Fuzzy spacetime from a null-surface version of GR

• Main Authors: Frittelli, S, Kozameh, C. N, Newman, E. T, Rovelli, C, Tate, R. S
• Format: Journal Article
• Language: English
• Published: 29.03.1996
• Subjects: Physics - General Relativity and Quantum Cosmology
• DOI: 10.48550/arxiv.gr-qc/9603061

Class.Quant.Grav.14:A143-A154,1997 The null-surface formulation of general relativity -- recently introduced -- provides novel tools for describing the gravitational field, as well as a fresh physical way of viewing it. The new formulation provides ``local'' observables corresponding to the coordinates of points --- which constitute the spacetime manifold --- in a {\em geometrically defined chart\/}, as well as non-local observables corresponding to lightcone cuts and lightcones. In the quantum theory, the spacetime point observables become operators and the spacetime manifold itself becomes ``quantized'', or ``fuzzy''. This novel view may shed light on some of the interpretational problems of a quantum theory of gravity. Indeed, as we discuss briefly, the null-surface formulation of general relativity provides (local) geometrical quantities --- the spacetime point observables --- which are candidates for the long-sought physical operators of the quantum theory.