting the past: failures to replicate ψ. Galak J, Leboeuf RA, Nelson LD, Simmons JP. Tepper School of Business, Carnegie Mellon University, 5000 Forbes Avenue, Office 381-D, Pittsburgh, PA 15213, USA. jgalak@cmu.edu Abstract Across 7 experiments (N = 3,289), we replicate the procedure of Experiments 8 and 9 from Bem (2011), which had originally demonstrated retroactive facilitation of recall. We failed to replicate that finding. We further conduct a meta-analysis of all replication attempts of these experiments and find that the average effect size (d = 0.04) is no different from 0. We discuss some reasons for differences between the results in this article and those presented in Bem (2011).

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24. Italy earhquake premonitions

Name: perispri: Foresee: I am in Italy, began to break down historic church bells ringing noise when I look back I see the destruction of the bridge is a suspension bridge on the bridge before the bridge that keeps the feet then he did not understand earhquake, road crashes. 01 November 2010 Your name: Your love: Foresee: Italy? name blooded ... Image of a cloud of dust .. italy red letter?? 30.07.2011 Your name: Your love: Foresee: rain. A dark, misty weather .. the wind .. the sounds of children crying .. earthquake, descending the stairs with the baby in her arms painted black with blue-haired woman ... ITALY-ENGLAND-IZMIR .. names ..! 20.04.2010 Name: Ezoterica: Dream Foresee: June 4, Saturday morning, I saw an image: Very close to the South of Italy or South Asia at a time (a long boot image of the country's south, such as geological). A violent earthquake .. 04.06.2010

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25. Is Belief In Telepathy Unscientific?

Rigorous experiments seem to suggest that ESP and mental telepathy are real, yet these phenomena are rejected as hoaxes by mainstream science, because belief in mind reading would contradict the most basic laws of our understanding of reality. Or would it? Via Reality Sandwich, Chris Carter argues that telepathy and quantum physics go hand-in-hand:

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26. Twitter experiment casts doubt on psychic 'remote viewing'

More than 7,000 people took part in the study designed to test people's ability to "see" distant locations. During the 1970s the CIA spent £12.5 million looking into remote viewing with a view to conducting "psychic spying" missions against the Soviet Union. But the "Twitter" experiment led by psychologist Professor Richard Wiseman, from the University of Hertfordshire, found no evidence that such an ability exists. During the study, the first to be carried out via the instant messaging service, Prof Wiseman travelled to four target locations in the UK and asked participants to "Tweet" their thoughts and impressions about the spot he was visiting. olunteers were then messaged with the address of a website on which they could see photographs of five locations – the target location and four decoys.

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27. Photon reaches from beyond the grave in quantum trick

EINSTEIN mockingly called it "spooky action at a distance": the finding that quantum particles can influence each other regardless of how far apart they are. We can only imagine his horror at a new experiment that extends the idea to time by entangling a pair of photons that never coexisted. As well as expanding the reach of quantum theory's baffling implications, the experiment could improve long-distance cryptography. At the heart of the phenomena is entanglement, in which the quantum states of two entities become linked. The implications of this for spatially distant particles stumped even Einstein, but things got still stranger last year. Joachim von Zanthier of the University of Erlangen-Nuremberg in Germany and his colleagues showed that, in principle, entanglement could also work for particles that have never existed at the same time (Optics Letters, doi.org/bdwpsj). Now Hagai Eisenberg of the Hebrew University of Jerusalem in Israel and colleagues have done the experiment, via a process called an entanglement swap. If you have two pairs of entangled photons, taking one photon from each pair and entangling them disengages the two original pairs, and creates a second, fresh entanglement between the two, left out photons. Eisenberg's team used the swap to entangle a photon with one that no longer existed. They started with an entangled pair of photons, 1 and 2, and then measured the quantum state of photon 1, which destroys the particle. Photon 2, however, lived on and, about 100 nanoseconds later, the team created a new pair of entangled photons, 3 and 4. When the team entangled photon 2 with newborn photon 3, photon 4 also became entangled with photon 1 - even though 1 was by then "dead" (see diagram). The team knew 4 was entangled with 1 by measuring 4's state, which depended on the states measured for 1, 2 and 3 (arxiv.org/abs/1209.4191v1). "Without the idea of entanglement, you cannot explain it," says von Zanthier, who was not involved in the latest experiment. "The future photon, which is not born, is strongly influenced by a photon that is already dead." The result could boost quantum cryptography, in which entangled photons are used to transmit a secret key for ciphers. Entanglement makes the process secure because if a photon is intercepted, its partner registers this, allowing the key to be ditched. Entanglement swapping can enable the process over enormous distances. Take an entangled pair, 1 and 2, created in London. Photon 2 can be sent to Paris, where an entanglement swap with another pair, 3 and 4, takes place. Photon 4 is now entangled with 1 - still in London - and can then be sent to Berlin. Quantum communication between London and Berlin is now possible, even though no single photon has travelled that distance. The process can be extended by further swaps, all the way to Beijing, say. But currently, London would have to hold on to its photons until the chain is complete - which gets trickier as the total distance increases. The new experiment shows that London can measure its photons well before Beijing's even exist. "London can already start working," says Johannes Kofler of the Max Planck Institute of Quantum Optics in Garching, Germany. "That's cool."

