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Wave-particle Duality

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Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time. Now they’re just messing with us.

Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

Physicists have long known that quantum mechanics allows for a subtle connection between quantum particles called entanglement, in which measuring one particle can instantly set the otherwise uncertain condition, or “state,” of another particle—even if it’s light years away. Now, experimenters in Israel have shown that they can entangle two photons that don’t even exist at the same time. “It’s really cool,” says Jeremy O’Brien, an experimenter at the University of Bristol in the United Kingdom, who was not involved in the work. Such time-separated entanglement is predicted by standard quantum theory, O’Brien says, “but it’s certainly not widely appreciated, and I don’t know if it’s been clearly articulated before.”

Tricking the uncertainty principle. ( —Caltech researchers have found a way to make measurements that go beyond the limits imposed by quantum physics.

Tricking the uncertainty principle

Today, we are capable of measuring the position of an object with unprecedented accuracy, but quantum physics and the Heisenberg uncertainty principle place fundamental limits on our ability to measure. Noise that arises as a result of the quantum nature of the fields used to make those measurements imposes what is called the "standard quantum limit. " This same limit influences both the ultrasensitive measurements in nanoscale devices and the kilometer-scale gravitational wave detector at LIGO. Because of this troublesome background noise, we can never know an object's exact location, but a recent study provides a solution for rerouting some of that noise away from the measurement. Largest Molecules Yet Behave Like Waves in Quantum Double-Slit Experiment. One of the most famous experiments in quantum physics, which first showed how particles can bizarrely behave like waves, has now been carried out on the largest molecules ever.

Largest Molecules Yet Behave Like Waves in Quantum Double-Slit Experiment

Researchers have sent molecules containing either 58 or 114 atoms through the so-called "double-slit experiment," showing that they cause an interference pattern that can only be explained if the particles act like waves of water, rather than tiny marbles. Researchers said it wasn't a foregone conclusion that such large particles would act this way. "In a way it's a little bit surprising, because these are highly complex and also flexible molecules; they change their shape while they're flying through the apparatus," said Markus Arndt of the University of Vienna in Austria, a co-leader of the project. "If you talk to the community, maybe 50 percent would say this is normal because it's quantum physics, and the other 50 percent would really scratch their heads because it's quantum physics. " Beautiful experiment. This Will Mindfuck You: The Double-Slit Experiment. The video below shows scientific proof that there is something NOT quite logical or scientific about this universe.

This Will Mindfuck You: The Double-Slit Experiment

Does the Universe Exist if We're Not Looking? The world seems to be putting itself together piece by piece on this damp gray morning along the coast of Maine.

Does the Universe Exist if We're Not Looking?

First the spruce and white pine trees that cover High Island materialize from the fog, then the rocky headland, and finally the sea, as if the mere act of watching has drawn them all into existence. And that may indeed be the case. While this misty genesis unfolds, the island's most eminent residentdiscusses notions that still perplex him after seven decades in physics, including his gut feeling that the very universe may be constantly emerging from a haze of possibility, that we inhabit a cosmos made real in part by our own observations. John Wheeler, scientist and dreamer, colleague of Albert Einstein and Niels Bohr, mentor to many of today's leading physicists, and the man who chose the name "black hole" to describe the unimaginably dense, light-trapping objects now thought to be common throughout the universe, turned 90 last July.

Quantum physics just got less complicated. Here's a nice surprise: quantum physics is less complicated than we thought.

Quantum physics just got less complicated

An international team of researchers has proved that two peculiar features of the quantum world previously considered distinct are different manifestations of the same thing. The result is published 19 December in Nature Communications. Patrick Coles, Jedrzej Kaniewski, and Stephanie Wehner made the breakthrough while at the Centre for Quantum Technologies at the National University of Singapore. They found that 'wave-particle duality' is simply the quantum 'uncertainty principle' in disguise, reducing two mysteries to one. "The connection between uncertainty and wave-particle duality comes out very naturally when you consider them as questions about what information you can gain about a system.

The first ever photograph of light as both a particle and wave. (—Light behaves both as a particle and as a wave.

The first ever photograph of light as both a particle and wave

Since the days of Einstein, scientists have been trying to directly observe both of these aspects of light at the same time. Now, scientists at EPFL have succeeded in capturing the first-ever snapshot of this dual behavior. Quantum mechanics tells us that light can behave simultaneously as a particle or a wave. However, there has never been an experiment able to capture both natures of light at the same time; the closest we have come is seeing either wave or particle, but always at different times.

Taking a radically different experimental approach, EPFL scientists have now been able to take the first ever snapshot of light behaving both as a wave and as a particle. When UV light hits a metal surface, it causes an emission of electrons. A research team led by Fabrizio Carbone at EPFL has now carried out an experiment with a clever twist: using electrons to image light. Share Video undefined.