Late-time radiography at the National Ignition Facility using the Crystal Backlighter Imager (CBI) (Conference Presentation)

We propose a class of simple dark energy models which predict a late-time dark radiation component and a distinctive time-dependent equation of state w(z) for redshift z < 3. The dark energy field can be coupled strongly enough to standard model particles to be detected in colliders, and the model requires only modest additional particle content and little or no fine-tuning other than a new energy scale of order milli-electron volts.

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Observations of Hawking radiation: the Page curve and baby universes

Journal of High Energy Physics ◽

10.1007/jhep04(2021)272 ◽

2021 ◽

Vol 2021 (4) ◽

Author(s):

Donald Marolf ◽

Henry Maxfield

Keyword(s):

Black Holes ◽

Quantum Systems ◽

Late Time ◽

Asymptotically Flat ◽

Black Hole Information ◽

Flat Spacetimes ◽

The Cost ◽

Baby Universes ◽

Time Extrapolation ◽

Asymptotic Observers

AbstractWe reformulate recent insights into black hole information in a manner emphasizing operationally-defined notions of entropy, Lorentz-signature descriptions, and asymptotically flat spacetimes. With the help of replica wormholes, we find that experiments of asymptotic observers are consistent with black holes as unitary quantum systems, with density of states given by the Bekenstein-Hawking formula. However, this comes at the cost of superselection sectors associated with the state of baby universes. Spacetimes studied by Polchinski and Strominger in 1994 provide a simple illustration of the associated concepts and techniques, and we argue them to be a natural late-time extrapolation of replica wormholes. The work aims to be self-contained and, in particular, to be accessible to readers who have not yet mastered earlier formulations of the ideas above.

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Late Time Attractors of Some Varying Chaplygin Gas Cosmological Models

Symmetry ◽

10.3390/sym13050769 ◽

2021 ◽

Vol 13 (5) ◽

pp. 769

Author(s):

Martiros Khurshudyan ◽

Ratbay Myrzakulov

Keyword(s):

Dark Energy ◽

Gravitational Interaction ◽

Chaplygin Gas ◽

Cosmological Models ◽

Late Time ◽

Time Behavior ◽

Coincidence Problem ◽

Energy Models ◽

Non Linear ◽

Bayesian Machine Learning

The goal of this paper is to study new cosmological models where the dark energy is a varying Chaplygin gas. This specific dark energy model with non-linear EoS had been often discussed in modern cosmology. Contrary to previous studies, we consider new forms of non-linear non-gravitational interaction between dark matter and assumed dark energy models. We applied the phase space analysis allowing understanding the late time behavior of the models. It allows demonstrating that considered non-gravitational interactions can solve the cosmological coincidence problem. On the other hand, we applied Bayesian Machine Learning technique to learn the constraints on the free parameters. In this way, we gained a better understanding of the models providing a hint which of them can be ruled out. Moreover, the learning based on the simulated expansion rate data shows that the models cannot solve the H0 tension problem.

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ICAM-1-independent adhesion of neutrophils to phorbol ester-stimulated human airway epithelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1999.277.3.l465 ◽

1999 ◽

Vol 277 (3) ◽

pp. L465-L471 ◽

Cited By ~ 3

Author(s):

Alessandro Celi ◽

Silvana Cianchetti ◽

Stefano Petruzzelli ◽

Stefano Carnevali ◽

Filomena Baliva ◽

...

Keyword(s):

Epithelial Cells ◽

Airway Epithelial Cells ◽

Bronchial Epithelial Cells ◽

Neutrophil Adhesion ◽

Late Time ◽

Airway Epithelial ◽

Bronchial Epithelial ◽

Human Airway ◽

Stimulation Of ◽

Human Airway Epithelial Cells

Intercellular adhesion molecule-1 (ICAM-1) is the only inducible adhesion receptor for neutrophils identified in bronchial epithelial cells. We stimulated human airway epithelial cells with various agonists to evaluate whether ICAM-1-independent adhesion mechanisms could be elicited. Phorbol 12-myristate 13-acetate (PMA) stimulation of cells of the alveolar cell line A549 caused a rapid, significant increase in neutrophil adhesion from 11 ± 3 to 49 ± 7% (SE). A significant increase from 17 ± 4 to 39 ± 6% was also observed for neutrophil adhesion to PMA-stimulated human bronchial epithelial cells in primary culture. Although ICAM-1 expression was upregulated by PMA at late time points, it was not affected at 10 min when neutrophil adhesion was already clearly enhanced. Antibodies to ICAM-1 had no effect on neutrophil adhesion. In contrast, antibodies to the leukocyte integrin β-chain CD18 totally inhibited the adhesion of neutrophils to PMA-stimulated epithelial cells. These results demonstrate that PMA stimulation of human airway epithelial cells causes an increase in neutrophil adhesion that is not dependent on ICAM-1 upregulation.

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