Note on possible emergence time of Newtonian gravity

Abstract

If gravity were an emergent phenomenon, some relativistic as well as non-relativistic speculations claim it is, then a certain emergence time scale τ ? would characterize it. We argue that the available experimental evidences have poor time resolution regarding how immediate the creation of Newton field of accelerated mass sources is. Although the concrete theoretical model of gravity's 'laziness' is missing, the concept and the scale τ ? ∼ 1ms, rooted in an extrapolation of spontaneous wave function collapse theory, might be tested directly in reachable experiments. tel/fax: +36-302956469/-13959151, e-mail: diosi.lajos@wigner.mta.huPhysicists have always been speculating that gravity may emerge from a structure of deeper level. Gravity has been resisting to relativistic quantum field theories despite their robust success all over the past fifty-sixty years. If gravity itself is not a relativistic quantized field, it might be induced by them. According to Sakharov [1], the Casimir energy of quantized matter fields yields elastic forces on the background space-time, resulting in similar dynamics to Einstein's general relativity. This approach, its variants and refinements (cf., e.g., [2,3]) represent the main stream of 'emergent gravity' investigations. Alternative concepts [4-6] relate Einstein's theory to thermodynamics and derive the gravitational force from the entropy. Other speculations postpone the relativistic aspects, abandon quantum field theory, but assume an intrinsic relationship between Newtonian (i.e., non-relativistic) gravity and quantum mechanics [7][8][9][10][11][12][13]. Some advocate phenomenological mechanisms for the emergence of the Newton interaction [11,14,15].Our note restricts itself for emergence of the Newtonian, non-relativistic gravity. If this emergence is real at all, it must be characterized by a certain emergence time τ ? and the value of τ ? is expected to be longer than the typical time-scales of relativistic emergence. It could depend on the wave length but we further simplify our assumption as to look for a single time scale τ ? . We mean that the gravitational field of an accelerated mass source shall not immediately follow the Newton law but with a delay of about τ ? . Although the concrete model of emergence is missing, the option has been discussed recently [15] as a plausible consequence of the gravityrelated spontaneous wave function collapse theory [8,10]. The heuristic discussion concluded to the existence of a characteristic emergence time τ ? ∼ 1ms.As we said, our proposal is purposely non-relativistic but its relationship to the Einstein theory must be stated. A slight laziness, like τ ? ∼ 1ms, in creating gravity would not invalidate the Einstein theory for the large scale dynamics of space-time. The only available experimental (indirect) evidence of gravitational waves confirms the radiation of the Hulse-Taylor binary pulsar at period 7.75h [16], no way would they be influenced by our proposal.Further relativistic predictions of the Einstein theory are light d...

Gravity-related spontaneous wave function collapse in bulk matter

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Equation and test of possible delay time of Newton force

“…As we argued in [1], no experimental evidence exists against our scale τ G ∼ 1 ms of the delay grounded in quantum foundational speculations [3,4]. The proposed modification of the Newton law is not a necessary one.…”

“…Recently, we have discussed a slight non-relativistic modification of the Newton law of universal gravitation [1]. Alternative to other suggestions that modified the 1/r shape of the potential [2], the new proposal relaxes the synchronous emergence of the 1/r potential.…”

Gravity-Related Wave Function Collapse

“…Ref. [22] has tried to reconciliate the existence of a 1ms emergence time with state-of-the-art Newtonian gravity. The available experimental, both astronomic and laboratory, evidences have poor time-resolution, perhaps not better than 1ms.…”