Results for 'The Issue of Vacuum Energy and Cosmological Constant'

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  1.  58
    Vacuum Energy as the Origin of the Gravitational Constant.Durmuş A. Demir - 2009 - Foundations of Physics 39 (12):1407-1425.
    We develop a geometro-dynamical approach to the cosmological constant problem (CCP) by invoking a geometry induced by the energy-momentum tensor of vacuum, matter and radiation. The construction, which utilizes the dual role of the metric tensor that it structures both the spacetime manifold and energy-momentum tensor of the vacuum, gives rise to a framework in which the vacuum energy induced by matter and radiation, instead of gravitating, facilitates the generation of the gravitational (...)
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  2.  8
    About the Measure of the Bare Cosmological Constant.Massimo Cerdonio - 2019 - Foundations of Physics 49 (8):830-836.
    I try to revive, and possibly reconcile, a debate started a few years ago, about the relative roles of a bare cosmological constant and of a vacuum energy, by taking the attitude to try to get the most from the physics now available as established. I notice that the bare cosmological constant of the Einstein equations, which is there ever since GR emerged, is actually constrained (if not measured) indirectly combining the effective cosmological (...)
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  3.  23
    The Hierarchy Problem and the Cosmological Constant Problem Revisited.Fred Jegerlehner - 2019 - Foundations of Physics 49 (9):915-971.
    We argue that the Standard Model in the Higgs phase does not suffer from a “hierarchy problem” and that similarly the “cosmological constant problem” resolves itself if we understand the SM as a low energy effective theory emerging from a cutoff-medium at the Planck scale. We actually take serious Veltman’s “The Infrared–Ultraviolet Connection” addressing the issue of quadratic divergences and the related huge radiative correction predicted by the SM in the relationship between the bare and the (...)
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  4.  67
    The Role of Energy Conservation and Vacuum Energy in the Evolution of the Universe.Jan M. Greben - 2010 - Foundations of Science 15 (2):153-176.
    We discuss a new theory of the universe in which the vacuum energy is of classical origin and dominates the energy content of the universe. As usual, the Einstein equations determine the metric of the universe. However, the scale factor is controlled by total energy conservation in contrast to the practice in the Robertson–Walker formulation. This theory naturally leads to an explanation for the Big Bang and is not plagued by the horizon and cosmological (...) problem. It naturally accommodates the notion of dark energy and proposes a possible explanation for dark matter. It leads to a dual description of the universe, which is reminiscent of the dual theory proposed by Milne in 1937. On the one hand one can describe the universe in terms of the original Einstein coordinates in which the universe is expanding, on the other hand one can describe it in terms of co-moving coordinates which feature in measurements. In the latter representation the universe looks stationary and the age of the universe appears constant. The paper describes the evolution of this universe. It starts out in a classical state with perfect symmetry and zero entropy. Due to the vacuum metric the effective energy density is infinite at the beginning, but diminishes rapidly. Once it reaches the Planck energy density of elementary particles, the formation of particles can commence. Because of the quantum nature of creation and annihilation processes spatial and temporal inhomogeneities appear in the matter distributions, resulting in residual proton (neutron) and electron densities. Hence, quantum uncertainty plays an essential role in the creation of a diversified complex universe with increasing entropy. It thus seems that quantum fluctuations play a role in cosmology similar to that of random mutations in biology. Other analogies to biological principles, such as recapitulation, are also discussed. (shrink)
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  5.  57
    The quantum vacuum and the cosmological constant problem.Svend E. Rugh & Henrik Zinkernagel - 2002 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 33 (4):663-705.
    The cosmological constant problem arises at the intersection between general relativity and quantum field theory, and is regarded as a fundamental problem in modern physics. In this paper we describe the historical and conceptual origin of the cosmological constant problem which is intimately connected to the vacuum concept in quantum field theory. We critically discuss how the problem rests on the notion of physically real vacuum energy, and which relations between general relativity and (...)
