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You have found an elaborate way of calculating $2\pi \alpha/ \ln 2 \approx 0.0661658$. Here, $\alpha \approx 1/137$ represents the fine-structure constant. The points to note is that: A) Bekenstein's bound defines the maximum number of nats of information that can be contained in a spherical region as the circumference of that region divided by the reduced ...


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One can't take results like that too seriously at the scale at which an electron would apply. In particular, the classical general relativistic model, applied naively to a point mass electron would tell you that the electron has too large a charge and angular momentum to have a black hole horizon, and would instead be the exotic type of object called a ...


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The webpage you were looking at is run by H. D. Zeh. So if you want to find out what he's talking about the best way to find out is to look up some of his papers, such as: http://arxiv.org/abs/1012.4708. He describes decoherence in quantum gravity in Section 5 of the paper. The basic answer is as follows. The Wheeler-DeWitt equation is time-independent in ...


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In the particle-physics-oriented part of the theoretical physics community, it was becoming increasingly clear that the Dirac bracket is at most a complicated piece of formalism that isn't able to solve any real physical problems and make theories well-defined or finite or renormalizable etc. So the people who are playing with such tools applied to ...


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You know that SI units are arbitrary and not based on physical observations. I mean, kilogram, meter and second are arbitrary quantities based on what was reasonable in the 1700's. Their exact definition has been updated, but the amount their represent is arbitrary and bares no significance in nature. So there nothing special about any quantity defined in ...


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I think this basically sums up the program for what quantum gravity is. The modern viewpoint is that general relativity (and really just about any quantum field theory) is an effective field theory, and the full theory of quantum gravity must provide an ultraviolet completion. As explained in the Donoghue review suggested by bechira (another good review is ...



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