A team of physicists at the Universities of Bristol, Vienna, the Balearic Islands and the Institute for Quantum Optics and Quantum Information (IQOQI-Vienna) has shown how quantum systems can simultaneously evolve along two opposite time arrows—both forward and backward in time.
The study, published in the latest issue of Communications Physics, necessitates a rethink of how the flow of time is understood and represented in contexts where quantum laws play a crucial role.
Dr. Gonzalo Manzano, co-author from the University of the Balearic Islands, said: "In our work, we quantified the entropy produced by a system evolving in quantum superposition of processes with opposite time arrows. We found this most often results in projecting the system onto a well-defined time's direction, corresponding to the most likely process of the two. And yet, when small amounts of entropy are involved (for instance, when there is so little toothpaste spilled that one could see it being reabsorbed into the tube), then one can physically observe the consequences of the system having evolved along the forward and backward temporal directions at the same time."
Quantum superposition of thermodynamic evolutions with opposing time's arrows, Communications Physics (2021). DOI: 10.1038/s42005-021-00759-1
A preprint of their paper is available.
(Score: 1, Funny) by Anonymous Coward on Sunday November 28 2021, @07:03AM (1 child)
Time travel makes for science fiction but the idea one can invent a bigger on the inside phone box to travel back to previous events that have already happened is, a priori, nonsense.
(Score: 2, Funny) by Anonymous Coward on Sunday November 28 2021, @09:29AM
That's just your timey wimey opinion.
(Score: 4, Informative) by Anonymous Coward on Sunday November 28 2021, @07:10AM
"Quantum superposition of thermodynamic evolutions with opposing time’s arrows"
https://www.nature.com/articles/s42005-021-00759-1 [nature.com]
(Score: 3, Insightful) by Anonymous Coward on Sunday November 28 2021, @10:24AM (2 children)
Than the usual treatment of entropy? Which was statistical to begin with?
I always thought the arrow of time was a consequence of the bulk flow going one direction because there's simply more available ways to disorder the system? And there never was anything preventing "backward" motion on the scale of individual events?
(Score: 2) by legont on Monday November 29 2021, @04:54AM (1 child)
Yep. I for one really want my dishes to clean themselves back.
"Wealth is the relentless enemy of understanding" - John Kenneth Galbraith.
(Score: 1, Insightful) by Anonymous Coward on Monday November 29 2021, @01:52PM
(Score: 3, Funny) by Barenflimski on Sunday November 28 2021, @10:49AM (1 child)
Ahh, good ole quantum physics. You know a seasoned physicist when their summaries read like horoscopes.
Statistically, this sounds plausible for a quantum system.
For the conscious being, time will only ever flow in one direction, which is a circle.
(Score: -1, Spam) by Anonymous Coward on Sunday November 28 2021, @03:56PM
It reads more like a mystical pseudo science [landoverbaptist.net]
(Score: 1, Insightful) by Anonymous Coward on Sunday November 28 2021, @12:51PM (5 children)
i am more interested in outcomes, like did the toothpaste really spill and, over time, clog the siphone.
if it spills, makes a round trip thru the universe but ends up back in the tube, the observer doesn't have to waste a afternoon de-clogging the siphone, eh?
also, "morphological fields".
(Score: 1, Funny) by Anonymous Coward on Sunday November 28 2021, @04:00PM (3 children)
Toothpaste what now? That line came straight out of left field.
And the baboons were rarely troubled by the glockenspiel. The end.
(Score: 0) by Anonymous Coward on Sunday November 28 2021, @04:36PM (2 children)
Indeed, this sounds like a classic temporal pincer maneuver. Toothpaste has nothing to do with it.
(Score: 1, Informative) by Anonymous Coward on Sunday November 28 2021, @04:45PM (1 child)
Au contraire. Dr. Gonzalo Manzano, co-author from the University of the Balearic Islands, clearly mentions toothpaste.
(Score: 2) by edIII on Monday November 29 2021, @08:30PM
That statement sounds like it came straight out of The Hitchhiker's Guide To The Galaxy.
Technically, lunchtime is at any moment. It's just a wave function.
(Score: 1, Funny) by Anonymous Coward on Sunday November 28 2021, @11:06PM
Morphological fields are how the Heisenberg compensators work.