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  6. On Dark Energy, Weyl’s Geometry, Different Derivations of the Vacuum Energy Density and the Pioneer Anomaly.Carlos Castro - 2007 - Foundations of Physics 37 (3):366-409.
    Two different derivations of the observed vacuum energy density are presented. One is based on a class of proper and novel generalizations of the de Sitter solutions in terms of a family of radial functions R that provides an explicit formula for the cosmological constant along with a natural explanation of the ultraviolet/infrared entanglement required to solve this problem. A nonvanishing value of the vacuum energy density of the order of ${10^{- 123} M_{\rm Planck}^4}$ (...)
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  7. The quantum vacuum and the cosmological constant problem.E. S. & H. Zinkernagel - 2002 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 33 (4):663-705.
    The cosmological constant problem arises at the intersection between general relativity and quantum field theory, and is regarded as a fundamental problem in modern physics. In this paper, we describe the historical and conceptual origin of the cosmological constant problem which is intimately connected to the vacuum concept in quantum field theory. We critically discuss how the problem rests on the notion of physically real vacuum energy, and which relations between general relativity and (...)
     
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  8.  31
    TTOM in action: Refining the variational approach to cognition and culture.Samuel P. L. Veissière, Axel Constant, Maxwell J. D. Ramstead, Karl J. Friston & Laurence J. Kirmayer - 2020 - Behavioral and Brain Sciences 43:e120.
    The target article “Thinking Through Other Minds” (TTOM) offered an account of the distinctively human capacity to acquire cultural knowledge, norms, and practices. To this end, we leveraged recent ideas from theoretical neurobiology to understand the human mind in social and cultural contexts. Our aim was bothsynthetic– building an integrative model adequate to account for key features of cultural learning and adaptation; andprescriptive– showing how the tools developed to explain brain dynamics can be applied to the emergence of social and (...)
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  9.  43
    What Can the Quantum Liquid Say on the Brane Black Hole, the Entropy of an Extremal Black Hole, and the Vacuum Energy?G. E. Volovik - 2003 - Foundations of Physics 33 (2):349-368.
    Using quantum liquids one can simulate the behavior of the quantum vacuum in the presence of the event horizon. The condensed matter analogs demonstrate that in most cases the quantum vacuum resists formation of the horizon, and even if the horizon is formed different types of the vacuum instability develop, which are faster than the process of Hawking radiation. Nevertheless, it is possible to create the horizon on the quantum-liquid analog of the brane, where the vacuum (...)
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  10.  74
    Problems with the cosmological constant problem.Adam Koberinski - 2021 - In Christian Wüthrich, Baptiste Le Bihan & Nick Huggett (eds.), Philosophy Beyond Spacetime. Oxford University Press.
    The cosmological constant problem is widely viewed as an important barrier and hint to merging quantum field theory and general relativity. It is a barrier insofar as it remains unsolved, and a solution may hint at a fuller theory of quantum gravity. I critically examine the arguments used to pose the cosmological constant problem, and find many of the steps poorly justified. In particular, there is little reason to accept an absolute zero point energy scale (...)
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  11.  86
    Multiscale integration: beyond internalism and externalism.Maxwell J. D. Ramstead, Michael D. Kirchhoff, Axel Constant & Karl J. Friston - 2019 - Synthese 198 (Suppl 1):41-70.
    We present a multiscale integrationist interpretation of the boundaries of cognitive systems, using the Markov blanket formalism of the variational free energy principle. This interpretation is intended as a corrective for the philosophical debate over internalist and externalist interpretations of cognitive boundaries; we stake out a compromise position. We first survey key principles of new radical views of cognition. We then describe an internalist interpretation premised on the Markov blanket formalism. Having reviewed these accounts, we develop our positive multiscale (...)
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  12.  16
    Regularizing (Away) Vacuum Energy.Adam Koberinski - 2021 - Foundations of Physics 51 (1):1-22.
