According to a new study, photons, the light particles, can travel over vast distances without losing their quantum nature. It means scientists can use photons to look for quantum messages to search for extraterrestrial signals.
Currently, scientists are developing earth-based quantum communication systems using quantum particles to send information. This technology is more secure than standard or classical communication. It is hoped the technology could provide an ‘unhackable,’ high-speed internet in the future.
Theoretical physicist Arjun Berbera suggested that aliens may have also adopted quantum communication if there existed.
Decoherence is a significant obstacle to quantum communication, which occurs when a quantum particle loses some or all of its unique characteristics as it interacts with its surroundings.
Berbera said, “Quantum states you generally think of as very delicate, and if there’s any external interaction, you destroy that state.”
Since the matter in space has a far lower average density than it does on Earth, particles may travel further before succumbing to decoherence. Therefore, Berbera and theoretical physicist Jaime Calderón Figueroa of the University of Edinburgh determined the maximum distance that light, in particular X-rays, could travel through interstellar space without damage.
Their calculations proved that the quantum particles could be beamed over large interstellar distances. It could survive traveling hundreds of thousands of light-years at least – a greater stretch of distance than the entire Milky Way galaxy.
Using astronomical data and mathematical models, they described the movement of X-Rays between roughly a hundred nearby exoplanets and Earth. It was determined that the quanta would most likely not encounter any significant impediments at this distance.
Scientists noted, “It is plausible that quantum communication mediated by photons could be established across interstellar distances, particularly for photons in the X-ray region below the electron mass.”
“The level of information that can be securely transferred using quantum communication at high speeds could make it a viable method of communication to other life forms.”
According to the researchers, there are currently no objects that naturally transmit quantum messages that could be misinterpreted for signals from extraterrestrial life.
However, it would require a powerful quantum computer on Earth to decode any.
Scientists noted, “It is currently only speculation, but the research does give experts another sign of life to look out for.”
Journal Reference:
- Arjun Berera and Jaime Calderón-Figueroa. Viability of quantum communication across interstellar distances. Phys. Rev. D 105, 123033 – Published 28 June 2022. DOI: 10.1103/PhysRevD.105.123033