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: Yalescientific.orgAlthough gravity never reaches zero, it gets close.
A vacuum can be viewed not as empty space but as the combination of all zero-point fields. In QFT this combination of fields is called the vacuum state, its associated zero-point energy is called the vacuum energy and the average expectation value of zero-point energy is called the vacuum expectation value (VEV) also called its condensate. The term zero-point field(ZPF) is sometimes used when referring to a specific vacuum field. The QED vacuum is a part of the vacuum state which specifically deals with quantum electrodynamics (e.g. electromagnetic interactions between photons, electrons and the vacuum) and the QCD vacuumdeals with quantum chromodynamics(e.g. color charge interactions between quarks, gluons and the vacuum). Recent experiments advocate the idea that particles themselves can be thought of as excited states of the underlying quantum vacuum, and that all properties of matter are merely vacuum fluctuations arising from interactions of the zero-point field.
The idea that "empty" space can have an intrinsic energy associated to it, and that there is no such thing as a "true vacuum" is seemingly unintuitive. For many practical calculations (especially in QED) zero-point energy is dismissed by fiat in the mathematical model as a constant that may be canceled or as a term that has no physical effect. Such treatment causes problems however, as in Einstein's theory of general relativity the absolute energy value of space is not arbitrary and gives rise to the cosmological constant. Furthermore, many physical effects attributed to zero-point energy have been experimentally verified, such as spontaneous emission, Casimir force, Lamb shift, magnetic moment of the electron and Delbrück scattering,these effects are usually called "radiative corrections". In more complex nonlinear theories (e.g. QCD) zero-point energy can give rise to a variety of complex phenomena such as multiple stable states, symmetry breaking, chaos and emergence.Physics currently lacks a full theoretical model for understanding zero-point energy, in particular the discrepancy between theorized and observed vacuum energy is a source of major contention. Physicists John Wheelerand Richard Feynman calculated the zero-point radiation of the QED vacuum to be an order of magnitude greater than nuclear energy, with one teacup containing enough to boil all the world's oceans while experimental evidence from both the expansion of the universe and the Casimir effect show any such force to be exceptionally weak. This discrepancy is known as the cosmological constant problem (or vacuum catastrophe) and is one of the greatest unsolved mysteries in physics.Many physicists believe that "the vacuum holds the key to a full understanding of nature"  and that studying it is critical in the search for the theory of everything. Active areas of research include the effects of virtual particles, quantum entanglement,the difference (if any) between inertial and gravitational mass, variation in the speed of light, a reason for the observed value of the cosmological constant and the nature of dark energy.The concept of zero-point energy was developed by Max Planck in Germany in 1911 as a corrective term added to a zero-grounded formula developed in his original quantum theory in 1900.
: AlanThe search for a zero-field point is merely the search for the point at which the frequency of that clock, as observed from any other point, is at its maximum.
The mass of the source clock is irrelevant.
My model predicts that the clock in the denser location will run faster.
.........My model predicts that the clock in the denser location will run faster.
"No - the mass 'value' of the clock is irrelevant, but the fact of the mass itself is highly relevant because if there were no mass present at that location in space, then the pe=mgh would just be pe=gh, or more conventionally, the gravitational field strength (vacuum energy) would be g(r)=GM/r^2, (or whatever the equivalent equation for multiple fields is)"
Another interesting question might be, should you be able to measure a rotation in your universe?
But the clock doesn't sense M, only the gravitational field associated with it, so it makes no difference whether you increase M or reduce x.
Unless you are proposing an entirely new force that looks like gravity, works backwards, only affects clocks, and has never been detected previously.
.That's pretty radical, especially as the red shift of the solar spectrum (large M compared with Mearth) is exactly what you would calculate without it.
As for the addition and subtraction of potential energy in the absence of rest mass, I think you will find this well covered by the explanation of gravitational lensing.
It's also interesting that the PR result is exactly what you expect from a calculation of exchange between potential and kinetic energy for a photon.
On a matter of linguistics, "conventional physics" doesn't "believe" anything. We make hypotheses and test them. Fact is that clocks run slower at a lower gravitational potential.
The job of theoretical physics is to explain and extrapolate observation, not to dismiss it as belief.
Now we have an observation and a theory which so far has predicted the next result,
and you want to replace it with a theory that predicts exactly the opposite.
Quote from: jeffreyH on 19/04/2017 12:36:06The gravity inside a hollow sphere only cancels completely at the centre of mass. If the thickness of your shell equalled the diameter of Jupiter then the closer to an interior surface the greater the force.https://physics.stackexchange.com/questions/43626/is-spacetime-flat-inside-a-spherical-shell
The gravity inside a hollow sphere only cancels completely at the centre of mass. If the thickness of your shell equalled the diameter of Jupiter then the closer to an interior surface the greater the force.
QuoteBut the clock doesn't sense M, only the gravitational field associated with it, so it makes no difference whether you increase M or reduce x.What on earth are you on about?A clock is observed to undergo a change in frequency of electron transitions due to changes in the gravitational field. The gravitational field is due to M.Change the value of M and the clock will be experiencing a changed gravitational field.