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DOE OSTI · 2373310

Dimension and Dimensional Reduction in Quantum Gravity

Carlip, Steven
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Abstract

If gravity is asymptotically safe, operators will exhibit anomalous scaling at the ultraviolet fixed point in a way that makes the theory effectively two-dimensional. A number of independent lines of evidence, based on different approaches to quantization, indicate a similar short-distance dimensional reduction. I will review the evidence for this behavior, emphasizing the physical question of what one means by “dimension” in a quantum spacetime, and will discuss possible mechanisms that could explain the universality of this phenomenon.

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Carlip, Steven. 2019-03-19. Dimension and Dimensional Reduction in Quantum Gravity. https://doi.org/10.3390/universe5030083

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