The measured 95.5% dark energy density of the cosmos presumed to be behind the observed accelerated cosmic expansion is determined theoretically based upon Witten’s five branes in eleven dimensions theory. We show th...The measured 95.5% dark energy density of the cosmos presumed to be behind the observed accelerated cosmic expansion is determined theoretically based upon Witten’s five branes in eleven dimensions theory. We show that the said dark energy density is easily found from the ratio of the 462 states of the five dimensional Branes to the total number of states, namely 528 minus the 44 degrees of freedom of the vacuum, i.e. , almost exactly as found in WMAP and Type 1a supernova measurements.展开更多
The gravity coupling of the symmetric space sigma model is studied in the solvable Lie algebra parametrization. The corresponding Einstein equations are derived and the energy-momentum tensor is calculated. The result...The gravity coupling of the symmetric space sigma model is studied in the solvable Lie algebra parametrization. The corresponding Einstein equations are derived and the energy-momentum tensor is calculated. The results are used to derive the dynamical equations of the warped five-dimensional (5D) geometry for localized bulk scalar interactions in the framework of thick brane world models. The Einstein and scalar field equations are derived for flat brane geometry in the context of minimal and non-minimal gravity-bulk scalar couplings.展开更多
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 ...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.展开更多
We investigate the construction of four-family N= 1 supersymmetric Pati-Salam models from Type IIA T^(6)×Z_(2) Z_(2) orientifold with intersecting D6-branes. Utilizing the deterministic algorithm introduced in He...We investigate the construction of four-family N= 1 supersymmetric Pati-Salam models from Type IIA T^(6)×Z_(2) Z_(2) orientifold with intersecting D6-branes. Utilizing the deterministic algorithm introduced in He W, Li T and Sun R(2021 ar Xiv: hep-th/2112.09632), we obtain 274 types of models with three rectangular tori and distinct gauge coupling relations at string scale,while 6 types of models with two rectangular tori and one tilted torus. In both cases, there exists a class of models with gauge coupling unification at string scale. In particular, for the models with two rectangular tori, one tilted torus and gauge coupling unification, the gaugino condensations are allowed, and thus supersymmetry breaking and moduli stabilization are possible for further phenomenological study.展开更多
A series of BaZr0.2Co0.8-χFeχO3-σ materials for oxygen separation were synthesized through a citric and EDTA acid combined complexing method, and their crystal structures, oxygen permeabilities, sintering and seali...A series of BaZr0.2Co0.8-χFeχO3-σ materials for oxygen separation were synthesized through a citric and EDTA acid combined complexing method, and their crystal structures, oxygen permeabilities, sintering and sealing abilities were investigated. The results showed that the cubic perovskite structure was formed for materials in the composition range investigated. Oxygen permeation flux and stability, as well as sintering and sealing abilities of the synthesized materials were increased or improved apparently due to the introduction of zirconium. For example, the oxygen permeation flux reached 0.8 mL/min · cm2 when χ = 0.2 or 0.3 at 950℃, and a stable time-related oxygen permeation flux was found for the BaZr0.2Co0.3Fe0.5O3-σ membrane at 800℃.展开更多
In this work we study a brane world model with variable tension, which gives rise to four-dimensional cosmologies. The brane worlds obtained correspond to E?tv?s branes whose(internal) geometry can be casted as either...In this work we study a brane world model with variable tension, which gives rise to four-dimensional cosmologies. The brane worlds obtained correspond to E?tv?s branes whose(internal) geometry can be casted as either a four-dimensional(A)dS_4 or a standard radiation period cosmology. The matter dominated period is discussed as well.展开更多
We discuss how to generate a dynamical Dp-brane with a topology of R^(p-2)×S^(2) from N D(p-2)-branes with R^(p-2) topology with or without the presence of a constant RR(p+2)-form flux.This extends the previous w...We discuss how to generate a dynamical Dp-brane with a topology of R^(p-2)×S^(2) from N D(p-2)-branes with R^(p-2) topology with or without the presence of a constant RR(p+2)-form flux.This extends the previous work(Chen and Lu 2004 arXiv:hep-th/0405265)of generating a dynamical spherical D2 brane from N DO branes in a constant RR four-form flux to a general p.In particular,dynamically generating a higher dimensional brane from lower dimensional ones does not necessarily need the presence of a relevant RR background flux but needs excess energy,lending support to the spacetime uncertainty principle.The time evolution of the dynamical p-brane for a general p remains the same as for the p=2 case,however there is a class of spatial dependent Dp configurations when p≥3.Some of these spatial-dependent Dp brane configurations and their properties have been discussed previously which can also be obtained from the time-dependent one by euclideanizing the time.Properties of the spatial-dependent solutions and their relations to the corresponding brane-anti brane system are discussed.展开更多
