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a reply to: Arbitrageur

I agree. But even going the gedanken route requires that you frame a hypothesis coherently if you want to share your ideas. People are not mind readers.

And just in my own mind, gedanken is useful for ideas which have little hard evidence to back them up - which is fine - because you can always design experiments. But the nature of light, photons, EM - this all has a multitude of evidence which demonstrate how they function in our world. That's not to say we know everything. But if you're going to cancel out all fundamental data acquired over two centuries, you better have a rap sheet to go along with it that explains why you want to do that.

originally posted by: Phantom423


And what happens if this smart person doesen't agree with you? What if he/she says "where's your evidence, what experimental data do you have?" Are you going to be insulted and walk out?

I think you're making some very lofty assumptions that just because someone is "smart" by your standards, that this person is even going to engage in a conversation with you on a topic that you can't even frame in a simple hypothesis.

They will have no choice but to agree with me, because they would be agreeing with reality. It would be a succession of aha and eureka moments. They would see more clearly the disagreements contained in their own mind, and then this would all be happening multiple ways and times and varying degrees, we would be working towards honing in on the most likely candidate for truth.

Well that guy, Nima Arkani Hamed, would be perfect.

a reply to: ImaFungi

I sincerely can't tell if you're trolling or not.

originally posted by: ImaFungi
Well that guy, Nima Arkani Hamed, would be perfect.

Peter Woit has high praise for him, but he also said this about Hamed:

www.math.columbia.edu...

he knows exactly what he thinks and will tell you forcefully what you should think.

He's spent many years developing the ideas he has now and I'd be very surprised if 5 hours in front of a blackboard with anybody would turn those views upside-down. Reading a new paper about a revolutionary new experimental result might do it.

originally posted by: Arbitrageur

originally posted by: ImaFungi
Well that guy, Nima Arkani Hamed, would be perfect.

Peter Woit has high praise for him, but he also said this about Hamed:

www.math.columbia.edu...

he knows exactly what he thinks and will tell you forcefully what you should think.

He's spent many years developing the ideas he has now and I'd be very surprised if 5 hours in front of a blackboard with anybody would turn those views upside-down. Reading a new paper about a revolutionary new experimental result might do it.

Not turn views upside down. Connect things, open up things, eliminate things, process things, light paths of things, progress towards knowing unknown things etc.

a reply to: Arbitrageur

Plenty, plenty, many many many people are doing it your way and failing.

I am not asking for much, to be me my way, and succeed.

Genius is exception to the rule

originally posted by: Arbitrageur
Peter Woit has high praise for him, but he also said this about Hamed:

That writing is from 2013. We are a nice amount into 2015. Remember, geniuses can gain a lot of intelligence in 2 years.

Considering the red-shift, is the universe being pulled/stretched by some yet unknown force?

a reply to: Coagula
We call it dark energy and our best guess at this point is that the accelerating expansion is due to the cosmological constant aka "Vacuum energy", but we have no models to predict the observed values. We think the evidence for such a "push" to the metric expansion of space is pretty good.

There have also been claims of "dark flow" which is supposedly a "pull" force in certain specific directions but these claims have been disputed and aren't confirmed as far as I know.

originally posted by: ImaFungi
a reply to: Arbitrageur

Plenty, plenty, many many many people are doing it your way and failing.

All the amazing technology we have today results from working models so I don't see how that's a failure. It seems to me like we're very successful.

However nobody I know of would argue that our models are perfect or have no room for improvement; nonetheless, they work pretty darn well.

a reply to: ImaFungi

I agree I don't think the Higgs boson was what we thought it was I'm leaning towards them being techni quarks since this model can actually explain dark matter. The Higgs on the other hand has no benefits to our understanding of the unverse and has zero benefits. The Higgs model doesn't give any true insight.

a reply to: dragonridr
The main issue I had with his logic is an objection so common he addressed it specifically: why throw the old model out if you have nothing better to replace it with? Then he brings up the epicycles example and suggests that we may be doing the equivalent of refining epicycles in particle physics. Even if this is so, if you follow through with this analogy, how did we get rid of the epicycles model? We showed it was wrong and came up with a better model, which to me kind of defeats his analogy in saying we should throw out the current model before we have a better one.

