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Related papers: Fuzzy spacetime from a null-surface version of GR

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The phenomenologically observed flatness - or near flatness - of spacetime cannot be understood as emerging from continuum Planck (or sub-Planck) scales using known physics. Using dimensional arguments it is demonstrated that any…

General Relativity and Quantum Cosmology · Physics 2013-06-14 D. Bennett , H. B. Nielsen

From general relativity we have learned the principles of general covariance and local Lorentz invariance, which follow from the fact that we consider observables as tensors on a spacetime manifold whose geometry is modeled by a Lorentzian…

Mathematical Physics · Physics 2014-09-12 Manuel Hohmann

We provide here a philosophical basis for [arXiv:2012.03994, arXiv:2107.06693] based on the notion of spacetime relationalism. We argue that the view which is more cleanly compatible with GR is that in which the spacetime manifold is a…

General Relativity and Quantum Cosmology · Physics 2021-09-21 Alejandro Ascárate

The Einstein theories of space-time and gravity as well the stander cosmology are reconstructed thoroughly in this paper based on flat reference frame. The rational parts of the Einstein theories are reserved while the irrational parts…

General Physics · Physics 2007-05-23 Mei Xiaochun

Treating the gravitational force on the same footing as the electroweak and strong forces, we present a quantum field theory of gravity based on spin and scaling gauge symmetries. A biframe spacetime is initiated to describe such a quantum…

High Energy Physics - Theory · Physics 2016-01-20 Yue-Liang Wu

We propose a new framework of quantum field theory for an arbitrary observer in curved spacetime, defined in the spacetime region in which each point can both receive a signal from and send a signal to the observer. Multiple motivations for…

General Relativity and Quantum Cosmology · Physics 2009-07-16 Hui Yao

A novel theory of Quantum Gravity is presented in which the real gravitons manifest themselves as holes in space. In general, these holes propagate at the speed of light through an expanding universe with boundary denoted by U, which is…

General Physics · Physics 2015-08-26 Gregory W. Horndeski

The questions of describing observables and observation in quantum gravity appear to be centrally important to its physics. A relational approach holds significant promise, and a classification of different types of relational observables…

High Energy Physics - Theory · Physics 2025-06-13 Steven B. Giddings

A surface theoretic view of non-perturbative quantum gravity as "spin-foams" was proposed by Baez. A possibility of constructing such a model was studied some time ago based on (2+1) dimensional general relativity as a reformulation of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Junichi Iwasaki

An introduction is given to discussions on the possiblity of fabricating spacetime geometries allowing time-travel scenarios with the help of matter possessing typically quantum features. Those scenarios are considered in the framework of…

Popular Physics · Physics 2013-06-27 Rainer Verch

The `observer space' of a Lorentzian spacetime is the space of future-timelike unit tangent vectors. Using Cartan geometry, we first study the structure a given spacetime induces on its observer space, then use this to define abstract…

General Relativity and Quantum Cosmology · Physics 2013-05-08 Steffen Gielen , Derek K. Wise

The geometrical nature of gravity emerges from the universality dictated by the equivalence principle. In the usual formulation of General Relativity, the geometrisation of the gravitational interaction is performed in terms of the…

High Energy Physics - Theory · Physics 2019-03-19 Jose Beltran Jimenez , Lavinia Heisenberg , Tomi S. Koivisto

We construct a canonical formulation of general relativity for the case of a timelike foliation of spacetime. The formulation possesses explicit covariance with respect to Lorentz transformations in the tangent space. Applying the loop…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Sergei Alexandrov , Zoltan Kadar

We introduce observables associated with the space-time position of a quantum point defined by the intersection of two light pulses. The time observable is canonically conjugated to the energy. Conformal symmetry of massless quantum fields…

Quantum Physics · Physics 2009-10-30 Marc-Thierry Jaekel , Serge Reynaud

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

In a natural extension of the relativity principle we argue that a quantum theory of gravity involves two fundamental scales associated with both dynamical space-time as well as dynamical momentum space. This view of quantum gravity is…

High Energy Physics - Theory · Physics 2015-06-19 Laurent Freidel , Robert G. Leigh , Djordje Minic

The Einstein theories of space-time and gravity as well the stander cosmology are reconstructed thoroughly in this paper based on flat reference frame. The rational parts of the Einstein theories are reserved while the irrational parts…

General Physics · Physics 2007-05-23 Mei Xiaochun

We present the case for a fundamentally discrete quantum spacetime and for Group Field Theories as a candidate consistent description of it, briefly reviewing the key properties of the GFT formalism. We then argue that the outstanding…

High Energy Physics - Theory · Physics 2008-11-26 Daniele Oriti

We develop the spectral point of view on geometry based on the formalism of quantum physics. We start from the simple physical question of specifying our position in space and explain how the spectral geometric point of view provides a new…

High Energy Physics - Theory · Physics 2019-04-11 Ali H. Chamseddine , Alain Connes

General relativity is incomplete because it cannot describe quantum effects of space-time. The complete theory of quantum gravity is not yet known and to date no observational evidence exists that space-time is quantized. However, in most…

General Relativity and Quantum Cosmology · Physics 2018-07-17 Sabine Hossenfelder , Ricardo Gallego Torromé