"The future ain't what it used to be."

Scientists simulating backward time travel with 25% success rate


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Cambridge University scientists have recently succeeded in simulating a form of backward time travel. By manipulating the properties of quantum entangled particles, the team was able to change an event after it has occurred. However, the success rate for this change stands at 25%.

Lead author David Arvidsson-Shukur presented an interesting analogy to help us understand this complex concept. Imagine needing to send a gift on Day 1, but only knowing what gift to send on Day 2. By using their quantum entanglement manipulation, you can retroactively change your previous actions so that the gift sent on Day 1 is exactly what was wished for on Day 2.

According to the study published in the Physical Review Letters, the scientists used a simulation that entangled two particles. By manipulating one particle after gaining new information, they were able to retroactively affect the first particle and, therefore, change the past. However, this change occurred only 25% of the time.

This discovery raises both ethical and scientific questions. While fascinating, the ability to alter past events even theoretically questions the sanctity of Einstein's theories of relativity and other foundations of physics. It also makes one wonder about the ethics of changing past events.

According to the research team, there is a 75% chance that the simulation will fail to alter the past. This actually serves as a reassurance, as it doesn't completely overthrow existing physical theories. The researchers also emphasized that these are just simulations, not an actual "time machine."

Source article:
This is a very interesting find! :)

However, I must note that this report is likely just scratching the surface, in other words, far less than 1% of time travel/altering the past information available throughout this vast universe, and also counting alternate dimensions, etc. Hell, I bet there are scientists out there that believe that this article merely scratches the surface as well, though they won't admit it in public as that would give away too many secrets.
Keep in mind the last sentence of the abstract for this paper:

"Our Gedankenexperiment demonstrates that entanglement can generate operational advantages forbidden in classical chronology-respecting theories." (bold italic added - Darby)

They didn't actually build a physical simulator or any other physical system. It's a thought experiment. The next step is for the experimentalists to run it through its paces by constructing a real, physical system to manipulate.

Also keep in mind the last sentence of the Conclusions section of the paper:

"Our Gedankenexperiment thus draws a metrological advantage from effective retrocausation founded in entangled states. While PCTC simulations do not allow you to go back and alter your past, they do allow you to create a better tomorrow by fixing yesterday’s problems today." (bold italic add - Darby)

As the paper discusses at length, in the end chronology isn't violated. You glean information about yesterday so you can use it today - which is how we normally perceive time and events. The chronological order of events of Cause ---> Effect is not violated.
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