22nd International Conference on General Relativity and Gravitation

I am attending GR22 in Valencia Spain, to present a poster and also take part in the talks. I will be presenting a poster based on this paper (soon to be published) from a talk I gave at DICE2018.

What the paper and poster argue is that in the BMV experiment, observing entanglement is not enough to show that gravity is quantum. I do this by showing that a classical gravitational field coupled to the Bohmian trajectories of the individual particles will show entanglement.

The conference looks like its going to be interesting to attend.

The image at the top shows 4 runs of the BMV experiment, with all 4 Bohmian particle trajectory combinations shown. There is entanglement generated 1/4 of the time, when the experiment happens to look like the 2nd diagram from the left.

The poster is 90 x 200cm, available in real 3D, if you visit Valencia From July 7-12 2019 :-)

The BMV experiment sets out to show that gravity is quantized. If gravity is quantized, we expect to be able to form a gravitational field into a superposition, so that fundamentally the gravitational field is not certain at one spacetime point. Trying to come up with a theory of gravity that can be in a quantum superposition, while still working for all present tests of Einstein’s General Relativity has proved impossible so far, despite thousands of very smart people working over 50 years on the problem.

Perhaps gravity cannot be quantized. With Bohmian trajectory gravity, gravity is not quantized and has a well-defined connection to the sub-atomic particles.

If gravity is not quantized, all sorts of assumptions about quantum mechanics suddenly fail, as an unquantized gravity allows one to cheat behind the back of quantum mechanics. This is a large part of the reason why many people think gravity must be quantized. I’m not in the gravity must be quantized group, mostly because I think it just won’t work.

Quantum statistics in Bohmian trajectory gravity-T C Andersen 2019 J. Phys.: Conf. Ser. 1275 012038 – 9th International Workshop DICE2018 : Spacetime – Matter – Quantum Mechanics Abstract. The recent experimental proposals by Bose et al. and Marletto et al. (BMV) outline a way to test for the quantum nature of gravity by measuring gravitationally induced differential phase accumulation over the superposed paths of […]

Gravitation finally meets Quantum Mechanics in experiments-I think that the biggest news in a while in quantum mechanics is newly forming ability of experimenters to do quantum experiments with gravity. A fine example of an experiment already done is Phase Shift in an Atom Interferometer due to Spacetime Curvature across its Wave Function by Asenbaum et al. They conclude: Therefore, the phase shift […]

GR = QM – Susskind & I agree :)-So Leonard Susskind publishes a paper on arXiv Dear Qubitzers, GR=QM Which of course is what I have been saying all along. Of course Susskind’s paper is actually ‘of course’ not about QM emerging from GR, which is what I believe, and have good reason to follow up on. Instead Susskind says: Dear Qubitzers, GR=QM? […]

Rings coalescing-As someone pointed out on reddit, it looks like an inelastic collision. Singularities, de Broglie and emergent quantum mechanics comes to mind for me. The interaction causes a wave to propagate. After a time equal to the period of a wave on the ring, it separates into two. https://file.scirp.org/pdf/ACES_2013100819104983.pdf When I saw this gif I […]

Important New Book – Theo van Holten-The Atomic World Spooky? It Ain’t Necessarily So!: Emergent Quantum Mechanics, How the Classical Laws of Nature Can Conspire to Cause Quantum-Like Behaviour by Theo van Holten The hardcover is out – for example here: Amazon.com or at Springer – but its coming out in paperback soon – Amazon.ca . Its not coming in paperback, so […]

Adam Helfer – Black hole evaporation? – the trans-Planckian problem-I have been reading up on the trans-Planckian problem with the black hole evaporation process. (See the end for an update in March 2018) Here is the problem. An observer far away from a black hole sees photons of normal infared or radio wave energies coming from a black hole (i.e. << 1eV). If one […]