Quantum physics and Einstein’s theory of general relativity are the two main pillars that underlie much of modern physics. Ordinary quantum field theories, which combine classical field theory, special relativity and quantum mechanics, are an excellent approximation when describing the behaviour of microscopic particles in weak gravitational fields. At high energies, however, not every quantum field theory can be consistently coupled to gravity at quantum level, unless it satisfies some additional novel set of conditions known as Swampland constraints.
The EU-funded QGuide project aims to determine the constraints that quantum gravity imposes at low energies. To this end, the team members will uncover the fundamental principles underlying the Swampland conjectures, and look for new universal constraints in the context of string theory. This can have profound implications for Particle Physics and Cosmology, providing new guiding principles to progress in High Energy Physics.
To achieve this goal, the project uses a novel approach based on cutting edge mathematical techniques of algebraic geometry and the topological cobordism groups that extend the notion of symmetry. Each swampland conjecture is subject to scrutiny such that it gets either disproven or promoted to a sharp statement in the realm of well-established string compactifications.
Specific goals include an in-depth analysis of the mechanisms by which string theory avoids new classes of generalised global symmetries, a complete classification of the field spectra emerging at the large field limits of flat space string compactifications, developing new methods to study the scalar potential at the large field limits and determining whether supersymmetry is a necessary condition to ensure vacuum stability.
These new quantum gravity constraints may trigger a revolution in our understanding of the Quantum Gravity imprint at low energies, addressing questions about axions, neutrino masses, inflation, hierarchy problems, weakly coupled charged matter and the accelerated expansion of the universe.
