This book is about the methods used for unifying different scientific theories under one all-embracing theory. The process has characterized much of the history of science and is prominent in contemporary physics; the search for a 'theory of everything' involves the same attempt at unification. Margaret Morrison argues that, contrary to popular philosophical views, unification and explanation often have little to do with each other. The mechanisms that facilitate unification are not those that enable us to explain how (...) or why phenomena behave as they do. A feature of this book is an account of many case studies of theory unification in nineteenth- and twentieth-century physics and of how evolution by natural selection and Mendelian genetics were unified into what we now term evolutionary genetics. (shrink)

Philosophers of science have long been concerned with these questions. In the 1980s, influential work by Clark Glymour, Michael Friedman, John Watkins, and Philip Kitcher articulated general accounts of theory unification that attempted to underwrite a connection between unification, truth, and understanding. According to the ‘unifiers,’ as we may call them, a theory is unified to the extent that it has a small theoretical structure relative to the domain of phenomena it covers, and there are general syntactic (...) criteria that allow one to determine how unified a theory is. The explanatory power of a theory, and the understanding of nature it gives us, is a direct consequence of this unity. As well, the more unified a theory is, the better confirmed it will be, and under some conditions a theory’s unity can justify realism about unobservable entities posited by it. In the 1990s disunity became the dominant theme, with books such as John Dupré’s The Disorder of Things and the Galison and Stump anthology arguing that it is a mistake to view science as a unified practice and that rather than an epistemic virtue, unification in science is a metaphysical vice. (shrink)

In the following, limiting ourselves to two objects—the processes X and Y—we will compare three kinds of regularities in their specific manifestation in physics: interaction; causality; and functional dependence. In considering as objective all the regularities which are inherent in things and material processes themselves, and in considering causality and functional dependence merely as one-sided abstractions of interaction, which in its turn is an abstraction from the universal interconnection of things, we avoid such an arbitrary definition of causality as, for (...) instance, the possibility of exact prognosis which leads to the negation of causality. We also avoid placing functional dependence above causality. (shrink)

A unified axiomatic theory that embraces both mechanics and thermodynamics is presented in three parts. It is based on four postulates; three are taken from quantum mechanics, and the fourth is the new disclosure of the existence of quantum states that are stable (Part I). For nonequilibrium and equilibrium states, the theory provides general original results, such as the relation between irreducible density operators and the maximum work that can be extracted adiabatically (Part IIa). For stable equilibrium (...) states, it shows for the first time that the canonical and grand canonical distributions are the only stable distributions (Part IIb). The theory discloses the incompleteness of the equation of motion of quantum mechanics not only for irreversible processes but, more significantly, for reversible processes (Part IIb). It establishes the operational meaning of an irreducible density operator and irreducible dispersions associated with any state, and reveals the relationship between such dispersions and the second law (Part III). (shrink)

There is an underlying assumption in the social sciences that consciousness and social life are ultimately classical physical/material phenomena. In this ground-breaking book, Alexander Wendt challenges this assumption by proposing that consciousness is, in fact, a macroscopic quantum mechanical phenomenon. In the first half of the book, Wendt justifies the insertion of quantum theory into social scientific debates, introduces social scientists to quantum theory and the philosophical controversy about its interpretation, and then defends the quantum consciousness hypothesis (...) against the orthodox, classical approach to the mind-body problem. In the second half, he develops the implications of this metaphysical perspective for the nature of language and the agent-structure problem in social ontology. Wendt's argument is a revolutionary development which raises fundamental questions about the nature of social life and the work of those who study it. (shrink)

