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Hello,

I'm happy to have come across this forum. I've been spending some time looking at other posts, and it occurs to me that this is a good place to post a question that has been gnawing on my brain for a few months.

I think the answer is that we don't yet know. But in case there's a better answer, here we go:

When two particles/photons/quanta/whatever are entangled and then separated, is it possible that they feel an attraction towards one another?

I'm not talking about the electrical attraction they will have if oppositely-charged, or the normal gravitational attraction between all particles. I'm wondering if there is a gravity-like attraction acting specifically between entangled quanta.

The reason that this has been on my mind is that it occurred to me that if the universe was a singularity at the instant before the big bang, then all particles in the universe were in fact entangled at that time, and still would be today. Such a thing might be exactly what gives rise to gravity, and would go a long ways towards defining the Grand Unified Theory.

This would explain how gravity works over infinite distances, and would bring it squarely into the testable realm.

Any thoughts?

Wayne

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Hi Wayne,

Welcome aboard. This site is moderated so you don't get lots of nonsense so it is a good place to have a discussion.

Attraction, as we know think of it is due to the exchange of certain types of particles. Electrical attraction is due to the exchange of photons. The way it works is somewhat like two basketball players both attempting to grab the same ball. This exchange of pleasentries causes attraction.

Repulsion can be likened to another type oof ball game. Think of two people tossing a large medicine ball back and forth. Each time one of the players catches the thing they have to step back.

I just realized that I am late for an appointment - more tomorrow.

Dr. R.

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Hi Wayne,

Sorry to be so abrupt yesterday.

Attractive (and also repulsive) forces are due to the exchange of certain types of particles. Gravitation is due to the exchange of gravitons. This is, of course, related to the amount of mass that an object has. The mass of a particle, hence its gravity, depend on something called the Higgs field and its quantization called the Higgs boson. This is the only part of the Standard Model of particle physics that has not been observed. The hope is that the Large Hadron Collider (LHC) will show a particular interaction that would indicate the existence of Higgs. (Keep your fingers crossed!)

You asked: "is a gravity-like attraction acting specifically between entangled quanta"?

I won't just say no. Entanglement is what Einstein called "Spukhafte Fernwirkung" i.e., "spooky action at a distance". This sort of entanglement is not like a tangled ball of yarn where a tug on one part makes a tug on another. It speaks more to a phase relation between the wave functions that describe two systems. Einstein and his freinds Podalski and Rosen devised what is known as the EPR paradox in an attempt to show that quantum theory is incomplete. Well that didn't work out. It turns out that QM is nonlocal and there is no real paradox. Entanglement is commonplace and there are certainly aspects of it involved in Higgs. So the answer to your question is sort of no. Does that help? wink


For more on EPR the original paper is:

http://prola.aps.org/abstract/PR/v47/i10/p777_1

also:

http://ej.iop.org/links/rbKdhc0Tq/9vSVOyfB2xG_DvKBav5vpA/ej91n6.pdf

For more on exchange forces see:

http://pos.sissa.it//archive/conferences/037/002/EMC2006_002.pdf


http://upscale.physics.utoronto.ca/PVB/Harrison/HighEnergy/HighEnergy.pdf


http://hyperphysics.phy-astr.gsu.edu/hbase/forces/exchg.html#c1


Dr. R.

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Dr. R,
Your second link leads to a 404 Not found error. Do you have another?

The rest of your links were all very interesting.

"Amaranth"


If you don't care for reality, just wait a while; another will be along shortly. --A Rose

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Hi Amaranth,

Sorry about that.

The paper that I am referring to is:

Comment on `Is the EPR paradox really a paradox?'
Roland Onm?s
Eur. J. Phys. 20 No 1 (January 1999)

The link IOP gave me was as stated above, however when I check today it is

http://ej.iop.org/links/rk2vUV38n/3k22oqPC2xGG8zlzav5vpA/ej91n6.pdf

This is a little different. If this link is not good then go to:

http://ej.iop.org

then click on the search tab, and search for the author.

