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Topological structure of Gauss-Bonnet-Chern theorem and -branes

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Chinese Physics B 2009年第4期18卷 1301-1305页

作者：田苗张欣会段一士 Institute of Theoretical Physics Lanzhou University School of Mathematics Physics and Software Engineering Lanzhou Jiaotong University

By making use of the C-mapping topological current theory, this paper shows that the Gauss Bonnet Chern density （the Euler-Poincare characteristic x（M） density） can be expressed in terms of a smooth vector field φ and take the form of δ（φ）, which means that only the zeros of φ contribute to x（M）. This is the elementary fact of the Hopf theorem. Furthermore, it presents that a new topological tensor current of p-branes can be derived from the Gauss-Bonnet-Chern density. Using this topological current, it obtains the generalized Nambu action for multi p-branes.

关键词： topological structure branes

Instant-Form and Light-Front Hamiltonian and Path Integral Formulations of the Conformally Gauge-Fixed Polyakov D1-Brane Action in the Presence of a Scalar Axion Field and an <i>U</i>(1) Gauge Field

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Journal of Modern Physics 2013年第4期4卷 57-69页

作者： Usha Kulshreshtha Daya S. Kulshreshtha Department of Physics and Astrophysics University of Delhi Delhi India Department of Physics Kirori Mal College University of Delhi Delhi India.

Recently we have studied the instant-form quantization (IFQ) and the light-front quantization (LFQ) of the conformally gauge-fixed Polyakov D1 brane action using the Hamiltonian and path integral formulations. The IFQ is studied in the equal world-sheet time framework on the hyperplanes defined by the world-sheet time σ0=τ=constant and the LFQ in the equal light-cone world-sheet time framework, on the hyperplanes of the light-front defined by the light-cone world-sheet time σ+= (τ+σ) =constant. The light-front theory is seen to be a constrained system in the sense of Dirac in contrast to the instant-form theory. However, owing to the gauge anomalous nature of these theories, both of these theories are seen to lack the usual string gauge symmetries defined by the world-sheet reparametrization invariance (WSRI) and the Weyl invariance (WI). In the present work we show that these theories when considered in the presence of background gauge fields such as the NSNS 2-form gauge field Bαβ(σ,τ) or in the presence of U(1) gauge field Aα(σ,τ) and the constant scalar axion field C(σ,τ), then they are seen to possess the usual string gauge symmetries (WSRI and WI). In fact, these background gauge fields are seen to behave as the Wess-Zumino or Stueckelberg fields and the terms containing these fields are seen to behave as Wess-Zumino or Stueckelberg terms for these theories.

关键词： Lagrangian and Hamiltonian Approach Hamiltonian Quantization Path Integral Quantization Light-Front Quantization Theory of Quantized Fields Constrained Dynamics D-Brane Actions Polyakov Action Strings and branes String Gauge Symmetry Gauge Field Theories

Can Thermal Input from a Prior Universe Account for Relic Graviton Production and Imply Usage of the Bogomolnyi Inequality, as a Bridge between Brane World Models and Loop Quantum Gravity in Early Universe Conditions?

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Journal of High Energy Physics, Gravitation and Cosmology 2016年第3期2卷 412-431页

作者： Andrew Walcott Beckwith Physics Department College of Physics Chongqing University Huxi Campus Chongqing China

The author uses a low temperature and low entropy pre inflation state to create a bridge between String theory and loop quantum gravity. We use this analysis in lieu of the CMB barrier as of z = 1000 since it is our way to come up with a working model of quintessence scalar fields, which permits relic generation of dark matter and dark energy. Not only referencing this bridge, we do it in such a way as to utilize the low entropy condition which the Brane world model of Randal and Sundrum creates, and to show how it is in common with what Caroll and Chen wrote up in 2005., i.e. when the universe was about 1000 times smaller and 100,000 times younger than today.