    In this paper I formulate Minimal Requirements for Candidate Predictions in quantum field theories, inspired by viewing the standard model as an effective field theory. I then survey standard effective field theory regularization procedures, to see if the vacuum expectation value of energy density ) is a quantity that meets these requirements. The verdict is negative, leading to the conclusion that \ is not a physically significant quantity in the standard model. Rigorous extensions of flat space quantum field (...)
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  13.  35
    Quantum Mechanics, Formalization and the Cosmological Constant Problem.Jerzy Król & Torsten Asselmeyer-Maluga - 2020 - Foundations of Science 25 (4):879-904.
    Based on formal arguments from Zermelo–Fraenkel set theory we develop the environment for explaining and resolving certain fundamental problems in physics. By these formal tools we show that any quantum system defined by an infinite dimensional Hilbert space of states interferes with the spacetime structure M. M and the quantum system both gain additional degrees of freedom, given by models of Zermelo–Fraenkel set theory. In particular, M develops the ground state where classical gravity vanishes. Quantum mechanics distinguishes set-theoretic random forcing (...)
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  14.  19
    Unimodular quantum gravity and the cosmological constant.R. Percacci - 2018 - Foundations of Physics 48 (10):1364-1379.
    It is shown that the one-loop effective action of unimodular gravity is the same as that of ordinary gravity, restricted to unimodular metrics. The only difference is in the treatment of the global scale degree of freedom and of the cosmological term. A constant vacuum energy does not gravitate, addressing one aspect of the cosmological constant problem.
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  15.  12
    Preludes to dark energy: zero-point energy and vacuum speculations.Helge Kragh - 2012 - Archive for History of Exact Sciences 66 (3):199-240.
    According to modern physics and cosmology, the universe expands at an increasing rate as the result of a “dark energy” that characterizes empty space. Although dark energy is a modern concept, some elements in it can be traced back to the early part of the twentieth century. I examine the origin of the idea of zero-point energy, and in particular how it appeared in a cosmological context in a hypothesis proposed by Walther Nernst in 1916. The (...)
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  16.  16
    A Non-perturbative Hamiltonian Approach to the Cosmological Constant Problem.Syed Moeez Hassan - 2019 - Foundations of Physics 49 (5):391-427.
    It was recently suggested that the cosmological constant problem as viewed in a non-perturbative framework is intimately connected to the choice of time and a physical Hamiltonian. We develop this idea further by calculating the non-perturbative vacuum energy density as a function of the cosmological constant with multiple choices of time. We also include a spatial curvature of the universe and generalize this calculation beyond cosmology at a classical level. We show that vacuum (...)
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  17.  89
    The free energy principle: it’s not about what it takes, it’s about what took you there.Axel Constant - 2021 - Biology and Philosophy 36 (2):1-17.
    Philosophical writings on the free energy principle in the life sciences often give the impression that minimising free energy is sufficient for life. But minimising free energy is not a sufficient condition for life. In fact, one can perfectly well conceive of a system that actively minimises its free energy, and for this very reason moves inexorably towards death. So, where does the assumption of this entailment relation come from? There is indeed an entailment relation, but (...)
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  18.  30
    On Vacuum Fluctuations and Particle Masses.M. D. Pollock - 2012 - Foundations of Physics 42 (10):1300-1328.
    The idea that the mass m of an elementary particle is explained in the semi-classical approximation by quantum-mechanical zero-point vacuum fluctuations has been applied previously to spin-1/2 fermions to yield a real and positive constant value for m, expressed through the spinorial connection Γ i in the curved-space Dirac equation for the wave function ψ due to Fock. This conjecture is extended here to bosonic particles of spin 0 and spin 1, starting from the basic assumption that all (...)
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  19. Beyond ostension: Introducing the expressive principle of relevance.Constant Bonard - 2022 - Journal of Pragmatics 187:13-23.
    In this paper, I am going to cast doubt on an idea that is shared, explicitly or implicitly, by most contemporary pragmatic theories: that the inferential interpretation procedure described by Grice, neo-Griceans, or post-Griceans applies only to the interpretation of ostensive stimuli. For this special issue, I will concentrate on the relevance theory (RT) version of this idea. I will proceed by putting forward a dilemma for RT and argue that the best way out of it is to accept (...)