For still more info on EPR you could search for EPR directly on the same page. A good example is:

Questioning the quark model. Strong interaction, gravitation and time arrows. An approach to asymptotic freedom
G. Basini and S. Capozziello
Europhys. Lett. 63 No 5 (September 2003) 635-641

or

One less quantum mystery
A F Kracklauer
J. Opt. B: Quantum Semiclass. Opt. 4 No 4 (August 2002) S469-S472

These article are free and so anyone should be able to download them.

Again, my apologies.

Dr. R.





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I'm still getting a "not found" error. On the first link. Doesn't look hopeful.

"Amaranth"


If you don't care for reality, just wait a while; another will be along shortly. --A Rose

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Sorry to disappoint you, but there no such thing as "entanglement".
This must not stop you from creating innovative ideas.
Plenty of big shots in Physics have fallen into this trap!

es

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Once again ES you distinguish yourself by imitating Shakespeare. What was that he said about "sound and fury?"

Entanglement is fact.
Entanglement is reality.
That you refuse to accept it,
Or are unable to understand it,
Is not going to change nature.

Anytime you don't like that assessment feel free to provide an alternative explanation for Bell's inequality. Supporting matrix math calculations required.

So far no one has claimed the Nobel Prize that would most certainly be earned by anyone that can do it. Perhaps it will be yours.


DA Morgan
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I do not think one can get nowadays any prize by pointing to the stupidity of pseudoscience bureaucracy.

Just insults from ignoramuses, you get for doing so.

e:)s

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You complain about anything and everything related to the most accurate theory ever devised to explain objective reality.

Not a single person of my acquaintance with a PhD would agree with anything you've written so far on the subject.

You are not going to overthrow that theory with proclamations at SAGG. If you have an alternative explanation for Bell's Inequality post it along with the supporting math.

If not consider that maybe you are complaining about something you don't understand.

It isn't a bad thing to not understand something. There are a zillion things I don't understand.

But it is a problem when you declare them false based upon said lack of understanding.

The truth is that anyone that can overturn QM will get a Nobel. Same goes for whoever overturns General or Special Relativity.


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BELL's theorem:No physical theory of local hidden variables can ever reproduce all of the predictions of quantum mechanics

That is correct.
Do not pretend, that I am opposed to QM.
My considerations are BASED ON QM.

The QM is not saying the things you put in its mouth.

The QM, the real one, does not say anything about entaglement.
The claims to opposite are 100% false.

es

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Got rid of the duplicate post for you es.

You write:
"The QM, the real one, does not say anything about entaglement."

And next you are going to say that it says nothing about quantum computers either?

You can not separate the two. And it would seem that a lot of people would agree with me on that.

http://www.faqs.org/faqs/physics-faq/measurement-in-qm/
http://www.lepp.cornell.edu/spr/2000-03/msg0023368.html
http://arxiv.org/ftp/cs/papers/0508/0508059.pdf
http://www.physics.rutgers.edu/~coleman/501.html
http://rockpile.phys.virginia.edu/mod04/mod24.pdf - Similar pages
http://www.lns.cornell.edu/spr/2006-01/msg0072788.html
http://www.lsr.ph.ic.ac.uk/~kinsle/QO/thirdom1995/kinsler-1995nqec.pdf
http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=4621261
http://www.physics.emich.edu/nsharma/resume.htm

The list I could post is nearly endless.

You truly seem to be on a tear about QM without a thing to back up your statements other than the appearance that you don't understand the subject such as your statement, above, that QM has nothing to do with Bell's Inequality. It would seem that a substantial number of physicists would disagree.


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You are professional ignoramus.

Nothing will help you, ever !

e:S

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So, anyway, to return to the question at hand...

It was my understanding that gravitational attraction is theorized to be due to A) The warp of space and/or B) An exchange of particles. (This being one major difference between QM and General Relativity.)

That gravity COULD be caused by something other than particle exchange tells me that perhaps the truth lies somewhere between QM and GR. If QM relies on an exchange of particles for gravitational attraction, but gravity works at infinite distance, then that implies that every particle in the universe is somehow constantly emitting an infinite number of gravitons in an infinity of directions in order to exchange gravitons with every other particle in the universe - something that doesn't sound quite right since that would also give everything an infinite amount of gravitational pull, meaning every quanta in the universe would be a black hole. Obviously, that's not the case.

