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Depositional Patterns of Miocene Facies, Middle Texas Coastal Plain
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Attitudes, Ideological Associations and the LeftâRight Divide in Latin America
Do Latin American citizens share a common conception of the ideological leftâright distinction? And if so, is this conception linked to individualsâ ideological self-placement? Selecting questions from the 2006
LatinobarĂłmetro survey based on a core definition of the leftâright divide rooted in political theory and philosophy, this paper addresses these questions.
We apply joint correspondence analysis to explore whether citizens who relate to the same ideological identification also share similar and coherent convictions and beliefs that reflect the ideological content of the leftâright distinction. Our analysis indicates that theoretical conceptions about
the roots of, and responsibility for, inequality in society, together with the
translation of these beliefs into attitudes regarding the state versus market divide, distinguish those who self-identify with the left and those who selfidentify with the right
Slow, Continuous Beams of Large Gas Phase Molecules
Cold, continuous, high flux beams of benzonitrile, fluorobenzine, and anisole
have been created. Buffer-gas cooling with a cryogenic gas provides the cooling
and slow forward beam velocities. The beam of benzonitrile was measured to have
a forward velocity peaked at 67 m s, and a continuous flux of
molecules s. These beams provide a continuous source for high
resolution spectroscopy, and provide an attractive starting point for further
spatial manipulation of such molecules, including eventual trapping
Contrasting Views of Complexity and Their Implications For Network-Centric Infrastructures
There exists a widely recognized need to better understand
and manage complex âsystems of systems,â ranging from
biology, ecology, and medicine to network-centric technologies.
This is motivating the search for universal laws of highly evolved
systems and driving demand for new mathematics and methods
that are consistent, integrative, and predictive. However, the theoretical
frameworks available today are not merely fragmented
but sometimes contradictory and incompatible. We argue that
complexity arises in highly evolved biological and technological
systems primarily to provide mechanisms to create robustness.
However, this complexity itself can be a source of new fragility,
leading to ârobust yet fragileâ tradeoffs in system design. We
focus on the role of robustness and architecture in networked
infrastructures, and we highlight recent advances in the theory
of distributed control driven by network technologies. This view
of complexity in highly organized technological and biological systems
is fundamentally different from the dominant perspective in
the mainstream sciences, which downplays function, constraints,
and tradeoffs, and tends to minimize the role of organization and
design
Quantum Uncertainty Considerations for Gravitational Lens Interferometry
The measurement of the gravitational lens delay time between light paths has
relied, to date, on the source having sufficient variability to allow
photometric variations from each path to be compared. However, the delay times
of many gravitational lenses cannot be measured because the intrinsic source
amplitude variations are too small to be detectable. At the fundamental quantum
mechanical level, such photometric time stamps allow which-path knowledge,
removing the ability to obtain an interference pattern. However, if the two
paths can be made equal (zero time delay) then interference can occur. We
describe an interferometric approach to measuring gravitational lens delay
times using a quantum-eraser/restorer approach, whereby the time travel along
the two paths may be rendered measurably equal. Energy and time being
non-commuting observables, constraints on the photon energy in the energy-time
uncertainty principle, via adjustments of the width of the radio bandpass,
dictate the uncertainty of the time delay and therefore whether the path taken
along one or the other gravitational lens geodesic is knowable. If one starts
with interference, for example, which-path information returns when the
bandpass is broadened (constraints on the energy are relaxed) to the point
where the uncertainty principle allows a knowledge of the arrival time to
better than the gravitational lens delay time itself, at which point the
interference will disappear. We discuss the near-term feasibility of such
measurements in light of current narrow-band radio detectors and known short
time-delay gravitational lenses.Comment: 22 page
Design degrees of freedom and mechanisms for complexity
We develop a discrete spectrum of percolation forest fire models characterized by increasing design degrees of freedom (DDOFâs). The DDOFâs are tuned to optimize the yield of trees after a single spark. In the limit of a single DDOF, the model is tuned to the critical density. Additional DDOFâs allow for increasingly refined spatial patterns, associated with the cellular structures seen in highly optimized tolerance (HOT). The spectrum of models provides a clear illustration of the contrast between criticality and HOT, as well as a concrete quantitative example of how a sequence of robustness tradeoffs naturally arises when increasingly complex systems are developed through additional layers of design. Such tradeoffs are familiar in engineering and biology and are a central aspect of the complex systems that can be characterized as HOT
Mathematics and the Internet: A Source of Enormous Confusion and Great Potential
Graph theory models the Internet mathematically, and a number of plausible mathematically intersecting network models for the Internet have been developed and studied. Simultaneously, Internet researchers have developed methodology to use real data to validate, or invalidate, proposed Internet models. The authors look at these parallel developments, particularly as they apply to scale-free network models of the preferential attachment type
The magnitude distribution of earthquakes near Southern California faults
We investigate seismicity near faults in the Southern California Earthquake Center Community Fault Model. We search for anomalously large events that might be signs of a characteristic earthquake distribution. We find that seismicity near major fault zones in Southern California is well modeled by a Gutenberg-Richter distribution, with no evidence of characteristic earthquakes within the resolution limits of the modern instrumental catalog. However, the b value of the locally observed magnitude distribution is found to depend on distance to the nearest mapped fault segment, which suggests that earthquakes nucleating near major faults are likely to have larger magnitudes relative to earthquakes nucleating far from major faults
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