Kip Thorne: “We simply don’t know whether backward time travel is possible. The answer, as best I can tell, is controlled by laws of quantum gravity, laws that come from combining general relativity with quantum physics. Only when we understand those laws of quantum gravity far better than we do today will we be able, theoretically, to answer the question of whether you can go backward in time. That’s probably a few decades away.”
http://thepolitic.org/an-interview-with-kip-thorne-theoretical-physicist-and-2017-nobel-prize-recipient/
That is, Einsteinians will know whether backward time travel is possible when they manage to reconcile Einstein’s idiotic spacetime, the consequence of his false constant-speed-of-light postulate, and Newton’s absolute time, in the way in which theoreticians in Big Brother’s world reconcile 2+2=5 and 2+2=4:
"Special relativity is based on the observation that the speed of light is always the same, independently of who measures it, or how fast the source of the light is moving with respect to the observer. Einstein demonstrated that as an immediate consequence, space and time can no longer be independent, but should rather be considered a new joint entity called "spacetime."
http://community.bowdoin.edu/news/2015/04/professor-baumgarte-describes-100-years-of-gravity/
Nima Arkani-Hamed (06:09): "Almost all of us believe that space-time doesn't really exist, space-time is doomed and has to be replaced by some more primitive building blocks."
https://www.youtube.com/watch?v=U47kyV4TMnE
Nobel Laureate David Gross observed, "Everyone in string theory is convinced...that spacetime is doomed. But we don't know what it's replaced by."
https://www.edge.org/response-detail/26563
What scientific idea is ready for retirement? Steve Giddings: "Spacetime. Physics has always been regarded as playing out on an underlying stage of space and time. Special relativity joined these into spacetime... [...] The apparent need to retire classical spacetime as a fundamental concept is profound..."
https://edge.org/response-detail/25477
"And by making the clock's tick relative - what happens simultaneously for one observer might seem sequential to another - Einstein's theory of special relativity not only destroyed any notion of absolute time but made time equivalent to a dimension in space: the future is already out there waiting for us; we just can't see it until we get there. This view is a logical and metaphysical dead end, says Smolin."
http://www.guardian.co.uk/books/2013/jun/10/time-reborn-farewell-reality-review
"Was Einstein wrong? At least in his understanding of time, Smolin argues, the great theorist of relativity was dead wrong. What is worse, by firmly enshrining his error in scientific orthodoxy, Einstein trapped his successors in insoluble dilemmas..."
https://www.amazon.com/Time-Reborn-Crisis-Physics-Universe-ebook/dp/B00AEGQPFE
"Splitting Time from Space - New Quantum Theory Topples Einstein's Spacetime. Buzz about a quantum gravity theory that sends space and time back to their Newtonian roots. Was Newton right and Einstein wrong? It seems that unzipping the fabric of spacetime and harking back to 19th-century notions of time could lead to a theory of quantum gravity. [...] But now Petr Hořava, a physicist at the University of California, Berkeley, thinks he understands the problem. It's all, he says, a matter of time. More specifically, the problem is the way that time is tied up with space in Einstein's theory of gravity: general relativity. Einstein famously overturned the Newtonian notion that time is absolute - steadily ticking away in the background. Instead he argued that time is another dimension, woven together with space to form a malleable fabric that is distorted by matter. The snag is that in quantum mechanics, time retains its Newtonian aloofness, providing the stage against which matter dances but never being affected by its presence. These two conceptions of time don't gel."
https://www.scientificamerican.com/article/splitting-time-from-space/
"The effort to unify quantum mechanics and general relativity means reconciling totally different notions of time. In quantum mechanics, time is universal and absolute; its steady ticks dictate the evolving entanglements between particles. But in general relativity (Albert Einstein's theory of gravity), time is relative and dynamical, a dimension that's inextricably interwoven with directions X, Y and Z into a four-dimensional "space-time" fabric."
https://www.quantamagazine.org/20161201-quantum-gravitys-time-problem/
Perimeter Institute: "Quantum mechanics has one thing, time, which is absolute. But general relativity tells us that space and time are both dynamical so there is a big contradiction there. So the question is, can quantum gravity be formulated in a context where quantum mechanics still has absolute time?"
https://www.perimeterinstitute.ca/research/conferences/convergence/roundtable-discussion-questions/what-are-lessons-quantum
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