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Zero-point physics

by the blob inc
Tags: physics, zeropoint
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the blob inc
#2
Sep27-05, 03:48 PM
P: 31
For Those of you that dont know what zero-point physics is:

nasa would define it as:
"Zero Point Energy"
Zero Point Energy (ZPE), or vacuum fluctuation energy are terms used to describe the random electromagnetic oscillations that are left in a vacuum after all other energy has been removed. If you remove all the energy from a space, take out all the matter, all the heat, all the light... everything -- you will find that there is still some energy left. One way to explain this is from the uncertainty principle from quantum physics that implies that it is impossible to have an absolutely zero energy condition.
For light waves in space, the same condition holds. For every possible color of light, that includes the ones we can’t see, there is a non-zero amount of that light. Add up the energy for all those different frequencies of light and the amount of energy in a given space is enormous, even mind boggling, ranging from 10^36 to 10^70 Joules/m3.

In simplistic terms it has been said that there is enough energy in the volume the size of a coffee cup to boil away Earth’s oceans. - that’s one strong cup of coffee! For a while a lot of physics thought that concept was too hard to swallow. This vacuum energy is more widely accepted today.

What evidence shows that it exists?

First predicted in 1948, the vacuum energy has been linked to a number of experimental observations. Examples include the Casimir effect, Van der Waal forces, the Lamb-Retherford Shift, explanations of the Planck blackbody radiation spectrum, the stability of the ground state of the hydrogen atom from radiative collapse, and the effect of cavities to inhibit or enhance the spontaneous emission from excited atoms.

The Casimir Effect:
The most straight-forward evidence for vacuum energy is the Casimir effect. Get two metal plates close enough together and this vacuum energy will push them together. This is because the plates block out the light waves that are too big to fit between the plates. Eventually you have more waves bouncing on the outside than from the inside, the plates will get pushed together from this difference in light pressure. This effect has been experimentally demonstrated.

Can we tap into this energy?

It is doubtful that this can be tapped, and if it could be tapped, it is unknown what the secondary consequences would be. Remember that this is our lowest energy point. To get energy out, you presumably need to be at a lower energy state. Theoretical methods have been suggested to take advantage of the Casimir effect to extract energy (let the plates collapse and do work in the process) since the region inside the Casimir cavity can be interpreted as being at a lower energy state. Such concepts are only at the point of theoretical exercises at this point.

With such large amount of energy, why is it so hard to notice?

Imagine, for example, if you lived on a large plateau, so large that you didn’t know you were 1000 ft up. From your point of view, your ground is at zero height. As long as your not near the edge of your 1000 ft plateau, you won’t fall off, and you will never know that your zero is really 1000. It’s kind of the same way with this vacuum energy. It is essentially our zero reference point.

What about propulsion implications?

The vacuum fluctuations have also been theorized by Haisch, Rueda, and Puthoff to cause gravity and inertia. Those particular gravity theories are still up for debate. Even if the theories are correct, in their present form they do not provide a means to use electromagnetic means to induce propulsive forces. It has also been suggested by Millis that any asymmetric interactions with the vacuum energy might provide a propulsion effect.

this is straight from nasa:
http://www.nasa.gov/centers/glenn/re.../possible.html


Wikipedia the online enclopidia would define it as:
In a quantum mechanical system such as the particle in a box or the quantum harmonic oscillator, the lowest possible energy is called the zero-point energy. According to classical physics, the kinetic energy of a particle in a box or the kinetic energy of the harmonic oscillator may be zero if the velocity is zero. Quantum mechanics with its uncertainty principle implies that if the velocity is measured with certainty to be exactly zero, the uncertainty of the position must be infinite. This either violates the condition that the particle remain in the box, or it brings a new potential energy in the case of the harmonic oscillator. To avoid this paradox, quantum mechanics dictates that the minimal velocity is never equal to zero, and hence the minimal energy is never equal to zero.

A few formulae
A particle in a box is defined by the potential energy

V(x) = 0 for
which is defined to be infinite for . The wave function with the minimal energy eigenvalue is then

ψ(x) = Csin(πx / l)
where C is an important normalization constant. The (zero-point) energy of this wave function is pure kinetic and equal to


which is non-zero. Similarly, the zero-point energy of the quantum harmonic oscillator with the frequency ω is equal to


Both of these simplest cases have a useful generalization to the case of quantum field theory. Quantum field theory - such as Quantum Electrodynamics - may be regarded as a collection of infinitely many harmonic oscillators, and quantum mechanics therefore predicts a nonzero vacuum energy. Although the absolute value of the vacuum energy is partly a matter of convention, the difference between the vacuum energy of various configurations has a physical meaning.