Unitary field theories and “SUPER-GUT” theories work with an universal continuum, the structured spacetime of R. Descartes, B. Spinoza, B. Riemann, and A. Einstein, or a (Machian (1–3) ) structured vacuum according the quantum theory of unitary fields (Dirac, (4,5) and Heisenberg (6–8) ). The atomistic aspect of the substantial world is represented by the fundamental constants which are invariant against “all transformations” and which “depend on nothings” (Planck (9–11) ). A satisfactory unitary theory has to involve these (...) constants like the mathematical numbers. Today, Planck's conception of the three elementary constants ħ, c, and G may be the key to general relativistic quantum field theory like unitary theory. However, the elementary constants are a question of measurement-theory, also.According to Popper's theory (12–16) of induction, such unitary theories are “universal explaining theories.” The fundamental constants involve the complementarity between the universal statements in unitary theory and the “basic statements” in the language of classical observables. (shrink)

The chiralSU(3) quark model is shown to be a consequence of general relativity for Petrov type Id space-times, in much the same way that the Dirac equation is a consequence of special relativity.

This part of the paper concludes the presentation of the unified theory. It is shown that the theory requires the existence of, and applies only to, irreducible quantal dispersions associated with pure or mixed states. Two experimental procedures are given for the operational verification of such dispersions. Because the existence of irreducible dispersions associated with mixed states is required by Postulate 4 of the theory, and because Postulate 4 expresses the basic implications of the second law (...) of classical thermodynamics, it is concluded that the second law is a manifestation of phenomena characteristic of irreducible quantal dispersions associated with the elementary constituents of matter. (shrink)

Part IIb presents some of the most important theorems for stable equilibrium states that can be deduced from the four postulates of the unified theory presented in Part I. It is shown for the first time that the canonical and grand canonical distributions are the only distributions that are stable. Moreover, it is shown that reversible adiabatic processes exist which cannot be described by the dynamical equation of quantum mechanics. A number of conditions are discussed that must be (...) satisfied by the general equation of motion which is yet to be discovered. (shrink)

Part II of this three-part paper presents some of the most important theorems that can be deduced from the four postulates of the unified theory discussed in Part I. In Part IIa, it is shown that the maximum energy that can be extracted adiabatically from any system in any state is solely a function of the density operator $\hat \rho$ associated with the state. Moreover, it is shown that for any state of a system, nonequilibrium, equilibrium or stable (...) equilibrium, a unique propertyS exists which is proportional to the total energy of the system minus the maximum energy that can be extracted adiabatically from the system in combination with a reservoir. For statistically independent systems, propertyS is extensive, it is invariant during all reversible processes, and it increases during all irreversible processes. (shrink)

Evans developed a classical unified field theory of gravitation and electromagnetism on the background of a spacetime obeying a Riemann-Cartan geometry. This geometry can be characterized by an orthonormal coframe ϑ α and a (metric compatible) Lorentz connection Γ α β . These two potentials yield the field strengths torsion T α and curvature R α β . Evans tried to infuse electromagnetic properties into this geometrical framework by putting the coframe ϑ α to be proportional to four (...) extended electromagnetic potentials $\mathcal{A}^{\alpha }$ ; these are assumed to encompass the conventional Maxwellian potential A in a suitable limit. The viable Einstein-Cartan (-Sciama-Kibble) theory of gravity was adopted by Evans to describe the gravitational sector of his theory. Including also the results of an accompanying paper by Obukhov and the author, we show that Evans’ ansatz for electromagnetism is untenable beyond repair both from a geometrical as well as from a physical point of view. As a consequence, his unified theory is obsolete. (shrink)

