If cosmology is to obtain knowledge about the whole universe, it faces an underdetermination problem: Alternative space-time models are compatible with our evidence. The problem can be avoided though, if there are good reasons to adopt the Cosmological Principle (CP), because, assuming the principle, one can confine oneself to the small class of homogeneous and isotropic space-time models. The aim of this paper is to ask whether there are good reasons to adopt the Cosmological Principle in order to avoid underdetermination (...) in cosmology. Various strategies to justify the CP are examined. For instance, arguments to the effect that the truth of the CP follows generically from a large set of initial conditions; an inference to the best explanation; and an inductive strategy are assessed. I conclude that a convincing justification of the CP has not yet been established, but this claim is contingent on a number of results that may have to be revised in the future. (shrink)

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.

While Karl Popper’s philosophy of science has only few followers among modern philosophers, it is easily the view of science with the biggest impact on practicing scientists. According to Peter Medawar, Nobel laureate and eminent physiologist, Popper was the greatest authority ever on the scientific method. He praised the “great strength of Karl Popper’s conception of the scientific process,” a main reason for the praise being “that it is realistic—it gives a pretty fair picture of what goes on in real (...) life laboratories” (Medawar 1990, p. 100). Either explicitly or (more often) implicitly, many scientists subscribe to some version of simplified Popperianism, usually by adopting the demarcation criterion that a .. (shrink)

If we are to constrain our place in the world, two principles are often appealed to in science. According to the Copernican Principle, we do not occupy a privileged position within the Universe. The Cosmological Principle, on the other hand, says that our observations would roughly be the same, if we were located at any other place in the Universe. In our paper we analyze these principles from a logical and philosophical point of view. We show how they are related, (...) how they can be supported and what use is made of them. Our main results are: 1. There is a logical gap between both principles insofar as the Cosmological Principle is significantly stronger than the Copernican Principle. 2. A step that is often taken for establishing the Cosmological Principle on the base of the Copernican Principle and observations is not incontestable as it stands, but can be supplemented with a different argument. 3. The Cosmological Principle might be crucial for cosmology to the extent it is not supported by empirical evidence. (shrink)

Prompted by the "Panel Discussion of Grünbaum's Philosophy of Science" (Philosophy of Science 36, December, 1969) and other recent literature, this essay ranges over major issues in the philosophy of space, time and space-time as well as over problems in the logic of ascertaining the falsity of a scientific hypothesis. The author's philosophy of geometry has recently been challenged along three main distinct lines as follows: (i) The Panel article by G. J. Massey calls for a more precise and more (...) coherent account of the Riemannian conception of an intrinsic as opposed to an extrinsic metric, which the author has invoked as his basis for the distinction between non-conventional and convention-laden ascriptions of metrical equality and inequality; (ii) the latter distinction has been claimed to suffer from the liabilities of the so-called "standard conception" of scientific theories [36]; and (iii) pursuant to H. Putnam's "An Examination of Grünbaum's Philosophy of Geometry" [56], J. Earman [16, 17] and R. Swinburne [65] have contended that the difference between intrinsic and extrinsic metrics is scientifically unilluminating, and that the associated distinction between non-conventional and convention-laden metrical comparisons does not have the kind of relevance to extant scientific theories that the author has claimed for it. The essay consists of two installments. The present installment, comprising the Introduction and Part A, is devoted to the clarification, correction and further development of the author's prior writings on the philosophy of geometry. Its main objective is constructive elaboration rather than offering polemics. But rebuttals to Earman, [16, 17], Swinburne [65] and Demopoulos [13] are included, because their inclusion conduced to clarity in giving the new exposition. Part B is to appear in a subsequent issue and will be devoted to replies to critiques contained in the Panel Discussion and in other recent literature. It will range over issues in the philosophy of geometry and in the logic of ascertaining the falsity of a scientific hypothesis. By way of merely elliptical anticipation of much more precise statements given in Part A, section 3(ii), the Introduction dissociates the notion of convention-ladenness developed in Part A from the quite different notion integral to the so-called "standard conception" of scientific theories. Thereby, the Introduction prepares the ground for seeing, as a corollary to Part A, section 3(ii), that the notion advocated in the present essay has nothing to fear from the following fact, noted by C. G. Hempel ([36]; cf. also his 1970 Carus Lectures): "even though a sentence may originally be introduced as true by stipulation, it soon joins the club of all other member-statements of the theory and becomes subject to revision in response to further empirical findings and theoretical developments." Part A, which begins with a fairly detailed table of contents, endeavors to meet the aforementioned three-fold challenge to the author's philosophy of geometry. Massey's call for the provision of clear and detailed characterizations of intrinsic and extrinsic metrics is answered with the invaluable aid rendered personally by Massey himself. These characterizations are shown to permit a precise explication of the portions of Riemann's Inaugural Dissertation relevant to (1) Riemann's brilliant anticipation of Einstein's dynamical conception of physical geometry, and (2) the author's philosophical characterization of the metrics and geometries of space, time, and space-time {section 2(c)}. A byproduct of the analysis is to raise two major philosophical doubts concerning Clifford's sketch of a so-called "space-theory of matter" as elaborated in J. A. Wheeler's relativistic geometrodynamics. That theory's vision of understanding matter as a manifestation of empty curved space is questioned in regard to (1) the existence of an intra-geometrodynamic basis for individuating the metrically homogeneous world points of its space-time manifold {section 1(a)}, and (2) the compatibility of the theory with the Riemannian metrical philosophy apparently espoused by its proponents {section 2(c)(i)}. (shrink)

