We apply an online optimization process based on machine learning to the production of Bose-Einstein condensates. BEC is typically created with an exponential evaporation ramp that is optimal for ergodic dynamics with two-body s-wave interactions and no other loss rates, but likely sub-optimal for real experiments. Through repeated machine-controlled scientific experimentation and observations our ’learner’ discovers an optimal evaporation ramp for BEC production. In contrast to previous work, our learner uses a Gaussian process to develop a statistical model of (...) the relationship between the parameters it controls and the quality of the BEC produced. We demonstrate that the Gaussian process machine learner is able to discover a ramp that produces high quality BECs in 10 times fewer iterations than a previously used online optimization technique. Furthermore, we show the internal model developed can be used to determine which parameters are essential in BEC creation and which are unimportant, providing insight into the optimization process of the system. (shrink)

In De Partibus Animalium I Aristotle sets out his philosophy of biology, discussing cause, necessity, soul, genus, and species, definition by logical division, and general methodology. In De Generatione Animalium I he applies his hylomorphic philosophy to the problem of animal reproduction. The translation is close, and includes passages from De Generatione Animalium II which complete Aristotle's theory of reproduction. The notes interpret Aristotle's arguments and discuss his views on major issues such as natural teleology. The original edition was published (...) in 1972. (shrink)

We introduce reactive Kripke models for intuitionistic logic and show that the reactive semantics is stronger than the ordinary semantics. We develop Beth tableaux for the reactive semantics.

This collection of original essays covers a wide range of issues in current naturalised philosophy of mind. Particular attention is paid to the ways in which concepts drawn from evolutionary biology might enhance our understanding of the place of mind in the natural world. Issues covered include the advantages of construing the mind as an adaptation, the naturalisation of intentional and phenomenal content, the evolution of means-end reasoning, rationality and higher-order intentionality, methodological issues in cognitive ethology and evolutionary psychology.

The structure of the thermal equilibrium state of a weakly interacting Bose gas is of current interest. We calculate the density matrix of that state in two ways. The most effective method, in terms of yielding a simple, explicit answer, is to construct a generating function within the traditional framework of quantum statistical mechanics. The alternative method, arguably more interesting, is to construct the thermal state as a vector state in an artificial system with twice as many degrees of (...) freedom. It is well known that this construction has an actual physical realization in the quantum thermodynamics of black holes, where the added degrees of freedom correspond to the second sheet of the Kruskal manifold and the thermal vector state is a state of the Unruh or the Hartle–Hawking type. What is unusual about the present work is that the Bogolubov transformation used to construct the thermal state combines in a rather symmetrical way with Bogolubov's original transformation of the same form, used to implement the interaction of the nonideal gas in linear approximation. In addition to providing a density matrix, the method makes it possible to calculate efficiently certain expectation values directly in terms of the thermal vector state of the doubled system. (shrink)

John Foster’s book, The Nature of Perception, is written to defend his Idealist, or Berkeleyan, theory of perception. One view that he is concerned to reject is what he usefully calls the ‘Cognitivist’ theory of perception. I am named as one of its defenders. His critique of the theory serves me as a good starting point and as a stimulus for a new defense of the theory.

This book constitutes the refereed proceedings of the International Conference on Spatial Information Theory, COSIT 2005, held in Elliottville, NY, USA in September 2005. The 30 revised full papers presented were carefully reviewed and selected from 82 submissions. The papers are organized in topical sections on vagueness, uncertainty, and gradation; paths and routes; ontologies and semantics; ontologies and spatial relations; spatial reasoning: cognitive maps and spatial reasoning; time, change, and dynamics; landmarks and navigation; geographic information, and spatial behaviour.