An improved derivation of minimum information quantum gravity
Pierre A. Mandrin
备注：
21 pages. v2: more details in the proof of the space-time structure; text improved; some parts transfered to appendix, added by summaries of some previously published concepts, a few formulations more comprehensive. Prepared for submission to Annals of Physics. v3: Minor revision (boundary law: "non-thin-layers", clean notation; Legendre transf.: tetrad bath; proof local trivializ. on subsystems)
Minimum information quantum gravity (MIQG) is a theory of quantum gravity which requires no explicit microscopic quantum structure. In this article, it is shown that the MIQG action can be derived using a more elegant and straight-forward method than in the first existence proof. The required assumptions are dramatically reduced. In particular, former assumptions referring to the existence of quantum boxes, the exact differential of the entropy variation and the role of the boundary can be omitted. Moreover, the open problem of the quantum occupation number per box is solved. Thus, the arguments in favour of MIQG become even more stringent. The remaining assumptions are 1. the principle of optimisation of the resulting per imposed degrees of freedom, 2. abstract quantum number conservation, 3. the validity of the laws of thermodynamics, 4. identification of a macroscopic parameterisation with space-time and 5. unspecific interactions. Although the requirements are reduced, all former results remain valid. In particular, all well established physics as special cases (Quantum Field Theory, QFT, and General Relativity, GR) follow and all measurable quantities may be computed.
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