中文
相关论文

相关论文: Dirac Fields in Loop Quantum Gravity and Big Bang …

200 篇论文

We discuss the way non-perturbative quantization of cosmological spacetimes in loop quantum cosmology provides insights on the physics of Planck scale and the resolution of big bang singularity. In recent years, rigorous examination of…

广义相对论与量子宇宙学 · 物理学 2009-03-27 Parampreet Singh

We consider the effects of the time dependence of couplings due to their dependence on a dilaton field, as occurs in superstring theory, as well as in gravity theories of the Jordan-Brans-Dicke type. Because the scale parameters of…

高能物理 - 唯象学 · 物理学 2009-09-15 Bruce A. Campbell , Keith A. Olive

The existing approaches to quantization of gravity aim at giving quantum description of 3-geometry following to the ideas of the Wheeler -- DeWitt geometrodynamics. In this description the role of gauge gravitational degrees of freedom is…

广义相对论与量子宇宙学 · 物理学 2012-05-31 T. P. Shestakova

We consider the effective theory of perturbative quantum gravity coupled to a point particle, quantizing fluctuations of both the gravitational field and the particle's position around flat space. Using a recent relational approach to…

高能物理 - 理论 · 物理学 2022-02-02 M. B. Fröb , C. Rein , R. Verch

Big Bang Nucleosynthesis (BBN) offers one of the most strict evidences for the Lambda-CDM cosmology at present, as well as the Cosmic Microwave Background (CMB) radiation. In this work, our main aim is to present the outcomes of our…

宇宙学与河外天体物理 · 物理学 2014-09-10 Sibel Boran , Emre Onur Kahya

The theory of scale relativity provides a new insight into the origin of fundamental laws in physics. Its application to microphysics allows us to recover quantum mechanics as mechanics on a non-differentiable (fractal) spacetime. The…

量子物理 · 物理学 2011-07-13 Marie-Noëlle Célérier , Laurent Nottale

Primordial nucleosynthesis remains as one of the pillars of modern cosmology. It is the testing ground upon which many cosmological models must ultimately rest. It is our only probe of the universe during the important radiation-dominated…

宇宙学与河外天体物理 · 物理学 2017-09-20 Grant J. Mathews , Motohiko Kusakabe , Toshitaka Kajino

Quasiparticles may possess not only Berry curvature but also a quantum metric in momentum space. We develop a canonical formalism for such quasiparticles based on the Dirac brackets, and demonstrate that quantum metric modifies the…

高能物理 - 理论 · 物理学 2026-05-06 Kazuya Mameda , Naoki Yamamoto

If gravitons are super-strong interacting particles and the low-temperature graviton background exists, the basic cosmological conjecture about the Dopplerian nature of redshifts may be false. In this case, a full magnitude of cosmological…

高能物理 - 理论 · 物理学 2007-05-23 Michael A. Ivanov

An Ising-type classical statistical ensemble can describe the quantum physics of fermions if one chooses a particular law for the time evolution of the probability distribution. It accounts for the time evolution of a quantum field theory…

量子物理 · 物理学 2015-06-04 C. Wetterich

The efforts in this contribution consist in reassessing a modified Dirac equation that incorporates a $\gamma^0 \gamma_5$-Lorentz-symmetry violating (LSV) term induced as a Loop Quantum Gravity (LQG) effect. Originally, this equation has…

高能物理 - 理论 · 物理学 2024-09-19 João Paulo S. Melo , Mario J. Neves , Jefferson M. A. Paixão , José A. Helayël-Neto

We explore nonlocally modified models of gravity, inspired by quantum loop corrections, as a mechanism for explaining current cosmic acceleration. These theories enjoy two major advantages: they allow a delayed response to cosmic events,…

天体物理学 · 物理学 2011-05-31 S. Deser , R. P. Woodard

When gravity is quantized, there inevitably exist quantum gravitational vacuum fluctuations which induce quadrupole moments in gravitationally polarizable objects and produce a quantum correction to the classical Newtonian interaction…

广义相对论与量子宇宙学 · 物理学 2016-11-04 Puxun Wu , Jiawei Hu , Hongwei Yu

In a previous work and in terms of an exact quantum-mechanical framework, $\hbar$-independent causal and retarded expectation values of the second-quantized electro-magnetic fields in the Coulomb gauge were derived in the presence of a…

广义相对论与量子宇宙学 · 物理学 2018-12-26 Bo-Sture K. Skagerstam , Karl-Erik Eriksson , Per K. Rekdal

Dirac particle dynamics is encoded as a unitary path summation rule and implemented on a qubit array, where the qubit array represents both spacetime and the fermions contained therein. The unitary path summation rule gives a quantum…

量子物理 · 物理学 2017-08-15 Jeffrey Yepez

In this work, we investigate Big Bang Nucleosynthesis (BBN) within the framework of $f(T,{L}_m)$ gravity, where the gravitational Lagrangian is generalized as a function of the torsion scalar $T$ and the matter Lagrangian ${L}_m$. We…

宇宙学与河外天体物理 · 物理学 2025-09-25 Daniel F. P. Cruz , David S. Pereira , Francisco S. N. Lobo , José P. Mimoso

In this article, the axioms presented in the first one are reformulated according to the special theory of relativity. Using these axioms, quantum mechanic's relativistic equations are obtained in the presence of electromagnetic fields for…

量子物理 · 物理学 2008-02-03 L. S. F. Olavo

Loop Quantum Gravity (L.Q.G.) is one of the two most promising tentative theory for a quantum description of gravity. When applied to the entire universe, the so-called Loop Quantum Cosmology (L.Q.C.) framework offers microscopical models…

广义相对论与量子宇宙学 · 物理学 2014-11-20 J. Grain

Quantum gravity corrections to the behavior of matter, such as Higgs bosons and fermions, are notoriously difficult to calculate. The standard tools of quantum field theory often break down, producing infinite results that spoil our…

综合物理 · 物理学 2025-09-22 Sebastián Alí Sacasa-Céspedes

Semiclassical gravity couples classical gravity to the quantized matter in meanfield approximation. The meanfield coupling is problematic for two reasons. First, it ignores the quantum fluctuation of matter distribution. Second, it violates…

广义相对论与量子宇宙学 · 物理学 2025-05-28 Lajos Diósi
‹ 上一页 1 8 9 10 下一页 ›