Owing to the special structure of a five-dimensional Elko spinor,its localization on a brane with codimension one becomes completely different from that of a Dirac spinor.By introducing the coupling between the Elko s...Owing to the special structure of a five-dimensional Elko spinor,its localization on a brane with codimension one becomes completely different from that of a Dirac spinor.By introducing the coupling between the Elko spinor and the scalar field that can generate the brane,we have two types of localization mechanism for the five-dimensional Elko spinor zero mode on a brane.One is the Yukawa-type coupling,and the other is the non-minimal coupling.In this study,we investigate the localization of the Elko zero mode on de Sitter and Anti-de Sitter thick branes with the two localization mechanisms,respectively.The results show that both the mechanisms can achieve localization.The forms of the scalar coupling function in both localization mechanisms have similar properties,and they play a similar role in localization.展开更多
In this letter, we report on our trials to remove the instability of black holes in brane world cosmological models consisting of two branes and a bulk. In order to resolve this problem, general types of interaction p...In this letter, we report on our trials to remove the instability of black holes in brane world cosmological models consisting of two branes and a bulk. In order to resolve this problem, general types of interaction potentials were employed. Careful analyses have shown that although the black holes instabilities were removed, a sort of arbitrariness adherent to the motion of the two branes towards each other has taken place leading to an unstable system. Thus, the models seem to us rather paradoxical.展开更多
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 w...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.展开更多
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 sta...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.展开更多
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,...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.展开更多
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...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.展开更多
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 conside...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.展开更多
We calculate the long-range Van der Waals force and the photoelectric cross section in a noncommutative setup. It is argued that non-commutativity effects could not be discerned for the Van der Waals interactions. The...We calculate the long-range Van der Waals force and the photoelectric cross section in a noncommutative setup. It is argued that non-commutativity effects could not be discerned for the Van der Waals interactions. The result for the photoelectric effect shows deviation from the usual commutative one, which in principle can be used to put bounds on the space-space non-commutativity parameter.展开更多
A Fock-Darwin system in noncommutative quantum mechanics is studied. By constructing Heisenberg algebra we obtain the levels on noncommutative space and noncommutative phase space, and give the corrections to the resu...A Fock-Darwin system in noncommutative quantum mechanics is studied. By constructing Heisenberg algebra we obtain the levels on noncommutative space and noncommutative phase space, and give the corrections to the results in usual quantum mechanics. Moreover, to search the difference among the three spaces, the degeneracy is analysed by two ways, the value of ω/ωe and certain algebra realization (SU(2)and SU(1,1)), and some interesting properties in the magnetic field limit are exhibited, such as totally different degeneracy and magic number distribution for the given frequency or mass of a system in strong magnetic field.展开更多
In recent works, a construction was proposed resulting in emergent universes inside black holes. This result can be obtained from a 4D black hole embedded in a 5D spacetime with the fifth dimension compactified on a c...In recent works, a construction was proposed resulting in emergent universes inside black holes. This result can be obtained from a 4D black hole embedded in a 5D spacetime with the fifth dimension compactified on a circle [0, 2] (0 and 2 are identified) such that the two branes are at 0 and 1. In the present work, we study this setup by deriving particles’ equations of motion in the new universes, based on redefining energy and angular momentum. This leads to disappearance of the singularity in centers of black holes in classical General Relativity.展开更多
We study the null bulk geodesic motion in the brane world in which the bulk metric has an un-stabilizedextra spatial dimension. We find that the null bulk geodesic motion as observed on the 3-brane with Z2 symmetry wo...We study the null bulk geodesic motion in the brane world in which the bulk metric has an un-stabilizedextra spatial dimension. We find that the null bulk geodesic motion as observed on the 3-brane with Z2 symmetry wouldbe a timelike geodesic motion even though there exists an extra non-gravitational force in contrast with the case of thestabilized extra spatial dimension. In other words the presence of the extra non-gravitational three would not violate the Z2 symmetry.展开更多
文摘The measured 95.5% dark energy density of the cosmos presumed to be behind the observed accelerated cosmic expansion is determined theoretically based upon Witten’s five branes in eleven dimensions theory. We show that the said dark energy density is easily found from the ratio of the 462 states of the five dimensional Branes to the total number of states, namely 528 minus the 44 degrees of freedom of the vacuum, i.e. , almost exactly as found in WMAP and Type 1a supernova measurements.
