181 citations · 727 across the 33 of their papers we have counts for
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Consistent Gauge Conditions for Dust-Shell Dynamics in Effective Quantum Gravity
Dongxue Qu, Cong Zhang
Previous analyses of shocks generated by shell-crossing singularities are affected by inappropriate gauge choices, and no systematic method is available for selecting a consistent…
Covariant effective spacetimes of spherically symmetric electrovacuum with a cosmological constant
Jinsong Yang, Cong Zhang, Yongge Ma
An algebraic framework was introduced in our previous works to address the covariance issue in spherically symmetric effective quantum gravity. This paper extends the framework to…
Black holes and covariance in effective quantum gravity: A solution without Cauchy horizons
Cong Zhang, Jerzy Lewandowski, Yongge Ma +1
The issue of general covariance in effective quantum gravity models within the Hamiltonian framework is addressed. The previously proposed equations for the covariance condition in…
Black Holes and Covariance in Effective Quantum Gravity
Cong Zhang, Jerzy Lewandowski, Yongge Ma +1
The longstanding issue of general covariance in effective models of quantum gravity is addressed, which arises when canonical quantum gravity leads to a semiclassical model describ…
Conformally Invariant Brans-Dicke Loop Quantum Cosmology: A Quantum Geometric Model of Linking Theory
Chun-Yen Lin, Xiangjing Liu, Yongge Ma +1
The loop quantization of the conformal Brans-Dicke cosmology is explored in the spatially flat and Bianchi-I setting. The scalar and conformal constraints governing the canonical m…
Black hole image encoding quantum gravity information
Cong Zhang, Yongge Ma, Jinsong Yang
The quantum extension of the Kruskal spacetime indicates the existence of a companion black hole in the universe earlier than ours. It is shown that the radiations from the compani…
Fermions in Loop Quantum Gravity and Resolution of Doubling Problem
Cong Zhang, Hongguang Liu, Muxin Han
The fermion propagator is derived in detail from the model of fermion coupled to loop quantum gravity. As an ingredient of the propagator, the vacuum state is defined as the ground…
Alternative loop quantum cosmology
Jinsong Yang, Cong Zhang, Xiangdong Zhang
An alternative quantization of the gravitational Hamiltonian constraint of the Friedmann-Robertson-Walker model is proposed by treating the Euclidean term and the Lorentzian…
Shadow and stability of quantum-corrected black holes
Jinsong Yang, Cong Zhang, Yongge Ma
Recently the quantum Oppenheimer-Snyder gravitational collapse model has been proposed in loop quantum gravity, providing quantum-corrected Schwarzschild spacetimes as the exterior…
Quantum Oppenheimer-Snyder and Swiss Cheese models
Jerzy Lewandowski, Yongge Ma, Jinsong Yang +1
By considering the quantum Oppenheimer-Snyder model in loop quantum cosmology, a new quantum black hole model whose metric tensor is a suitably deformed Schwarzschild one is derive…
Fermions on Quantum Geometry and Resolution of Doubling Problem
Cong Zhang, Hongguang Liu, Muxin Han
The fermion doubling problem has an important impact on quantum gravity, by revealing the tension between fermion and the fundamental discreteness of quantum spacetime. In this wor…
The thermodynamics of isolated horizons in loop quantum gravity
Shupeng Song, Gaoping Long, Cong Zhang +1
The statistical mechanical calculation of the thermodynamical properties of non-rotating isolated horizons are studied in the loop quantum gravity framework. By employing the Hawki…
Fermion coupling to loop quantum gravity: canonical formulation
Jerzy Lewandowski, Cong Zhang
In the model of a fermion field coupled to loop quantum gravity, we consider the Gauss and the Hamiltonian constraints. According to the explicit solutions to the Gauss constraint,…
Twisted geometry coherent states in all dimensional loop quantum gravity: I. Construction and Peakedness properties
Gaoping Long, Xiangdong Zhang, Cong Zhang
A new family of coherent states for all dimensional loop quantum gravity are proposed, which is based on the generalized twisted geometry parametrization of the phase space of $SO(…
Loop quantum deparametrized Schwarzschild interior and discrete black hole mass
Cong Zhang, Yongge Ma, Shupeng Song +1
We present the detailed analyses of a model of loop quantum Schwarzschild interior coupled to a massless scalar field and extend the results in our previous rapid communication arX…
Reduced Phase Space Quantization of Black Holes: Path Integrals, and Effective Dynamics
Cong Zhang
We consider the loop quantum theory of the spherically symmetric model of gravity coupled to Gaussian dust fields, where the Gaussian dust fields provide a material reference frame…
Superposition type coherent states in all dimensional loop quantum gravity
Gaoping Long, Cong Zhang, Xiangdong Zhang
We propose a new kind of coherent state for the general formulation of loop quantum gravity in the -dimensional space-time. Instead of Thiemann's coherent state fo…
Relating spin-foam to canonical loop quantum gravity by graphical calculus
Jinsong Yang, Cong Zhang, Yongge Ma
The graphical calculus method is generalized to study the relation between covariant and canonical dynamics of loop quantum gravity. On one hand, a graphical derivation of the part…
First-Order Quantum Correction in Coherent State Expectation Value of Loop-Quantum-Gravity Hamiltonian
Cong Zhang, Shicong Song, Muxin Han
Given the non-graph-changing Hamiltonian in Loop Quantum Gravity (LQG), , the coherent state expectation value of , a…
First-Order Quantum Correction in Coherent State Expectation Value of Loop-Quantum-Gravity Hamiltonian: Overview and Results
Cong Zhang, Shicong Song, Muxin Han
Given the Loop-Quantum-Gravity (LQG) non-graph-changing Hamiltonian , the coherent state expectation value admits an semiclassical ex…
Loop quantum cosmology from an alternative Hamiltonian. II. Including the Lorentzian term
Jinsong Yang, Cong Zhang, Yongge Ma
The scheme of using the Chern-Simons action to regularize the gravitational Hamiltonian constraint is extended to including the Lorentzian term in the cosmological model. The…
Loop quantum Schwarzschild interior and black hole remnant
Cong Zhang, Yongge Ma, Shupeng Song +1
The interior of Schwarzschild black hole is quantized by the method of loop quantum gravity. The Hamiltonian constraint is solved and the physical Hilbert space is obtained in the…
Alternative dynamics in loop quantum Brans-Dicke cosmology
Shupeng Song, Cong Zhang, Yongge Ma
To inherit more features of full loop quantum Brans-Dicke theory, the Euclidean and Lorentzian terms of the Hamiltonian constraint are quantized independently in loop quantum Brans…
Entropy of black holes with arbitrary shapes in loop quantum gravity
Shupeng Song, Haida Li, Yongge Ma +1
The quasi-local notion of an isolated horizon is employed to study the entropy of black holes without any particular symmetry in loop quantum gravity. The idea of characterizing th…