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28. City workers turn to psychics for advice

Bankers and accountants who used to put their faith in spreadsheets and complex formulas are now turning to clairvoyants for guidance. Many have even started taking in job offers and contracts to be analysed. The British Astrological and Psychic Society (BAPS) said it had witnessed a dramatic increase in the demand for readings in the last year – particularly in the last three months. Websites such as thepsychicsociety.co.uk and psychics.co.uk, which also offer psychic readings over the phone, have also reported a significant increase in enquiries. "I've definitely noticed a new trend," said Jayne Wallace, a clairvoyant who works in the Selfridges department store, in central London. "We're getting lots of city workers – particularly men coming in for readings. 

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29. Mad Genius: Study Suggests Link Between Psychosis And Creativity

Vincent van Gogh cut off his ear. Sylvia Plath stuck her head in the oven. History teems with examples of great artists acting in very peculiar ways. Were these artists simply mad or brilliant? According to new research reported in Psychological Science, a journal of the Association for Psychological Science, maybe both.

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30. Possibility of Cloning Quantum Information from the Past

Dec. 8, 2013 — Popular television shows such as "Doctor Who" have brought the idea of time travel into the vernacular of popular culture. But problem of time travel is even more complicated than one might think. LSU's Mark Wilde has shown that it would theoretically be possible for time travelers to copy quantum data from the past.   It all started when David Deutsch, a pioneer of quantum computing and a physicist at Oxford, came up with a simplified model of time travel to deal with the paradoxes that would occur if one could travel back in time. For example, would it be possible to travel back in time to kill one's grandfather? In the Grandfather paradox, a time traveler faces the problem that if he kills his grandfather back in time, then he himself is never born, and consequently is unable to travel through time to kill his grandfather, and so on. Some theorists have used this paradox to argue that it is actually impossible to change the past. "The question is, how would you have existed in the first place to go back in time and kill your grandfather?" said Mark Wilde, an LSU assistant professor with a joint appointment in the Department of Physics and Astronomy and with the Center for Computation and Technology, or CCT. Deutsch solved the Grandfather paradox originally using a slight change to quantum theory, proposing that you could change the past as long as you did so in a self-consistent manner. "Meaning that, if you kill your grandfather, you do it with only probability one-half," Wilde said. "Then, he's dead with probability one-half, and you are not born with probability one-half, but the opposite is a fair chance. You could have existed with probability one-half to go back and kill your grandfather." But the Grandfather paradox is not the only complication with time travel. Another problem is the no-cloning theorem, or the no "subatomic Xerox-machine" theorem, known since 1982. This theorem, which is related to the fact that one cannot copy quantum data at will, is a consequence of Heisenberg's famous Uncertainty Principle, by which one can measure either the position of a particle or its momentum, but not both with unlimited accuracy. According to the Uncertainty Principle, it is thus impossible to have a subatomic Xerox-machine that would take one particle and spit out two particles with the same position and momentum -- because then you would know too much about both particles at once. "We can always look at a paper, and then copy the words on it. That's what we call copying classical data," Wilde said. "But you can't arbitrarily copy quantum data, unless it takes the special form of classical data. This no-cloning theorem is a fundamental part of quantum mechanics -- it helps us reason how to process quantum data. If you can't copy data, then you have to think of everything in a very different way." But what if a Deutschian closed timelike curve did allow for copying of quantum data to many different points in space? According to Wilde, Deutsch suggested in his late 20th century paper that it should be possible to violate the fundamental no-cloning theorem of quantum mechanics. Now, Wilde and collaborators at the University of Southern California and the Autonomous University of Barcelona have advanced Deutsch's 1991 work with a recent paper in Physical Review Letters. The new approach allows for a particle, or a time traveler, to make multiple loops back