287 research outputs found
Origin of Magnetic Fields in the Universe Due to Nonminimal Gravitational-Electromagnetic Coupling
Basically the only existing theories for the creation of a magnetic field B
in the Universe are the creation of a seed field of order 10^{-20} G in spiral
galaxy which is subsequently supposedly amplified up to the observed 10^{-6} -
10^{-5} G by a dynamo process or a seed intergalactic field of magnitude
10^{-12} - 10^{-10} G which is amplified by collapse and differential rotation.
No satisfactory dynamo theory, however, exists today. We show that a 10^{-6} -
10^{-5} G magnetic field in spiral galaxies is directly obtained from a
nonminimal gravitational-electromagnetic coupling, without the need of
significant dynamo amplification.Comment: 5 pages, Latex (Revtex), no figures, To appear in PR
New Evidence for a Change with Time of the Total Energy Brought into the Earth by Cosmic Rays
Geologically recent areas as one key target for identifying active volcanism on Venus
The recently selected NASA VERITAS and DAVINCI missions, the ESA EnVision, the Roscosmos Venera-D will open a new era in the exploration of Venus. One of the key targets of the future orbiting and in situ investigations of Venus is the identification of volcanically active areas on the planet. The study of the areas characterized by recent or ongoing volcano-tectonic activity can inform us on how volcanism and tectonism are currently evolving on Venus. Following this key target, Brossier et al. (2022, https://doi.org/10.1029/2022GL099765) extend the successful approach and methodology used by previous works to Ganis Chasma in Atla Regio. Here we comment on the main results published in Brossier et al. (2022, https://doi.org/10.1029/2022GL099765) and discuss the important implications of their work for the future orbiting and in situ investigation of Venus. Their results add further lines of evidence indicating possibly recent volcanism on Venus
An Experimental Investigation of Colonel Blotto Games
"This article examines behavior in the two-player, constant-sum Colonel Blotto game with asymmetric resources in which players maximize the expected number of battlefields won. The experimental results support all major theoretical predictions. In the auction treatment, where winning a battlefield is deterministic, disadvantaged players use a 'guerilla warfare' strategy which stochastically allocates zero resources to a subset of battlefields. Advantaged players employ a 'stochastic complete coverage' strategy, allocating random, but positive, resource levels across the battlefields. In the lottery treatment, where winning a battlefield is probabilistic, both players divide their resources equally across all battlefields." (author's abstract)"Dieser Artikel untersucht das Verhalten von Individuen in einem 'constant-sum Colonel Blotto'-Spiel zwischen zwei Spielern, bei dem die Spieler mit unterschiedlichen Ressourcen ausgestattet sind und die erwartete Anzahl gewonnener Schlachtfelder maximieren. Die experimentellen Ergebnisse bestĂ€tigen alle wichtigen theoretischen Vorhersagen. Im Durchgang, in dem wie in einer Auktion der Sieg in einem Schlachtfeld deterministisch ist, wenden die Spieler, die sich im Nachteil befinden, eine 'Guerillataktik' an, und verteilen ihre Ressourcen stochastisch auf eine Teilmenge der Schlachtfelder. Spieler mit einem Vorteil verwenden eine Strategie der 'stochastischen vollstĂ€ndigen Abdeckung', indem sie zufĂ€llig eine positive Ressourcenmenge auf allen Schlachtfeldern positionieren. Im Durchgang, in dem sich der Gewinn eines Schlachtfeldes probabilistisch wie in einer Lotterie bestimmt, teilen beide Spieler ihre Ressourcen gleichmĂ€Ăig auf alle Schlachtfelder auf." (Autorenreferat
Underground railroads: citizen entitlements and unauthorized mobility in the antebellum period and today
In recent years, some scholars and prominent political figures have advocated the deepening of North American integration on roughly the European Union model, including the creation of new political institutions and the free movement of workers across borders. The construction of such a North American Union, if it included even a very thin trans-state citizenship regime, could represent the most significant expansion of individual entitlements in the region since citizenship was extended to former slaves in the United States. With such a possibility as its starting point, this article explores some striking parallels between the mass, legally prohibited movement across boundaries by fugitive slaves in the pre-Civil War period, and that by current unauthorized migrants to the United States. Both were, or are, met on their journeys by historically parallel groups of would-be helpers and hinderers. Their unauthorized movements in both periods serve as important signals of incomplete entitlements or institutional protections. Most crucially, moral arguments for extending fuller entitlements to both groups are shown here to be less distinct than may be prima facie evident, reinforcing the case for expanding and deepening the regional membership regime
Internally Electrodynamic Particle Model: Its Experimental Basis and Its Predictions
The internally electrodynamic (IED) particle model was derived based on
overall experimental observations, with the IED process itself being built
directly on three experimental facts, a) electric charges present with all
material particles, b) an accelerated charge generates electromagnetic waves
according to Maxwell's equations and Planck energy equation and c) source
motion produces Doppler effect. A set of well-known basic particle equations
and properties become predictable based on first principles solutions for the
IED process; several key solutions achieved are outlined, including the de
Broglie phase wave, de Broglie relations, Schr\"odinger equation, mass,
Einstein mass-energy relation, Newton's law of gravity, single particle self
interference, and electromagnetic radiation and absorption; these equations and
properties have long been broadly experimentally validated or demonstrated. A
specific solution also predicts the Doebner-Goldin equation which emerges to
represent a form of long-sought quantum wave equation including gravity. A
critical review of the key experiments is given which suggests that the IED
process underlies the basic particle equations and properties not just
sufficiently but also necessarily.Comment: Presentation at the 27th Int Colloq on Group Theo Meth in Phys, 200
Spin half fermions with mass dimension one: theory, phenomenology, and dark matter
We provide the first details on the unexpected theoretical discovery of a
spin-one-half matter field with mass dimension one. It is based upon a complete
set of dual-helicity eigenspinors of the charge conjugation operator. Due to
its unusual properties with respect to charge conjugation and parity, it
belongs to a non-standard Wigner class. Consequently, the theory exhibits
non-locality with (CPT)^2 = - I. We briefly discuss its relevance to the
cosmological `horizon problem'. Because the introduced fermionic field is
endowed with mass dimension one, it can carry a quartic self-interaction. Its
dominant interaction with known forms of matter is via Higgs, and with gravity.
