A team of physicists claims to have simultaneously shifted light from one side of time to the other, using a quantum technique to transport a photon (light particle) forward and backward in time.
Two separate research groups have demonstrated the quantum experiment in which a particle of light simultaneously travels backwards and forwards across time. Can a photon exist in two time states simultaneously?
How did they accomplish this?
Using a unique optical crystal and the convergence of quantum superposition and the symmetry of charge, parity, and time reversal (CPT), which explain the physical properties of atoms and subatomic particles, the scientists participating in both experiments were able to accomplish this feat.
Due to this effect, splitting a photon through a crystal results in an unexpected rule or behavior. Schrodinger’s famous hypothetical cat, which is regarded both living and dead because its life is in the hands of a random subatomic event that has no place until witnessed, is the clearest example of quantum superposition we are aware of. In contrast, the second law, symmetry of charge, parity, and time reversal, stipulates that any system containing particles will adhere to the same physical rules regardless of the charges, spatial coordinates, and temporal motions of the particles. This enables a particle that overlaps to go both forward and backward in time.
By analyzing the polarization of the photons during the experiment and recombining the overlapping photons as they passed through another crystal, scientists discovered a quantum interference pattern: a pattern that could only emerge if the same photon travelled in both directions. Indeed, a photon appeared to travel both forward and backward down the arrow of time.
Placing a particle of light in an overlay to go both forward and backward in time could be useful for computation, if proven, as the research are pending peer review and are available on the arXiv preprint server. quantum (and not so much to give us time travel, which is undoubtedly what many readers are thinking) (and not so much to allow us time travel, which is surely what many readers are thinking). It would not have an immediate practical application, but it could have consequences for quantum computers and potentially contribute to the development of a quantum gravity theory. We will soon determine whether this unusual physics experiment opens up new avenues in quantum physics.
Time travel would only be possible in parallel time lines.
Reference: Experimental superposition of time directions
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