2,895 research outputs found

    The Right to Learn: Intellectual Honesty and the First Amendment

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    Science education is one of the most hotly contested issues in public debate. Even after decades of jurisprudence and scholarly analysis, politicians still ignite public passions by suggesting that creationism or intelligent design theory be taught alongside of evolution in public school science classrooms. Despite political rhetoric, the Establishment Clause has been steadfastly used to prevent religion masquerading as science from entering the science classroom. However, public officials have launched attacks recently on other scientific theories, such as climate change, that are not religiously motivated. Students are left in these instances without resort to the Establishment Clause and are potentially forced to learn propaganda and psuedo-science in science classrooms. This Article confronts the vexing problem that students are protected from psuedoscience that is religiously based and not psuedo-science that is politically motivated, even though they are both equally damaging to the students\u27 education. There is no intellectual or constitutional basis for banning some kinds of pseudo-science and allowing others within a compulsory public science class. This Article is the first to argue that students in public school science classrooms are entitled to an accurate and honest rendering of the scientific facts free from propaganda, proselytizing and politics under the Free Speech Clause of the First Amendment. Simply because a scientific theory is attacked for political motivations does not render it constitutionally permissible. So long as students are required by compulsory education laws to attend science class, the state is constitutionally required to protect the students\u27 right to learn. This right to learn is rooted in a long and distinguished line of cases. Not only does it have a judicial pedigree, but the right to learn rooted in the Free Speech Clause shifts the constitutional analysis from the difficult task of determining motivations to the pursuit of scientific accuracy

    On Toroidal Horizons in Binary Black Hole Inspirals

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    We examine the structure of the event horizon for numerical simulations of two black holes that begin in a quasicircular orbit, inspiral, and finally merge. We find that the spatial cross section of the merged event horizon has spherical topology (to the limit of our resolution), despite the expectation that generic binary black hole mergers in the absence of symmetries should result in an event horizon that briefly has a toroidal cross section. Using insight gained from our numerical simulations, we investigate how the choice of time slicing affects both the spatial cross section of the event horizon and the locus of points at which generators of the event horizon cross. To ensure the robustness of our conclusions, our results are checked at multiple numerical resolutions. 3D visualization data for these resolutions are available for public access online. We find that the structure of the horizon generators in our simulations is consistent with expectations, and the lack of toroidal horizons in our simulations is due to our choice of time slicing.Comment: Submitted to Phys. Rev.

    Demonstration of Active Combustion Control

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    The primary objective of this effort was to demonstrate active control of combustion instabilities in a direct-injection gas turbine combustor that accurately simulates engine operating conditions and reproduces an engine-type instability. This report documents the second phase of a two-phase effort. The first phase involved the analysis of an instability observed in a developmental aeroengine and the design of a single-nozzle test rig to replicate that phenomenon. This was successfully completed in 2001 and is documented in the Phase I report. This second phase was directed toward demonstration of active control strategies to mitigate this instability and thereby demonstrate the viability of active control for aircraft engine combustors. This involved development of high-speed actuator technology, testing and analysis of how the actuation system was integrated with the combustion system, control algorithm development, and demonstration testing in the single-nozzle test rig. A 30 percent reduction in the amplitude of the high-frequency (570 Hz) instability was achieved using actuation systems and control algorithms developed within this effort. Even larger reductions were shown with a low-frequency (270 Hz) instability. This represents a unique achievement in the development and practical demonstration of active combustion control systems for gas turbine applications

    Prevention for a Healthier California: Investments in Disease Prevention Yield Significant Savings, Stronger Communities

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    Estimates how much the state and the nation could save in healthcare costs by investing in disease prevention through community programs that increase physical activity, improve nutrition, and reduce tobacco use. Provides examples of prevention efforts

    Mixer assembly for a gas turbine engine having a pilot mixer with a corner flame stabilizing recirculation zone

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    A mixer assembly for a gas turbine engine is provided, including a main mixer, and a pilot mixer having an annular housing in which a corner is formed between an aft portion of the housing and a bulkhead wall in which a corner recirculation zone is located to stabilize and anchor the flame of the pilot mixer. The pilot mixer can further include features to cool the annular housing, including in the area of the corner recirculation zone

    Teaching White Collar Crime: A Fresh Perspective

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    Combustor Assembly for a Turbine Engine

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    A combustor assembly includes a first wall, a second wall, a bulkhead and a plurality of fuel injectors. The bulkhead forms a combustion chamber with the first and the second walls. The fuel injectors are configured with the first wall in a unique and/or a fluctuating pattern
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