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Related papers: Why anthropic reasoning cannot predict Lambda

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The observed value of the cosmological constant corresponds to a time scale that is very close to the current conformal age of the universe. Here we show that this is not a coincidence but is caused by a periodic boundary condition, which…

General Physics · Physics 2019-09-25 Jan Stenflo

Explainability is widely regarded as essential for trustworthy artificial intelligence systems. However, the metrics commonly used to evaluate counterfactual explanations are algorithmic evaluation metrics that are rarely validated against…

Artificial Intelligence · Computer Science 2026-03-17 Felix Liedeker , Basil Ell , Philipp Cimiano , Christoph Düsing

Recent advances in string theory and inflationary cosmology have led to a surge of interest in the possible existence of an ensemble of cosmic regions, or universes, among the members of which key physical parameters, such as the masses of…

Astrophysics · Physics 2008-11-26 P. C. W. Davies

Models of open inflation with a variable density parameter $\Omega$ provide the most natural way to reconcile an open universe with inflation. The use of anthropic principle is essential to derive observational predictions of such models. I…

Astrophysics · Physics 2011-04-15 Alexander Vilenkin

We discuss how, in a Universe restricted to the causal region connected to the observer, General Relativity implies the quantum nature of physical phenomena and directly leads to a string theory scenario, whose dynamics is ruled by a…

High Energy Physics - Theory · Physics 2009-02-09 Andrea Gregori

We investigate the gravitational property of the quantum vacuum by treating its large energy density predicted by quantum field theory seriously and assuming that it does gravitate to obey the equivalence principle of general relativity. We…

General Relativity and Quantum Cosmology · Physics 2019-04-22 Qingdi Wang , Zhen Zhu , William G. Unruh

Problems with uniform probabilities on an infinite support show up in contemporary cosmology. This paper focuses on the context of inflation theory, where it complicates the assignment of a probability measure over pocket universes. The…

History and Philosophy of Physics · Physics 2023-09-11 Sylvia Wenmackers

In this year, in which we celebrate 100 years of the cosmological term, $\Lambda$, in Einstein's gravitational field equations, we are still facing the crucial question whether $\Lambda$ is truly a fundamental constant or a mildly evolving…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-27 Joan Sola , Adria Gomez-Valent , Javier de Cruz Perez

Some risks have extremely high stakes. For example, a worldwide pandemic or asteroid impact could potentially kill more than a billion people. Comfortingly, scientific calculations often put very low probabilities on the occurrence of such…

Physics and Society · Physics 2008-10-31 Toby Ord , Rafaela Hillerbrand , Anders Sandberg

The cosmological constant Lambda affects cosmological gravitational lensing. Effects due to Lambda can be studied in the framework of the Schwarzschild-de Sitter spacetime. Two novel contributions, which can not be accounted for by a proper…

Astrophysics · Physics 2009-02-23 M. Sereno

In algorithmic randomness, when one wants to define a randomness notion with respect to some non-computable measure $\lambda $, a choice needs to be made. One approach is to allow randomness tests to access the measure $\lambda $ as an…

Logic · Mathematics 2014-08-14 Bjørn Kjos-Hanssen , Antoine Taveneaux , Neil Thapen

Independent tests aiming to constrain the value of the cosmological constant $\Lambda$ are usually difficult because of its extreme smallness $\left(\Lambda \simeq 1\times 10^{-52}~\textrm{m}^{-2},~\textrm{or}~2.89\times…

General Relativity and Quantum Cosmology · Physics 2018-03-28 Lorenzo Iorio

Cosmological parameter estimation from forthcoming experiments promise to reach much greater precision than current constraints. As statistical errors shrink, the required control over systematic errors increases. Therefore, models or…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-07 José Luis Bernal , Nicola Bellomo , Alvise Raccanelli , Licia Verde

Based on a thoeretical model in which scalar fields play crucial roles, we propose a mechanism to better understand a cosmological constant expected to be small (nearly comparable with the critical density) but nonzero as suggested strongly…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yasunori Fujii

The presence of a cosmological constant, Lambda, in an action with higher powers of the curvature can produce rapidly oscillating metrics. We develop a perturbative approach for generating periodic solutions to the non-linear field…

High Energy Physics - Theory · Physics 2009-11-07 Hael Collins , Bob Holdom

I consider the relation of explanations for the observed data to testability in the following contexts: observational and experimental detection of dark matter; observational and experimental detection of dark energy or a cosmological…

Astrophysics · Physics 2015-05-13 George F. R. Ellis

The mainstream crowd counting methods regress density map and integrate it to obtain counting results. Since the density representation to one head accords to its adjacent distribution, it embeds the same category objects with variant…

Computer Vision and Pattern Recognition · Computer Science 2022-12-06 Qi Wang , Juncheng Wang , Junyu Gao , Yuan Yuan , Xuelong Li

As machine learning and algorithmic decision making systems are increasingly being leveraged in high-stakes human-in-the-loop settings, there is a pressing need to understand the rationale of their predictions. Researchers have responded to…

Machine Learning · Computer Science 2020-12-07 Jonathan Dinu , Jeffrey Bigham , J. Zico Kolter

I argue that various derivations of the Born probability rule within strictly unitary quantum mechanics implicitly use anthropic constraints on the properties of the probabilities, but without proposing an ensemble from which those…

Quantum Physics · Physics 2014-03-28 Michael B. Weissman

We provide a comprehensive discussion of the Everpresent $\Lambda$ cosmological model arising from fundamental principles in causal set theory and unimodular gravity. In this framework the value of the cosmological constant ($\Lambda$)…

General Relativity and Quantum Cosmology · Physics 2024-02-22 Santanu Das , Arad Nasiri , Yasaman K. Yazdi