On Sunday, April 19, 2020 at 4:50:52 PM UTC-5, Alan Grayson wrote: > > > > On Sunday, April 19, 2020 at 2:37:28 PM UTC-6, Lawrence Crowell wrote: >> >> Sure the Casimir effect involves QED. The virtual photons are in a sense >> a set of gauge redundancies that can be removed, though one need the moduli >> from these redundancies. This still defines a form of quantum topological >> number. >> >> LC >> > > You refer to QED, but aren't wan der Waal forces non quantum? AG >
Van der Waal force is just a dipole-dipole interaction, such as what happens with water on the fluid surface. This can well enough be quantized. LC > >> On Sunday, April 19, 2020 at 11:30:51 AM UTC-5, Alan Grayson wrote: >>> >>> >>> >>> On Sunday, April 19, 2020 at 9:11:46 AM UTC-6, Lawrence Crowell wrote: >>>> >>>> The only thing that is measured is a difference in energy, and the >>>> modes between two parallel plates are different from those outside. So the >>>> difference in energy results in this slight pressure. >>>> >>>> LC >>>> >>> >>> From Wiki, below. Apparently there's an interpretation of the Casimir >>> effect which doesn't depend on vacuum energy, which, as I recall, is >>> Bruce's position on this issue. If no vacuum energy, then the claim that >>> photons and other elementary particles arose from the vacuum in the very >>> early universe is on dubious grounds. AG >>> >>> Relativistic van der Waals force[edit >>> <https://en.wikipedia.org/w/index.php?title=Casimir_effect&action=edit§ion=5> >>> ] >>> >>> Alternatively, a 2005 paper by Robert Jaffe >>> <https://en.wikipedia.org/wiki/Robert_Jaffe> of MIT states that >>> "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 approaching infinity limit," and that "The >>> Casimir force is simply the (relativistic, retarded >>> <https://en.wikipedia.org/wiki/Retarded_potential>) van der Waals force >>> between the metal plates."[17] >>> <https://en.wikipedia.org/wiki/Casimir_effect#cite_note-17> Casimir and >>> Polder's original paper used this method to derive the Casimir-Polder >>> force. In 1978, Schwinger, DeRadd, and Milton published a similar >>> derivation for the Casimir Effect between two parallel plates.[18] >>> <https://en.wikipedia.org/wiki/Casimir_effect#cite_note-18> In fact, >>> the description in terms of van der Waals forces is the only correct >>> description from the fundamental microscopic perspective,[19] >>> <https://en.wikipedia.org/wiki/Casimir_effect#cite_note-19>[20] >>> <https://en.wikipedia.org/wiki/Casimir_effect#cite_note-20> while other >>> descriptions of Casimir force are merely effective macroscopic descriptions. >>> >>>> >>>> On Saturday, April 18, 2020 at 10:40:45 PM UTC-5, Alan Grayson wrote: >>>>> >>>>> Does the Casimir effect establish that the vacuum has intrinsic >>>>> energy, and if so, what is its form? TIA, AG >>>>> >>>> -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/2ea86018-eff3-4d38-85bd-6d7226145975%40googlegroups.com.