Existence
Does electromagnetic zero-point energy exist, and if so, are there any practical applications and does it have any connection with dark energy? The theoretical basis for electromagnetic zero-point energy is clear. According to Sciama (1991):

"Even in its ground state, a quantum system possesses fluctuations and an associated zero-point energy, since otherwise the uncertainty principle would be violated. In particular the vacuum state of a quantum field has these properties. For example, the electric and magnetic fields in the electromagnetic vacuum are fluctuating quantities."
The Casimir effect is an example of a one-loop effect in quantum electrodynamics that can be simply explained by the zero-point energy.

[edit]
History
The concept of zero-point energy originated with Max Planck in 1911. The average energy of a harmonic oscillator in this hypothesis is (where h is Planck's constant and ν is frequency):


At the same time Einstein and Hopf (1910) and Einstein and Stern (1913) were also studying the properties of zero-point energy. Shortly thereafter Nernst (1916) proposed that empty space was filled with zero-point electromagnetic radiation. Then in 1925 the existence of zero-point energy was shown to be “required by quantum mechanics, as a direct consequence of Heisenberg's uncertainty principle” (Sciama 1991). As any textbook on quantum optics will show (e.g. Loudon 1983), the way to quantize the electromagnetic field is to associate each mode of the field with a harmonic oscillator with the result that the minimum energy per mode of the electromagnetic quantum vacuum is hν / 2 .

[edit]
Problems and answers
Zero-point energy shares a problem with the Dirac sea: both are potentially infinite. In the case of zero-point energy, there are reasons for believing that a cutoff does exist in the zero-point spectrum corresponding to the Planck scale. Even this results in an enormous amount of zero-point energy whose existence is assumed to be negated (in spite of the unmistakable mandate of the Heisenberg uncertainty principle) by the claim that the mass equivalent of the energy should gravitate, resulting in an absurdly large cosmological constant, contrary to observations. Matters are not quite so straightforward.

In response to the question “Do Zero-Point Fluctuations Produce a Gravitational Field?” Sciama (1991) writes:

"We now wish to comment on the unsolved problem of the relation between zero-point fluctuations and gravitation. If we ascribe an energy hν / 2 to each mode of the vacuum radiation field, then the total energy of the vacuum is infinite. It would clearly be inconsistent with the original assumption of a background Minkowski space-time to suppose that this energy produces gravitation in a manner controlled by Einstein’s field equations of general relativity. It is also clear that the space-time of the real world approximates closely to the Minkowski state, at least on macroscopic scales. It thus appears that we must regularize the zero-point energy of the vacuum by subtracting it out according to some systematic prescription. At the same time, we would expect zero-point energy differences to gravitate. For example, the (negative) Casimir energy between two plane-parallel perfect conductors would be expected to gravitate; otherwise, the relativistic relation between a measured energy and gravitation would be lost."
It is precisely localizable differences in the zero-point energy that may prove to be of some practical use and that may be the basis of dark energy phenomena. Moreover it has also been found that asymmetries in the zero-point field that appear upon acceleration may be associated with certain properties of inertia, gravitation and the principle of equivalence Haisch, Rueda and Puthoff (1994); Rueda and Haisch (1998); Rueda and Haisch (2005).

[edit]
Properties
Lastly, insights may be offered on certain quantum properties (Compton wavelength, de Broglie wavelength, spin) and on mass-energy equivalence (E=mc2) if it proves to be the case that zero-point fluctuations interact with matter in a phenomenon identified by Erwin Schrödinger known as zitterbewegung (Haisch and Rueda 2000; Haisch, Rueda and Dobyns 2001; Nickisch and Mollere 2002).

As intriguing as these latter possibilities are, the first order of business is to unambiguously detect and measure zero-point energy. While a Casimir experiment such as that of Forward (1984) can in principle measure energy that may be attributed to the existence of real zero-point energy, there are alternative explanations involving source-source quantum interactions in place of real zero-point energy (see Milonni 1994). To move beyond this ambiguity of interpretation experiments that will test for the reality of measurable zero-point energy will need to be devised.

so if any one has more info on this new branch of physics(as of 2000), i need help.
Deckers
#3
Sep28-05, 02:05 AM
P: 16
That is not considered Conventional Physics I think. It reminds me of Quantum Mechanics, the total energy in any mass is large we're told. But extraction without destruction is implicit in your desire to produce "Zero Point Energy".

