Is it time to rethink quantum gravity?

• URL: http://arxiv.org/abs/2310.12221v1
• Date: Wed, 18 Oct 2023 18:01:05 GMT
• Title: Is it time to rethink quantum gravity?
• Authors: Jonathan Oppenheim
• Abstract summary: It's widely believed that gravity should have a quantum nature like every other force. I discuss arguments for this proposition, but ultimately conclude that we must turn to experiment to guide us.
• Score: 0.0
• License: http://creativecommons.org/licenses/by-sa/4.0/
• Abstract: Although it's widely believed that gravity should have a quantum nature like every other force, the conceptual obstacles to constructing a quantum theory of gravity compel us to explore other perspectives. Gravity is not like any other force. It alone defines a universal space-time geometry, upon which quantum fields evolve. We feel gravity because matter causes space-time to bend. Time flows at unequal rates at different locations. The rate at which time flows, and the causal structure it provides, may be required to have a classical description in order for quantum theory to be well-formulated. I discuss arguments for this proposition, but ultimately conclude that we must turn to experiment to guide us.

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