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Quantum Experiment Confirms Causality Is Fuzzy (physicsworld.com)
"An experiment has confirmed that quantum mechanics allows events to occur with no definite causal order," reports an article shared by long-time Slashdot readers UpnAtom and jd. Researchers at the University of Queensland in Australia believe this could link Einstein's general theory of relativity to quantum mechanics, according to Physics World:
In classical physics -- and everyday life -- there is a strict causal relationship between consecutive events. If a second event (B) happens after a first event (A), for example, then B cannot affect the outcome of A. This relationship, however, breaks down in quantum mechanics because the temporal spread of a particles's wave function can be greater than the separation in time between A and B. This means that the causal order of A and B cannot be always be distinguished by a quantum particle such as a photon.
In their experiment, Romero, Costa and colleagues created a "quantum switch", in which photons can take two paths. One path involves being subjected to operation A before operation B, while in the other path B occurs before A. The order in which the operations are performed is determined by the initial polarization of the photon as it enters the switch.... The team did the experiment using several different types of operation for A and B and in all cases they found that the measured polarization of the output photons was consistent with their being no definite causal order between when A and B was applied. Indeed, the measurements backed indefinite causal order to a whopping statistical significance of 18 -- well beyond the 5 threshold that is considered a discovery in physics.
Science Magazine applauds the experiments for "obliterating our common sense notion of before and after and, potentially, muddying the concept of causality.
In their experiment, Romero, Costa and colleagues created a "quantum switch", in which photons can take two paths. One path involves being subjected to operation A before operation B, while in the other path B occurs before A. The order in which the operations are performed is determined by the initial polarization of the photon as it enters the switch.... The team did the experiment using several different types of operation for A and B and in all cases they found that the measured polarization of the output photons was consistent with their being no definite causal order between when A and B was applied. Indeed, the measurements backed indefinite causal order to a whopping statistical significance of 18 -- well beyond the 5 threshold that is considered a discovery in physics.
Science Magazine applauds the experiments for "obliterating our common sense notion of before and after and, potentially, muddying the concept of causality.
Your hosts file shit doesn't protect against speculative execution vulnerabilities no matter how much you lie and claim it does. Shut the fuck up and stop spamming.
Science Magazine applauds the experiments for "obliterating our common sense notion of before and after and, potentially, muddying the concept of causality.
If anything I'd say a big "Duck you" was in order for guaranteeing that no non-physicist will ever understand quantum physics ever again. ... But on the other hand, it might get me out of the dog house for getting drunk and breaking the living room table...
Non-physicists may not understand quantum mechanics, but they're in good company.
I think I can safely say that nobody understands quantum mechanics. -- Richard Feynman
If it weren't for deadlines, nothing would be late.
I've been thinking about time lately. Why do we assume we only move forward in time? We move forward and backward in all the other dimensions, why assume we aren't oscillating back and forth in time? What difference would that make if we were? How would we know?
Consider the double slit experiment. Everyone reading this by now knows that if you send a single photon through a double slit it refracts as a wave until it hits the screen, then the "waveform" collapses and becomes a single point of light. Now imagine that quantum particle moving forward a ways, then moving backward a ways, vibrating back-and-forth in time. Each time it vibrates backward it interacts with itself as it's waveform briefly overlap it past self at the edges. This would cause it to refract against itself through the double slit. Then, once it's finally made it to the screen it appears to the observer as a single photon.