Why Einstein's Spacetime Is Doomed as Fundamental Notion

Nima Arkani-Hamed (5:24): "It's been clear to many people for a long time that the idea of spacetime isn't fundamental, that spacetime is doomed as a fundamental notion and has to be replaced by someting else."
https://www.youtube.com/watch?v=hJPbmfKiFbw

Spacetime is a consequence of Einstein's constant-speed-of-light postulate so if it is doomed and has to be replaced, logic says that the postulate is false:

"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/20...rs-of-gravity/

Pentcho Valev

"Rethinking Einstein: The end of space-time. It was a speech that changed the way we think of space and time. The year was 1908, and the German mathematician Hermann Minkowski had been trying to make sense of Albert Einstein's hot new idea - what we now know as special relativity - describing how things shrink as they move faster and time becomes distorted. "Henceforth space by itself and time by itself are doomed to fade into the mere shadows," Minkowski proclaimed, "and only a union of the two will preserve an independent reality." And so space-time - the malleable fabric whose geometry can be changed by the gravity of stars, planets and matter - was born. It is a concept that has served us well, but if physicist Petr Horava is right, it may be no more than a mirage. Horava, who is at the University of California, Berkeley, wants to rip this fabric apart and set time and space free from one another in order to come up with a unified theory that reconciles the disparate worlds of quantum mechanics and gravity - one the most pressing challenges to modern physics."
https://www.newscientist.com/article...of-space-time/

To "rip this fabric apart and set time and space free from one another" means to declare two things:

1. The premise from which spacetime has been derived, Einstein's constant-speed-of-light postulate, is false.

2. Gravitational waves (ripples in spacetime) don't exist - LIGO folks are fraudsters.

Petr Horava is not so brave. Perhaps he doesn't want to rip spacetime apart anymore and sings dithyrambs to LIGO's victorious godfathers. Like his brother string theorist Steve Giddings who once wanted to retire spacetime but now believes that the ripples in spacetime are worth living for:

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://www.edge.org/response-detail/25477

"In celebration of Einstein's birthday, physicists reflect on the German-born scientist's work and its impact on the field and on everyday life. "We have good reason to believe general relativity is not a complete theory and, in particular, that it's going to break down in the context of describing black holes," said UCSB physics professor Steve Giddings. "That's very much an important problem in physics today. "The direct observation of gravitational waves from colliding black holes really constrains the possible departures from general relativity that we know are there and limits where modifications can be made," he continued. "But the discovery is still spectacular and its announcement was one of those moments in science that you live for." http://www.news.ucsb.edu/2016/016562...ein-revolution

Pentcho Valev

Einstein's spacetime is not just the false alternative to Newton's absolute time. It is a paralyzing idiocy incapable of any prediction about clocks. Popular "predictions" - "Moving clocks run slow", "Traveling twin returns younger" - are actually non sequitur. This was clear to Einstein from the very beginning:

Albert Einstein, On the Electrodynamics of Moving Bodies, 1905: "From this there ensues the following peculiar consequence. If at the points A and B of K there are stationary clocks which, viewed in the stationary system, are synchronous; and if the clock at A is moved with the velocity v along the line AB to B, then on its arrival at B the two clocks no longer synchronize, but the clock moved from A to B lags behind the other which has remained at B by tv^2/2c^2 (up to magnitudes of fourth and higher order), t being the time occupied in the journey from A to B." http://www.fourmilab.ch/etexts/einstein/specrel/www/

The conclusion

"the clock moved from A to B lags behind the other which has remained at B"

does not follow from Einstein's 1905 postulates - the argument is INVALID. This means that the conclusion is unacceptable no matter whether the postulates (the principle of relativity and the constancy of the speed of light) are true or false. The wisdom "Moving clocks run slow" is just a generalized formulation of Einstein's 1905 non sequitur.

The following two conclusions, in contrast, VALIDLY follow from the postulates (they will be true if the postulates are true):

Conclusion 1: The clock moved from A to B lags behind the other which has remained at B, as judged from the stationary system.

Conclusion 2: The clock which has remained at B lags behind the clock moved from A to B, as judged from the moving system.

Conclusions 1 and 2 (symmetrical time dilation) in their combination give no prediction for the readings of the two clocks as they meet at B. This remains the central feature of Einstein's spacetime - without recourse to invalid arguments, it is unable to predict anything about clocks.

Unlike conclusions 1 and 2, the INVALIDLY deduced conclusion does provide a prediction - the moving clock is SLOW, the stationary one is FAST (asymmetrical time dilation). The famous "travel into the future" is a direct implication of the INVALIDLY deduced conclusion - the slowness of the moving clock means that its (moving) owner can remain virtually unchanged while sixty million years are passing for the stationary system:

Thibault Damour: "The paradigm of the special relativistic upheaval of the usual concept of time is the twin paradox. Let us emphasize that this striking example of time dilation proves that time travel (towards the future) is possible. As a gedanken experiment (if we neglect practicalities such as the technology needed for reaching velocities comparable to the velocity of light, the cost of the fuel and the capacity of the traveller to sustain high accelerations), it shows that a sentient being can jump, "within a minute" (of his experienced time) arbitrarily far in the future, say sixty million years ahead, and see, and be part of, what (will) happen then on Earth. This is a clear way of realizing that the future "already exists" (as we can experience it "in a minute")." http://www.bourbaphy.fr/damourtemps.pdf

Pentcho Valev