So of course, who wasn't fine with throwing out epicycles in favor of the better model, and who wouldn't rather have a model that predicts all the things he points out our current model fails to predict? Of course we would like that.

The other noteworthy comment on this topic is that pointing out flaws with our models by itself doesn't support any alternative model. Nobody is stopping folks like Garrett Lisi from proposing alternate models of particle physics, but he's the first person to admit that alternate models such as his are long shots at best, and are probably wrong.

originally posted by: Arbitrageur
a reply to: dragonridr
The main issue I had with his logic is an objection so common he addressed it specifically: why throw the old model out if you have nothing better to replace it with? Then he brings up the epicycles example and suggests that we may be doing the equivalent of refining epicycles in particle physics. Even if this is so, if you follow through with this analogy, how did we get rid of the epicycles model? We showed it was wrong and came up with a better model, which to me kind of defeats his analogy in saying we should throw out the current model before we have a better one.

So of course, who wasn't fine with throwing out epicycles in favor of the better model, and who wouldn't rather have a model that predicts all the things he points out our current model fails to predict? Of course we would like that.

The other noteworthy comment on this topic is that pointing out flaws with our models by itself doesn't support any alternative model. Nobody is stopping folks like Garrett Lisi from proposing alternate models of particle physics, but he's the first person to admit that alternate models such as his are long shots at best, and are probably wrong.

Very true you don't get rid of your old car until you have a new one to replace it. Problem becomes people are real quick to point out what we don't know as proof that somehow we know nothing. Reality is everything is based off experiments create a hypothesis as to why test it. If it holds up than tour on to something. But I still hate the Higgs Boson I argued with people they were giving at a Nobel for an unproven theory. Needless to say I was not popular at work. But it leads no where and thats my problem there is no way to test if a higgs does what we assume it does. If it does than what is the Higgs field why can't we see this energy in any other form. I can't see gravity but I Damn sure can prove it exists. With the Higgs field there is no way to test to see if it's there. I know I'm ranting but it really does poss me off how it was pushed through.

Higgs original gave a wide range for his bosons and even at first it wasn't where he thought it would be. Than came well ok it could also be on this range. OK fine than they find something in that range. OK fine what is it well it must be the Higgs we were looking for right?? Well how do you know well it was supposed to be there. It's like having a wolf in a cow pasture and saying well it must be a cow it's in a cow pasture.

Is it possible to transfer momentum from the quantum vacuum to a molecule? That is the subject of a recent paper on arxiv that's already been submitted to the journal of physics. Here's the paper, and it's abstract:

In a recent publication [1] we have shown using a QED approach
that, in the presence of a magnetic field, the quantum vacuum coupled to a chiral molecule provides a kinetic momentum directed along the magnetic field. Here we explain the physical mechanisms which operate in the transfer of momentum from the vacuum to the molecule. We show that the variation of the molecular kinetic energy originates from the magnetic energy associated with the vacuum correction to the magnetization of the molecule. We carry out a semiclassical calculation of the vacuum momentum and compare the result with the QED calculation.

Some more interesting excerpts:

It is well known that the quantum fluctuations of the electromagnetic (EM) field coupled to electric charges generate an observable interaction energy [2, 3, 4]. The fluctuations which mediate the self-interaction of electrons bound to atomic nuclei give rise to the Lamb shift of atomic levels; the fluctuations which mediate the interaction
between nearby molecules generate van-der-Waals energies; and finally the fluctuations between macroscopic dielectrics generate the Casimir energy. Direct observation of these energies is possible by spectroscopy, atomic interferometry or nanomechanical means [5, 6, 7, 8].

Less well-known is the fact that other observable quantities, functions of the EM field, can be influenced by quantum fluctuations under certain symmetry conditions. That is, when the time-space symmetries of the medium to which the fluctuations couple are compatible with the symmetries of some observable operator, the expectation value of that operator in the vacuum state of the system medium-EM field may take a non-zero value. This is the case of the linear momentum of the EM field when quantum fluctuations couple to a medium in which both parity (P) and
time-reversal (T) symmetries are broken
...

