The Kepler problem and non commutativity

We investigate the Kepler problem using a symplectic structure consistent with the commutation rules of the noncommutative quantum mechanics. We show that a noncommutative parameter of the order of $10^{-58} \text m^2$ gives observable corrections to the movement of the solar system. In this way, modifications in the physics of smaller scales implies modifications at large scales, something similar to the UV/IR mixing.Comment: 10 page

Notas corológicas del macrofitobentos de Andalucía (España). IX

La flora de macroalgas marinas de Andalucía se recoge en los catálogos de Flores-Moya et al. (1995a, 1995b) y Conde et al. (1996a), y en las adiciones posteriores de Conde et al. (1996b), Báez et al. (2001), Altamirano et al. (2006, 2008) e Invernón et al. (2009). En este trabajo, se aportan tres nuevas citas para Andalucía (señaladas con un asterisco), seis citas nuevas para la provincia de Cádiz y una confi rmación para esta provincia. El material recolectado fue identifi cado, y depositado (bien en formol al 4% o bien en pliegos) en el herbario MGC Phyc. Se ha utilizado ALGAEBASE (Guiry & Guiry, 2010) como referencia a la hora de nombrar los diferentes taxones

Supersymmetric Quantum Mechanics, multiphoton algebras and coherent states

The multiphoton algebras for one-dimensional Hamiltonians with infinite discrete spectrum, and for their associated kth-order SUSY partners are studied. In both cases, such an algebra is generated by the multiphoton annihilation and creation operators, as well as by Hamiltonians which are functions of an appropriate number operator. The algebras obtained turn out to be polynomial deformations of the corresponding single-photon algebra previously studied. The Barut-Girardello coherent states, which are eigenstates of the annihilation operator, are obtained and their uncertainty relations are explored by means of the associated quadratures.Comment: Last version of the paper, 6 figure

Noncommutative spaces, the quantum of time and the Lorentz symmetry

We introduce three space-times that are discrete in time and compatible with the Lorentz symmetry. We show that these spaces are no commutative, with commutation relations similar to the relations of the Snyder and Yang spaces. Furthermore, using a reparametrized relativistic particle we obtain a realization of the Snyder type spaces and we construct an action for them.Comment: 8 pages, to appear in PR

Reproducing the cyclic tag system developed by Matthew Cook with Rule 110 using the phases f1_1

This paper implements the cyclic tag system (CTS) in Rule 110 developed by Cook in [1, 2] using regular expressions denominated phases fi_1 [3]. The main problem in CTS is coding the initial condition based in a system of gliders. In this way, we develop a method to control the periodic phases of the strings representing all gliders until now known in Rule 110, including glider guns. These strings form a subset of regular expressions implemented in a computational system to facilitate the construction of CTS. Thus, these phases are useful to establish distances and positions for every glider and then to delineate more sophisticated components or packages of gliders. In this manuscript, it is possible to find differences with the results exposed in Wolfram's book [2], inclusively some mistakes which avoid to obtain an appropriated realization of CTS in Rule 110; fortunately, these irregularities were discussed and clarified by Cook

Determining a regular language by glider-based structures called phases fi_1 in Rule 110

Rule 110 is a complex elementary cellular automaton able of supporting universal computation and complicated collision-based reactions between gliders. We propose a representation for coding initial conditions by means of a finite subset of regular expressions. The sequences are extracted both from de Bruijn diagrams and tiles specifying a set of phases fi_1 for each glider in Rule 110. The subset of regular expressions is explained in detail

Rule 110 objects and other constructions based-collisions

The one-dimensional cellular automaton Rule 110 shows a very ample and diversified glider dynamics. The huge number of collision-based reactions presented in its evolution space are useful to implement some specific (conventional and unconventional) computable process, hence Rule 110 may be used to implement any desired simulation. Therefore there is necessity of defining some interesting objects as: solitons, eaters, black holes, flip-flops, fuses and more. For example, this work explains the construction of meta-gliders; for these constructions, we specify a regular language in Rule 110 to code in detail initial conditions with a required behavior. The paper depicts as well several experimental collision-based constructions

Marine macrophytes and the Water Framework Directive: preliminary studies in southern Spain

The Water Framework Directive (WFD) includes angiosperms and macroalgae as biological quality elements (BQE) for coastal and transitional waters. In southern Spain (Andalusia), studies to implement the WFD using angiosperms (seagrasses) started in June 2009. Different approaches have been considered; the first was the variation of this BQE along an environmental gradient; the second consisted on an extensive sampling campaign in the coastal waters from the western province of Huelva to the eastern province of Almeria. The surveys showed marked differences among the sites and species, indicating a broad variation in the ecological quality values for the water bodies. Additionally, these results will be compared with a similar research conducted on Ria Formosa (Portugal) to provide preliminary classifications of the ecological status of coastal and transitional waters of the southern Iberian Peninsula. With respect to the BQE “macroalgae”, two indices; the CFR (quality of rocky shores) and RSL (reduced species list) have been estimated. The ecological differences between coastal zones in the North Atlantic ecoregion where these methods of assessment have been developed (Northern Spain and the United Kingdom, respectively) and the Atlantic coast of Cadiz, suggested the need for an adaptation of both indices in southern Spain. These extensive surveys have allowed the elaboration of a reduced species list for the rocky shores on the southwestern Spanish Atlantic coasts. The present study shows the preliminary efforts and results of the assessment of BQEs based on marine macrophytes in Southern Spain. Some concerns about the need of reassessment of the proposed tools from the North Atlantic ecoregion when applied to Andalusian water bodies are also discussed.La Directiva Marco de Agua (DMA) incluye como elementos de calidad biológica (BQE) de las aguas de transición y costeras a las angiospermas y macroalgas. En el sur de España (Andalucía), los trabajos para implementar la DMA utilizando angiospermas marinas comenzaron en Junio de 2009. Se han considerado distintas aproximaciones; la primera fue el estudio de los cambios de este BQE a lo largo de un gradiente medioambiental; la segunda consistió en una intensa campaña de muestreo en las aguas costeras desde la provincia más occidental (Huelva) hasta la más oriental (Almería). Las campañas mostraron diferencias notables entre los sitios y las especies, lo que implicó una amplia variación en los valores de calidad ecológica de las masas de agua. Adicionalmente, estos resultados se compararán con un trabajo similar desarrollado en Ria Formosa (Portugal) de forma que se pueda proporcionar una clasificación preliminar del estado ecológico de las aguas costeras y de transición del sur de la Península Ibérica. Con respecto al BQE “macroalgas” se han estimado dos índices: el CFR (calidad de los fondos rocosos) y el RSL (lista reducida de especies). Las diferencias ecológicas entre las zonas costeras de la ecoregión Atlántico Norte donde se han desarrollado estos métodos de evaluación (norte de España y Reino Unido respectivamente) y la costa atlántica de Cádiz, sugirieron la necesidad de una adaptación de ambos índices para el sur de España. Los muestreos intensivos han permitido la elaboración de una lista reducida de especies para las costas rocosas sudoccidentales de España. El presente trabajo muestra los esfuerzos y resultados preliminares de la evaluación de BQEs basados en macrófitos marinos en el sur de España. Se discuten también algunos interrogantes sobre la necesidad de una reevaluación de las herramientas propuestas para la ecorregión Atlántico Norte cuando se aplican a las masas de agua de Andalucía.Universidad de Cádiz. Área de Ecología. Facultad de Ciencias del Mar