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Accretion Disks and Dynamos: Toward a Unified Mean Field Theory  [PDF]
Eric G. Blackman
Physics , 2012, DOI: 10.1088/0031-8949/86/05/058202
Abstract: Conversion of gravitational energy into radiation in accretion discs and the origin of large scale magnetic fields in astrophysical rotators have often been distinct topics of research. In semi-analytic work on both problems it has been useful to presume large scale symmetries, necessarily resulting in mean field theories. MHD turbulence makes the underlying systems locally asymmetric and nonlinear. Synergy between theory and simulations should aim for the development of practical mean field models that capture essential physics and can be used for observational modeling. Mean field dynamo (MFD) theory and alpha-viscosity accretion theory exemplify such ongoing pursuits. 21st century MFD theory has more nonlinear predictive power compared to 20th century MFD theory, whereas accretion theory is still in a 20th century state. In fact, insights from MFD theory are applicable to accretion theory and the two are artificially separated pieces of what should be a single theory. I discuss pieces of progress that provide clues toward a unified theory. A key concept is that large scale magnetic fields can be sustained via local or global magnetic helicity fluxes or via relaxation of small scale magnetic fluctuations, without the kinetic helicity driver of 20th century textbooks. These concepts may help explain the formation of large scale fields that supply non-local angular momentum transport via coronae and jets in a unified theory of accretion and dynamos. In diagnosing the role of helicities and helicity fluxes in disk simulations, each disk hemisphere should be studied separately to avoid being misled by cancelation that occurs as a result of reflection asymmetry. The fraction of helical field energy in disks is expected to be small compared to the total field in each hemisphere as a result of shear, but can still be essential for large scale dynamo action.
Escalation, timing and severity of insurgent and terrorist events: Toward a unified theory of future threats  [PDF]
Neil F. Johnson
Quantitative Finance , 2011,
Abstract: I present a unified discussion of several recently published results concerning the escalation, timing and severity of violent events in human conflicts and global terrorism, and set them in the wider context of real-world and cyber-based collective violence and illicit activity. I point out how the borders distinguishing between such activities are becoming increasingly blurred in practice -- from insurgency, terrorism, criminal gangs and cyberwars, through to the 2011 Arab Spring uprisings and London riots. I review the robust empirical patterns that have been found, and summarize a minimal mechanistic model which can explain these patterns. I also explain why this mechanistic approach, which is inspired by non-equilibrium statistical physics, fits naturally within the framework of recent ideas within the social science literature concerning analytical sociology. In passing, I flag the fundamental flaws in each of the recent critiques which have surfaced concerning the robustness of these results and the realism of the underlying model mechanisms.
Coexistence of Insect Species Competing for a Pulsed Resource: Toward a Unified Theory of Biodiversity in Fluctuating Environments  [PDF]
Samuel Venner,Pierre-Fran?ois Pélisson,Marie-Claude Bel-Venner,Fran?ois Débias,Etienne Rajon,Frédéric Menu
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0018039
Abstract: One major challenge in understanding how biodiversity is organized is finding out whether communities of competing species are shaped exclusively by species-level differences in ecological traits (niche theory), exclusively by random processes (neutral theory of biodiversity), or by both processes simultaneously. Communities of species competing for a pulsed resource are a suitable system for testing these theories: due to marked fluctuations in resource availability, the theories yield very different predictions about the timing of resource use and the synchronization of the population dynamics between the competing species. Accordingly, we explored mechanisms that might promote the local coexistence of phytophagous insects (four sister species of the genus Curculio) competing for oak acorns, a pulsed resource.
Unified theory in the worldline approach  [PDF]
James P. Edwards
Physics , 2014, DOI: 10.1016/j.physletb.2015.09.038
Abstract: We explore unified field theories based on the gauge groups $SU(5)$ and $SO(10)$ using the worldline approach for chiral fermions with a Wilson loop coupling to a background gauge field. Representing path ordering and chiral projection operators with functional integrals has previously reproduced the sum over the chiralities and representations of standard model particles in a compact way. This paper shows that for $SU(5)$ the $\bar{\mathbf{5}}$ and $\mathbf{10}$ representations -- into which the Georgi-Glashow model places the left-handed fermionic content of the standard model -- appear naturally and with the familiar chirality. We carry out the same analysis for flipped $SU(5)$ and uncover a link to $SO(10)$ unified theory. We pursue this by exploring the $SO(10)$ theory in the same framework, the less established unified theory based on $SU(6)$ and briefly consider the Pati-Salam model using $SU(4) \!\times \!SU(2)\! \times\! SU(2)$.
On unified theory for continuities
Mahide Kü ük,Yal in Kü ük
International Journal of Mathematics and Mathematical Sciences , 2002, DOI: 10.1155/s0161171202005124
Abstract: The purpose of this study is to give a unified theory for some weak and strong continuous functions using operations.
Lagrangian-Hamiltonian unified formalism for field theory  [PDF]
A. Echeverría-Enríquez,C. López,J. Marín-Solano,M. C. Mu?oz-Lecanda,N. Román-Roy
Physics , 2002, DOI: 10.1063/1.1628384
Abstract: The Rusk-Skinner formalism was developed in order to give a geometrical unified formalism for describing mechanical systems. It incorporates all the characteristics of Lagrangian and Hamiltonian descriptions of these systems (including dynamical equations and solutions, constraints, Legendre map, evolution operators, equivalence, etc.). In this work we extend this unified framework to first-order classical field theories, and show how this description comprises the main features of the Lagrangian and Hamiltonian formalisms, both for the regular and singular cases. This formulation is a first step toward further applications in optimal control theory for PDE's.