文摘The gravity coupling of the symmetric space sigma model is studied in the solvable Lie algebra parametrization. The corresponding Einstein equations are derived and the energy-momentum tensor is calculated. The results are used to derive the dynamical equations of the warped five-dimensional (5D) geometry for localized bulk scalar interactions in the framework of thick brane world models. The Einstein and scalar field equations are derived for flat brane geometry in the context of minimal and non-minimal gravity-bulk scalar couplings.
基金Project supported by the National Natural Science Foundation of China (Grant No 10475034)
文摘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.
基金supported by the National Key Research and Development Program of China Grant No. 2020YFC2201504by the Projects No. 11875062, No. 11947302, and No. 12047 503 supported by the National Natural Science Foundation of China+1 种基金by the Key Research Program of the Chinese Academy of Sciences, Grant NO. XDPB15supported by KIAS Individual Grant PG080701。
文摘We investigate the construction of four-family N= 1 supersymmetric Pati-Salam models from Type IIA T^(6)×Z_(2) Z_(2) orientifold with intersecting D6-branes. Utilizing the deterministic algorithm introduced in He W, Li T and Sun R(2021 ar Xiv: hep-th/2112.09632), we obtain 274 types of models with three rectangular tori and distinct gauge coupling relations at string scale,while 6 types of models with two rectangular tori and one tilted torus. In both cases, there exists a class of models with gauge coupling unification at string scale. In particular, for the models with two rectangular tori, one tilted torus and gauge coupling unification, the gaugino condensations are allowed, and thus supersymmetry breaking and moduli stabilization are possible for further phenomenological study.
基金the National Advanced Materials Committee (Grant No.715-006-0122), the Ministry of Science and Technology of China (Grant No. 1999022401) and the National Natural Science Foundation of China (Grant No. 59789201).
文摘A series of BaZr0.2Co0.8-χFeχO3-σ materials for oxygen separation were synthesized through a citric and EDTA acid combined complexing method, and their crystal structures, oxygen permeabilities, sintering and sealing abilities were investigated. The results showed that the cubic perovskite structure was formed for materials in the composition range investigated. Oxygen permeation flux and stability, as well as sintering and sealing abilities of the synthesized materials were increased or improved apparently due to the introduction of zirconium. For example, the oxygen permeation flux reached 0.8 mL/min · cm2 when χ = 0.2 or 0.3 at 950℃, and a stable time-related oxygen permeation flux was found for the BaZr0.2Co0.3Fe0.5O3-σ membrane at 800℃.
基金founded by FONDECYT Regular under Grant Nos.1151107,1131075,1140296,UNAB DI-735-15/R and DPI20140115
文摘In this work we study a brane world model with variable tension, which gives rise to four-dimensional cosmologies. The brane worlds obtained correspond to E?tv?s branes whose(internal) geometry can be casted as either a four-dimensional(A)dS_4 or a standard radiation period cosmology. The matter dominated period is discussed as well.
基金The author would like to thank J X Lu for fruitful discussion and acknowledge support by a grant from the NNSF of China with Grant No:11775212.
