HomeSci-Tech Physicists used 'Quantum time flip' to make light flow forward and backward in time at the same time.
Physicists have made light move in time for the first time. Scientists could use the new technique to improve quantum computing. Two teams of physicists have achieved a 'quantum time flip', in which a photon exists in both forward and backward time states, by splitting a packet of light using a special optical crystal. The convergence of two strange principles of quantum mechanics resulted in the effect.
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The first principle of quantum superposition is that minuscule particles can exist in many different states until they are observed. Any system containing particles will obey the same physical laws even if the particles' charges, spatial coordinates and movements are flipped as if through a mirror, according to charge, parity and time-reversal symmetry.
The physicists produced a photon that traveled along and against the arrow of time. The results of their experiments were published. 31 and Nov. The findings have not yet been peer-reviewed. Teodor Strmberg, a physicist at the University of Vienna, was the first author on one of the papers. Many of the fundamental laws of physics, which by and large are time symmetric, do not have a preferred time direction. The second law of thermodynamics states that the system's entropy must increase.
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One of the few quantities in physics that sets time in a specific direction is thearrow of time. It's easier to mix ingredients than to separate them because of the tendency for disorder in the universe. Our sense of time is tied to this growing disorder. There is a famous scene in Kurt Vonnegut's novel "Slaughterhouse-Five" in which bullets are sucked from wounded men, fires are shrunk, and bombs are stacked in neat rows. As a statistical concept, it doesn't apply to single particles.
Every particle interaction scientists have observed so far, including the up to 1 billion interactions per second that take place inside the world's largest atom smasher, CPT symmetry is upheld. The mirrored system of antiparticles moving backward in time is different from the seeming particles moving forward in time.
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Antimatter was created with matter and doesn't actually move backwards in time, it just behaves as if it is following an opposite arrow of time to normal matter. Superposition is one of the factors at play in the new experiments. The most famous demonstration of quantum superposition is Schrdinger's cat, a thought experiment in which a cat is placed inside a sealed box with poison in it.
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It is not possible to know what happened to the cat until the box is opened and the outcome observed. The ability to exist in both forward and backward time states at the same time is difficult to observe. Both teams devised similar experiments to split a photon along a path through a crystal. The superposed photon moved on one path through the crystal as normal, but another path was configured to change the photon's direction in order to travel back in time.
The team measured the photon polarization after sending the superposed photons through another crystal. If the photon had been split and the light and dark stripes were moving in the same direction, there would be a quantum interference pattern. Strmberg said that the superposition of processes is akin to an object spinning clockwise and counter-clockwise at the same time.
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The researchers created their time-flipped photon out of intellectual curiosity, but follow-up experiments showed that time flips can be coupled with logic gates to enable simultaneous computation in either direction, thus opening the way for quantum processors with greatly enhanced processing power. There are possibilities from the work.
A future theory of quantum gravity, which would unite general relativity and quantum mechanics, should include particles of mixed time orientations like the one in this experiment, and could enable the researchers to peer into some of the universe's most mysterious phenomena. "Our experiment is a simulation of exotic scenarios where a photon might evolve forward and backward in time," said Giulio Chiribella, a physicist at the University of Oxford who was the lead author of the other paper. We do some experiments that are similar to exotic physics, such as the physics of black holes or time travel."
Sources:
1- Experimental demonstration of input-output indefiniteness in a single quantum device
https://doi.org/10.48550/arXiv.2210.17046
2- Experimental superposition of time directions
https://doi.org/10.48550/arXiv.2211.01283
3- The God Effect: Quantum Entanglement, Science’s Strangest Phenomenon