Many physicists view the most sublime task of physics in presenting some day a world formula or a simple Theory of Everything that accounts for all major physical theories and from which everything follows by pure deduction.1 This striving for universality can look back on a long history, which contains the failed attempts to incorporate electrodynamics into universal mechanics, Einstein’s einheitliche Feldtheorie and Heisenberg’s explicit proposal of an Urgleichung. Those attempts were encouraged by the success of general relativity, (...) which embraced classical mechanics and Newtonian gravity as well defined limits. A decade later quantum mechanics was given its final shape, which allowed the explanation of all atomic phenomena known up to then and contained classical mechanics as its macroscopic limit at least in the stochastic interpretation, i.e. comparing both as theories of measurement. After the success of gauge theories in elementary particle physics, the search for a fundamental simple equation was replaced by the search for a basic symmetry group that described all fundamental interactions apart from gravity. It resulted in the famous gauge group of the Standard Model SU × SU L × U , which comprises the strong, the weak and the electromagnetic interaction. But the fact that the Standard Model contains 18 parameters, which have to be introduced from outside, inspired the search for a larger unifying gauge group. These Grand Unified Theories tried to derive some of the parameters of the Standard Model from more fundamental gauge symmetries. With the rise of string theory, which intends to include gravity as well, a new term popped up to express the old claims: Theory of Everything. (shrink)

Evans attempted to develop a classical unified field theory of gravitation and electromagnetism on the background of a spacetime obeying a Riemann-Cartan geometry. In an accompanying paper I, we analyzed this theory and summarized it in nine equations. We now propose a variational principle for a theory that implements some of the ideas that have been (imprecisely) indicated by Evans and show that it yields two field equations. The second field equation is algebraic in the torsion (...) and we can resolve it with respect to the torsion. It turns out that for all physical cases the torsion vanishes and the first field equation, together with Evans’ unified field theory, collapses to an ordinary Einstein equation. (shrink)

The author presents a history of the attempts to find the final "theory of everything," gives a forceful argument that one can never be found, and a warning that the compromises necessary to produce a final theory may well undermine the rules of doing good science. At the heart of the story is the rise of the particle physicists and their attempts to reach far out into the cosmos for a unifying theory. Unable to subject their findings (...) and theories to experimental scrutiny, they have moved into a world governed entirely by mathematical and highly speculative theories, none of which can be empirically verified. "Does physics then become a branch of aesthetics?" Lindley asks. For an opposing viewpoint, see Stephen Weinberg's Dreams of a Final Theory. Annotation copyright by Book News, Inc., Portland, OR. (shrink)

The quest for a ‘unified field theory’, which aims to integrate gravitational and electromagnetic fields into a single field structure, spanned most of Einstein’s professional life from 1919 until his death in 1955. It is seldom noted that Hans Reichenbach was possibly the only philosopher who could navigate the technical intricacies of the various unification attempts. By analyzing published writings and private correspondences, this paper aims to provide an overview of the Einstein-Reichenbach relationship from the point of view (...) of their evolving attitudes toward the program of unifying electricity and gravitation. The paper concludes that the Einstein-Reichenbach relationship is more complex than usually portrayed. Reichenbach was not only the indefatigable ‘defender’ of relativity theory but also the caustic ‘attacker’ of Einstein’s and others’ attempts at unified field theory. Over the years, Reichenbach managed to provide the first, and possibly only, overall philosophical reflection on the unified field theory program. Thereby, Reichenbach was responsible for bringing to the debate, often for the first time, some of the central issues of the philosophy of space-time physics: (a) the relation between a theory’s abstract geometrical structures (metric, affine connection) and the behavior of physical probes (rods and clocks, free particles, and so on); (b) the question of whether such association should be regarded as a geometrization of physics or a physicalization of geometry; (c) the interplay between geometrization and unification in the context of a field theory. (shrink)

In Kaluza's five-dimensional unified field theory the restriction for the 55 component of the metric tensor γ55=1 demands that the 15 equations for the unified field be weakened. Equations which have been proposed have identically vanishing trace. The equations then admit only a radiation field as source of the gravitational field. By relaxing the condition, this limitation is avoided, while retaining the striking successes of the five-dimensional approach. A scalar function, determined by the 15th field equation apart (...) from integration constants, provides source terms for both the gravitational and electromagnetic fields, in the latter case of polarization type. (shrink)