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  20.  4
    The Cosmological Constant From Planckian Fluctuations and the Averaging Procedure.S. Viaggiu - 2019 - Foundations of Physics 49 (11):1287-1305.
    In this paper I continue the investigation in Viaggiu, Viaggiu concerning my proposal on the nature of the cosmological constant. In particular, I study both mathematically and physically the quantum Planckian context and I provide, in order to depict quantum fluctuations and in absence of a complete quantum gravity theory, a semiclassical solution where an effective inhomogeneous metric at Planckian scales or above is averaged. In such a framework, a generalization of the well known Buchert formalism is obtained (...)
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  21. a variational approach to niche construction.Axel Constant, Maxwell Ramstead, Samuel Veissière, John Campbell & Karl Friston - 2018 - Journals of the Royal Society Interface 15:1-14.
    In evolutionary biology, niche construction is sometimes described as a genuine evolutionary process whereby organisms, through their activities and regulatory mechanisms, modify their environment such as to steer their own evolutionary trajectory, and that of other species. There is ongoing debate, however, on the extent to which niche construction ought to be considered a bona fide evolutionary force, on a par with natural selection. Recent formulations of the variational free-energy principle as applied to the life sciences describe the properties (...)
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  22.  52
    Bernard of Clairvaux, Peter Abelard and Heloise on the Definition of Love.Constant J. Mews - 2004 - Revista Portuguesa de Filosofia 60 (3):633 - 660.
    This paper examines the thinking of Bernard of Clairvaux about love in relationship to the ideas of his two famous contemporaries, Peter Abelard and Héloise. It looks at Bernard's intellectual debt to William of Champeaux on issues of sin and grace, and to William of Saint-Thierry for ideas about how amor evolves into caritas. Bernard makes a stronger link between amor and dilectio, and introduces use of the Song of Songs, to explain how worldly love can develop into spiritual love. (...)
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  23.  59
    Inducing the Cosmological Constant from Five-Dimensional Weyl Space.José Edgar Madriz Aguilar & Carlos Romero - 2009 - Foundations of Physics 39 (11):1205-1216.
    We investigate the possibility of inducing the cosmological constant from extra dimensions by embedding our four-dimensional Riemannian space-time into a five-dimensional Weyl integrable space. Following the approach of the space-time-matter theory we show that when we go down from five to four dimensions, the Weyl field may contribute both to the induced energy-tensor as well as to the cosmological constant Λ, or more generally, it may generate a time-dependent cosmological parameter Λ(t). As an application, (...)
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  24.  16
    Between authenticity and interpretation on the letter collection of Peter Abelard and heloise and the epistolae duorum amantium.Constant J. Mews - 2014 - Tijdschrift Voor Filosofie 76 (4):823-842.
    This article reviews the recent edition by David Luscombe, accompanied by an English translation of The Letter Collection of Abelard and Heloise. In particular it considers Luscombe’s claim that the exchange begins with quarrelling about love, but concludes with shared reflection on religious life. It examines the unity of the letter collection as preserved in manuscripts, with particular attention to the way it is often reproduced, as in this volume, without the final text, the Institutiones nostre, which sets out the (...)
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  25. A Multi-scale View of the Emergent Complexity of Life: A Free-energy Proposal.Casper Hesp, Maxwell Ramstead, Axel Constant, Paul Badcock, Michael David Kirchhoff & Karl Friston - forthcoming - In Michael Price & John Campbell (eds.), Evolution, Development, and Complexity: Multiscale Models in Complex Adaptive Systems.
    We review some of the main implications of the free-energy principle (FEP) for the study of the self-organization of living systems – and how the FEP can help us to understand (and model) biotic self-organization across the many temporal and spatial scales over which life exists. In order to maintain its integrity as a bounded system, any biological system - from single cells to complex organisms and societies - has to limit the disorder or dispersion (i.e., the long-run entropy) (...)
