Have We Lost Spacetime on the Way? Narrowing the Gap Between General Relativity and Quantum Gravity (original) (raw)
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Against the disappearance of spacetime in quantum gravity
Synthese, 2019
This paper argues against the proposal to draw from current research into a physical theory of quantum gravity the ontological conclusion that spacetime or spatiotemporal relations are not fundamental. As things stand, the status of this proposal is like the one of all the other claims about radical changes in ontology that were made during the development of quantum mechanics and quantum field theory. However, none of these claims held up to scrutiny as a consequence of the physics once the theory was established and a serious discussion about its ontology had begun. Furthermore, the paper argues that if spacetime is to be recovered through a functionalist procedure in a theory that admits no fundamental spacetime, standard functionalism cannot serve as a model: all the known functional definitions are definitions in terms of a causal role for the motion of physical objects and hence presuppose spatiotemporal relations.
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1999
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Lecture Notes in Physics, 1982
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A New Look at Space-Time Towards a Unified Quantum Geometry
Abstract The fundamental relation between space and time is motion expressed as the ratio of space over time for motion in space and the ratio of time over space for motion in time. This indicates that space and time are co-existent reciprocal aspects of motion. While inseparable and interdependent both space and time have distinct geometric properties. There are two fundamental quantum holographic interference patterns which most closely exemplify these structural properties. These are separately identified and defined consistent with the space-time reciprocal relationship. Quantum time potentials and space time networks are defined. The first network consists of two interacting quantum time potentials forming a space-time network whereby space is an emergent feature; there being an inverse structure with inverse properties. The phenomenon of mass and force are emergent features from the various permutations of interconnections between nodes within this space-time network. The resulting structure implies the existence of a coordinate system where each node represents coordinates defined by the rays from each pole. The coordinates form an information field and indicate that space and time ARE information, The connections between the nodes are determined by pre-mathematical connection algorithms indicating the underlying mechanism of creation. Further properties of the space-time network are identified and reveal underlying mechanisms to account for elusive and anomalous physical phenomenon including non-locality, quantum entanglement and quantum gravity.
Spacetime Emergence in Quantum Gravity: Functionalism and the Hard Problem
Synthese, 2019
Spacetime functionalism is the view that spacetime is a functional structure implemented by a more fundamental ontology. Lam and Wüthrich have recently argued that spacetime functionalism helps to solve the epistemological problem of empirical coherence in quantum gravity and suggested that it also (dis)solves the hard problem of spacetime, namely the problem of offering a picture consistent with the emergence of spacetime from a non-spatio-temporal structure. First, I will deny that spacetime functionalism solves the hard problem by showing that it comes in various species, each entailing a different attitude towards, or answer to, the hard problem. Second, I will argue that the existence of an explanatory gap, which grounds the hard problem, has not been correctly taken into account in the literature.