This aspect leads us to contemplate the new fermion as a prime dark matter
candidate. Taking this suggestion seriously we study a supernova-like explosion
of a galactic-mass dark matter cloud to set limits on the mass of the new
particle and present a calculation on relic abundance to constrain the relevant
cross-section. The analysis favours light mass (roughly 20 MeV) and relevant
cross-section of about 2 pb. Similarities and differences with the WIMP and
mirror matter proposals for dark matter are enumerated. In a critique of the
theory we bare a hint on non-commutative aspects of spacetime, and
energy-momentum space.Comment: 78 pages [Changes: referee-suggested improvements, additional
important references, and better readability
Ultrahigh Energy Cosmic Rays: The state of the art before the Auger Observatory
In this review we discuss the important progress made in recent years towards
understanding the experimental data on cosmic rays with energies \agt 10^{19}
eV. We begin with a brief survey of the available data, including a description
of the energy spectrum, mass composition, and arrival directions. At this point
we also give a short overview of experimental techniques. After that, we
introduce the fundamentals of acceleration and propagation in order to discuss
the conjectured nearby cosmic ray sources. We then turn to theoretical notions
of physics beyond the Standard Model where we consider both exotic primaries
and exotic physical laws. Particular attention is given to the role that
TeV-scale gravity could play in addressing the origin of the highest energy
cosmic rays. In the final part of the review we discuss the potential of future
cosmic ray experiments for the discovery of tiny black holes that should be
produced in the Earth's atmosphere if TeV-scale gravity is realized in Nature.Comment: Final version. To be published in Int. J. Mod. Phys.
Mount Etna as a terrestrial laboratory to investigate recent volcanic activity on Venus by future missions:A comparison with Idunn Mons, Venus
The recently selected missions to Venus have opened a new era for the exploration of this planet. These missions will provide information about the chemistry of the atmosphere, the geomorphology, local-to-regional surface composition, and the rheology of the interior. One key scientific question to be addressed by these future missions is whether Venus remains volcanically active, and if so, how its volcanism is currently evolving. Hence, it is fundamental to analyze appropriate terrestrial analog sites for the study of possibly active volcanism on Venus. To this regard, we propose Mount Etna - one of the most active and monitored volcanoes on Earth - as a suitable terrestrial laboratory for remote and in-situ investigations to be performed by future missions to Venus. Being characterized by both effusive and explosive volcanic products, Mount Etna offers the opportunity to analyze multiple eruptive styles, both monitoring active volcanism and identifying the possible occurrence of pyroclastic activity on Venus. We directly compare Mount Etna with Idunn Mons, one of the most promising potentially active volcanoes of Venus. Despite the two structures show a different topography, they also show some interesting points of comparison, and in particular: a) comparable morpho-structural setting, since both volcanoes interact with a rift zone, and b) morphologically similar volcanic fields around both Mount Etna and Idunn Mons. Given its ease of access, we also propose Mount Etna as an analog site for laboratory spectroscopic studies to identify the signatures of unaltered volcanic deposits on Venus
Soft systems methodology: a context within a 50-year retrospective of OR/MS
Soft systems methodology (SSM) has been used in the practice of operations research and management science OR/MS) since the early 1970s. In the 1990s, it emerged as a viable academic discipline. Unfortunately, its proponents consider SSM and traditional systems thinking to be mutually exclusive. Despite the differences claimed by SSM proponents between the two, they have been complementary. An extensive sampling of the OR/MS literature over its entire lifetime demonstrates the richness with which the non-SSM literature has been addressing the very same issues as does SSM
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