The equation for the fundamental field quantity ϱ is obtained. It is Div $\rho ^\mu (\Omega _1 ) = \operatorname{h} \int {[\rho _\mu (\Omega _1 ),\rho ^\mu (\Omega _2 )]_ - \operatorname{d} \Omega _2 } $ ,where h is an arbitrary function oft andr, and [,]− is the commutator. The derivation requires the following hypotheses:(1) All of physical reality is completely described by the field ϱ.(2) Relativistic covariance of the equations governing ϱ.(3) Principle of continguous action.(4) Conservation of total (...) amount of ϱ. The equation appears to be unique. It is suggested that the physical world corresponds to ϱ being a2×2 matrix. A close correspondence between the basic equation and Maxwell's equation is displayed. The electromagnetic vector potential Aμ is identified with ε ρμ dΩ. Conservation laws on various measures of ϱ are obtained. The symmetry groups of the basic equation are derived. A preliminary attempt to connect the field ϱ to the metric is made via Einstein's gravitational equation Gμυ =KTμυ. (shrink)

We discuss the symmetry basis of unified field theories, i.e., the generalized concept of local gauge symmetry, and its physical implications. The generalized Ward-Takahashi identities and the explicit constraints among renormalization constants are derived by using the path integral in a specific model. These constraints are confirmed at the one-loop level.

After presenting the foundation and the basic equations of a new 5-dimensional projective unified field theory, the problem of incorporating spinor fields into this framework is investigated. Apart from Pauli's method, we propose a new approach which leads to a consistent 5-dimensional spinor theory with a series of physical consequences (variability of the 4-dimensional “rest mass,” instability of 4-dimensional “stationary states,” etc.).

We discuss, within the framework provided by a recently developed variational method, transposition-invariant field equations for unified field theories. Systems that are, in addition, invariant under Weyl-type gauge transformations or lambda transformations are derived. It is found that in a weak field limit two of the systems contain the equations of general relativity and the covariant Maxwell equations for a charge-free region.

We study the magnetic monopoles in non-Abelian gauge theories. The exact static, spherically symmetric solutions of the magnetic monopoles in both Yang-Mills and unified gauge theories are obtained. The energyE of the static system is calculable and it is either zero or infinite. The existence of the magnetic monopole solution is a consequence of symmetry rather than dynamics. We propose a new definition of the electromagnetic field tensor, which relates the static solution of gauge fields and the magnetic monopole (...) solution. Experimental implications are discussed. (shrink)

This paper concerns late 1920 s attempts to construct unitary theories of gravity and electromagnetism. A first attempt using a non-standard connection—with torsion and zero-curvature—was carried out by Albert Einstein in a number of publications that appeared between 1928 and 1931. In 1929, Tullio Levi-Civita discussed Einstein’s geometric structure and deduced a new system of differential equations in a Riemannian manifold endowed with what is nowadays known as Levi-Civita connection. He attained an important result: Maxwell’s electromagnetic equations and the gravitational (...) equations were obtained exactly, while Einstein had deduced them only as a first order approximation. A main feature of Levi-Civita’s theory is the essential use of the Ricci’s rotation coefficients, introduced by Gregorio Ricci Curbastro many years before. We trace the history of Ricci’s coefficients that are still used today, and highlight their geometric and mechanical meaning. (shrink)

A mirror world consisting of matter which interacts with ordinary matter via gravity and weakly via other forces has been considered, inter alia, as a model for dark matter. A discrete symmetry under the interchange of fields means that both sectors experience the same forces. Separately it has been shown that it is possible to unify gravitation and electromagnetism by using a degenerate metric in five dimensions; in this theory there are two possible representations of charge, and there is (...) a reflection symmetry between them which, along with a gauge-like invariance, achieves the unification. Here it is shown that mirror matter arises naturally out of the degenerate theory, and as a result a new means for measuring the Brans–Dicke constant is obtained. (shrink)

