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Related papers: Quantum Cosmology from Group Field Theory Condensa…

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The condensate cosmology programme of group field theory has produced several interesting results. The key idea is in the suggestion that a macroscopic homogeneous spacetime can be approximated by a dynamical condensate phase of the…

General Relativity and Quantum Cosmology · Physics 2020-08-18 Mehdi Assanioussi , Isha Kotecha

We construct a generalized class of quantum gravity condensate states, that allows the description of continuum homogeneous quantum geometries within the full theory. They are based on similar ideas already applied to extract effective…

General Relativity and Quantum Cosmology · Physics 2015-11-24 Daniele Oriti , Daniele Pranzetti , James P. Ryan , Lorenzo Sindoni

We extend various recent results regarding the derivation of effective cosmological Friedmann equations from the dynamics of group field theory (GFT). Restricting ourselves to a single GFT field mode (or fixed values of Peter-Weyl…

General Relativity and Quantum Cosmology · Physics 2022-01-11 Steffen Gielen , Axel Polaczek

Following the idea of a field quantization of gravity as realized in group field theory, we construct a minisuperspace model where the wavefunction of canonical quantum cosmology (either Wheeler-DeWitt or loop quantum cosmology) is promoted…

General Relativity and Quantum Cosmology · Physics 2012-05-02 Gianluca Calcagni , Steffen Gielen , Daniele Oriti

We study the effective cosmological dynamics, emerging as the hydrodynamics of simple condensate states, of a group field theory model for quantum gravity coupled to a massless scalar field and reduced to its isotropic sector. The quantum…

General Relativity and Quantum Cosmology · Physics 2016-11-23 Daniele Oriti , Lorenzo Sindoni , Edward Wilson-Ewing

Group field theory (GFT) models for quantum gravity coupled to a massless scalar field give rise to cosmological models that reproduce the (expanding or contracting) dynamics of homogeneous and isotropic spacetimes in general relativity at…

High Energy Physics - Theory · Physics 2023-07-27 Steffen Gielen , Robert Santacruz

Spatially homogeneous universes can be described in (loop) quantum gravity as condensates of elementary excitations of space. Their treatment is easiest in the second-quantised group field theory formalism which allows the adaptation of…

General Relativity and Quantum Cosmology · Physics 2014-07-24 Steffen Gielen

For more than 80 years theoretical physicists have been trying to develop a theory of quantum gravity which would successfully combine the tenets of Einstein's theory of general relativity (GR) together with those of quantum field theory.…

General Relativity and Quantum Cosmology · Physics 2019-03-20 Andreas G. A. Pithis

Quantum field theory (QFT) on fractal spacetimes is a program aiming at quantizing the gravitational interaction consistently at all energy scales thanks to an intrinsically or dynamically induced multiscale or multifractal-like spacetime…

High Energy Physics - Theory · Physics 2026-03-26 Fabio Briscese , Gianluca Calcagni

We show that the effective dynamics of the recently proposed isotropic condensate state of group field theory with Laplacian kinetic operator can be equivalent to that of homogeneous and isotropic loop quantum cosmology in the improved…

General Relativity and Quantum Cosmology · Physics 2014-09-30 Gianluca Calcagni

We offer a perspective on some recent results obtained in the context of the group field theory approach to quantum gravity, on top of reviewing them briefly. These concern a natural mechanism for the emergence of non-commutative field…

High Energy Physics - Theory · Physics 2009-07-24 Daniele Oriti

We give a very brief introduction to the group field theory approach to quantum gravity, a generalisation of matrix models for 2-dimensional quantum gravity to higher dimension, that has emerged recently from research in spin foam models.

General Relativity and Quantum Cosmology · Physics 2015-06-25 Daniele Oriti

In the context of group field theory condensate cosmology, we clarify the extraction of cosmological variables from the microscopic quantum gravity degrees of freedom. We show that an important implication of the second quantized formalism…

General Relativity and Quantum Cosmology · Physics 2014-12-03 Steffen Gielen , Daniele Oriti

In this paper I offer an introduction to group field theory (GFT) and to some of the issues affecting the foundations of this approach to quantum gravity. I first introduce covariant GFT as the theory that one obtains by interpreting the…

General Relativity and Quantum Cosmology · Physics 2024-06-14 Álvaro Mozota Frauca

While the equations of general relativity take the same form in any coordinate system, choosing a suitable set of coordinates is essential in any practical application. This poses a challenge in background-independent quantum gravity, where…

General Relativity and Quantum Cosmology · Physics 2018-10-03 Steffen Gielen

We propose a new method for obtaining an effective Friedmann-Lema\^itre-Robertson-Walker (FLRW) cosmology from the quantum gravity dynamics of group field theory (GFT), based on the idea that an FLRW universe is characterised by a few…

General Relativity and Quantum Cosmology · Physics 2022-03-10 Steffen Gielen , Luca Marchetti , Daniele Oriti , Axel Polaczek

Many candidate models for dark energy are based on the existence of a classical scalar field. In the context of Quantum Field Theory (QFT), we briefly discus the condensation of such a field from a light quantum scalar field produced by…

High Energy Physics - Phenomenology · Physics 2011-12-19 Houri Ziaeepour

Loop quantum cosmology is a symmetry reduced quantization of cosmological spacetimes based on loop quantum gravity. While it has been successful in resolution of various cosmological singularities and connecting Planck scale physics to…

General Relativity and Quantum Cosmology · Physics 2019-12-25 Klaus Liegener , Parampreet Singh

This contribution is an appetizer to the relatively young and fast evolving approach to quantum cosmology based on group field theory condensate states. We summarize the main assumptions and pillars of this approach which has revealed new…

General Relativity and Quantum Cosmology · Physics 2019-06-14 A. G. A. Pithis , M. Sakellariadou

We construct a 2nd quantized reformulation of canonical Loop Quantum Gravity at both kinematical and dynamical level, in terms of a Fock space of spin networks, and show in full generality that it leads directly to the Group Field Theory…

General Relativity and Quantum Cosmology · Physics 2015-08-19 Daniele Oriti