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Related papers: Time and Causation

200 papers

I suggest that measurement in quantum theory should be regarded as a sense of time (of things happening), which is as important as the conventional relativistic notion of time. A key question -- of basic physical interest whether one…

General Relativity and Quantum Cosmology · Physics 2008-12-15 Adam Helfer

Quantum theory depends on an external classical time, and there ought to exist an equivalent reformulation of the theory which does not depend on such a time. The demand for the existence of such a reformulation suggests that quantum theory…

Quantum Physics · Physics 2012-10-31 Tejinder P. Singh

With a view to the results discussed in the first two parts of this paper, the concept of time is revisited oncemore and chosen as an example in order to demonstrate the meaning of fundamental in both physical and philosophical terms. It is…

General Physics · Physics 2007-05-23 Rainer E. Zimmermann

We take causality and uniqueness of events observation as our driving forces. They are built in in the way we define distinct observers, which then require a finite time to communicate between each other. This unavoidably leads to the…

General Physics · Physics 2026-04-09 Antonio Pineda

One of the most fundamental open problems in physics is the unification of general relativity and quantum theory to a theory of quantum gravity. An aspect that might become relevant in such a theory is that the dynamical nature of causal…

Quantum Physics · Physics 2022-03-14 Veronika Baumann , Marius Krumm , Philippe Allard Guérin , Časlav Brukner

With special relativity, we seem to be facing a conundrum. It is a very well-tested theory; in this way, the Minkowski spacetime must be "capturing" essential features of space and time. However, its geometry seems to be incompatible with…

History and Philosophy of Physics · Physics 2024-09-10 Mario Bacelar Valente

We describe a link between the cosmological constant problem and the problem of time in quantum gravity. This arises by examining the relationship between the cosmological constant and vacuum energy in light of non-perturbative formulations…

General Relativity and Quantum Cosmology · Physics 2010-03-12 Viqar Husain

In prior work, we have argued that spacetime functionalism provides tools for clarifying the conceptual difficulties specifically linked to the emergence of spacetime in certain approaches to quantum gravity. We argue in this article that…

History and Philosophy of Physics · Physics 2020-03-24 Vincent Lam , Christian Wuthrich

Attempts to quantize general relativity encounter an odd problem. The Hamiltonian that normally generates time evolution vanishes in the case of general relativity as a result of diffeomorphism invariance. The theory seems to be saying that…

General Relativity and Quantum Cosmology · Physics 2009-04-23 Olaf Dreyer

We apply the causal interpretation of quantum mechanics to homogeneous quantum cosmology and show that the quantum theory is independent of any time-gauge choice and there is no issue of time. We exemplify this result by studying a…

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. Acacio de Barros , N. Pinto-Neto

Some authors in the quantum gravity community endorse, explicitly or implicitly, a radical relationalist view of time which states that the ordinal structure of time is not needed even in our classical theories, especially in general…

History and Philosophy of Physics · Physics 2025-05-14 Álvaro Mozota Frauca

We consider two type of systems, a linear singular discrete time system and a linear singular fractional discrete time system whose coefficients are square constant matrices. By assuming that the input vector changes only at equally space…

Dynamical Systems · Mathematics 2015-12-16 Nicholas Apostolopoulos , Fernando Ortega , Grigoris Kalogeropoulos

Causal fermion systems are introduced as a general mathematical framework for formulating relativistic quantum theory. By specializing, we recover earlier notions like fermion systems in discrete space-time, the fermionic projector and…

Mathematical Physics · Physics 2014-06-17 Felix Finster , Andreas Grotz , Daniela Schiefeneder

`How do our ideas about quantum mechanics affect our understanding of spacetime?' This familiar question leads to quantum gravity. The complementary question is also important: `How do our ideas about spacetime affect our understanding of…

General Relativity and Quantum Cosmology · Physics 2009-11-11 James B. Hartle

An important task faced by all approaches of quantum gravity is to incorporate superpositions and quantify quantum uncertainties of spacetime causal relations. We address this task in 2D. By identifying a global $Z_2$ symmetry of 1+1D…

General Relativity and Quantum Cosmology · Physics 2022-03-03 Ding Jia

In general relativity, the picture of spacetime assigns an ideal clock to each worldline. Being ideal, gravitational effects due to these clocks are ignored and the flow of time according to one clock is not affected by the presence of…

Quantum Physics · Physics 2017-05-09 Esteban Castro-Ruiz , Flaminia Giacomini , Časlav Brukner

Curvature is a key notion in General Relativity, characterizing the local physical properties of spacetime. By contrast, the concept of curvature has received scant attention in nonperturbative quantum gravity. One may even wonder whether…

General Relativity and Quantum Cosmology · Physics 2023-06-27 R. Loll

Based on the hypothesis that the thermodynamic arrow of time is an emergent phenomenon of quantum state complexity evolution, we further propose that the natural pace of time flow is proportional to the changing rate of quantum state…

Quantum Physics · Physics 2018-01-17 X. Dong , L. Zhou

We discuss a number of comments on quant-ph/9801061, and propose to introduce the concept of 'Causal Indistinguishability'. The incompatibility between Quantum Mechanics and Nonlocal Causality appears to be unavoidable: upholding of Quantum…

Quantum Physics · Physics 2007-05-23 Antoine Suarez

This paper puts forward a broad critical analysis of the concept of physical time. Clock effect is conceived as a consequence of the variation of the gravitational or pseudo gravitational potential, and it is remarked that only some real…

General Physics · Physics 2018-09-05 Claudio Borghi