文摘We discuss how to generate a dynamical Dp-brane with a topology of R^(p-2)×S^(2) from N D(p-2)-branes with R^(p-2) topology with or without the presence of a constant RR(p+2)-form flux.This extends the previous work(Chen and Lu 2004 arXiv:hep-th/0405265)of generating a dynamical spherical D2 brane from N DO branes in a constant RR four-form flux to a general p.In particular,dynamically generating a higher dimensional brane from lower dimensional ones does not necessarily need the presence of a relevant RR background flux but needs excess energy,lending support to the spacetime uncertainty principle.The time evolution of the dynamical p-brane for a general p remains the same as for the p=2 case,however there is a class of spatial dependent Dp configurations when p≥3.Some of these spatial-dependent Dp brane configurations and their properties have been discussed previously which can also be obtained from the time-dependent one by euclideanizing the time.Properties of the spatial-dependent solutions and their relations to the corresponding brane-anti brane system are discussed.
基金Supported in part by the National Natural Science Foundation of China (11305095, 11647016, 11705106)the Natural Science Foundation of Shandong Province,China (ZR2013AQ016)the Scientic Research Foundation of Shandong University of Science and Technology for Recruited Talents (2013RCJJ026)
文摘Owing to the special structure of a five-dimensional Elko spinor,its localization on a brane with codimension one becomes completely different from that of a Dirac spinor.By introducing the coupling between the Elko spinor and the scalar field that can generate the brane,we have two types of localization mechanism for the five-dimensional Elko spinor zero mode on a brane.One is the Yukawa-type coupling,and the other is the non-minimal coupling.In this study,we investigate the localization of the Elko zero mode on de Sitter and Anti-de Sitter thick branes with the two localization mechanisms,respectively.The results show that both the mechanisms can achieve localization.The forms of the scalar coupling function in both localization mechanisms have similar properties,and they play a similar role in localization.
文摘In this letter, we report on our trials to remove the instability of black holes in brane world cosmological models consisting of two branes and a bulk. In order to resolve this problem, general types of interaction potentials were employed. Careful analyses have shown that although the black holes instabilities were removed, a sort of arbitrariness adherent to the motion of the two branes towards each other has taken place leading to an unstable system. Thus, the models seem to us rather paradoxical.
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
基金Supported by the National Natural Science Foundation of China under Grant No 10575026.
文摘We calculate the long-range Van der Waals force and the photoelectric cross section in a noncommutative setup. It is argued that non-commutativity effects could not be discerned for the Van der Waals interactions. The result for the photoelectric effect shows deviation from the usual commutative one, which in principle can be used to put bounds on the space-space non-commutativity parameter.
基金Supported by the National Natural Science Foundation of China under Grant No 10575026, and the Natural Science Foundation of Zhejiang Provence under Grant No Y607437.
文摘A Fock-Darwin system in noncommutative quantum mechanics is studied. By constructing Heisenberg algebra we obtain the levels on noncommutative space and noncommutative phase space, and give the corrections to the results in usual quantum mechanics. Moreover, to search the difference among the three spaces, the degeneracy is analysed by two ways, the value of ω/ωe and certain algebra realization (SU(2)and SU(1,1)), and some interesting properties in the magnetic field limit are exhibited, such as totally different degeneracy and magic number distribution for the given frequency or mass of a system in strong magnetic field.
文摘In recent works, a construction was proposed resulting in emergent universes inside black holes. This result can be obtained from a 4D black hole embedded in a 5D spacetime with the fifth dimension compactified on a circle [0, 2] (0 and 2 are identified) such that the two branes are at 0 and 1. In the present work, we study this setup by deriving particles’ equations of motion in the new universes, based on redefining energy and angular momentum. This leads to disappearance of the singularity in centers of black holes in classical General Relativity.
基金The project supported by National Natural Science Foundation of China under Grant No.10175070
National Basic Research Project of China under Grant No.2003CB716300
文摘We study the null bulk geodesic motion in the brane world in which the bulk metric has an un-stabilizedextra spatial dimension. We find that the null bulk geodesic motion as observed on the 3-brane with Z2 symmetry wouldbe a timelike geodesic motion even though there exists an extra non-gravitational force in contrast with the case of thestabilized extra spatial dimension. In other words the presence of the extra non-gravitational three would not violate the Z2 symmetry.