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Quantum Gravity Phenomenology, Lorentz Invariance and Discreteness

Fay Dowker·Joe Henson·Rafael D. Sorkin
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Abstract

Contrary to what is often stated, a fundamental spacetime discreteness need not contradict Lorentz invariance. A causal set's discreteness is in fact locally Lorentz invariant, and we recall the reasons why. For illustration, we introduce a phenomenological model of massive particles propagating in a Minkowski spacetime which arises from an underlying causal set. The particles undergo a Lorentz invariant diffusion in phase space, and we speculate on whether this could have any bearing on the origin of high energy cosmic rays.

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Fay Dowker, Joe Henson, Rafael D. Sorkin. 2004-07-12. Quantum Gravity Phenomenology, Lorentz Invariance and Discreteness. https://doi.org/10.1142/s0217732304015026

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