Human Carcinogenesis: Toward a Unified Theory
Briana Marshall, Doug Dix
Open Access Library Journal (OALib Journal) , 2017, DOI: 10.4236/oalib.1103707
If either chance or environmental exposure was the dominant carcinogen, cancer risk would increase continuously with age, but it doesn’t. For all cancers studied, risk exhibits three phases: 1) Low risk at young ages, followed by 2) an increase in risk to a maximum at some later age, followed by 3) a plateau or decline in risk at advanced ages. Only a genetically-determined discontinuous process can explain this pattern. We analyzed differences in risk between tissues of tumor origin and between geographic locations, genders, races, and ethnicities for clues. Our analyses suggest that normal tissue differentiation is safe, but inadequate. At some critical age, regeneration or dedifferentiation is required and this is an invitation to carcinogenesis. Upon reaching this critical age, risk varies with the size of a target, which may correspond to the number of regenerating or dedifferentiating stem cells. Cancer incidence rates were analyzed for melanoma and cancers of the mouth, esophagus, stomach, small intestine, colon, rectum, liver, pancreas, larynx, bronchus, breast, and kidney in populations distributed worldwide and within the United States in two time eras. Over all cancers, in all populations, and both eras, the difference in age-specific rates between ages 50 and 40, d50-40, correlated strongly with age-standardized rates. Differences in d50-40 correlated strongly with differences in age-standardized rates between genders, races, and ethnicities. We suggest that, for the cancers studied, the critical age occurs between 40 and 50. If environmental exposure or segregating genes was the dominant carcinogen, the rank order of cancer risk between tissues of tumor origin would vary from one geographic location to another, because environment and segregating genes vary between geographic locations. Such variation was observed between rank order in Japan and rank order in other countries, but not between rank orders in the other countries. We suspect, therefore, that environment or segregating genes play an important role in determining the difference in rank order of risk for the tissues of tumor origin between Japan and other countries. If chance or environmental exposure was the dominant carcinogen, cancer risk would correlate strongly between pairs of cancers across populations, but it doesn’t. Coefficients of risk between pairs of cancers are, typically, moderate at best. Only mouth, larynx, bronchus, and kidney show strong coefficients. By our measures, cancer risk from aging exceeds cancer risk from other-than-aging causes in all populations in both eras. We suspect that the aging risk is determined by genes that are common to all members of our species, and we suggest that inhibiting tissue injury and unnecessary growth will reduce cancer risk.
Strings and Unified Field Theory  [PDF]
Mark D. Roberts
Physics , 2006,
Abstract: It is argued that string theory predicts unified field theory rather than general relativity coupled to matter fields. In unified field theory all the objects are geometrical, for strings the Kalb-Ramond matter field is identical to the asymmetric part of the metric except that the fields contribute to different sides of the field equations. The dilaton is related to the object of non-metricity.
Toward a Unified AGN Structure  [PDF]
Demosthenes Kazanas,Keigo Fukumura,Ehud Behar,Ioannis Contopoulos,Chris Shrader
Physics , 2012,
Abstract: We present a unified model for the structure and appearance of accretion powered sources across their entire luminosity range from galactic X-ray binaries to luminous quasars, with emphasis on AGN and their phenomenology. Central to this model is the notion of MHD winds launched from the accretion disks that power these objects. These winds provide the matter that manifests as blueshifted absorption features in the UV and X-ray spectra of a large fraction of these sources; furthermore, their density distribution in the poloidal plane determines the "appearance" (i.e. the column and velocity structure of these absorption features) as a function of the observer inclination angle. This work focuses on just the broadest characteristics of these objects; nonetheless, it provides scaling laws that allow one to reproduce within this model the properties of objects spanning a very wide luminosity range and viewed at different inclination angles, and trace them to a common underlying dynamical structure. Its general conclusion is that the AGN phenomenology can be accounted for in terms of three parameters: The wind mass flux in units of the Eddington value, $\dot m$, the observer's inclination angle $\theta$ and the logarithmic slope between the O/UV and X-ray fluxes $\alpha_{OX}$. However, because of a significant correlation between $\alpha_{OX}$ and UV luminosity, we conclude that the AGN structure depends on only two parameters. Interestingly, the correlations implied by this model appear to extend to and consistent with the characteristics of galactic X-ray sources, suggesting the presence of a truly unified underlying structure for accretion powered sources.

Zhan Xiaolong,

地理学报 , 1989,
Abstract: : The purpose of this paper is to study the unified harmony of natural boundaries. First, it describes the main characters of the natural houndaries and what the unified harmony of the natural boundariesis. Second, it gives qualitative and quantitative analyses to the relations among the natural boundaries. On the basis of analysing, the coincilent degerees of Lijiang series maps (geomorphology map, soil map, vegetation map, land resource map) have been calculated with the method of measuring information by using Entropy function. The result of calculation shows that there are close relations among the natural boundaries, and how to represent the rdat ions is the key problem of the unified harmony. Last, it discusses main measures of ensuring the unified harmony of natural boundaries. The author goes into more details with the reference map of the unified harmony of natural boundaries, which is one of the most important measures. Its contents, compilation and application are described in detail.
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