On Tuesday, August 27, 2019 at 7:53:26 AM UTC-6, Alan Grayson wrote: > > > > On Tuesday, August 27, 2019 at 3:17:41 AM UTC-6, Bruce wrote: >> >> On Tue, Aug 27, 2019 at 7:05 PM Alan Grayson <[email protected]> wrote: >> >>> On Tuesday, August 27, 2019 at 2:47:39 AM UTC-6, Alan Grayson wrote: >>>> >>>> On Tuesday, August 27, 2019 at 1:59:40 AM UTC-6, Bruce wrote: >>>>> >>>>> On Tue, Aug 27, 2019 at 5:39 PM Alan Grayson <[email protected]> >>>>> wrote: >>>>> >>>>>> On Tuesday, August 27, 2019 at 1:08:33 AM UTC-6, Bruce wrote: >>>>>>> >>>>>>> On Tue, Aug 27, 2019 at 4:57 PM Alan Grayson <[email protected]> >>>>>>> wrote: >>>>>>> >>>>>>>> >>>>>>>> But if virtual particles don't exist, if they're based on >>>>>>>> conceptual errors, what's the basis for claiming the vacuum is not a >>>>>>>> vacuum >>>>>>>> of nothingness? AG >>>>>>>> >>>>>>> >>>>>>> Virtual particles are a useful heuristic for evaluating a >>>>>>> perturbation series. The conceptual error is to reify the terms in this >>>>>>> series, particularly the virtual particles. Quantum foam, or the >>>>>>> picture of >>>>>>> virtual particles fluctuating in and out of existence, everywhere, and >>>>>>> all >>>>>>> the time. Is a major conceptual confusion. There are no such things as >>>>>>> quantum fluctuations in the requisite sense. Disconnected Feynman >>>>>>> diagrams >>>>>>> do not contribute to physical processes -- this is an elementary >>>>>>> text-book >>>>>>> result. >>>>>>> >>>>>>> Bruce >>>>>>> >>>>>> >>>>>> How then do you interpret the Casimir Effect? Isn't it used to >>>>>> experimentally establish the existence of virtual particles? AG >>>>>> >>>>> >>>>> The Casimir effect is perfectly well explained in terms of Van der >>>>> Waals type forces. Explanations in terms of virtual particles don't >>>>> really >>>>> work because virtual particles do not exert any force on anything -- >>>>> because they are not real!!!! >>>>> >>>>> Bruce >>>>> >>>> >>>> I see. What about the vacuum energy? What does it consist of if not >>>> virtual particles? AG >>>> >>> >>> Part of what I'm getting at is this; if the vacuum energy has anything >>> to do with the quantized EM field, the values 1/2*hbar *omega aren't >>> photons! So what is the form of energy in the vacuum? AG >>> >> >> Good question. Best answer to date is that it is Einstein's cosmological >> constant. Virtual particles can play no role because disconnected particle >> loops are necessarily of zero energy. >> >> Bruce >> > > Is there any experimental evidence that the vacuum energy is non zero? (I > assume dark energy is inferred from the accelerating expansion, but is not > considered part of the vacuum energy.) AG >
Slightly off topic for this thread. Do you believe the total net gravitational energy of the Cosmos is zero? 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/9df07d7b-1c4c-434a-a911-0e770d1266b4%40googlegroups.com.