It is a generic phenomenon in field theory that the breakdown of a symmetry is accompanied by a non-zero vacuum expectation value (VEV) of some physical observable associated to the symmetry. In our case the P and T symmetries happen to be broken explicitly by the presence of a chiral molecule and the action of anexternal magnetic field,B0. Correspondingly, a non-zero VEV of the EM momentum shows up in the direction along which the symmetries are broken,B0. The question arises whether it could be possible to take advantage of this phenomenon for practical
purposes. To this end we will show that, due to the conservation of total linearmomentum, there exists necessarily a transfer of kinetic momentum to the chiral molecule of equal magnitude and opposite sign to the VEV of the EM momentum.

Much of the physics in this paper appears to be motivated based on results published by A.Feigel back in 2003, which appears to be on the same lines of harnessing momentum from the quantum vacuum. Just so you guys don't dismiss this as bunk out of hand, that paper has like 109 citations and is published in physical review letters. What do you guys make of this paper? If this is actually valid, then how would this tie in with things like the Em-drive people are trying to build these days?

originally posted by: Diablos
Is it possible to transfer momentum from the quantum vacuum to a molecule? That is the subject of a recent paper on arxiv that's already been submitted to the journal of physics. Here's the paper, and it's abstract:

In a recent publication [1] we have shown using a QED approach
that, in the presence of a magnetic field, the quantum vacuum coupled to a chiral molecule provides a kinetic momentum directed along the magnetic field. Here we explain the physical mechanisms which operate in the transfer of momentum from the vacuum to the molecule. We show that the variation of the molecular kinetic energy originates from the magnetic energy associated with the vacuum correction to the magnetization of the molecule. We carry out a semiclassical calculation of the vacuum momentum and compare the result with the QED calculation.

Some more interesting excerpts:

It is well known that the quantum fluctuations of the electromagnetic (EM) field coupled to electric charges generate an observable interaction energy [2, 3, 4]. The fluctuations which mediate the self-interaction of electrons bound to atomic nuclei give rise to the Lamb shift of atomic levels; the fluctuations which mediate the interaction
between nearby molecules generate van-der-Waals energies; and finally the fluctuations between macroscopic dielectrics generate the Casimir energy. Direct observation of these energies is possible by spectroscopy, atomic interferometry or nanomechanical means [5, 6, 7, 8].

Less well-known is the fact that other observable quantities, functions of the EM field, can be influenced by quantum fluctuations under certain symmetry conditions. That is, when the time-space symmetries of the medium to which the fluctuations couple are compatible with the symmetries of some observable operator, the expectation value of that operator in the vacuum state of the system medium-EM field may take a non-zero value. This is the case of the linear momentum of the EM field when quantum fluctuations couple to a medium in which both parity (P) and
time-reversal (T) symmetries are broken
...

It is a generic phenomenon in field theory that the breakdown of a symmetry is accompanied by a non-zero vacuum expectation value (VEV) of some physical observable associated to the symmetry. In our case the P and T symmetries happen to be broken explicitly by the presence of a chiral molecule and the action of anexternal magnetic field,B0. Correspondingly, a non-zero VEV of the EM momentum shows up in the direction along which the symmetries are broken,B0. The question arises whether it could be possible to take advantage of this phenomenon for practical
purposes. To this end we will show that, due to the conservation of total linearmomentum, there exists necessarily a transfer of kinetic momentum to the chiral molecule of equal magnitude and opposite sign to the VEV of the EM momentum.

Much of the physics in this paper appears to be motivated based on results published by A.Feigel back in 2003, which appears to be on the same lines of harnessing momentum from the quantum vacuum. Just so you guys don't dismiss this as bunk out of hand, that paper has like 109 citations and is published in physical review letters. What do you guys make of this paper? If this is actually valid, then how would this tie in with things like the Em-drive people are trying to build these days?

I look at the paper but looks like they are discussing low temperature decoherence. You know what's we call super conductivity.Fluctuations of local fields cause decoherence of quantum objects. Usually at high temperatures rhe thermal noises are much stronger than quantum fluctuations and undetectable unless the thermal effects are suppressed by certain techniqueslike spin echo.

originally posted by: dragonridr
I look at the paper but looks like they are discussing low temperature decoherence. You know what's we call super conductivity.Fluctuations of local fields cause decoherence of quantum objects. Usually at high temperatures rhe thermal noises are much stronger than quantum fluctuations and undetectable unless the thermal effects are suppressed by certain techniqueslike spin echo.

