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Quantum particles feel the influence of gravitational fields they never touch

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Re: Quantum particles feel the influence of gravitational fields they never touch

#31
post #27
post #23

Earlier quoted context omitted.

> They measured a bigger gravitational effect on the particle No, they didn't. They measured a phase shift in the particle's wave function. There is no "gravitational force" in free fall, and the particles were in free fall. > gravity decreases with distance squared The Newtonian gravitational force does, but the Newtonian gravitational force is irrelevant for an experiment conducted in free fall, as this one was. Th…

>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 One path of the particle in superposition was closer to the 1.25Kg mass than the other path, and they did measure a difference when doing that. I don't know if you are trying to be pedantic, or just want to contradict. I know what you are saying, but the the exp…

> they did measure a difference

They measured a phase shift in the wave function, as I said. They did not measure any direct difference in "gravitational effect" on the particles, as for example a difference in bending of their trajectories due to the source mass would be.

> the expression "not touching the field" makes perfect sense to me

The problem with it, as several commenters have pointed out, is that you can't shield anything from gravity. The "not touching the field" comes from electromagnetism, where you can shield things from the field. So the "not touching the field" interpretation, while it works for EM, does not work for gravity.

Re: Quantum particles feel the influence of gravitational fields they never touch

#32
post #23
post #20

Earlier quoted context omitted.

They measured a bigger gravitational effect on the particle, because the superpositional pair of the particle flew closer to a mass than the actually measured particle. Regarding the "never touch", gravity decreases with distance squared, so it diminishes quickly with distance. There is a big difference in being near the mass, as opposed to feeling the dimished effect of it from far.

> They measured a bigger gravitational effect on the particle No, they didn't. They measured a phase shift in the particle's wave function. There is no "gravitational force" in free fall, and the particles were in free fall. > gravity decreases with distance squared The Newtonian gravitational force does, but the Newtonian gravitational force is irrelevant for an experiment conducted in free fall, as this one was. Th…

> There is no "gravitational force" in free fall, and the particles were in free fall.

what is free fall in a reference frame is a particle subject to a force in another reference frame.

Re: Quantum particles feel the influence of gravitational fields they never touch

#33
post #22
post #8

Earlier quoted context omitted.

They touch on that in the article: > Notably, the particles weren’t in a gravitational field–free zone. Instead, the experiment was designed so that the researchers could filter out the effects of gravitational forces, laying bare the eerie Aharonov-Bohm influence. I'm no physicist, but I think they calculated the expected influence and compared that with a measurement.

The "filter out the effects of gravitational forces" means that the measured particles were in free fall; in free fall there is no gravitational force.

Is that the common way you'd express that they were measured in free fall -- that the effects were "filtered" out? That seems like an odd way of saying it, but I'm not a physicist.

Re: Quantum particles feel the influence of gravitational fields they never touch

#34

Earlier quoted context omitted.

You're about a hundred years late to be making this stand. I've never actually seen anyone claim that quantum physics in general is hooey. What do you even mean by that? That in fact, all of modern physics observations, as well as cosmology, materials science, etc, can actually be explained by classical physics? Or do you mean that you think there is some underlying classical/deterministic process which drives nature…

[dead]

OK, Mr Troll. That site is like I had a seizure while playing with Adobe Dreamweaver.

Re: Quantum particles feel the influence of gravitational fields they never touch

#35

I don't see the new. All this tells me is that entangled particles react to things that impact some but not all of their various superpositions/entanglements. Sounds like basic double-slit stuff to me. The particle that goes through the slit A reacts to its partners going through slit B. The particle that passed through gravity field A reacted to its partners going through field B.

Quantum mechanics news hasn't been giving us anything new for decades. Every modern article is about a new speculation, or at best an or experiment that reconfirms what we already knew. Yet, articles will never cease to use click-bait to make you think a revolution has occurred.

Re: Quantum particles feel the influence of gravitational fields they never touch

#37
(Per the article): Is it correct to describe superposition as the probability of, e.g., an electron being in one of two places? In such an example, is it instead correct to say that superposition is a probability distribution of infinitely many possible locations?

Re: Quantum particles feel the influence of gravitational fields they never touch

#38

I know this is a trope that comes up in half of the posts involving a journal article, but scientific journal pricing is so confusing to me. I can pay $30 for digital access to a 4 page article (it says Vol 375 pg 226-229). Or I can pay $15 and get the entire issue of Vol 375 in print? Or I can pay $80/yr to join AAAS and get "50 issues of Science", but which issues? I assume they mean the upcoming year of issues, bu…

Just use sci-hub. It always works, and it's very easy. There's no good reason to give the journal your money to read an article they had no hand in writing or funding.

Re: Quantum particles feel the influence of gravitational fields they never touch

#39
post #35

I don't see the new. All this tells me is that entangled particles react to things that impact some but not all of their various superpositions/entanglements. Sounds like basic double-slit stuff to me. The particle that goes through the slit A reacts to its partners going through slit B. The particle that passed through gravity field A reacted to its partners going through field B.

Quantum mechanics news hasn't been giving us anything new for decades. Every modern article is about a new speculation, or at best an or experiment that reconfirms what we already knew. Yet, articles will never cease to use click-bait to make you think a revolution has occurred.

The closer you can get the words "quantum" and "gravity" together in the title the better.
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