In recent years, observational techniques at cosmological distances have been sufficiently improved that cosmology has become an empirical science, rather than a field for unchecked speculation. There remains the fact that its object, the whole universe, exists only once; hence, we are unable to separate “general” features from particular aspects of “our” universe. This might not be a serious drawback if we were justified in the belief that presently accepted laws of nature remain valid on the cosmological scale. In the (...) author's opinion, however, there are grounds for doubting that belief. The three arguments presented are (1) the possibility that apparent constants of nature may, during cosmological times, turn out to vary (Dirac conjecture); (2) the effective breakdown of the principle of relativity caused by the effects of the cosmological environment on local experiments; and (3) the fact that present theory leads to field singularities at the early stages of the expanding universe, which might be a signal that currently accepted theoretical concepts are inadequate for an understanding of highly condensed matter. (shrink)

Educators advocate that science education can help the development of more responsible worldviews when students learn not only scientific concepts, but also about science, or “nature of science”. Cosmology can help the formation of worldviews because this topic is embedded in socio-cultural and religious issues. Indeed, during the Cold War period, the cosmological controversy between Big Bang and Steady State theory was tied up with political and religious arguments. The present paper discusses a didactic sequence developed for and applied in (...) a pre-service science teacher-training course on history of science. After studying the historical case, pre-service science teachers discussed how to deal with possible conflicts between scientific views and students’ personal worldviews related to religion. The course focused on the study of primary and secondary sources about cosmology and religion written by cosmologists such as Georges Lemaître, Fred Hoyle and the Pope Pius XII. We used didactic strategies such as short seminars given by groups of pre-service teachers, videos, computer simulations, role-play, debates and preparation of written essays. Along the course, most pre-service teachers emphasized differences between science and religion and pointed out that they do not feel prepared to conduct classroom discussions about this topic. Discussing the relations between science and religion using the history of cosmology turned into an effective way to teach not only science concepts but also to stimulate reflections about nature of science. This topic may contribute to increasing students’ critical stance on controversial issues, without the need to explicitly defend certain positions, or disapprove students’ cultural traditions. Moreover, pre-service teachers practiced didactic strategies to deal with this kind of unusual content. (shrink)

Several variant "Newtonian" theories of inertia and gravitation are described, and their scientific usefulness discussed. An examination of these theories is used to throw light on traditional epistemological and metaphysical questions about space and time. Finally these results are examined in the light of the changes induced by the transition from "Newtonian" to general relativistic spacetime.

We discuss a number of fundamental aspects of modern cosmological concepts, from the phenomenological, observational, theoretical and epistemic points of view. We argue that the modern cosmology, despite a great advent, in particular in the observational sector, is yet to solve important problems, posed already by the classical times. In particular the stress is put on discerning the scientific features of modern cosmological paradigms from the more speculative ones, with the latter immersed in some aspects deeply into mythological world picture. (...) We finally discuss the principal paradigms, which are present in the modern cosmological studies and evaluate their epistemic merits. (shrink)

The main foundations of the standard \CDM model of cosmology are that: the redshifts of the galaxies are due to the expansion of the Universe plus peculiar motions; the cosmic microwave background radiation and its anisotropies derive from the high energy primordial Universe when matter and radiation became decoupled; the abundance pattern of the light elements is explained in terms of primordial nucleosynthesis; and the formation and evolution of galaxies can be explained only in terms of gravitation within a inflation (...) + dark matter + dark energy scenario. Numerous tests have been carried out on these ideas and, although the standard model works pretty well in fitting many observations, there are also many data that present apparent caveats to be understood with it. In this paper, I offer a review of these tests and problems, as well as some examples of alternative models. (shrink)

Inductive generalization asserts that what obtains in known instances can be generalized to all. Its original form is enumerative induction, the earliest form of inductive inference, and it has been elaborated in various ways, largely with the goal of extending its reach. Its principal problem is that it supplies no intrinsic notion of strength of support so that one cannot tell if the generalization has weak or strong support.