Generalizing the work of Einstein and Mayer, it is assumed that at each point of space-time there exists an N-dimensional linear vector space with N≥5. This space is decomposed into a four-dimensional tangent space and an (N - 4)-dimensional internal space. On the basis of geometric considerations, one arrives at a number of fields, the field equations being derived from a variational principle. Among the fields obtained there are the electromagnetic field, Yang-Mills gauge fields, and fields that can be interpreted (...) as describing matter. As a simple example, the case N=6 is considered. (shrink)

When the fuzzy indeterminacy of quantum mechanics overthrew the orderly world of Isaac Newton, Albert Einstein and Erwin Schrödinger were at the forefront of the revolution. Neither man was ever satisfied with the standard interpretation of quantum mechanics, however, and both rebelled against what they considered the most preposterous aspect of quantum mechanics: its randomness. Einstein famously quipped that God does not play dice with the universe, and Schrödinger constructed his famous fable of a cat that was neither alive nor (...) dead not to explain quantum mechanics but to highlight the apparent absurdity of a theory gone wrong. But these two giants did more than just criticize: they fought back, seeking a Theory of Everything that would make the universe seem sensible again. In Einstein’s Dice and Schrödinger’s Cat, physicist Paul Halpern tells the little-known story of how Einstein and Schrödinger searched, first as collaborators and then as competitors, for a theory that transcended quantum weirdness. This story of their quest—which ultimately failed—provides readers with new insights into the history of physics and the lives and work of two scientists whose obsessions drove its progress. Today, much of modern physics remains focused on the search for a Theory of Everything. As Halpern explains, the recent discovery of the Higgs Boson makes the Standard Model—the closest thing we have to a unified theory— nearly complete. And while Einstein and Schrödinger failed in their attempt to explain everything in the cosmos through pure geometry, the development of string theory has, in its own quantum way, brought this idea back into vogue. As in so many things, even when they were wrong, Einstein and Schrödinger couldn’t help but get a great deal right. (shrink)

Unifying the Universe: The Physics of Heaven and Earth presents a non-technical approach to physics for the lay-science enthusiast. This popular textbook, which evolved from a conceptual course at Cornell University, is intended for non-science undergraduate students taking their first physics module. This second edition maintains its unique approach in crossing boundaries between physics and humanities, with connections to art, poetry, history, and philosophy. It explores how the process of scientific thought is inextricably linked with cultural, creative, and aesthetic aspects (...) of human endeavor, opening the readers up to new ways of looking at the world. The text has been fully updated throughout to address current and exciting new topics in the field, such as exo-planets, the accelerating Universe, dark matter, dark energy, gravitational waves, super-symmetry, string theory, big bang cosmology, and the Higgs boson. There is also an entirely new chapter on the Quantum World, which connects the fascinating topics of quantum entanglement and quantum computing. Key Features: Provides a solid, yet accessible, background to basic physics without complex mathematics Uses a human interest approach to show how science is significant for more than its technological consequences Discusses the arts and philosophies of historical periods that are pertinent to the subject. (shrink)

This paper offers a theory of quotation by uniting two apparently disparate extant theories, Recanati's pragmatic theory and Washington's identity theory. Recanati draws a distinction between open and closed quotations, and contends that open quotations do not refer. Washington argues that closed quotations refer to various expression types, not just orthographic and/or phonetic types. By combining these views, this paper proposes a theory, according to which quotations, open or closed, may be tokens of semantico-physical types (...) (i.e., meaningful expressions), and while those types are mentioned (or referred to) by closed quotations, they are used in open quotations. (shrink)

