Posted on 08/24/2011 2:52:57 PM PDT by Red Badger
The way gravity effects quantum particles proves that it cannot be an emergent phenomenon, says physicist.
One of the most exciting ideas in modern physics is that gravity is not a traditional force, like electromagnetic or nuclear forces. Instead, it is an emergent phenomenon that merely looks like a traditional force.
This approach has been championed by Erik Verlinde at the University of Amsterdam who put forward the idea in 2010. He suggested that gravity is merely a manifestation of entropy in the Universe, which always increases according to the second law of thermodynamics. This causes matter distribute itself in a way that maximises entropy. And the effect of this redistribution looks like a force which we call gravity.
Much of the excitement over Verlinde's idea is that it provides a way to reconcile the contradictions between gravity, which works on a large scale, and quantum mechanics, which works on a tiny scale.
The key idea is that gravity is essentially a statistical effect. As long as each particle is influenced by a statistically large number of other particles, gravity emerges. That's why it's a large-scale phenomenon.
But today, Archil Kobakhidze at The University of Melbourne in Australia points to a serious problem with this approach. He naturally asks how gravity can influence quantum particles.
Kobakhidze argues that since each quantum particle must be described by a large number of other particles, this leads to a particular equation that describes the effect of gravity.
But here's the thing: the conventional view of gravity leads to a different equation.
In other words, the emergent and traditional views of gravity make different predictions about the gravitational force a quantum particle ought to experience. And that opens the way for an experimental test.
As it happens, physicists have been measuring the force of gravity on neutrons for ten yeas or so. And...wait for the drum roll... the results exactly match the predictions of traditional gravitational theory, says Kobakhidze.
"Experiments on gravitational bound states of neutrons unambiguously disprove the entropic origin of gravitation," he says.
That's an impressive piece of physics. It'll be interesting to see how Verlinde and his supporters respond.
Ref: arxiv.org/abs/1108.4161: Once More: Gravity Is Not An Entropic Force
Gravity is merely the effect of everything growing larger.
So, I still have to go to work tomorrow?
I had a thought about why time dilation and velocity are linked in Relativity. Imagine that time is caused by our 3 dimensional universe moving at the speed of light through a 4th dimension. We move through this 4th dimension at a constant rate and direction, which is why time seems to flow one-way at a contant rate. The kicker to this idea is, that the velocity limit of the speed of light applies to the SUM of our motion in the 3 spatial dimensions and the 4th time dimension. So, any spatial motion would have to reduce the velocity of an object through time, since everything is already moving at the speed of light in the 4th dimension. Of course, this effect wouldn’t be noticeable at everyday speeds, since they are so much smaller than the speed of light, the time distortion is negligible.
I’m still trying to work out a few things about how that could actually work, but I think it’s an interesting idea.
My guess was that it is a property of dark matter.
It is probably best to just watch and enjoy “Star Trek” rather than think too much about it.
They do make some weak attempts to explain why everyone speaks American English but that has to be a big what if too.
They still teach it at the colleges. I talked to a professor at the local college (because I wanted to know if he taught a class on quantum.) that didn't believe in Quantum physics at all!
If it's now considered bunk, then why the heck are students still forced to take it and pay for it?
Would your wife describe it as a phenomenon?
I don't know what your local college is, but there is no mainstream Physicist who doesn't believe in QM. None.
So does this mean that there are gravitons in the universe?
Really? Beside that one professor, at the beginning of almost every book I've read on the subject, there's always a quiet "debate" between the two sciences, as if there's some kind of scientific struggle going on behind the scenes.
I'm glad you told me that. I'm not a science major, but Quantum physics fascinates me. I'm thrilled to learn there is no more debate. It's an amazing science, but when I try to explain it to some one, the scientific jargon escapes me. (I'm not well versed in that at all.)
At a certain age, just “emergent” is enough.
Okay . It has been long been my belief, and I am NOT a physicist, but I do watch the Science Channel and all. But it is my belief that gravity is NOT a property of matter, but matter is a property of gravity. When you look at it that way, everything changes.
I would like you to take a look at my book if you have any leisure time.
Bigheadfred's Incoherent And Incomprehensible Rantography
A Poem (by me)
Dear Mr. Buffett:
Shuffett.
thanks. i think relativity, as popularly expressed, is mental masturbation.
I know what you mean, but does everybody else????
Maybe the folks behind this theory are quarks!
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