There are so many things we don’t yet understand about quantum physics, and it seems like the things we don’t get are far outpacing the things we do. A new experiment conducted at the University of Vienna demonstrates that perfectly. In it, cause and effect seem to swap places  – at least, from the point of view of a “traditional” world view.

The experiment involves two pairs of particles, either entangled or not. One person decides whether the particles are entangled, and a pair of people observes the particles to see if they are entangled. But the kicker: the measurement takes place before the decision, and it’s always accurate. The team doing the research calls it “quantum steering into the past,” which is kind of a nice way of saying that the world is an amazing, freaky place that we’ve probably been looking at all wrong this whole time.

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It’s a simple fact that computers generate heat as they work. While part of this is certainly due to the engineering of the machines, another part has to do with fundamental physics: processing information generates heat. In a mind-blowing new paper, a group of researchers describe how data deletion can actually have a cooling effect thanks to the mysterious phenomenon of quantum entanglement. In the scientific journal Nature, the team describes how supercomputers, which often experience limited performance due to their heat generation, could benefit from quantum cooling.

The actual mechanism of the theory might be a little hard to follow, but it all centers on the observer and on two different definitions of entropy. In thermodynamics, entropy refers to the disorder present in a system. In information theory, entropy is a measure of information density. The theory described in this new study basically states that both terms are describing the same thing, which is essentially a lack of knowledge.

Objects don’t possess entropy; observers do. So according to this theory, if two observers delete the same amount of data in memory and one has more knowledge of the data, that user perceives lower entropy and completes the deletion using less energy than the uninformed observer. An observer with perfect “classical” (as in classical physics) knowledge of the data could delete it with zero energy. But if observer and data shared quantum entanglement, the observer would have greater than complete knowledge and an entropy of less than zero. The result is that the deletion actually results in removing heat from the system. Of course, the quantum cooling theory is just that: a theory. It has yet to be tested, but conceptually it is entirely possible that quantum entanglement will help cool our supercomputers.

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We have known for quite some time that quantum storage and quantum communication could vastly improve our current communications technology, but it’s not an easy pursuit. Getting photons to do what we want them to do is even harder than you might expect, so until now quantum communication has been more or less an exercise in educated guessing. Lately, researchers at the University of Calgary along with partners at the German University of Paderborn have been pushing quantum networks closer and closer to reality. They figured out that by “doping” a lithium niobate crystal with rare earth ions and chilling it to -454 Fahrenheit, the crystals can store and retrieve information in entangled photons. It’s quantum memory, the first step toward super-fast and super-secure quantum computers.

Quantum computers make use of that “freaky” quantum phenomenon of entanglement, a fundamental connection between two or more photons that means whatever changes happen to one happen to all other entangled photons. In this study, researchers used the precisely-tuned crystals to produce entangled copies of photons. The crystals and the information-containing photons can be stored and retrieved at will, much in the way that bytes of information are stored in a conventional computer. In other words, information is more or less being stored on a crystal, making quantum networks seem nearly within our reach at last. Similar results were found in a separate study at the University of Geneva, suggesting that the teams are onto something provable.

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We may not be able to send scientists gallivanting around in time to right the wrongs of the past (yet), but physicists at the University of Queensland in Australia have discovered that the peculiar quantum phenomenon of entanglement applies not only through space, but through time as well. Entanglement, famously referred to as “spooky” by Einstein, is the quantum property that involves two or more particles so closely linked that any changes to one also occur in the other(s).

The Queensland physicists believe that thinking about the universe as consisting of one dimension of space and one dimension of time can begin to demonstrate how entangled atoms can span time as well as space. Looking at the above graph, the x-axis represents spatial dimension and the y-axis represents time. If two particles are present on the x-axis, their representations of the “past” and “future” on the y-axis will overlap – meaning that the particles could have interacted in the past and could interact again in the future, but only in the areas where the “past” and “future” representations overlap. In essence, the physicists are saying what anyone familiar with quantum theory already knows: entanglement transcends both physical space and the human measures of time.

However, the Queensland research indicates that it is possible to travel from the present to the future without traveling through the time in between the two – possible for a particle, anyway. According ot the researchers, the future detection of the qubit must line up with its creation in the past. The example given by the researchers is “if the past detector was active at a quarter to 12:00, then the future detector must wait to become active at precisely a quarter past 12:00 in order to achieve entanglement.” Thanks to this peculiarity, the researchers are calling their research “teleportation in time.” Because spatial teleportation is almost a routine practice in labs today, it’s only a matter of time before scientists start tinkering with sending particles into the future.

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