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  26. Gauge symmetry and the Theta vacuum.Richard Healey - 2009 - In Mauricio Suárez, Mauro Dorato & Miklós Rédei (eds.), EPSA Philosophical Issues in the Sciences · Launch of the European Philosophy of Science Association. Dordrecht, Netherland: Springer. pp. 105--116.
    According to conventional wisdom, local gauge symmetry is not a symmetry of nature, but an artifact of how our theories represent nature. But a study of the so-called theta-vacuum appears to refute this view. The ground state of a quantized non-Abelian Yang-Mills gauge theory is characterized by a real-valued, dimensionless parameter theta—a fundamental new constant of nature. The structure of this vacuum state is often said to arise from a degeneracy of the vacuum of the corresponding (...)
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  27. Mad Speculation and Absolute Inhumanism: Lovecraft, Ligotti, and the Weirding of Philosophy.Ben Woodard - 2011 - Continent 1 (1):3-13.
    continent. 1.1 : 3-13. / 0/ – Introduction I want to propose, as a trajectory into the philosophically weird, an absurd theoretical claim and pursue it, or perhaps more accurately, construct it as I point to it, collecting the ground work behind me like the Perpetual Train from China Mieville's Iron Council which puts down track as it moves reclaiming it along the way. The strange trajectory is the following: Kant's critical philosophy and much of continental philosophy which has followed, (...)
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  28.  67
    The Tensors of the Averaged Relative Energy–Momentum and Angular Momentum in General Relativity and Some of Their Applications.Janusz Garecki - 2007 - Foundations of Physics 37 (3):341-365.
    There exist different kinds of averaging of the differences of the energy–momentum and angular momentum in normal coordinates NC(P) which give tensorial quantities. The obtained averaged quantities are equivalent mathematically because they differ only by constant scalar dimensional factors. One of these averaging was used in our papers [J. Garecki, Rep. Math. Phys. 33, 57 (1993); Int. J. Theor. Phys. 35, 2195 (1996); Rep. Math. Phys. 40, 485 (1997); J. Math. Phys. 40, 4035 (1999); Rep. Math. Phys. 43, (...)
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  29.  25
    What represents space-time? And what follows for substantivalism vs. relationalism and gravitational energy?J. Brian Pitts - 2022 - In Antonio Vassallo (ed.), The Foundations of Spacetime Physics: Philosophical Perspectives. New York, NY: Routledge.
    The questions of what represents space-time in GR, the status of gravitational energy, the substantivalist-relationalist issue, and the exceptional status of gravity are interrelated. If space-time has energy-momentum, then space-time is substantival. Two extant ways to avoid the substantivalist conclusion deny that the energy-bearing metric is part of space-time or deny that gravitational energy exists. Feynman linked doubts about gravitational energy to GR-exceptionalism, as do Curiel and Duerr; particle physics egalitarianism encourages realism about gravitational (...)
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  30. The energy of the Universe.F. I. Cooperstock & M. Israelit - 1995 - Foundations of Physics 25 (4):631-635.
    References to energy of the universe have focussed upon the matter contribution, whereas the conservation laws must include a gravitational contribution as well. The conservation laws as applied to FRW cosmologies suggest a zero total energy irrespective of the spatial curvature when the value of the cosmological constant is taken to be zero. This result provides a useful constraint on models of the early universe and lends support to currently studied theories of the universe arising as (...)
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  31. The concepts of "beginning" and "creation" in cosmology.Jayant V. Narlikar - 1992 - Philosophy of Science 59 (3):361-371.
    The paper is inspired by the arguments raised recently by Grunbaum criticizing the current approaches of many cosmologists to the problem of spacetime singularity, matter creation and the origin of the universe. While agreeing with him that the currently favored cosmological ideas do not indicate the biblical notion of divine creation ex nihilo, I present my viewpoint on the same issues, which differs considerably from Grunbaum's. First I show that the symmetry principle which leads to the conservation law of (...)
