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相关论文: How the cosmological constant is hidden by Planck …

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Naive calculations in quantum field theory suggest that vacuum fluctuations should induce an enormous cosmological constant. What if these estimates are right? I argue that even a huge cosmological constant might be hidden in Planck scale…

广义相对论与量子宇宙学 · 物理学 2020-01-08 S. Carlip

We elaborate on the proposal of [Phys. Rev. Lett. 123 (2019) 13, 131302], about the possibility of hiding the cosmological constant in the complicated topology that one expects to exist at the Planck scale. We build a differential equation…

广义相对论与量子宇宙学 · 物理学 2020-11-25 Oliver F. Piattella

Perhaps standard effective field theory arguments are right, and vacuum fluctuations really do generate a huge cosmological constant. I show that if one does not assume homogeneity and an arrow of time at the Planck scale, a very large…

高能物理 - 理论 · 物理学 2019-10-02 S. Carlip

A recent preprint by Wang and Unruh [arXiv:1911.06110] contains a number of criticisms of my paper, "Hiding the cosmological constant" [Phys. Rev. Lett. 123 (2019) 131302, arXiv:1809.08277]. While Wang and Unruh suggest an interesting…

广义相对论与量子宇宙学 · 物理学 2019-11-27 S. Carlip

Perhaps the cosmological constant really is huge at the Planck scale, but is "hidden" by Planck scale quantum fluctuations of spacetime. I briefly review this proposal and provide some evidence, coming from a simplified midisuperspace…

广义相对论与量子宇宙学 · 物理学 2021-12-06 S. Carlip

We point out that the standard formulation of the cosmological constant problem itself is problematic since it is trying to apply the very large scale homogeneous cosmological model to very small (Planck) scale phenomenon. At small scales,…

广义相对论与量子宇宙学 · 物理学 2020-08-05 Qingdi Wang , William G. Unruh

The Planck scale is usually believed to be an unpassable wall. Putting a cutoff there and thinking of it as a quantized spacetime entity shows that. However, this is exactly the cause of many problems in quantum gravity. The cosmological…

高能物理 - 理论 · 物理学 2023-07-13 Ken-ji Hamada

We extend General Relativity by promoting Planck scale and the cosmological constant into integration constants, interpreted as fluxes of $4$-forms hiding in the theory. When we include the charges of the $4$-forms, these `constants' can…

高能物理 - 理论 · 物理学 2022-10-05 Nemanja Kaloper

The recent Planck Legacy 2018 release has confirmed the presence of an enhanced lensing amplitude in CMB power spectra compared to that predicted in the standard $\Lambda$CDM model. A closed universe can provide a physical explanation for…

宇宙学与河外天体物理 · 物理学 2019-11-07 Eleonora Di Valentino , Alessandro Melchiorri , Joseph Silk

At the level of the Planck scale, the spacetime metric has to be considered a quantum variable. Conformal quantum fluctuations of the metric tensor are studied here. They lead to an extra term in the Einstein equations which can be…

天体物理学 · 物理学 2007-05-23 Alex H. Blin

In this work we suggest a simple model of the cosmological constant as the coefficient of the quantum tunneling of vacuum fluctuations (with wave length larger than Planck length) at tiny, boundary spherical shell of the universe (with…

广义相对论与量子宇宙学 · 物理学 2009-01-06 Vladan Pankovic , Miodrag krmar , Sima Ciganovic

Within conventional big bang cosmology, it has proven to be very difficult to understand why today's cosmological constant is so small. In this paper, we show that a cyclic model of the universe can naturally incorporate a dynamical…

天体物理学 · 物理学 2009-09-01 Paul J. Steinhardt , Neil Turok

After a short history of the $\Lambda$-term it is explained why the (effective) cosmological constant is expected to obtain contributions from short-distance physics, corresponding to an energy at least as large as the Fermi scale. The…

天体物理学 · 物理学 2007-05-23 Norbert Straumann

We consider further consequences of recently [1] revealed role of cosmological constant \Lambda as of a physical constant, along with the gravitational one to define the gravity i.e. the General Relativity and its low-energy limit. We now…

综合物理 · 物理学 2019-03-13 V. G. Gurzadyan , A. Stepanian

We show that the presence of a temporal electromagnetic field on cosmological scales generates an effective cosmological constant which can account for the accelerated expansion of the universe. Primordial electromagnetic quantum…

天体物理学 · 物理学 2011-07-13 Jose Beltran Jimenez , Antonio L. Maroto

In this paper we suppose that the cosmological constant will change when the universe expends. For a general consideration, the cosmological constant is assumed to be a function of scale factor and Hubble constant. According to the ADM…

宇宙学与河外天体物理 · 物理学 2010-08-03 Jin-Zhang Tang , Qiang Xu

There appears to be no natural explanation for the cosmological constant's small size within the framework of local relativistic field theories. We argue that the recently-discussed framework for which the observable universe is identified…

高能物理 - 理论 · 物理学 2009-10-31 C. P. Burgess , R. C. Myers , F. Quevedo

We discuss how the modifications of the standard Einstein's equations needed to support the cosmological bounce can at the same time lead to vanishing of the well known cosmological constant problem, while also studying the effects of…

广义相对论与量子宇宙学 · 物理学 2025-01-24 Petar Pavlović , Marko Sossich

The current observations seem to suggest that the universe has a positive cosmological constant of the order of $H_0^2$ while the most natural value for the cosmological constant will be $L_P^{-2}$ where $L_P = (G\hbar/c^3)^{1/2}$ is the…

广义相对论与量子宇宙学 · 物理学 2009-11-07 T. Padmanabhan

We argue that the discrepancy between the Planck mass scale and the observed value of the cosmological constant can be largely attenuated if those quantities are understood as a result of effective, and thus scale-dependent, couplings. We…

广义相对论与量子宇宙学 · 物理学 2020-01-15 Felipe Canales , Benjamin Koch , Cristobal Laporte , Angel Rincon
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