Anforderungen an eine physikalische Fundamentaltheorie

Requirements for a Fundamental Physical Theory. The search for a so-called ‘Theory of Everything’ which should lead to the unification of all fundamental forces is seen, at present, as a matter of priority within theoretical high-energy physics. Some physicist identify this Theory of Everything today with aspecific type of superstring theory or its intended conceptual continuation, called M-Theory. The objective of this article is the discussion of the requirements a fundamental physical theory has to comply with. This question can only be clarified if one takes into account that the claim that a physical theory is all-encompassing takes forgranted some tacit prerequisites which concern the conceptual and epistemological foundations of science and, not least, the question for the realizability of its reductionistic unity. This revised version was published online in August 2006 with corrections to the Cover Date.     

A note on steady states and the weber-fechner law

The steady state of a simple reaction system has been shown to have some of the properties of a psychophysical discrimination system, including the possibility of deducing a generalized Weber-Fechner Law, both in integral form and in difference form. The Weber ratio so deduced is not constant, and its dependence on stimulus intensity is exhibited. The dependence of the difference limen on the internal threshold is discussed; it is found that in general there is a finite value of this threshold for which response is impossible. This critical threshold is lower for higher values of the reference stimulus intensity. Similarly, it is shown that the difference limen and the Weber ratio, for a fixed value of the threshold, become infinite (i.e., discrimination is impossible) for a value of the stimulus intensity which in general is finite.     

Explanatory warrant for scientific realism

Nancy Cartwright relies upon an inference pattern known as inference to the best causal explanation (IBCE) to support a limited form of entity realism, according to which we are warranted in believing in entities that purportively cause observable effects. IBCE, as usually understood, is valid, even though all other forms of inference to the best explanation (IBE) are usually understood to be invalid. We argue that IBCE and IBE are in the same boat with respect to their ability to support realist conclusions. Either rule can be interpreted as valid, this is a matter of semantic convention. However, doing so deprives the rule of the empirical content the realist needs, requiring the realist to find independent warrant for a strong (theoretical or causal) premise. We then examine the proposed means of obtaining this warrant, and find them as inadequate in the case of IBCE as they are in the case of IBE.     

The Internal and External Problems of String Theory: A Philosophical View

String theory is at the moment the only advanced approach to a unification of all interactions, including gravity. But, in spite of the more than 30 years of its existence, it does not make any empirically testable predictions, and it is completely unknown which physically interpretable principles could form the basis of string theory. At the moment, “string theory” is no theory at all, but rather a labyrinthic structure of mathematical procedures and intuitions. The only motivations for string theory consist in the mutual incompatibility of the standard model of quantum field theory and of general relativity as well as in the metaphysics of the unification program of physics, aimed at a final unified theory of all interactions, including gravity. The article gives a perspective on the problems leading to and resulting from this situation.

Commodious Axiomatization of Quantifiers in Multiple-Valued Logic

We provide tools for a concise axiomatization of a broad class of quantifiers in many-valued logic, so-called distribution quantifiers. Although sound and complete axiomatizations for such quantifiers exist, their size renders them virtually useless for practical purposes. We show that for quantifiers based on finite distributive lattices compact axiomatizations can be obtained schematically. This is achieved by providing a link between skolemized signed formulas and filters/ideals in Boolean set lattices. Then lattice theoretic tools such as Birkhoff's representation theorem for finite distributive lattices are used to derive tableau-style axiomatizations of distribution quantifiers.     

The selective attention of learning-disabled children: Three studies

Three studies were performed to assess the selective attention of learning-disabled (LD) children. In the first study, 10 LD and 16 non-LD children were given the Speeded Classification task. LD children sorted cards more slowly than non-LD children, and children in both groups had trouble ignoring irrelevant information. Non-LD children became more accurate across trials, while LD children did not. In the second study, one group of 13 LD children was taught to accompany their Speeded Classification sorting verbally in an attempt to improve their performance; the other group of LD children (n=12) received no such instruction. The experimental group, however, showed poorer performance across trials compared with the control group. In the third study, the children from Experiments 1 and 2 were given the Central-Incidental Learning task. Older children learned more central memory items than younger children and, LD children learned more incidentally than non-LD children.The authors would like to thank James Merola, Lisa Hart, Donna Woods, and Leonne Paquette for their assistance in this project, and the headmaster, director, teachers, and staff who were so helpful. Parts of this paper were presented at the 1982 meeting of the American Psychological Association.     

Current Concerns and Electrodermal Reactivity: Responses to Words and Thoughts

ABSTRACT Previous research has found that subjects rate words that are closely related to their current concerns as affectively more arousing than other words. This investigation inquires whether a similar relationship occurs when arousal is measured electrodermally, and whether nonspecific (spontaneous) electrodermal activity is associated with self-generated thoughts about current concerns. In the first experiment, subjects listened to audiotaped sequences of three-word clusters associated with previously measured own current concerns or with concerns of others. Mean skin conductance responses were significantly larger for clusters related to subjects' own concerns than for those related to others' concerns, although many subjects contributing to this effect showed some awareness of the hypothesis. In the second experiment, thoughts that accompanied nonspecific skin conductance responses received significantly higher self-ratings for concern-relatedness and arousal than thoughts that occurred during electrodermal inactivity. In Experiment 3, they were rated higher for current-concern content and anxiety and lower for mental imagery and dormant-concern content than thoughts during electrodermal inactivity.