Scope and Topic

Quantum gravity aims at a radical new understanding of the nature of space and time. The
quantum description of continuum space-time geometry, the most direct implication of a
quantization of the gravitational field, would already represent a big challenge to traditional
notions of space and time. Many modern approaches go beyond this by proposing as
fundamental constituents of space-time structures that are discrete and/or non-geometric in
nature. If the fundamental structures of quantum gravity are not spatio-temporal, space and
time are necessarily ‘emergent’ notions. The first subject of the workshop will be the notion
of the emergence of space and time in various quantum gravity approaches.

The pre-geometric building blocks of such emergent spacetime would be subject to
quantum mechanical laws, in particular quantum entanglement. Emergent spacetime
scenarios in quantum gravity are therefore also the natural setting to explore the idea that
quantum entanglement (and other tools of quantum information) is the key for the very
emergence of geometry, and the texture of spacetime itself, the second idea the workshop
will focus on.

Quantum gravity effects are expected to become important in the very early universe and in
particular to resolve the initial big-bang singularity. The cosmological sector of quantum
gravity is also particularly interesting to explore due to the possibility that quantum gravity
effects could potentially be tested via high precision observations of the cosmic microwave
background. The third topic of the workshop concerns the quantum nature of the early
universe and in particular the role that the emergence of space-time may play in various
cosmological models of the early universe, both with respect to singularity resolution and
structure formation.

If understood as a physical process (possibly in the form of a phase transition), the
emergence of time and space in quantum gravity could also be tentatively linked with the
very initial stage of cosmological evolution as the quantum process that replaces the
cosmological big bang singularity in quantum gravity. This may suggest a radical new
description of early cosmology. The possible cosmological nature of the emergence of time
and space and its conceptual and phenomenological consequences will be the fourth focus
of the workshop.

 

 

LQGspacetime