Warped space certainly seems to exist - as seen by the gravitational effect on light, and as will soon very likely be proven by the research on frame-dragging by Gravity Probe B. But it still seems unlikely that the tiny warp of space caused by a hydrogen atom could stretch all the way out across light years to effect the path of another hydrogen atom. If it doesn't, then gravity doesn't have an infinite reach. But if it does, then it seems that you'd be stuck with every particle creating an infinite amount of warp and thus, again, being a black hole.

But, if all the particles in the universe are already entangled by virtue of having been a singularity at the universe's birth, then they all do have that one thing in common and that could explain how gravity can have an infinite reach without particles emitting infinite numbers of gravitons and without space being infinitely warped.

(Sorry ES, I'm sure you probably do know one heckuvalot more about QM - and General Relativity - than me, and I would rarely hesitate to defer to somebody else in a discussion like this, but I'm firmly IN the "entanglement-exists" camp. If you can provide a different explanation for spooky action at a distance, I'm all ears.)

I'm well aware of significant gaps in my understanding, but the infinite reach of gravity and its weak nature seem to me to be a major contradiction. The idea of entanglement from the big bang being the source of gravity seems to solve it quite nicely, but that an armchair physics fan like myself could come up with it implies to me that it's probably WAY off. On the other hand, a Nobel Prize would look awfully nice on my mantle. wink

W

[edited for a couple typos and to clarify a few poorly-worded sentences.]

Last edited by Wayne Zeller; 02/24/07 07:16 AM.
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Well thought out Wayne. And unfortunately es seems to know and care little about QM. While he has unrelentlessly railed against it he has never once, as I recall, actually provided a link that supporting his contrarian point-of-view.

I would like to explore your post more but I don't want to just slash and burn so here's something I'd like you to consider.

You wrote:
"If QM relies on an exchange of particles for gravitational attraction, but gravity works at infinite distance, then that implies that every particle in the universe is somehow constantly emitting an infinite number of gravitons in an infinity of directions in order to exchange gravitons with every other particle in the universe - something that doesn't sound quite right since that would also give everything an infinite amount of gravitational pull"

Now re-read your paragraph substituting the word "photon" for the word "graviton" and substituting "electromagnetic" for "gravitational."

Does one create a problem for you and the other not?

Fact: We know the sun does not emit an infinite number of photons.

Fact: We know the light from the sun works at vast distances.

Can you find the logical error in what you wrote?


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Excellently put. Thanks.

My mistake was in thinking of gravitons as particles and not as waves. Just as the photons from the sun expand as waves and constantly propagate as they spread, graviton waves would do the same. And, just as a birthday cake candle would be visible from light years away given a big enough telescope, the gravitons from a single particle will be detectable light years away given a sensitive enough detector. So it scales down from the sun to a particle.

That makes a lot of sense.

Here's where I still have conceptual trouble with it: When a photon hits something, it reflects (or refracts) and this is its interaction. If that something happens to be an eyeball, then we see it. In that interaction, the photon is stopped from continuing on it's way. If it isn't stopped, then the thing it hit was transparent to it and it is undetectable and thus unmeasureable. It would seem, though, that the same doesn't hold true for gravitons. Gravitons interact with every particle they hit, but then keep on going - totally unaffected, it would seem, by the interaction. Otherwise, the sun would (for example) exert no "downward" pull on people on the nightside of Earth. It's already exerting it's pull on the Earth itself, and yet the gravitons travel right on through and pull on the things on the opposite side of the Earth and then just keep right on going through infinity, interacting with everything they encounter and yet remaining unchanged in the interaction.

The universe is completely transparent to them and yet reacts to them at the same time. How is that possible?