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  32.  14
    Symplectic Quantization II: Dynamics of Space–Time Quantum Fluctuations and the Cosmological Constant.Giacomo Gradenigo - 2021 - Foundations of Physics 51 (3):1-18.
    The symplectic quantization scheme proposed for matter scalar fields in the companion paper (Gradenigo and Livi, arXiv:2101.02125, 2021) is generalized here to the case of space–time quantum fluctuations. That is, we present a new formalism to frame the quantum gravity problem. Inspired by the stochastic quantization approach to gravity, symplectic quantization considers an explicit dependence of the metric tensor gμν\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$g_{\mu \nu }$$\end{document} on an additional time variable, named intrinsic time at variance (...)
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  33.  86
    Thinking through other minds: A variational approach to cognition and culture.Samuel P. L. Veissière, Axel Constant, Maxwell J. D. Ramstead, Karl J. Friston & Laurence J. Kirmayer - 2020 - Behavioral and Brain Sciences 43:e90.
    The processes underwriting the acquisition of culture remain unclear. How are shared habits, norms, and expectations learned and maintained with precision and reliability across large-scale sociocultural ensembles? Is there a unifying account of the mechanisms involved in the acquisition of culture? Notions such as “shared expectations,” the “selective patterning of attention and behaviour,” “cultural evolution,” “cultural inheritance,” and “implicit learning” are the main candidates to underpin a unifying account of cognition and the acquisition of culture; however, their interactions require greater (...)
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  34. Quantum vacuum noise in physics and cosmology.Paul Davies - manuscript
    The concept of the vacuum in quantum field theory is a subtle one. Vacuum states have a rich and complex set of properties that produce distinctive, though usually exceedingly small, physical effects. Quantum vacuum noise is familiar in optical and electronic devices, but in this paper I wish to consider extending the discussion to systems in which gravitation, or large accelerations, are important. This leads to the prediction of vacuum friction: The quantum vacuum can act (...)
     
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  35. The Dirac large number hypothesis and a system of evolving fundamental constants.Andrew Holster - manuscript
    In his [1937, 1938], Paul Dirac proposed his “Large Number Hypothesis” (LNH), as a speculative law, based upon what we will call the “Large Number Coincidences” (LNC’s), which are essentially “coincidences” in the ratios of about six large dimensionless numbers in physics. Dirac’s LNH postulates that these numerical coincidences reflect a deeper set of law-like relations, pointing to a revolutionary theory of cosmology. This led to substantial work, including the development of Dirac’s later [1969/74] cosmology, and other alternative cosmologies, such (...)
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  36.  68
    The Extended Relativity Theory in Born-Clifford Phase Spaces with a Lower and Upper Length Scales and Clifford Group Geometric Unification.Carlos Castro - 2005 - Foundations of Physics 35 (6):971-1041.
    We construct the Extended Relativity Theory in Born-Clifford-Phase spaces with an upper R and lower length λ scales (infrared/ultraviolet cutoff). The invariance symmetry leads naturally to the real Clifford algebra Cl (2, 6, R) and complexified Clifford Cl C (4) algebra related to Twistors. A unified theory of all Noncommutative branes in Clifford-spaces is developed based on the Moyal-Yang star product deformation quantization whose deformation parameter involves the lower/upper scale $$(\hbar \lambda / R)$$. Previous work led us to show from (...)
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  37. The Metaphysics of Emptiness "La Métaphysique de la Vacuité".Richard Healey - 1998 - In E. Gunzig & S. Diner (eds.), Le Vide: Univers du Tout Et du Rien, Eds. E. Gunzig and S. Diner, Revue de L’Université de Bruxelles. Éditions Complexe, 1998. Revue de L’Université de Bruxelles. Éditions Complexe,.
