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cgreeleybsu

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- TL;DR Summary
- There is a lot of theoretical work and mathematical work on QI/QEI's however, there seems to be some, limited, experimental evidence that they do not exist. Is it probable I am being "led down the garden path" if I were to consider throwing out the idea of QI's given?

Hello all

I wasent sure if I should post this here or in GR. I was wondering anyone could help clear something up. In my research of negative energy, the idea of QI or QEI (Quantum Energy Inequalities) has come up, limits on negative energy. I have seen many papers showing mathematical descriptions (which I admittedly don't understand), and I never had a reason to question them (except the absence of physical observation) until I saw this paper entitled: "Experimental Concepts for Generating Negative Energy in the Laboratory" DOI: 10.1063/1.2169321 quote from the paper

I later found this paper by chance: Testing a Quantum Inequality with a Meta-analysis of Data for Squeezed Light DOI: 10.1007/s10701-019-00286-8

which claims to analyze several sets of experimental data to show QI's to be false.

This paper as well: "Static Negative Energies Near a Domain Wall" gr-qc/0205134

Davis & Puthof (first paper) also state:

(as well as QIs don’t hold for the Boulware vacuum state)Interestingly enough at the end of this paper it Roman states

– A New Paradigm for Local Quantum Field Theory arXiv:gr-qc/9805037v1 this paper has the most mentions of actual data I have found.

Roman also says:

Need to dig a little deeper to find out what that is (unless anyone here knows?)My question is, am I

A: The experimental evidence against (even though its just a couple of papers)

B: The lack of "pro" experimental evidence

C: They might not/do not apply to the Casimir Effect & Boulware vacuum state strangely as well as a number of spacetimes

vs. the pro reasons:

A: Lots of math and established work

B: There is a theory of an "interacting" QI

C: The "Static Negative Energies Near a Domain Wall" measures the Casimir effect which given the quasi agreement from some of the other sources, may not have QI apply hear and subtracts from the "against" evidence

Thank you

- Christopher A. Greeley

I wasent sure if I should post this here or in GR. I was wondering anyone could help clear something up. In my research of negative energy, the idea of QI or QEI (Quantum Energy Inequalities) has come up, limits on negative energy. I have seen many papers showing mathematical descriptions (which I admittedly don't understand), and I never had a reason to question them (except the absence of physical observation) until I saw this paper entitled: "Experimental Concepts for Generating Negative Energy in the Laboratory" DOI: 10.1063/1.2169321 quote from the paper

The Quantum Inequalities (QI) conjecture is an ad hoc extension of the Heisenberg Uncertainty Principle. They were essentially derived by a small group of curved spacetime quantum field theory specialists for the purpose of making the universe look rational and uninteresting (Pfenning, 1998; see also the excellent review by Ford and Roman, 2003)

I later found this paper by chance: Testing a Quantum Inequality with a Meta-analysis of Data for Squeezed Light DOI: 10.1007/s10701-019-00286-8

which claims to analyze several sets of experimental data to show QI's to be false.

This paper as well: "Static Negative Energies Near a Domain Wall" gr-qc/0205134

We show that a system of a domain wall coupled to a scalar field has static negative energydensity at certain distances from the domain wall. This system provides a simple, explicit exampleof violation of the averaged weak energy condition and the quantum inequalities by interactingquantum fields. Unlike idealized systems with boundary conditions or external background fields,this calculation is implemented precisely in renormalized quantum field theory with the energynecessary to support the background field included self-consistently.

Davis & Puthof (first paper) also state:

Which seems to be somewhat in agreement with "Some Thoughts on Energy Conditions and Wormholes" DOI 10.1142/9789812704030_0236This actually sounds quite reasonable on energy conservation grounds

until one finds out that the Casimir Effect (a squeezed vacuum state by virtue of its cavity boundary conditions) violates all three conditions

QIs don’t hold for the Casimir effect [48]. If the sampling time is chosen to be

small compared to the proper distance between the Casimir plates, then one does get

a QI bound [49]. Furthermore, the difference between the expectation value of the

energy density in an arbitrary state and in the Casimir vacuum state does satisfy a

QI bound [25, 50]. The physical interpretation of this “difference inequality” is that,

although it is possible to depress the energy density below the vacuum Casimir value,

it cannot be made arbitrarily negative for an arbitrarily long time. In the infinite

sampling time limit one finds that this difference of expectation values satisfies the

AWEC, even though the Casimir vacuum energy by itself does not"

(as well as QIs don’t hold for the Boulware vacuum state)Interestingly enough at the end of this paper it Roman states

And I did find this: "Quantum Energy Inequality for the Massive Ising Model" DOI 10.1103/PhysRevD.88.025019The QIs have been proven to date only for free fields. It would be rather surprising

if the inclusion of interactions drastically modified the current picture. Otherwise,

one might worry that this might lead to instabilities in the free field theory as well.

However, given the Olum-Graham results, further study offields is needed."interacting

On every paper I have seen for QI's, no experimental evidence is given except for the existence of the effects mentioned (Casimir, squeezed light, etc.)A quantum energy inequality is derived for the massive Ising model, giving a state-independent lower bound on suitable averages of the energy density, thewith nontrivial S-matrix. It is shown that the Ising model has one-particle states with locally negative energy densities and that the energy density operator is not additive with respect to the combination of one-particle states into multiparticle configurations.first quantum energy inequality to be established for an interacting quantum field theory

*search for the word "experiment" or "measure":*The Generally Covariant Locality Principle– A New Paradigm for Local Quantum Field Theory arXiv:gr-qc/9805037v1 this paper has the most mentions of actual data I have found.

Roman also says:

There is evidence that non-trivial spacetime-averaged QIs exist in 4D, although no simple analytic forms have yet been written down

Need to dig a little deeper to find out what that is (unless anyone here knows?)My question is, am I

*being*__probably__*"led down the garden path"*if I were to consider throwing out the idea of QI's given:A: The experimental evidence against (even though its just a couple of papers)

B: The lack of "pro" experimental evidence

C: They might not/do not apply to the Casimir Effect & Boulware vacuum state strangely as well as a number of spacetimes

vs. the pro reasons:

A: Lots of math and established work

B: There is a theory of an "interacting" QI

C: The "Static Negative Energies Near a Domain Wall" measures the Casimir effect which given the quasi agreement from some of the other sources, may not have QI apply hear and subtracts from the "against" evidence

Thank you

- Christopher A. Greeley

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