There's some stuff online which generally leads you to UFO's and such. But while questionable, it's interesting anyway.The only energy dependant particle mechanics normal people see past college is in SSC's. This stuff raises questions about inter-relationial functions of subatomic particles that aren't openly discussed.

Wouldn't it be nice to have a TOE suddenly printed in the paper tomorrow? Something like " We finally have it. Field energy A does . . . Field energy B does . . . and what we have discovered is that Field energy D can power your home and car with twenty cents worth of hardware from the Radioshack downtown."

ZapperZ
#4
Sep28-05, 04:56 AM
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Zero-point physics

Quote Quote by Deckers
That is not considered Conventional Physics I think. It reminds me of Quantum Mechanics, the total energy in any mass is large we're told. But extraction without destruction is implicit in your desire to produce "Zero Point Energy".
Not considered conventional physics? Since when? And since when do YOU know what conventional physics is? Have you checked how many papers on Casimir effects have appeared in Phys. Rev. Lett.? Or maybe you only only read the CRC handbook? And considering that Eric Cornell and his group just published a remarkable paper on the measurement of such a force on a single atom using BEC condensates, what you are saying is outrageously wrong!

http://focus.aps.org/story/v16/st8

Zz.
Deckers
#5
Sep28-05, 09:32 AM
P: 16
Zapper;
You are an insultive person, I suspect you don't wish to add a reply but prefer to insult me instead. That is inconsiderate to the poster, and adds nothing to the thread.

Zero Point Energy has never been publicly proven to function viably. The hypothesis exists that it may but "energy for nothing" is the general perception.

Who would care if they got booted from your condescending and fruitless "enjoyable discussion"? I'm not looking for another degree, but maybe you're up to bat.
ZapperZ
#6
Sep28-05, 09:41 AM
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Quote Quote by Deckers
Zapper;
You are an insultive person, I suspect you don't wish to add a reply but prefer to insult me instead. That is inconsiderate to the poster, and adds nothing to the thread.

Zero Point Energy has never been publicly proven to function viably. The hypothesis exists that it may but "energy for nothing" is the general perception.

Who would care if they got booted from your condescending and fruitless "enjoyable discussion"? I'm not looking for another degree, but maybe you're up to bat.
Please check what you have posted and then consider if you have added anything to the thread rather than making erroneous statements. I really don't care if you feel "insulted" since you, in turn, do not care if you are making an accurate statement. The CONTENT of your postings so far have been either outright mistakes, or filled with outrageous misunderstanding. The fact that you do not even bother checking the validity of what you are saying is ALSO INSULTING to those of us who work and respect this field of study. Have you ever considered THAT?

And while we are talking about ADDING to the thread, I have included an explicit citation to back up on what I have said regarding the validity of this phenomenon. You haven't. And if you have bothered to do a search on this topic even just here in this forum, you would have seen SEVERAL discussions already on this very subject including a number of references from respected journals. So how in the world can anyone claim that such a thing is (i) outside conventional physics and (ii) that it hasn't been verified? This is exactly MY point in accusing you of having no knowledge of what you are babbling.

Zz.
Doc Al
#7
Sep28-05, 09:44 AM
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Quote Quote by Deckers
Zero Point Energy has never been publicly proven to function viably. The hypothesis exists that it may but "energy for nothing" is the general perception.
Don't confuse the "general perception" (as promoted by cranks and crackpots) with the real science.
Manchot
#8
Sep28-05, 10:53 AM
P: 728
Quote Quote by Doc Al
Don't confuse the "general perception" (as promoted by cranks and crackpots) with the real science.
Exactly. I think that Deckers is thinking of the sci-fi version of ZPE (think Stargate SG-1/Atlantis), not the sci-fa version.
Deckers
#9
Sep28-05, 11:04 AM
P: 16
In the oil field we have a concept called "Jerking Somebodies Chain". It means if you are hurtful and insultive enough to someone, they will answer your question. It works sometimes I guess.

