中文
相关论文

相关论文: Toward fixing a framework for conformal cyclic cos…

200 篇论文

A geometric picture of conformally invariant mechanics is presented. Although the standard form of the model is recovered, the careful analysis of global geometry of phase space leads to the conclusion that, in the attractive case, the…

高能物理 - 理论 · 物理学 2011-08-18 K. Andrzejewski , J. Gonera

Universe structure emerges in the unreduced, complex-dynamical interaction process with the simplest initial configuration (two attracting homogeneous fields). The unreduced interaction analysis avoiding any perturbative model gives…

综合物理 · 物理学 2015-03-20 Andrei P. Kirilyuk

Conformal Prediction (CP) is a principled framework for quantifying uncertainty in blackbox learning models, by constructing prediction sets with finite-sample coverage guarantees. Traditional approaches rely on scalar nonconformity scores,…

机器学习 · 统计学 2025-05-07 Gauthier Thurin , Kimia Nadjahi , Claire Boyer

Motivated by the three-dimensional topological field theory / two-dimensional conformal field theory (CFT) correspondence, we study a broad class of one-dimensional quantum mechanical models, known as anyonic chains, that can give rise to…

高能物理 - 理论 · 物理学 2017-10-25 Matthew Buican , Andrey Gromov

Direction relations between extended spatial objects are important commonsense knowledge. Recently, Goyal and Egenhofer proposed a formal model, known as Cardinal Direction Calculus (CDC), for representing direction relations between…

人工智能 · 计算机科学 2010-07-01 Xiaotong Zhang , Weiming Liu , Sanjiang Li , Mingsheng Ying

For two decades the hot big-bang model has been referred to as the standard cosmology -- and for good reason. For just as long cosmologists have known that there are fundamental questions that are not addressed by the standard cosmology and…

天体物理学 · 物理学 2007-05-23 Michael S. Turner

In an undulant universe, cosmic expansion is characterized by alternating periods of acceleration and deceleration. We examine cosmologies in which the dark-energy equation of state varies periodically with the number of e-foldings of the…

天体物理学 · 物理学 2009-11-11 Gabriela Barenboim , Olga Mena Requejo , Chris Quigg

The Poincar\'e sector of a recently deformed conformal algebra is proposed to describe, after the identification of the deformation parameter with the Planck length, the symmetries of a new relativistic theory with two observer-independent…

高能物理 - 理论 · 物理学 2016-11-09 Nicola Rossano Bruno

We use cosmography to present constraints on the kinematics of the Universe without postulating any underlying theoretical model a priori. To this end, we use a Markov Chain Monte Carlo analysis to perform comparisons to the supernova Ia…

宇宙学与河外天体物理 · 物理学 2013-01-18 Alejandro Aviles , Christine Gruber , Orlando Luongo , Hernando Quevedo

Multiacceleration scenario can be used to solve the cosmological coincidence problem. In this paper, after considering the early radiation era, we revisit the cosmological dynamics of the oscillating dark energy model proposed in…

广义相对论与量子宇宙学 · 物理学 2020-10-08 S. X. Tian

The late time acceleration of the Universe has challenged contemporary cosmology since its discovery. General Relativity explains this phenomenon by introducing the cosmological constant, named the standard cosmological model…

广义相对论与量子宇宙学 · 物理学 2024-01-02 Simran Arora

A formulation of cosmology driven by fermions $\psi $ is studied. Assumption that the expectation value of the fermion bilinear is non-zero simplifies the homogeneous solution of the Dirac equations and connects the spinor field with the…

广义相对论与量子宇宙学 · 物理学 2023-06-09 David Benisty

Cosmological parameters are constrained by a wide variety of observations. We examine the concordance diagram for modern measurements of the Hubble constant, the shape parameter from large scale structure, the cluster baryon fraction, and…

宇宙学与河外天体物理 · 物理学 2024-01-22 Stacy McGaugh

We present a calculation of the angular size of the circles in the CMB predicted by Penrose on the basis of his Conformal Cyclic Cosmology. If these circles are detected, the existence of an upper limit on their angular radius would provide…

广义相对论与量子宇宙学 · 物理学 2012-10-15 Paul Tod

We argue that the Big Bang can be understood as a type of mirror. We show how reflecting boundary conditions for spinors and higher spin fields are fixed by local Lorentz and gauge symmetry, and how a temporal mirror (like the Bang) differs…

高能物理 - 唯象学 · 物理学 2022-08-23 Latham Boyle , Martin Teuscher , Neil Turok

If the fine structure constant $\alpha =e^2/(\hbar c)$ were to change, then a number of interpretations would be possible, attributing this change either to variations in the electron charge, the dielectric constant of the vacuum, the speed…

天体物理学 · 物理学 2009-10-31 John D. Barrow , Joao Magueijo

I briefly review the cosmological constant problem and the issue of dark energy (or quintessence). Within the framework of quantum field theory, the vacuum expectation value of the energy momentum tensor formally diverges as $k^4$. A cutoff…

天体物理学 · 物理学 2008-11-26 Varun Sahni

This proceeding is an introduction to cosmological applications of the Lorentz gauge theory. It provides the ingredients for a unique, though yet tentative $\Lambda$CDM theory of cosmology. The emergence of spacetime is described by the…

广义相对论与量子宇宙学 · 物理学 2023-10-18 Tomi Koivisto

The scalar-tensor theory is plagued by nagging questions if different conformal frames, in particular the Jordan and Einstein conformal frames, are equivalent to each other. As a closely related question, there are opposing views on which…

广义相对论与量子宇宙学 · 物理学 2008-11-26 Yasunori Fujii

We make the hypothesis that the velocity of light and the expansion of the universe are two aspects of one single concept connecting space and time in the expanding universe. We show that solving Friedman's equations with that…

天体物理学 · 物理学 2009-06-23 J. -M. Vigoureux , P. Vigoureux , B. Vigoureux