Also, if gravitons travel and propagate as waves, that implies a wavelength and amplitude. Presumably, the amplitude decreases over distance and is what varies inversely with the square of distance between two particles. So what is the wavelength? If two bodies are moving away from one another then redshift is going to lengthen the wavelength and if they are approaching one another then there will be blue shift shortening the wavelength. But what does that mean in terms of gravity? What happens if you get "zapped" with an extremely shortwave pulse of gravity? Does such a question even have a meaning?

I definitely feel like I learned something today: I can tell because I suddenly have so much less understanding.

W

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Lets take your problem with gravitons and return to photons.

Photons, as you will likely recall, are the force carrier for the electromagnetic force.

Take a strong bar magnet and put it onto a table.
2 inches away put a small nail.
Behind that put another small nail.
Move the magnet toward the nails.
Does one shield the other?

I wish I could offer you more than just analogies but the truth is that no one fully understands it and I don't pretend to understand as much as some (well many). Just a bit more than my step-daughter and by the time she completes her PhD no doubt I will have become quaint (if I'm lucky).

The best I can do for you here is to remind you that it is quite possible that there are more than 3 spatial dimensions and that gravity likely acts across all of them. What we are seeing is just part of the picture.


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Originally Posted By: Wayne Zeller
Says,

.................... if the universe was a singularity at the instant before the big bang, then all particles in the universe were in fact entangled at that time, and still would be today. Such a thing might be exactly what gives rise to gravity, and would go a long ways towards defining the Grand Unified Theory.

This would explain how gravity works over infinite distances, and would bring it squarely into the testable realm.

Wayne


Nice idea Wayne, for the explanation of Gravity.
But its very unlikely to be true.
Since if it was, ...then a test taken on ANY (two) pairs of electrons, should test positive for entanglement in the Laboratory.
Which they do not.

Electron or other quantum entanglement, only works when both quanta come from the same source. i.e from the same filament, the same light source, or the same electron beam. Or a structure for generating Einstein-Podolsky-Rosen electron pairs, (where electron electron spin is investigated)
It is only when electrons are recorded and then optically 'split' by the same equipment, and then allowed to travel on in different directions, that they are found to be entangled.

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"You will never find a real Human being - even in a mirror." .....Mike Kremer.
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Originally Posted By: Mike Kremer
if it was, ...then a test taken on ANY (two) pairs of electrons, should test positive for entanglement in the Laboratory.Which they do not.


It was my understanding that the more particles you entangle, the less each changes when others are measured. If all particles in the universe were entangled, then the change on one when another is measured would be infinitesimal. We'd never be able to detect it directly without measuring half the particles in the universe, which ain't gonna happen.

However, I can now see how the concept of >3D gravitonic waves gets around what I thought were inconsistencies.

Still though, even if it isn't the cause of any known phenomena, I wonder about universal entanglement. If the universe started as a singularity, then wouldn't all the particles in it be entangled? How does a particle get disentangled? Assuming that they were all entangled for at least the first instant of the big bang, is that entanglement being taken into account in cosmological studies of how the universe started? It hardly seems like a dismissable idea.

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Originally Posted By: Wayne Zeller
Originally Posted By: Mike Kremer
if it was, ...then a test taken on ANY (two) pairs of electrons, should test positive for entanglement in the Laboratory.Which they do not.


It was my understanding that the more particles you entangle, the less each changes when others are measured. If all particles in the universe were entangled, then the change on one when another is measured would be infinitesimal. We'd never be able to detect it directly without measuring half the particles in the universe, which ain't gonna happen.

However, I can now see how the concept of >3D gravitonic waves gets around what I thought were inconsistencies.

Still though, even if it isn't the cause of any known phenomena, I wonder about universal entanglement. If the universe started as a singularity, then wouldn't all the particles in it be entangled? How does a particle get disentangled? Assuming that they were all entangled for at least the first instant of the big bang, is that entanglement being taken into account in cosmological studies of how the universe started? It hardly seems like a dismissable idea.

m


Hi Wayne,

Your point - That entanglement at Singularity, sounds logical.
Then again - would'nt dis-entanglement during Big Bang, be just as logical?

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"You will never find a real Human being - Even in a mirror." ....Mike Kremer.


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