The present day standard cosmological model is a great theoretical achievement. This chapter surveys the main themes that have arisen and issues that are still oustanding.

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 energy (...) is violated when the time axis is terminated at t = 0. Next I discuss why this epoch (t = 0) is more a mathematical artifact whose supposed significance may disappear when one goes beyond the classical relativistic cosmology. This is illustrated by the example of quantum cosmology. (shrink)

Through an analysis of conditions under which the question of spatial anisotropy can be raised, the present paper brings out intimate conceptual relationships between the scientific concept of space and the concepts of entities, behavior, and explanation specified by scientific theories. Thus scientific departures from ordinary usage (or from usage in other scientific theories) of the term "space" entail corresponding shifts in the use of other terms not generally seen to be connected. As a case study of the relations between (...) these terms, and of the refusal to allow the possibility of spatial anisotropy, Newtonian mechanics is examined. (shrink)

This paper argues that nonphysical souls would violate fundamental physical laws if they were able to influence brain events. Though we have no idea how nonphysical souls might operate, we know quite a bit about how brains work, so we can consider each of the ways that an external force could interrupt brain processes enough to control one’s body. It concludes that there is no way that a nonphysical soul could interact with the brain—neither by introducing new energy into the (...) physical world, nor by borrowing existing energy from it—without apparently violating one or more basic laws of physics, such as the law of conservation of energy. And despite widespread appeals to quantum mechanics to give interactionism an air of scientific respectability, the essential randomness of quantum processes prohibits the distinctly nonrandom influence that a nonphysical soul must have on brain events in order to control the body, and quantum mechanical uncertainty is not great enough to allow neurons to fire action potentials. -/- 1. Introduction -- 2. How the Brain Works -- 3. Mind-Brain Interaction Mechanisms - 3.1 Opening Sodium Channels - 3.2 Altering Voltage Gradients - 3.3 Synaptic Transmission - 3.3.1 The Presynaptic Neuron - 3.3.2 The Post-Synaptic Neuron - 3.3.3 The Beck and Eccles Models - 3.4 Neuronal Modulation - 3.5 Self-Generation of Action Potentials by Neurons -- 4. Harnessing Energy -- 5. How Many Action Potentials for a Volitional Act? -- 6. Input: From Brain to Nonphysical Mind -- 7. Discussion -- Appendix A: Opening Gates on Membrane Channels - A.1 Directly Opening Gates - A.2 Changing Voltage Across the Membrane -- Appendix B: The Biochemical Approach. (shrink)

Modern standard big bang cosmology was preceded by a 15-year controversy with the rival steady-state theory of the universe. At a time when cosmologically relevant observations were scarce and cosmology was widely regarded as an immature science, or not a science at all, much of the debate took place by means of arguments that were essentially philosophical. Remarkably, professional philosophers, including some of the key figures of Anglo-American philosophy of science, took an active part in the debate; no less remarkably, (...) the involved astronomers and physicists sometimes listened to them. This article reviews the controversy over the steady-state theory as seen from the perspective of contemporary philosophy of science and offers an appraisal of how and to what extent philosophers and scientists entered a dialogue. -/- . (shrink)

The ideas of creatio ex nihilo of the universe and creatio continua of new matter out of nothing entered the arena of natural science with the advent of the Big Bang and the steady-state theories in the mid-twentieth century. Adolf Grünbaum has tried to interpret the steady-state theory in such a way, to show that the continuous formation of new matter out of nothing in this theory can be explained purely physically. In this paper, however, it will be shown that (...) Grünbaum's interpretation encounters at least three problems: not distinguishing between material and efficient causes, inconsistency, and misconceiving the law of density conservation. (shrink)

This paper derives a mathematical expression giving the development of the probability of a scientific hypothesis with the number of confirming tests, as determined by Bayes's theorem, in a special case in which all the tests are "independent" of one another. The simple expression obtained shows clearly how the various factors influence the growth of the probability. The result is used to set a numerical lower bound on the probabilities representing the a priori beliefs of humans in generalizations that become (...) accepted. By making a comparison with the predictions of a "logical atomic" model in the case of physical laws, it is argued that humans have significant a priori "knowledge" in a weak sense. (shrink)

One of the few authors to have explicitly connected the physical issue of the expansion of the universe with the philosophical topic of the metaphysical status of space is Gerald James Whitrow. This paper examines his view and tries to highlight its strong and weak points, thereby clarifying its obscure aspects. In general, this really interesting philosophical approach to one of the most important phenomena concerning our universe, and therefore modern cosmology, has been very rarely tackled. This unicity increases the (...) value, from a physical, philosophical and historical point of view, of Whitrow’s attempt and calls for new research. (shrink)

