The Red Herring Called Quantum Gravity

Sabine Hossenfelder: "But we know that general relativity is incomplete. It works well when the quantum effects of space-time are small, which is almost always the case. But when the quantum effects of space-time become large we need a better theory: a theory of "quantum gravity". Since we don't yet know the theory of quantum gravity, we don't really know what space, and time, are. We have several candidate theories for quantum gravity, but none of them is generally accepted. Nevertheless, based on the existing approaches, we can speculate what might happen with space and time in a theory of quantum gravity. Here, I have collected the ten most mind-boggling speculations for you." https://www.forbes.com/sites/startsw...y-could-solve/

Something might happen with "space and time" but nothing can happen with SPACETIME. The reason is that spacetime is a DEDUCTION and therefore it remains unalterable as long as the postulates remain unchanged:

"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/

So Sabine Hossenfelder's "ten most mind-boggling speculations" are just silly red herrings - she doesn't know what she is talking about.

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Nowadays almost all theoreticians, just like Sabine Hossenfelder, find the current version of Einstein's spacetime unacceptable - they promise to modify and even replace it. However, as powerful thinkers in Einstein's schizophrenic world, theoreticians continue to worship the underlying premise, Einstein's constant-speed-of-light postulate, knowing (or not knowing) that the combination "unacceptable consequence, true underlying premise" is forbidden by logic:

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

"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." https://www.scientificamerican.com/a...me-from-space/

New Scientist: "Saving time: Physics killed it. Do we need it back? [...] Einstein landed the fatal blow at the turn of the 20th century." https://www.newscientist.com/article...-need-it-back/

Joao Magueijo, Faster Than the Speed of Light, p. 250: "Lee [Smolin] and I discussed these paradoxes at great length for many months, starting in January 2001. We would meet in cafés in South Kensington or Holland Park to mull over the problem. THE ROOT OF ALL THE EVIL WAS CLEARLY SPECIAL RELATIVITY. All these paradoxes resulted from well known effects such as length contraction, time dilation, or E=mc^2, all basic predictions of special relativity. And all denied the possibility of establishing a well-defined border, common to all observers, capable of containing new quantum gravitational effects." http://www.amazon.com/Faster-Than-Sp.../dp/0738205257

"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...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-C.../dp/B00AEGQPFE

"[George] Ellis is up against one of the most successful theories in physics: special relativity. It revealed that there's no such thing as objective simultaneity. [...] Rescuing an objective "now" is a daunting task." https://www.newscientist.com/article...wards-in-time/

Brian Greene: "Special relativity in some sense is surely wrong." https://www.youtube.com/watch?v=1uVZEg9gxM8

"...says John Norton, a philosopher based at the University of Pittsburgh, Pennsylvania. Norton is hesitant to express it, but his instinct - and the consensus in physics - seems to be that space and time exist on their own. The trouble with this idea, though, is that it doesn't sit well with relativity, which describes space-time as a malleable fabric whose geometry can be changed by the gravity of stars, planets and matter." https://www.newscientist.com/article...-universe-tick

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/re...essons-quantum

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Nima Arkani-Hamed has been making fun of the gullible world for many years:

The Doom of Spacetime: Why it Must Dissolve into More Fundamental Structures. 2,384th Meeting of PSW Science. Lecturer: Nima Arkani-Hamed, Professor, The Institute for Advanced Study, Princeton, and A. D. White Professor-at-Large, Cornell University https://www.youtube.com/watch?v=smRNUqMPObQ

Spacetime is a DEDUCTION so the only things into which it can dissolve are the premises from which it has been deduced - Einstein's 1905 postulates. If the current version of spacetime is unacceptable, a postulate is false - logic does not allow the combination "true premises, unacceptable conclusion".

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"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/20161...-time-problem/

The two notions of time are obviously irreconcilable. Then why have theoreticians been reconciling them for more than half a century? "Schizophrenia" is only part of the answer. The other part is: Since Einstein's relative time is absurd, the eternal reconciliation is the only way to save Einstein's relativity:

"On one hand, time in quantum mechanics is a Newtonian time, i.e., an absolute time. In fact, the two main methods of quantization, namely, canonical quantization method due to Dirac and Feynman's path integral method are based on classical constraints which become operators annihilating the physical states, and on the sum over all possible classical trajectories, respectively. Therefore, both quantization methods rely on the Newton global and absolute time. [...] The transition to (special) relativistic quantum field theories can be realized by replacing the unique absolute Newtonian time by a set of timelike parameters associated to the naturally distinguished family of relativistic inertial frames." http://arxiv.org/pdf/gr-qc/0610057.pdf

New Scientist: "In quantum theory, a "master clock" ticks away somewhere in the universe, measuring out all processes. But in Einstein's relativity, time is distorted by motion and gravity, so clocks don't necessarily agree on how it is passing - meaning any master clock must, somewhat implausibly, be outside the universe." https://www.newscientist.com/article...-go-both-ways/

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?"x https://www.perimeterinstitute.ca/re...essons-quantum

Science: "In Einstein's general theory of relativity, time depends locally on gravity; in standard quantum theory, time is global – all clocks "tick" uniformly." http://science.sciencemag.org/conten...cience.aac6498

Frank Wilczek: "Einstein's special theory of relativity calls for radical renovation of common-sense ideas about time. Different observers, moving at constant velocity relative to one another, require different notions of time, since their clocks run differently. Yet each such observer can use his "time" to describe what he sees, and every description will give valid results, using the same laws of physics. In short: According to special relativity, there are many quite different but equally valid ways of assigning times to events. Einstein himself understood the importance of breaking free from the idea that there is an objective, universal "now." Yet, paradoxically, today's standard formulation of quantum mechanics makes heavy use of that discredited "now." http://www.pbs.org/wgbh/nova/blogs/p...uantum-theory/

"In quantum mechanics, time is absolute. The parameter occurring in the Schrödinger equation has been directly inherited from Newtonian mechanics and is not turned into an operator. In quantum field theory, time by itself is no longer absolute, but the four-dimensional spacetime is; it constitutes the fixed background structure on which the dynamical fields act. GR is of a very different nature. According to the Einstein equations (2), spacetime is dynamical, acting in a complicated manner with energy momentum of matter and with itself. The concepts of time (spacetime) in quantum theory and GR are thus drastically different and cannot both be fundamentally true." http://www.hindawi.com/journals/isrn/2013/509316/

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