We unify three approaches within the vast body of gauge-theory research that have independently developed distinct representations of a geometrical surface-like structure underlying the vector-potential. The three approaches that we unify are: those who use the compactified dimensions of Kaluza–Klein theory, those who use Grassmannian models models) to represent gauge fields, and those who use a hidden spatial metric to replace the gauge fields. In this paper we identify a correspondence between the geometrical representations of the three schools. (...) Each school was mostly independently developed, does not compete with other schools, and attempts to isolate the gauge-invariant geometrical surface-like structures that are responsible for the resulting physics. By providing a mapping between geometrical representations, we hope physicists can now isolate representation-dependent physics from gauge-invariant physical results and share results between each school. We provide visual examples of the geometrical relationships between each school for \\) electric and magnetic fields. We highlight a first new result: in all three representations a static electric field has a hidden gauge-invariant time dependent surface that is underlying the vector potential. (shrink)

Due to its high degree of complexity and its historical nature, evolutionary biology has been traditionally portrayed as a messy science. According to the supporters of such a view, evolutionary biology would be unable to formulate laws and robust theories, instead just delivering coherent narratives and local models. In this article, our aim is to challenge this view by showing how the Price equation can work as the core of a general theoretical framework for evolutionary phenomena. To support this claim, (...) we outline some unnoticed structural similarities between physical theories and evolutionary biology. More specifically, we shall argue that the Price equation, in the same way as fundamental formalisms in physics, can serve as a heuristic principle to formulate and systematise different theories and models in evolutionary biology. (shrink)

Structured time (hyle) and its relationship to other elements of physics: matter, energy, space, etc.

The generalized Brans–Dicke theory (GBD), as one of the modified gravitational theories, was proposed previously and some interesting properties were found in this theory. Here we investigate the traversable-wormhole physics for GBD theory. Firstly, we derive the gravitational field equation in the framework of GBD wormhole geometry. The traversable wormhole could be gained in this theory. Secondly, using the classical reconstruction technique we originally derive an Lagrangian function for describing gravity in GBD theory. And the (...) derived Lagrangian function for gravity could be satisfied with the requirement of the viable conditions, such as the local gravity tests and the cosmological constraints, etc. Thus, the viable model for cosmology, local gravity and traversable WH can be unified in a uniform Lagrangian quantity within the framework of GBD theory. Thirdly, given that the violation of the energy conditions (ECs) often induce some problems in theory, we explore the ECs of matter in the traversable wormhole. It is shown that the null EC, the weak EC and the dominated EC for the matter can be satisfied in the traversable-wormhole physics of GBD theory, which are different from the results given in GR. It seems that the theory of GBD owns the more logic technically and consistency formally than the theory of GR. Fourthly, some other properties of GBD traversable WH are explored, such as the total gravitational energy, the volume integral quantifier, the dynamical stability of the anisotropic matter, and the difference of the propagation of sound within the matter configuration. The results support the GBD to provide an interesting candidate for traversable WH. (shrink)

Faith Physics maintains a sublime timeless 'Supreme Consciousness' is the catalyst of all material creation as a 'great thought' via pure white 'light' in zero-point quantum fields. In the quantum wave/particle mass duality paradigm, energy itself traveling below the speed of light becomes particulate physical matter in accord with Einstein's famous equation of E=mc2. Using the natural laws of classical physics, quantum mechanics, and the dark matter/energy that composes 95% of our known universe, a Supreme Consciousness or Godhead manifests (...) physical creation from eternal quantum fields in a remarkable myriad of forms. This is an intellectually sound and spiritually satisfying ToE. (shrink)

The Lorentz transformation is derived without assuming that the velocity of light is a constant. This suggests that the constantc which appears in the transformation has a deeper significance than heretofore commonly assumed. It is hypothesized that there exists, in all of physical reality, velocities of only one magnitude. The magnitude isc, the speed of light in vacuum. This hypothesis forces us to view a fundamental particle as an extended object and matter in general as a field ρ(t, r, (...) θ), which we give the generic name “stuff.” An important feature of the ρ field is that at each spacetime point(t, r) stuff travels in all directions θ with speedc. In order to elucidate the nature of ρ(t, r, θ), the equations determining ρ for a one-dimensional world are derived and solved. Fundamental particles are shown to exist and their structure is obtained. (shrink)