Kitcher, Correspondence, and Success

Concerned that deflationary theories of truth threaten his scientific realism, Philip Kitcher has constructed an argument that scientific success establishes not only the truth of crucial scientific beliefs but also their *correspondence* truth. This paper interprets and evaluates Kitcher’s argument, ultimately finding it to be both unsound and unmotivated

Can There Be a Knowledge-First Ethics of Belief?

This article critically examines numerous attempts to build a knowledge-first ethics of belief. These theories specify a number of potential "knowledge norms for belief"

Some Epistemic Roles for Curiosity

I start with a critical discussion of some attempts to ground epistemic normativity in curiosity. Then I develop three positive proposals. The first of these proposals is more or less purely philosophical; the second two reside at the interdisciplinary borderline between philosophy and psychology. The proposals are independent and rooted in different literatures. Readers uninterested in the first proposal (and the critical discussion preceding it) may nonetheless be interested in the second two proposals, and vice versa. The proposals are as follows. First I argue that, among several ways in which the notion of curiosity might be used to delineate significant truths from trivial ones, a particular way is the most promising. Second, I argue that curiosity has some underappreciated epistemic roles involving memory. Third, I argue that curiosity has some underappreciated epistemic roles involving coherence

Airfoil shape for flight at subsonic speeds

An airfoil is examined that has an upper surface shaped to control flow accelerations and pressure distribution over the upper surface and to prevent separation of the boundary layer due to shock wave formulation at high subsonic speeds well above the critical Mach number. A highly cambered trailing edge section improves overall airfoil lifting efficiency. Diagrams illustrating supersonic flow and shock waves over the airfoil are shown

Ground-based gravitational-wave detection: now and future

In the past three years, the first generation of large gravitational-wave interferometers has begun operation near their design sensitivities, taking up the mantle from the bar detectors that pioneered the search for the first direct detection of gravitational waves. Even as the current ground-based interferometers were reaching their design sensitivities, plans were being laid for the future. Advances in technology and lessons learned from the first generation devices have pointed the way to an order of magnitude improvement in sensitivity, as well as expanded frequency ranges and the capability to tailor the sensitivity band to address particular astrophysical sources. Advanced cryogenic acoustic detectors, the successors to the current bar detectors, are being researched and may play a role in the future, particularly at the higher frequencies. One of the most important trends is the growing international cooperation aimed at building a truly global network. In this paper, I survey the state of the various detectors as of mid-2007, and outline the prospects for the future

Featured Piece

This year’s feature piece was written by Professor Kathryn Whitcomb who is new to Gettysburg College’s Department of Classics. In addition to Classics courses, she has taught courses that have been cross-listed with the History Department and thus adds to the diversity that make the historical field so great and broadens the horizons of historical scholarship to her students

The Laser Interferometer Gravitational Wave Observatory (LIGO) project

The LIGO (Laser Interferometer Gravitational-Wave Observatory) project is designed to open a new field of science by detecting and studying the gravitational waves from astrophysical sources, including neutron stars, black holes, and possibly, supernovae and the big bang. LIGO will consist of two scientific facilities, each incorporating an L-shaped vacuum system with 4-kilometers arms to house sensitive interferometers. A detector system consists of three interferometers, two at one site and one at the other. Each interferometer measures the motion of a set of test masses which are suspended from seismically isolated supports and free to move in response to gravitational waves. Correlations among the three interferometers will be used to eliminate local noise. LIGO is designed to support a sequence of detector systems of increasing sensitivity over the next twenty years or longer. In its initial configuration, it will have just one detector system. However, its design permits expansion to support three simultaneous detector systems. The project received funding in 1992 to begin design and construction. Sites for the two facilities (Hanford, Washington and Livingston, Louisiana) have been selected. Under the present schedule, the facilities will be completed by 1997 and initial observations will begin in 1998. Ultimately, the LIGO will be operated in coordination with interferometers in Europe and elsewhere, to form a worldwide gravitational wave observatory network

Introductory Remarks

Advanced transonic configurations, such as the supercritical wing, are inherently more sensitive to Reynolds number than earlier configurations because the pressure recovery gradients imposed on the boundary layer are generally steeper. The results of two-dimensional supercritical airfoil investigations and theoretical calculations show this effect. A technique for approximately simulating full-scale Reynolds number characteristics at present wind-tunnel Reynolds numbers for near-cruise conditions is described. The transition strip, which in the past has been located near the leading edge of the wing, is rearward so that the relative displacement thickness of the boundary layer at the trailing edge of the wing is the same as might be expected on a full-scale configuration with the transition near the leading edge. Two-dimensional wind-tunnel results indicate that the technique provides a very good simulation of airfoil characteristics at full-scale Reynolds number. The need for sorting the effects of Reynolds number and aeroelasticity, which can be done in the NTF, is also addressed