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Related papers: On the measurements in Quantum Gravity

200 papers

A discussion of the meaning of a physical concept cannot be separated from discussion of the conditions for its ideal measurement. We assert that quantization is no more than the invocation of the quantum of action in the explanation of…

General Relativity and Quantum Cosmology · Physics 2014-01-14 John Stachel , Kaća Bradonjić

A prominent formulation of the uncertainty principle identifies the fundamental quantum feature that no particle may be prepared with certain outcomes for both position and momentum measurements. Often the statistical uncertainties are…

Quantum Physics · Physics 2015-01-08 Fabian Furrer , Mario Berta , Marco Tomamichel , Volkher B. Scholz , Matthias Christandl

While a positive operator valued measure gives the probabilities in a quantum measurement, an instrument gives both the probabilities and the a posteriori states. By interpreting the instrument as a quantum channel and by using the…

Quantum Physics · Physics 2007-05-23 Alberto Barchielli , Giancarlo Lupieri

Combining gravity with quantum theory is still work in progress. On the one hand, classical gravity, is the geometry of space-time determined by the energy-momentum tensor of matter and the resulting nonlinear equations; on the other hand,…

Quantum Physics · Physics 2024-01-26 P. Gusin , D. Burys , A. Radosz

There exist several different proposals for a measure in Quantum Gravity theories. Although sometimes being labelled as non covariant, the measure derived in [7] for GR has the particularity that, in the extremal, the volume divergences…

General Relativity and Quantum Cosmology · Physics 2026-03-05 O. P. Santillán

Black holes in equilibrium and the counting of their entropy within Loop Quantum Gravity are reviewed. In particular, we focus on the conceptual setting of the formalism, briefly summarizing the main results of the classical formalism and…

General Relativity and Quantum Cosmology · Physics 2009-01-12 Alejandro Corichi

Quantum metrology uses small changes in the output probabilities of a quantum measurement to estimate the magnitude of a weak interaction with the system. The sensitivity of this procedure depends on the relation between the input state,…

Quantum Physics · Physics 2011-03-02 Holger F. Hofmann

The question of general covariance in quantum gravity is considered in the first post-Newtonian approximation. Transformation properties of observable quantities under deformations of a reference frame, induced by variations of the gauge…

High Energy Physics - Theory · Physics 2009-11-07 Kirill A. Kazakov

Microscopic state counting for a black hole in Loop Quantum Gravity yields a result proportional to horizon area, and inversely proportional to Newton's constant and the Immirzi parameter. It is argued here that before this result can be…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Ted Jacobson

In two articles, the authors claim that the Heisenberg uncertainty principle limits the precision of simultaneous measurements of the position and velocity of a particle and refer to experimental evidence that supports their claim. It is…

General Physics · Physics 2007-07-12 Elias P. Gyftopoulos

Heisenberg uncertainty principle describes a basic restriction on observer's ability of precisely predicting the measurement for a pair of non-commuting observables, and virtually is at the core of quantum mechanics. We herein aim to study…

Quantum Physics · Physics 2018-09-21 Dong Wang , Wei-Nan Shi , Ross D. Hoehn , Fei Ming , Wen-Yang Sun , Sabre Kais , Liu Ye

Quantum measurements are not deterministic. For this reason quantum measurements are repeated for a number of shots on identically prepared systems. The uncertainty in each measurement depends on the number of shots and the expected outcome…

Quantum Physics · Physics 2025-03-12 Pieter Thijs Eendebak

We evoke situations where large fluctuations in the entropy are induced, our main example being a spacetime containing a potential black hole whose formation depends on the outcome of a quantum mechanical event. We argue that the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Rafael Sorkin , Daniel Sudarsky

By invoking quantum estimation theory we formulate bounds of errors in quantum measurement for arbitrary quantum states and observables in a finite-dimensional Hilbert space. We prove that the measurement errors of two observables satisfy…

Quantum Physics · Physics 2013-05-29 Yu Watanabe , Takahiro Sagawa , Masahito Ueda

In this work we investigate how to quantify the coherence of quantum measurements. First, we establish a resource theoretical framework to address the coherence of measurement and show that any statistical distance can be adopted to define…

Quantum Physics · Physics 2020-08-11 Kyunghyun Baek , Adel Sohbi , Jaehak Lee , Jaewan Kim , Hyunchul Nha

The existence of minimal length scale has motivated the proposal of generalized uncertainty principle, which provides a potential routine to probe quantum gravitational effects in low-energy quantum mechanics experiment. Hitherto, the…

Quantum Physics · Physics 2016-02-26 Yue-Yue Chen , Xun-Li Feng , C. H. Oh , Zhi-Zhan Xu

Various theories that aim at unifying gravity with quantum mechanics suggest modifications of the Heisenberg algebra for position and momentum. From the perspective of quantum mechanics, such modifications lead to new uncertainty relations…

The issue of black hole entropy is reexamined within a finite lattice framework along the lines of Wheeler, 't Hooft and Susskind, with an additional criterion to identify physical horizon states contributing to the entropy. As a…

High Energy Physics - Theory · Physics 2007-05-23 Parthasarathi Majumdar

We discuss some issues related to the computation of black hole entropy in loop quantum gravity from the novel point of view provided by the recent number-theoretical methods introduced by the authors and their collaborators. In particular…

General Relativity and Quantum Cosmology · Physics 2010-05-19 J. Fernando Barbero G. , Eduardo J. S. Villaseñor

One of the leading issues in quantum field theory and cosmology is the mismatch between the observed and calculated values for the cosmological constant in Einstein's field equations of up to 120 orders of magnitude. In this paper, we…

General Relativity and Quantum Cosmology · Physics 2023-09-21 Michael Bishop , Peter Martin , Douglas Singleton