    Is there a vacuum in nature? This is a question which preoccupied natural philosophers for millennia. Great thinkers including Democritus and Newton maintained the existence of a vacuum, while Aristotle, Descartes and Leibniz argued strongly that there was not, and perhaps could not be, any such thing. A casual glance at the literature of contemporary physics may leave the impression that scientific progress has produced a definitive positive answer, so that the philosophers' debates are now of only historical (...)
     
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  38. The Pseudo-Problem of Creation in Physical Cosmology.Adolf Grünbaum - 1989 - Philosophy of Science 56 (3):373 - 394.
    According to some cosmologists, the big bang cosmogony and even the (now largely defunct) steady-state theory pose a scientifically insoluble problem of matter-energy creation. But I argue that the genuine problem of the origin of matter-energy or of the universe has been fallaciously transmuted into the pseudo-problem of creation by an external cause. A fortiori, it emerges that the initial "true" and "false" vacuum states of quantum cosmology do not vindicate biblical divine creation ex nihilo at all.
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  39.  28
    Are Dark Energy and Dark Matter Different Aspects of the Same Physical Process?Ruth Kastner & Stuart Kauffman - unknown
    It is suggested that the apparently disparate cosmological phenomena attributed to so-called ‘dark matter’ and ‘dark energy’ arise from the same fundamental physical process: the emergence, from the quantum level, of spacetime itself. This creation of spacetime results in metric expansion around mass points in addition to the usual curvature due to stress-energy sources of the gravitational field. A recent modification of Einstein’s theory of general relativity by Chadwick, Hodgkinson, and McDonald incorporating spacetime expansion around mass points, (...)
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  40.  31
    Comments on the Papers of Cushing and Redhead: "Models, High-Energy Theoretical Physics and Realism" and "Quantum Field Theory for Philosophers".Paul Teller - 1982 - PSA: Proceedings of the Biennial Meeting of the Philosophy of Science Association 1982:100 - 111.
    In response to Cushing it is urged that the vicissitudes of quantum field theory do not press towards a nonrealist attitude towards the theory as strongly as he suggests. A variety of issues which Redhead raises are taken up, including photon localizability, the wave-particle distinction in the classical limit, and the interpretation of quantum statistics, vacuum fluctuations, virtual particles, and creation and annihilation operators. It is urged that quantum field theory harbors an unacknowledged inconsistency connected with the fact that (...)
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  41.  18
    Healing the Body Politic: the political thought of Christine de Pizan.Karen Green & Constant Mews (eds.) - 2005 - Turnhout: Brepols.
    The essays in this collection focus on Christine as a political writer and provide an important resource for those wishing to understand her political thought. They locate her political writing in the late medieval tradition, discussing her indebtedness to Aristotle, Aquinas and Augustine as well as her transformations of their thought. They also illuminate Christines political epistemology her understanding of political wisdom as a part of theology, the knowledge of God. New light is thrown on the circumstances which prompted Christine (...)
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  42. Detection of negative energy: 4-dimensional examples.Paul Davies - manuscript
    We study the response of switched particle detectors to static negative energy densities and negative energy fluxes. It is demonstrated how the switching leads to excitation even in the vacuum and how negative energy can lead to a suppression of this excitation. We obtain quantum inequalities on the detection similar to those obtained for the energy density by Ford and co-workers and in an ‘‘operational’’ context by Helfer. We reexamine the question ‘‘Is there a quantum (...)
     
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  43.  15
    Sergei Vsekhsvyatskii’s Studies on Philosophical Issues of Cosmology and Cosmogony.Sergii Rudenko & Yaroslav Sobolievskyi - 2022 - Философия И Космология 28:146-158.
    This paper analyses the methodological ideas of Sergei Vsekhsvyatskii’s Studies on Philosophical Issues of Cosmology and Cosmogony. The article examines the background and history of the development of astronomy and cosmology in Ukraine and its gradual transition from a descriptive method to mathematical analysis. The authors have studied the influence of Ukrainian scholars and philosophers on studies in cosmology, astronomy, philosophical issues in cosmology, and computational cosmology. The philosophical understanding of cosmology and cosmogony is always a search for alternative views (...)