Hmm, so if the paper is addressing superconductors, then what are the supposed implications? Could this lead to a new more comprehensive understanding of superconductivity? Is this idea, that you can gain momentum from the vacuum, plausible and well motivated? If yes, then wouldn't superconductors become the primary tool for probing for quantum gravity effects? I'm sure there are a number of experiments one can do in this field that would yield much more information about the true nature of the quantum vacuum than using clunky and exorbitantly expensive accelerators.

originally posted by: Diablos
What do you guys make of this paper? If this is actually valid, then how would this tie in with things like the Em-drive people are trying to build these days?

Alders razor says: what cannot be resolved by experiment is not worth debating.

There is some debate in this field, and fortunately I think it can be resolved by experiment, but so far it's still unresolved, and as a result, when you read the Wikipedia article on tech referencing this paper such as this one, it's full of warnings about it not being verified, because, the debate is still going on:

Quantum vacuum plasma thruster

I think the ultimate resolution of the debate must come from experiment. Our models don't decide how nature works, and that paper you asked about describes a model. We have to do experiments to see how nature really works and then refine our models to be consistent with what we observe if necessary. To me it's an open question, and I don't have the bias to claim that Dr. White is wrong as some people do; it's possible but he could also be right. Time will tell.

Here is Dr. White's paper on his anomalous experimental results which is part of the ongoing debate:

Anomalous Thrust Production from an RF Test Device Measured on a Low-Thrust Torsion Pendulum

Before Dr White's paper, I was of the opinion that this paper from NASA summed up the main problem with propellantless propulsion using the dynamic Casimir effect:

Study of Vacuum energy Physics for Breakthrough Propulsion

Unfortunately with the current understanding and materials, the acceleration due to the dynamic Casimir effect is very small, on the edge of measurability.

Dr. White's research seems to challenge that notion, so it will be interesting to see the results of further research on this topic.

I'm sure there are a number of experiments one can do in this field that would yield much more information about the true nature of the quantum vacuum than using clunky and exorbitantly expensive accelerators.

That's part of Dr. White's research:

Study of Vacuum Energy Physics for Breakthrough Propulsion

NASA/JSC is implementing an advanced propulsion physics laboratory, informally known as "Eagleworks", to pursue propulsion technologies necessary to enable human exploration of the solar system over the next 50 years, and enabling interstellar spaceflight by the end of the century. This work directly supports the "Breakthrough Propulsion" objectives detailed in the NASA OCT TA02 In-space Propulsion Roadmap, and aligns with the #10 Top Technical Challenge identified in the report. Since the work being pursued by this laboratory is applied scientific research in the areas of the quantum vacuum, gravitation, nature of space-time, and other fundamental physical phenomenon, high fidelity testing facilities are needed.

originally posted by: Diablos

originally posted by: dragonridr
I look at the paper but looks like they are discussing low temperature decoherence. You know what's we call super conductivity.Fluctuations of local fields cause decoherence of quantum objects. Usually at high temperatures rhe thermal noises are much stronger than quantum fluctuations and undetectable unless the thermal effects are suppressed by certain techniqueslike spin echo.

Hmm, so if the paper is addressing superconductors, then what are the supposed implications? Could this lead to a new more comprehensive understanding of superconductivity? Is this idea, that you can gain momentum from the vacuum, plausible and well motivated? If yes, then wouldn't superconductivity become the primary tool for probing for quantum gravity effects? I'm sure there are a number of experiments one can do in this field that would yield much more information about the true nature of the quantum vacuum than using clunky and exorbitantly expensive accelerators.

If magnetic fields can be used to focus vacuum forces maybe but I have a feeling the effect will never produce any useful thrust. See the numbers we are talking are so small that we can't even tell if it's an error. What we have learned like in this paper we see them and thats what is Important. It confirms that indeed there is vacuum energy and helps explain things like superconductivity. Problem is for thrust It takes more energy than we see in gains. what we are finding is magnetic fields can effect vacuum energy. But more important it's like being able to movE the chess piece and seeing the board beneath it.

originally posted by: ImaFungi

EXACTLY !!