We study the possible interpretation of the "universal constants" by the classification of J.-M. Lévy-Leblond. The Planck constant and the speed of light in vacuum are the most common examples of constants of this type. Using Fock’s principle of the relativity w.r.t. observation means, we show that these two constants can be viewed as manifestations of certain relativity. We also show that there is a possibility to interpret the Boltzmann constant in a similar way, and make some comments about the (...) relativistic interpretation of the constant spacetime curvature and gravitational constant G. (shrink)

The message is that physics has an „outward bound” of scientific inquiry in the field of cosmology. I present it in the historical development. Physics and astronomy, developing since the seventeenth century, inherited from the early Greek philosophers the conception that the Universe as a whole is invariable. In nineteenth century this conception in conjunction with the conception of eternity of the Universe gave rise to contradictions with other laws of physics indicating that cosmology is not a branch of physics (...) since the notion of the Universe is not a physical one. Cosmology returned to physics as its important branch due to the advent of general relativity theory and the discovery of the cosmic microwave background radiation. Modern cosmology generates fundamental problems creating real limits to inquiries in physics viewed as an empirical science. The very notion of the Universe shows that the scientific method reaches there limits of its applicability. Does „to exist” mean „to be observed by someone”? Should the definition of the Universe be based on a current physical theory, e.g. on Einstein’s general relativity, giving rise to a kind of mathematical instability? Is the fashionable concept of the „multiverse” a physical one or is a purely metaphysical notion in a scientific disguise? If the Universe is unique, is it meaningful to describe it in the framework of physics, which by its method always assumes that the number of objects it describes, is unlimited? Apart from these permanent philosophical problems there are concrete urgent problems generated by cosmology: the nature of dark matter and dark energy. These two species of „substance” appear only in cosmology and do not fit the laboratory physics; contrary to the three centuries long tradition of modern science, now cosmology inspires physics in a troublesome way. A separate class of limits to physics is generated by the theorem in general relativity that the Universe emerged from an initial curvature singularity of the spacetime. At the singularity the whole scientific inquiry breaks down. Cosmology of the very early Universe suggests that in its evolution two specific epochs took place, that of quantum gravity and an inflationary epoch. The underlying them two physical theories are incomplete and seem to be inherently untestable. Furthermore, the experimentally verifiable physics cannot explain the origin of the initial conditions determining properties of the Universe which emerged from the singularity. (shrink)

The age of minerals determined by radioactive methods agrees roughly with the age of the galaxy. This suggests that radioactive alpha-decay constants have probably changed by less than a factor of 3 or 4 during the last 3 or 4 × l09 years. It is shown that this implies that many ‘Constants of Nature’, particularly e, h and c probably change more slowly than 10−12 parts per year. The meson coupling constant also appears to change more slowly than this and (...) the beta-coupling constants by less than 10−9 parts per year. (shrink)

We analyzed remarkable stories linked to the famous Anatoly Vlasov equations in plasma physics. Their creation, modification, and application are interesting from a scientific viewpoint. We also show the relations between those equations dealing with electromagnetism and analogous Jeans equations describing, in particular, gravitational instability in astrophysics. The second half of the essay is devoted to the controversies and political struggle in Soviet (before 1991) and Russian (after 1991) physical communities related to Vlasov’s personality, career, and posthumous recognition. The never-ending (...) destructive influence of Russian totalitarianism on science is demonstrated. (shrink)

Paths of shortest length, or geodesics, may not appear as straight lines because acceleration creates distortion. For spaces of constant curvature there are only two possibilities: Either rulers get longer as they move away from the origin or they shrink. Because the longitudinal Doppler shift corresponds to the measure of distance, in velocity space, this space is hyperbolic, corresponding to the second of the two possibilities. Transformations from one inertial frame to another are related to geometrical rigid motions. The square (...) root of the Doppler shift is related to transformations of uniformly accelerated frames. Applications to general relativity and cosmology are given including the time-velocity metric of the Friedmann universe of dust at zero pressure, Hubble's law and the exponential red-shift. (shrink)

The light clock (a photon undergoing successive reflections between two particle mirrors a fixed distance apart) has commonly been used as a theoretical confirmation of the special-relativistic slowing of clock rates. In order to obtain that result one must describe the clock photon in a system moving relatively to the clock. However, contradictory frequency transformations for the photon, as observed from the mirrors, are then predicted by relatively moving observers. A correct and consistent analysis utilizes the Lorentz-invariant relative velocity and (...) distance between the mirrors. An invariant time period is also then involved; a parallel is drawn between it and the invariance of cosmic time for internal processes in distant systems. Considering that space-time and momentum-energy are described by conjugate 4-vectors, it is conjectured that a time transformation occurs only in association with a transformation of energy. (shrink)