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  44.  21
    Our Runaway Universe and Einstein's Cosmological Constant.John Cramer - unknown
    Much of what you thought you knew about the universe and its expansion may be wrong. That expansion appears to be speeding up rather than slowing E = mc 2). down. This column is about recent astronomical evidence for a positive cosmological constant, suggesting that space itself has mass-energy..
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  45.  16
    Formalizing the Dynamics of Information.Martina Faller, Stefan C. Kaufmann, Marc Pauly & Center for the Study of Language and Information S.) - 2000 - Center for the Study of Language and Information Publications.
    The papers collected in this volume exemplify some of the trends in current approaches to logic, language and computation. Written by authors with varied academic backgrounds, the contributions are intended for an interdisciplinary audience. The first part of this volume addresses issues relevant for multi-agent systems: reasoning with incomplete information, reasoning about knowledge and beliefs, and reasoning about games. Proofs as formal objects form the subject of Part II. Topics covered include: contributions on logical frameworks, linear logic, and different approaches (...)
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  46.  5
    An Anatomic and Physiologic Analysis of the Discussions on the Locus of Human Power among the Schools of Kalām.C. A. N. Seyithan - 2021 - Kader 19 (2):631-644.
    The issue of power has been addressed as part of human actions, which form the basis of the discussions of destiny in Islamic theology. Various schools of kalām have extensively discussed the issue of power throughout history. The locus of power is also one of the critical concerns that have been emphasized within these discussions. The schools of the Mu'tazila, al-Ashʿarī and al-Māturīdī have put forward different perspectives on whether the locus of power exists or not and where (...)
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  47. The cosmological constant, the fate of the universe, unimodular gravity, and all that.John Earman - 2003 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 34 (4):559-577.
    The cosmological constant is back. Several lines of evidence point to the conclusion that either there is a positive cosmological constant or else the universe is filled with a strange form of matter (“quintessence”) that mimics some of the effects of a positive lambda. This paper investigates the implications of the former possibility. Two senses in which the cosmological constant can be a constant are distinguished: the capital Λ sense in which lambda is (...)
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  48. Reflections on the Reversibility of Nuclear Energy Technologies.Jan Peter Bergen - 2017 - Dissertation, Delft University of Technology
    The development of nuclear energy technologies in the second half of the 20th century came with great hopes of rebuilding nations recovering from the devasta-tion of the Second World War or recently released from colonial rule. In coun-tries like France, India, the USA, Canada, Russia, and the United Kingdom, nuclear energy became the symbol of development towards a modern and technologically advanced future. However, after more than six decades of experi-ence with nuclear energy production, and in the (...)
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  49.  13
    Ethics, The Social Sciences, and Policy Analysis.Daniel Callahan, Sidney Callahan, Bruce Jennings & Director of Bioethics Bruce Jennings - 1983 - Springer.
    The social sciences playa variety of multifaceted roles in the policymaking process. So varied are these roles, indeed, that it is futile to talk in the singular about the use of social science in policymaking, as if there were one constant relationship between two fixed and stable entities. Instead, to address this issue sensibly one must talk in the plural about uses of dif ferent modes of social scientific inquiry for different kinds of policies under various circumstances. In (...)
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  50.  25
    Scientific Controversies: Case Studies in the Resolution and Closure of Disputes in Science and Technology.Hugo Tristram Engelhardt, H. Tristram Engelhardt Jr, Arthur L. Caplan & Drs William F. And Virginia Connolly Mitty Chair Arthur L. Caplan - 1987 - Cambridge University Press.
    This collection of essays examines the ways in which disputes and controversies about the application of scientific knowledge are resolved. Four concrete examples of public controversy are considered in detail: the efficacy of Laetrile, the classification of homosexuality as a disease, the setting of safety standards in the workplace, and the utility of nuclear energy as a source of power. The essays in this volume show that debates about these cases are not confined to matters of empirical fact. Rather, (...)
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