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Quantum particles can feel the influence of gravitational fields they never touch

#1
C C Offline
https://www.sciencenews.org/article/quan...ohm-effect

EXCERPT: . . . in quantum physics, particles can feel the influence of magnetic fields that they never come into direct contact with. Now scientists have shown that this eerie quantum effect holds not just for magnetic fields, but for gravity too — and it’s no superstition.

Usually, to feel the influence of a magnetic field, a particle would have to pass through it. But in 1959, physicists Yakir Aharonov and David Bohm predicted that, in a specific scenario, the conventional wisdom would fail. A magnetic field contained within a cylindrical region can affect particles — electrons, in their example — that never enter the cylinder. In this scenario, the electrons don’t have well-defined locations, but are in “superpositions,” quantum states described by the odds of a particle materializing in two different places. Each fractured particle simultaneously takes two different paths around the magnetic cylinder. Despite never touching the electrons, and hence exerting no force on them, the magnetic field shifts the pattern of where particles are found at the end of this journey, as various experiments have confirmed.

In the new experiment, the same uncanny physics is at play for gravitational fields, physicists report in the Jan. 14 Science. “Every time I look at this experiment, I’m like, ‘It’s amazing that nature is that way,’” says physicist Mark Kasevich of Stanford University... (MORE - missing details)
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#2
Kornee Offline
(Jan 14, 2022 05:04 PM)C C Wrote: https://www.sciencenews.org/article/quan...ohm-effect

EXCERPT: . . . in quantum physics, particles can feel the influence of magnetic fields that they never come into direct contact with. Now scientists have shown that this eerie quantum effect holds not just for magnetic fields, but for gravity too — and it’s no superstition.

Usually, to feel the influence of a magnetic field, a particle would have to pass through it. But in 1959, physicists Yakir Aharonov and David Bohm predicted that, in a specific scenario, the conventional wisdom would fail. A magnetic field contained within a cylindrical region can affect particles — electrons, in their example — that never enter the cylinder. In this scenario, the electrons don’t have well-defined locations, but are in “superpositions,” quantum states described by the odds of a particle materializing in two different places. Each fractured particle simultaneously takes two different paths around the magnetic cylinder. Despite never touching the electrons, and hence exerting no force on them, the magnetic field shifts the pattern of where particles are found at the end of this journey, as various experiments have confirmed.

In the new experiment, the same uncanny physics is at play for gravitational fields, physicists report in the Jan. 14 Science. “Every time I look at this experiment, I’m like, ‘It’s amazing that nature is that way,’” says physicist Mark Kasevich of Stanford University... (MORE - missing details)

No and no. The relevant passage from above linked article, with highlight added:

At the top of the vacuum chamber, the researchers placed a hunk of tungsten with a mass of 1.25 kilograms. To isolate the Aharonov-Bohm effect, the scientists performed the same experiment with and without this mass, and for two different sets of launched atoms, one which flew close to the mass, and the other lower. Each of those two sets of atoms were split into superpositions, with one path traveling closer to the mass than the other, separated by about 25 centimeters. Other sets of atoms, with superpositions split across smaller distances, rounded out the crew. Comparing how the various sets of atoms interfered, both with and without the tungsten mass, teased out a phase shift that was not due to the gravitational force. Instead, that tweak was from time dilation, a feature of Einstein’s theory of gravity, general relativity, which causes time to pass more slowly close to a massive object.

Well exactly! A purely classical GR effect. Operating on any system - classical or quantum. Equally. No gravitational AB going on there. Sure it's presumably the gravitational potential not it's gradient ('gravitational force') creating the phase shifts.
But that is not in any sense equivalent to the magnetic AB phase shift, which has no classical analog - despite long standing counterexamples/counterclaims by one physicist likely now expired.

Moreover a true gravitational analog to AB would involve spinning mass, generating a gravito-magnetic field and associated vector potential. But it would likely be far too feeble to ever be detected in a lab experiment. Not to mention that unlike with AB where a current-carrying solenoid or magnetized wire generates an external A field without any E field present, there is no true gravitational equivalent since there is only one sign of 'gravitational charge'. 'Filtering out' of gravitostatic field is only possible in the case of special geometry - hollow interior region of a spherical shell of matter.

Actually the less inappropriate analog would involve the Aharonov-Casher effect, relating to motion of a neutral particle magnetic moment in an applied static E field, not the AB effect owing to magnetic vector potential. But would still be wrong as already explained.

Unfortunately the blunder cannot be put down to journalistic license - here it's the physicists involved confusing what should have been a pretty clear cut demarcation.
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