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http://arxiv.org/hep-th/0503158
The Casimir Effect and the Quantum Vacuum
R. L. Jaffe
9 pages, 3 figures
"In discussions of the cosmological constant, the Casimir effect is often invoked as decisive evidence that the zero point energies of quantum fields are 'real'. On the contrary, Casimir effects can be formulated and Casimir forces can be computed without reference to zero point energies. They are relativistic, quantum forces between charges and currents. The Casimir force (per unit area) between parallel plates vanishes as \alpha, the fine structure constant, goes to zero, and the standard result, which appears to be independent of \alpha, corresponds to the \alpha\to\infty limit."
Jaffe is a senior respected guy at MIT. Not a nut.
He debunks the usual presumption that the Casimir effect has something to do with
the "dark energy" or "vacuum energy" of cosmology.
I like it that he goes against my preconceptions a little. I think it is a really well-written paper and could have Quantum Gravity repercussions.
It isn't yet sure that dark energy is real. after all. Here is another quote from jaffe:
---quote---
As evidence of the “reality” of the quantum fluctuations of fields in the vacuum, theorists often point to the Casimir effect [6]. For example, Weinberg in his introduction to the cosmological constant problem, writes[5],
“Perhaps surprisingly, it was along time before particle physicists began seriously to worry about [quantum zero point fluctuation contributions to ?] despite the demonstration in the Casimir effect of the reality of zero-point energies.”
More recent examples can be found in the widely read reviews by Carroll[7],
“ ... And the vacuum fluctuations themselves are very real, as evidenced by the Casimir effect.”
and by Sahni and Starobinsky [8],[9]
“The existence of zero-point vacuum fluctuations has been spectacularly demonstrated by the Casimir effect.”
---end quote---
it looks like jaffe is nailing prominent figures like Steven Weinberg and
Sean Carroll
---quote---
I have presented an argument that the experimental confirmation of the Casimir effect does not establish the reality of zero point fluctuations. Casimir forces can be calculated without reference to the vacuum and, like any other dynamical effect in QED, vanish as ? ?0. ...
The deeper question remains: Do the zero point energies of quantum fields contribute to the energy density of the vacuum and, mutatis mutandis, to the cosmological constant?
Certainly there is no experimental evidence for the “reality” of zero point energies in quantum field theory (without gravity). Perhaps there is a consistent formulation of relativistic quantum mechanics in which zero point energies never appear. I doubt it. ... Still, no known phenomenon, including the Casimir effect, demonstrates that zero point energies are “real”.
---endquote---
The Casimir Effect and the Quantum Vacuum
R. L. Jaffe
9 pages, 3 figures
"In discussions of the cosmological constant, the Casimir effect is often invoked as decisive evidence that the zero point energies of quantum fields are 'real'. On the contrary, Casimir effects can be formulated and Casimir forces can be computed without reference to zero point energies. They are relativistic, quantum forces between charges and currents. The Casimir force (per unit area) between parallel plates vanishes as \alpha, the fine structure constant, goes to zero, and the standard result, which appears to be independent of \alpha, corresponds to the \alpha\to\infty limit."
Jaffe is a senior respected guy at MIT. Not a nut.
He debunks the usual presumption that the Casimir effect has something to do with
the "dark energy" or "vacuum energy" of cosmology.
I like it that he goes against my preconceptions a little. I think it is a really well-written paper and could have Quantum Gravity repercussions.
It isn't yet sure that dark energy is real. after all. Here is another quote from jaffe:
---quote---
As evidence of the “reality” of the quantum fluctuations of fields in the vacuum, theorists often point to the Casimir effect [6]. For example, Weinberg in his introduction to the cosmological constant problem, writes[5],
“Perhaps surprisingly, it was along time before particle physicists began seriously to worry about [quantum zero point fluctuation contributions to ?] despite the demonstration in the Casimir effect of the reality of zero-point energies.”
More recent examples can be found in the widely read reviews by Carroll[7],
“ ... And the vacuum fluctuations themselves are very real, as evidenced by the Casimir effect.”
and by Sahni and Starobinsky [8],[9]
“The existence of zero-point vacuum fluctuations has been spectacularly demonstrated by the Casimir effect.”
---end quote---
it looks like jaffe is nailing prominent figures like Steven Weinberg and
Sean Carroll
---quote---
I have presented an argument that the experimental confirmation of the Casimir effect does not establish the reality of zero point fluctuations. Casimir forces can be calculated without reference to the vacuum and, like any other dynamical effect in QED, vanish as ? ?0. ...
The deeper question remains: Do the zero point energies of quantum fields contribute to the energy density of the vacuum and, mutatis mutandis, to the cosmological constant?
Certainly there is no experimental evidence for the “reality” of zero point energies in quantum field theory (without gravity). Perhaps there is a consistent formulation of relativistic quantum mechanics in which zero point energies never appear. I doubt it. ... Still, no known phenomenon, including the Casimir effect, demonstrates that zero point energies are “real”.
---endquote---
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