关键词： branes Axion Walls Bogomolnyi Inequality Four- and Five-Dimensional Cosmological Constant

Quantum Entanglement on Cosmological Scale

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Journal of Modern Physics 2013年第8期4卷 153-159页

作者： A. Nicolaidis, V. Kiosses Theoretical Physics Department Aristotle University of Thessaloniki Thessaloniki Greece

It has been indicated that relational logic may serve as the common foundation of quantum mechanics and string theory. A relation may be represented by a spinor and the Cartan-Penrose connection of spinor to geometry, allows to abstract geometry as the outcome of entangled relations-spinors. Our approach goes in parallel with Wheeler’s pregeometry, where pregeometry, the stage preceding geometry, is based on a calculus of relations-propositions. With a single spinor related to the null cone of Minkowski space-time, we search for the geometry when we couple a left-handed spinor and a right-handed spinor. We find that a Majorana-type coupling gives rise to the ordinary entanglement, while a Diractype coupling generates an extra dimension with two branes coexisting in the extra dimension. One brane hosts lefthanded particles (our brane), while the other brane hosts right-handed particles. A distinct phenomenology accompanies our proposal. The left-right symmetry is achieved with having two “mirror” branes and the neutrino appears as the ideal mediator between the branes. We may revisit also the dark matter, dark energy issues, with everything on the other brane and in the bulk appearing “dark” to us. During the brane collision all points are causally connected, making less pressing the inflationary scenario. Our scheme brings closer logic—quantum theory—cosmology, while space-time, rather than an abstract and an a priori construction, appears as the outcome of a quantum logical act.

关键词： Quantum Entanglement Wheeler’s Pregeometry Cartan-Penrose Spinors Mirror branes Neutrino Oscillations

Does a Randall-Sundrum Brane World Effective Potential Influence Axion Walls Helping to Form a Cosmological Constant Affecting Inflation?

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Journal of High Energy Physics, Gravitation and Cosmology 2016年第1期2卷 125-153页

作者： Andrew Walcott Beckwith Chongqing University Huxi Campus Chongqing China

In 2003, Guth posed the following question in a KITP seminar in UCSB. Namely “Even if there exist 101000 vacuum states produced by String theory, does inflation produce overwhelmingly one preferred type of vacuum states over the other possible types of vacuum states”? This document tries to answer how a preferred vacuum state could be produced, and by what sort of process. We construct a di quark condensate leading to a cosmological constant in line with known physical observations. We use a phase transition bridge from a tilted washboard potential to the chaotic inflationary model pioneered by Guth which is congruent with the slow roll criteria. This permits criteria for initiation of graviton production from a domain wall formed after a transition to a chaotic inflationary potential. It also permits investigation of if or not axion wall contributions to inflation are necessary. If we reject an explicit axion mass drop off to infinitesimal values at high temperatures, we may use the Bogomolnyi inequality to rescale and reset initial conditions for the chaotic inflationary potential. Then the Randall-Sundrum brane world effective potential delineates the end of the dominant role of di quarks, and the beginning of inflation. And perhaps answers Freeman Dysons contention that Graviton production is unlikely given present astrophysical constraints upon detector systems. We end this with a description in the last appendix entry, Appendix VI, as to why, given the emphasis upon di quarks, as to the usefulness of using times before Planck time interval as to modeling our physical system and its importance as to emergent field structures used for cosmological modeling.

关键词： branes Axion Walls Bogomolnyi Inequality Four- and Five-Dimensional Cosmological Constant

Biology-Physics the Missing Link?

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Journal of Modern Physics 2014年第6期5卷 359-363页

作者： Jean-Paul Auffray Ex Courant Institute of Mathematical Sciences New York UniversityNew YorkUSA Ex American Institute of Physics New YorkUSA

Writing in 1943, renowned Austrian physicist Edwin Schrodinger asked “What is Life?” thereby invigorating the debate which preoccupied biologists at the time. He proposed an answer to this question rooted in considerations borrowed from Thermodynamics and Statistical Mechanics. To reveal the missing link in Biology-Physics, the present Note investigates an alternate answer in which dynamical action, rather than thermodynamics and energy, plays the fundamental role. It reviews in particular the process of biological cell replication which may be considered to define “Life” and might be the macroscopic manifestation of an underlying quantum physical process in which xons, conveyors of dynamical action, are the determining agents.

关键词： Schrodinger Dynamical Action Planck Quantum Physics Biological Cells Molecules Electrons Strings branes Xons