Lüders and Pauli proved the $\mathcal{CPT}$ theorem based on Lagrangian quantum field theory almost half a century ago. Jost gave a more general proof based on “axiomatic” field theory nearly as long ago. The axiomatic point of view has two advantages over the Lagrangian one. First, the axiomatic point of view makes clear why $\mathcal{CPT}$ is fundamental—because it is intimately related to Lorentz invariance. Secondly, the axiomatic proof gives a simple way to calculate the $\mathcal{CPT}$ transform of any relativistic field (...) without calculating $\mathcal{C}$ , $\mathcal{P}$ and $\mathcal{T}$ separately and then multiplying them. The purpose of this pedagogical paper is to “deaxiomatize” the $\mathcal{CPT}$ theorem by explaining it in a few simple steps. We use theorems of distribution theory and of several complex variables without proof to make the exposition elementary. (shrink)

Quons are particles characterized by the parameter q, which permits smooth interpolation between Bose and Fermi statistics; q = 1 gives bosons, q = -1 gives fermions. In this paper we give a heuristic argument for an extension of conservation of statistics to quons with trilinear couplings of the form ffb, where f is fermion-like and b is boson-like. We show that q f 2 = qb. In particular, we relate the bound on qγ for photons to the bound on (...) qe for electrons, allowing the very precise bound for electrons to be carried over to photons. An extension of this argument suggests that all particles are fermions or bosons to a high precision. (shrink)

This paper studies the model of the quantum electrodynamics (QED) of a single nonrelativistic electron due to W. Pauli and M. Fierz and studied further by P. Blanchard. This model exhibits infrared divergence in a very simple context. The infrared divergence is associated with the inequivalence of the Hilbert spaces associated with the free Hamiltonian and with the complete Hamiltonian. Infrared divergences that are visible in the perturbative description disappear in the space of the clothed electrons. In this model when (...) the Hamiltonian is expressed in terms of the “physical” fields that create the electron together with its cloud of soft photons, the variational principle suggested earlier can be applied. At finite time the Heisenberg field of the model acts in the space of the perturbative electron together with a finite number of perturbative photons, while the “physical” field can be chosen to act in the space of the exact (“physical”) electron eigenstates together with a finite number of physical photons. The space of the physical (or clothed) electron states can be chosen to be a Fock space. (shrink)

With his customary incisiveness, W. V. Quine presents logic as the product of two factors, truth and grammar--but argues against the doctrine that the logical ...

The paper is a response to Tadeusz Skalski's paper „The and... a Platform to Human Speech”, published in Filozofia Nauki 1/2000. Despite Skalski's claim that the essence of our controversy lies in verbal misunderstandings, I will demonstrate that I disagree with him on three issues: (i) the question of both in the context of using ethnic languages and in the context of the origin of these languages; (ii) the concept of emergence; (iii) the evaluation of naturalisation a la Searle.

A respected Harvard logician and philosopher gathers together twenty-nine writings dealing with the foundations of mathematics, Rudolf Carnap, lin-guistics, ...

Things and Their Place in Theories Our talk of external things, our very notion of things, is just a conceptual apparatus that helps us to foresee and ...

Kant's question 'How are synthetic judgments a priori possible?' pre- cipitated the Critique of Pure Reason. Question and answer notwith- standing, Mill and others persisted in doubting that such judgments were possible at all. At length some of Kant's own clearest purported.

A Christian approach to the issues that constitute bioethics is inevitable for us who cherish the truth of historic, creedal, trinitarian Christianity. Scripture teaches and the Greek and Latin Church Fathers as well as the Reformers aver that man, created in the image of God, has an inherent, if vestigial, sense of right and wrong and a conscience however marred by the fall and by rebellion. We must believe that we share this most basic ecumenism with all humanity, not because (...) of rational observation and analysis of nature, but because Scripture reveals it. We who are convinced of the truth of historic, creedal, trinitarian Christianity have a high view of Scripture and hold it to be infallible and utterly trustworthy irrespective of the importance we assign to our specific post-biblical traditional distinctives. This is a narrower but much more vital ecumenism than the first. Faithful adherence to Scripture inevitably manifests itself in remarkably similar priorities and values, often, lamentably, not because of, but in spite of, ourselves. (shrink)

Selected Logic Papers, long out of print and now reissued with eight additional essays, includes much of the author's important work on mathematical logic and ...

In 1992 M.W. Evans proposed the O(3) symmetry of electromagnetic fields by adding a constant longitudinal magnetic field to the well-known transverse electric and magnetic fields of circularly polarized plane waves, such that certain cyclic relations of a so-called O(3) symmetry are fulfilled. Since then M.W. Evans has elevated this O(3) symmetry to the status of a new law of electromagnetics. As a law of physics must be invariant under admissible coordinate transforms, namely Lorentz transforms, in 2000 he published a (...) proof of the Lorentz invariance of O(3) symmetry of electromagnetic fields. As will be shown below this proof is incorrect; more, after simple correction it will turn out here that the O(3) symmetry cannot be Lorentz invariant. (shrink)

Multilevel research strategies characterize contemporary molecular inquiry into biological systems. We outline conceptual, methodological, and explanatory dimensions of these multilevel strategies in microbial ecology, systems biology, protein research, and developmental biology. This review of emerging lines of inquiry in these fields suggests that multilevel research in molecular life sciences has significant implications for philosophical understandings of explanation, modeling, and representation.

The author proposes an analysis of boredom. The analysis he proposes is that boredom is an unpleasant mental state consisting of weariness, restlessness, and lack of interest, where certain causal relations exist among the components. He goes on to elaborate on and defend his analysis, concluding with some thoughts on the idea that boredom has some grand metaphysical significance.

Now much revised since its first appearance in 1941, this book, despite its brevity, is notable for its scope and rigor.