Physicists have demonstrated that simulating hypothetical time travel models can potentially help resolve experimental challenges that seem unsolvable within conventional physics. By manipulating quantum entanglement, researchers at the University of Cambridge have explored the concept of retroactively altering past actions, potentially offering advantages to gamblers, investors, and quantum experimentalists.
While the idea of particles traveling backward in time remains controversial in the physics community, these scientists connected their theory to quantum metrology, which involves using quantum principles for highly sensitive measurements. Their findings are published in Physical Review Letters.
Lead author David Arvidsson-Shukur explained the concept with a gift-giving analogy, highlighting the challenge of sending a gift before knowing the recipient’s preferences. They proposed that quantum entanglement manipulation could enable individuals to change their previous actions retroactively to achieve desired outcomes.
Quantum entanglement is the unique property where particles, when close enough to interact, remain interconnected even when separated, forming the foundation of quantum computing.
Co-author Nicole Yunger Halpern outlined the process: An experimentalist entangles two particles, sends one for an experiment, gains new information, and uses the second particle to alter the first particle’s past state, affecting the experiment’s outcome.
However, this simulation is not foolproof, with a 75% chance of failure. Researchers suggested mitigating this by sending numerous entangled photons, then using a filter to ensure only the correct information is retained.
Aidan McConnell, another co-author, offered an analogy, comparing the process to sending gifts inexpensively and selecting the right ones after learning the recipient’s preferences on the second day. In this scenario, one out of every four gifts would be correct, guided by the filter’s selection.
Despite the potential for failure, the need for a filter is seen as a reassuring aspect, ensuring consistency with established physics theories. The researchers emphasized that this is not a proposal for a time travel machine but an exploration of the fundamental principles of quantum mechanics, offering the possibility of addressing yesterday’s problems to create a better tomorrow.
Source: University of Cambridge