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Related papers: A Dynamics for Discrete Quantum Gravity

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With approaching quantum/noncommutative models for the deep microscopic spacetime in mind, and inspired by our recent picture of the (projective) Hilbert space as the model of physical space behind basic quantum mechanics, we reformulate…

Quantum Physics · Physics 2021-01-13 Chuan Sheng Chew , Otto C. W. Kong , Jason Payne

A classical precursor to a full quantum dynamics for causal sets has been forumlated in terms of a stochastic sequential growth process in which the elements of the causal set arise in a sort of accretion process. The transition…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Madhavan Varadarajan , David Rideout

We study quantum cosmology with conformal matter comprising a perfect radiation fluid and a number of conformally coupled scalar fields. Focusing initially on the collective coordinates (minisuperspace) associated with homogeneous,…

High Energy Physics - Theory · Physics 2016-07-07 Steffen Gielen , Neil Turok

We study how meaningful physical predictions can arise in nonperturbative quantum gravity in a closed Lorentzian universe. In such settings, recent developments suggest that the quantum gravitational Hilbert space is one-dimensional and…

High Energy Physics - Theory · Physics 2025-06-17 Yasunori Nomura , Tomonori Ugajin

We describe a simple gauge-fixing that leads to a construction of a quantum Hilbert space for quantum gravity in an asymptotically Anti de Sitter spacetime, valid to all orders of perturbation theory. The construction is motivated by a…

High Energy Physics - Theory · Physics 2023-06-28 Edward Witten

Within the causal set approach to quantum gravity, a discrete analog of a spacelike region is a set of unrelated elements, or an antichain. In the continuum approximation of the theory, a moment-of-time hypersurface is well represented by…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Seth Major , David Rideout , Sumati Surya

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

The simple algorithm for the simulation and visualization of non relativistic quantum dynamics is proposed that is based on a collective behavior of classical particles. Any quantum particle is represented as the swarm of its classical…

Quantum Physics · Physics 2007-05-23 Yuri Ozhigov

The novel idea is that the undergoing accelerated expansion of the universe happens due to infrared quantum gravity modifications at intermediate astrophysical scales of galaxies or galaxy clusters, within the framework of Asymptotically…

General Relativity and Quantum Cosmology · Physics 2021-02-16 Fotios K. Anagnostopoulos , Georgios Kofinas , Vasilios Zarikas

Causal Dynamical Triangulations is a background independent approach to quantum gravity. In this paper we introduce a phenomenological transfer matrix model, where at each time step a reduced set of quantum states is used. The states are…

High Energy Physics - Theory · Physics 2013-02-06 Andrzej Görlich

The formalism of causal dynamical triangulations (CDT) provides us with a non-perturbatively defined model of quantum gravity, where the sum over histories includes only causal space-time histories. Path integrals of CDT and their continuum…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. Ambjorn , R. Loll , W. Westra , S. Zohren

We introduce a family of hybrid quantum circuits involving unitary gates and projective measurements that display a measurement-induced phase transition. Remarkably, the volume-law phase featuring logarithmic entanglement growth for certain…

Quantum Physics · Physics 2025-10-09 Vikram Ravindranath , Hanchen Liu , Xiao Chen

To solve the path integral for quantum gravity, one needs to regularise the space-times that are summed over. This regularisation usually is a discretisation, which makes it necessary to give up some paradigms or symmetries of continuum…

General Relativity and Quantum Cosmology · Physics 2014-09-30 Lisa Glaser

We identify a class of condensate states in the group field theory (GFT) approach to quantum gravity that can be interpreted as macroscopic homogeneous spatial geometries. We then extract the dynamics of such condensate states directly from…

General Relativity and Quantum Cosmology · Physics 2013-07-17 Steffen Gielen , Daniele Oriti , Lorenzo Sindoni

I develop Rafael D. Sorkin's proposal that a partially ordered process of the birth of spacetime atoms in causal set quantum gravity provides an objective physical correlate of our perception of time passing. I argue that one cannot have a…

General Relativity and Quantum Cosmology · Physics 2023-05-23 Fay Dowker

We consider a quantization of relativistic wave equations which allows to treat quantum fields together with interacting particles at a finite time. We discuss also a dissipative interaction with the environment. We introduce a stochastic…

High Energy Physics - Theory · Physics 2007-05-23 Z. Haba

By quantising the gravitational dynamics, space and time are usually forced to play fundamentally different roles. This raises the question whether physically relevent configurations could also exist which would not admit…

General Relativity and Quantum Cosmology · Physics 2015-07-16 Pierre A. Mandrin

We introduce a new top down approach to canonical quantum gravity, called Algebraic Quantum Gravity (AQG):The quantum kinematics of AQG is determined by an abstract $*-$algebra generated by a countable set of elementary operators labelled…

General Relativity and Quantum Cosmology · Physics 2008-11-26 K. Giesel , T. Thiemann

Several approaches to the dynamics of loop quantum gravity involve discretizing the equations of motion. The resulting discrete theories are known to be problematic since the first class algebra of constraints of the continuum theory…

General Relativity and Quantum Cosmology · Physics 2009-01-16 Rodolfo Gambini , Jorge Pullin

In a previous work [arXiv:2009.03428] we proposed a new model for Quantum GRavity(QGR) and cosmology, dubbed $SU(\infty)$-QGR. One of the axioms of this model is that Hilbert spaces of the Universe and its subsystems represent $SU(\infty)$…

General Relativity and Quantum Cosmology · Physics 2022-01-04 Houri Ziaeepour