Fehler im Haus der Vernunft

The first part of the essay tries to show that Davidson's explanation of irrationality in terms of a fragmentation of the mind is not compatible with interpretationist premises of his own theory. Instead of adopting the conception of two semi-autonomous departments of the mind, I argue for an explanation of strong forms of irrationality based on two kinds of contentful mental states: functionally individuated representational states and states whose content depends on a rationalizing interpretation. Akrasia - as a form of irrationality caused by mental states that are not propositionally transparent - seems to fit neatly into that pictur

Vibrational phenomena in glasses at low temperatures captured by field theory of disordered harmonic oscillators

We investigate the vibrational properties of topologically disordered materials by analytically studying particles that harmonically oscillate around random positions. Exploiting field theory in the thermodynamic limit at $T=0$, we build up a self-consistent model by analysing the Hessian utilizing Euclidean Random Matrix theory. In accordance with earlier findings [1], we take non-planar diagrams into account to correctly address multiple local scattering events. By doing so, we end up with a first principles theory that can predict the main anomalies of athermal disordered materials, including the boson peak, sound softening, and Rayleigh damping of sound. In the vibrational density of states, the sound modes lead to Debye's law for small frequencies. Additionally, quasi-localised modes (QLMs), cause an excess in the density of states starting as $\omega^4$ in the low frequency limit.Comment: 6 pages, 5 figures; 7 pages of supplemental informatio

Near-equilibrium measurement of quantum size effects using Kelvin probe force microscopy

In nano-structures such as thin films electron confinement results in the quantization of energy levels in the direction perpendicular to the film. The discretization of the energy levels leads to the oscillatory dependence of many properties on the film thickness due to quantum size effects. Pb on Si(111) is a specially interesting system because a particular relationship between the Pb atomic layer thickness and its Fermi wavelength leads to a periodicity of the oscillation of two atomic layers. Here, we demonstrate how the combination of scanning force microscopy (SFM) and Kelvin probe force microscopy (KPFM) provides a reliable method to monitor the quantum oscillations in the work function of Pb ultra-thin film nano-structures on Si(111). Unlike other techniques, with SFM/KPFM we directly address single Pb islands, determine their height while suppressing the influence of electrostatic forces, and, in addition, simultaneously evaluate their local work function by measurements close to equilibrium, without current-dependent and non-equilibrium effects. Our results evidence even-odd oscillations in the work function as a function of the film thickness that decay linearly with the film thickness, proving that this method provides direct and precise information on the quantum states.Comment: This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Nanoscale, copyright Royal Society of Chemistry after peer review. To access the final edited and published work see doi belo

NMR Studies on the Temperature-Dependent Dynamics of Confined Water

We use $^2$H NMR to study the rotational motion of supercooled water in silica pores of various diameters, specifically, in the MCM-41 materials C10, C12, and C14. Combination of spin-lattice relaxation, line-shape, and stimulated-echo analyses allows us to determine correlation times in very broad time and temperature ranges. For the studied pore diameters, 2.1-2.9 nm, we find two crossovers in the temperature-dependent correlation times of liquid water upon cooling. At 220-230 K, a first kink in the temperature dependence is accompanied by a solidification of a fraction of the confined water, implying that the observed crossover is due to a change from bulk-like to interface-dominated water dynamics, rather than to a liquid-liquid phase transition. Moreover, the results provide evidence that $\alpha$ process-like dynamics is probed above the crossover temperature, whereas $\beta$ process-like dynamics is observed below. At 180-190 K, we find a second change of the temperature dependence, which resembles that reported for the $\beta$ process of supercooled liquids during the glass transition, suggesting a value of $T_g\!\approx\!185$ K for interface-affected liquid water. In the high-temperature range, $T\!>\!225$ K, the temperature dependence of water reorientation is weaker in the smaller C10 pores than in the larger C12 and C14 pores, where it is more bulk-like, indicating a significant effect of the silica confinement on the $\alpha$ process of water in the former 2.1 nm confinement. By contrast, the temperature dependence of water reorientation is largely independent of the confinement size and described by an Arrhenius law with an activation energy of $E_a\!\approx\!0.5\$eV in the low-temperature range, $T\!<\!180$K, revealing that the confinement size plays a minor role for the $\beta$ process of water.Comment: 12 pages, 9 figure

Communicating Unknown Words in Machine Translation

A new approach to handle unknown words in machine translation is presented. The basic idea is to find definitions for the unknown words on the source language side and translate those definitions instead. Only monolingual resources are required, which generally offer a broader coverage than bilingual resources and are available for a large number of languages. In order to use this in a machine translation system definitions are extracted automatically from online dictionaries and encyclopedias. The translated definition is then inserted and clearly marked in the original hypothesis. This is shown to lead to significant improvements in (subjective) translation quality

Language Model Adaptation for Statistical Machine Translation with Structured Query Models

We explore unsupervised language model adaptation techniques for Statistical Machine Translation. The hypotheses from the machine translation output are converted into queries at different levels of representation power and used to extract similar sentences from very large monolingual text collection. Specific language models are then build from the retrieved data and interpolated with a general background model. Experiments show significant improvements when translating with these adapted language models