The roots of Zero Point Energy are in historical German {?Nazi} Research, but so are guided missiles and jet engines.

The question was "has anybody heard anything new in the field of Zero Point Energy" My answer was no, and the net is tougher to navigate with little but a title to go on.

A Google search reveals 20,300,000 hits for Zero Point Energy . Of which this thread will now constitute a small portion now.

I only replied to show support for the suposition, not to degrade it.
I'm sure that will be of benefit to people.
ZapperZ
#10
Sep28-05, 11:35 AM
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Quote Quote by Deckers
In the oil field we have a concept called "Jerking Somebodies Chain". It means if you are hurtful and insultive enough to someone, they will answer your question. It works sometimes I guess.

The roots of Zero Point Energy are in historical German {?Nazi} Research, but so are guided missiles and jet engines.

The question was "has anybody heard anything new in the field of Zero Point Energy" My answer was no, and the net is tougher to navigate with little but a title to go on.

A Google search reveals 20,300,000 hits for Zero Point Energy . Of which this thread will now constitute a small portion now.

I only replied to show support for the suposition, not to degrade it.
I'm sure that will be of benefit to people.
How did it "benefit to people" when you obviously missed the reference I gave? How "new" do you want it to be? 3 hours ago? The Eric Cornell paper was published in PRL just LAST WEEK! That isn't new enough?

And note that your response to the original posting included a claim that this isn't part of "conventional phyiscs" (your words, not mine) and unverified! This ignores completely the large body of work done on Casimir effect, the same way you ignored a complete field of study in physics (solid state physics) when you decided to tackle conductivity. Casimir effect IS and HAS been verified in many different ways. And as Doc Al has pointed out, "zero point energy" came out of legitimate physics that has been bastardized by many quacks. Do not confuse one with the other.

A google search? How about you go to the Physical Review website and do a search THERE?! But this also highlights what I believe is what you are doing - that your responses are based on the info you gathered off the web, rather than an intimate knowledge of that subject matter based on a formal study. Aren't you the least bit concern of the depth of your understanding of something if all you did was read it off some website? There is nothing wrong with doing a websearch. There is, however, a lot of things wrong when you act like an expert when all you did was read things off the web.

In case you haven't noticed, PF is NOT like any other open forums where you can make any blatant statement as you wish without bothering to check the validity of your statements. There are enough people with significant expertise in many areas of physics that you WILL be smacked around if you make ignorant statements the way you did.

Zz.
pervect
#11
Sep28-05, 02:06 PM
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Quote Quote by ZapperZ
Not considered conventional physics? Since when? And since when do YOU know what conventional physics is? Have you checked how many papers on Casimir effects have appeared in Phys. Rev. Lett.? Or maybe you only only read the CRC handbook? And considering that Eric Cornell and his group just published a remarkable paper on the measurement of such a force on a single atom using BEC condensates, what you are saying is outrageously wrong!

http://focus.aps.org/story/v16/st8

Zz.
I'm not sure what all the flaming is about, however, I would say that "Casimir force" is repectably mainstream, while Puthoff's theories are on the fringe (Puthoff does have some papers published on the topic in PRL, Puthoff, HE, “Source of Vacuum Electromagnetic Zero-Point Energy”, Physical Review A, for instance, but I would still call his theories fringe rather than mainstream).

There are other people out there talking about ZPE who are downright cranks, like Tom Bearden and his book "Energy from the Vacuum".
ZapperZ
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Sep28-05, 02:23 PM
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Quote Quote by pervect
I'm not sure what all the flaming is about, however, I would say that "Casimir force" is repectably mainstream, while Puthoff's theories are on the fringe (Puthoff does have some papers published on the topic in PRL, Puthoff, HE, “Source of Vacuum Electromagnetic Zero-Point Energy”, Physical Review A, for instance, but I would still call his theories fringe rather than mainstream).

There are other people out there talking about ZPE who are downright cranks, like Tom Bearden and his book "Energy from the Vacuum".
I certainly agree. I cringe when we get people claiming you can get "useable" energy out of such things, sometime even an endless supply of it. One only needs to look at how difficult it is to make a clear detection of Casimir effect.

But certainly, the consequences of zero-point energy, such as in the form of Casimir effect AND the deBoer effect in Noble gasses are well-known and is well within "conventional physics". We can't control what quacks do with it, the same way we can't control when they bastardize SR and QM.

Zz.


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