in time -- something like Bruce Willis' travels in the Hollywood film "Looper." "That is, at certain locations in spacetime, there are wormholes such that, if you jump in, you'll emerge at some point in the past," Wilde said. "To the best of our knowledge, these time loops are not ruled out by the laws of physics. But there are strange consequences for quantum information processing if their behavior is dictated by Deutsch's model." A single looping path back in time, a time spiral of sorts, behaving according to Deutsch's model, for example, would have to allow for a particle entering the loop to remain the same each time it passed through a particular point in time. In other words, the particle would need to maintain self-consistency as it looped back in time. "In some sense, this already allows for copying of the particle's data at many different points in space," Wilde said, "because you are sending the particle back many times. It's like you have multiple versions of the particle available at the same time. You can then attempt to read out more copies of the particle, but the thing is, if you try to do so as the particle loops back in time, then you change the past." To be consistent with Deutsch's model, which holds that you can only change the past as long as you can do it in a self-consistent manner, Wilde and colleagues had to come up with a solution that would allow for a looping curve back in time, and copying of quantum data based on a time traveling particle, without disturbing the past. "That was the major breakthrough, to figure out what could happen at the beginning of this time loop to enable us to effectively read out many copies of the data without disturbing the past," Wilde said. "It just worked." However, there is still some controversy over interpretations of the new approach, Wilde said. In one instance, the new approach may actually point to problems in Deutsch's original closed timelike curve model. "If quantum mechanics gets modified in such a way that we've never observed should happen, it may be evidence that we should question Deutsch's model," Wilde said. "We really believe that quantum mechanics is true, at this point. And most people believe in a principle called Unitarity in quantum mechanics. But with our new model, we've shown that you can essentially violate something that is a direct consequence of Unitarity. To me, this is an indication that something weird is going on with Deutsch's model. However, there might be some way of modifying the model in such a way that we don't violate the no-cloning theorem." Other researchers argue that Wilde's approach wouldn't actually allow for copying quantum data from an unknown particle state entering the time loop because nature would already "know" what the particle looked like, as it had traveled back in time many times before. But whether or not the no-cloning theorem can truly be violated as Wilde's new approach suggests, the consequences of being able to copy quantum data from the past are significant. Systems for secure Internet communications, for example, will likely soon rely on quantum security protocols that could be broken or "hacked" if Wilde's looping time travel methods were correct. "If an adversary, if a malicious person, were to have access to these time loops, then they could break the security of quantum key distribution," Wilde said. "That's one way of interpreting it. But it's a very strong practical implication because the big push of quantum communication is this secure way of communicating. We believe that this is the strongest form of encryption that is out there because it's based on physical principles." Today, when you log into your Gmail or Facebook, your password and information encryption is not based on physical principles of quantum mechanical security, but rather on the computational assumption that it is very difficult for "hackers" to factor mathematical products of prime numbers, for example. But physicists and computer scientists are working on securing critical and sensitive communications using the principles of quantum mechanics. Such encryption is believed to be unbreakable -- that is, as long as hackers don't have access to Wilde's looping closed timelike curves. "This ability to copy quantum information freely would turn quantum theory into an effectively classical theory in which, for example, classical data thought to be secured by quantum cryptography would no longer be safe," Wilde said. "It seems like there should be a revision to Deutsch's model which would simultaneously resolve the various time travel paradoxes but not lead to such striking consequences for quantum information processing. However, no one yet has offered a model that meets these two requirements. This is the subject of open research."

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