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arXivPseudoperiodic homeomorphisms and degeneration of Riemann surfaces Yukio Matsumoto, José Mariá MontesinosAmilibia 19931231 We will announce two theorems. The first theorem will classify all topological types of degenerate fibers appearing in oneparameter families of Riemann surfaces, in terms of ``pseudoperiodic'' surface homeomorphisms. The second theorem will give a complete set of conjugacy invariants for the mapping classes of such homeomorphisms. This latter result implies that Nielsen's set of invariants [{\it Surface transformation classes of algebraically finite type}, Collected Papers 2, Birkh\"auser (1986)] is not complete.
Subject 수학 Source arXiv URL https://arxiv.org/abs/math/9401223view Article Title Pseudoperiodic homeomorphisms and degeneration of Riemann surfacesAuthors Yukio Matsumoto; José Mariá MontesinosAmilibiaAbstract We will announce two theorems. The first theorem will classify all topological types of degenerate fibers appearing in oneparameter families of Riemann surfaces, in terms of ``pseudoperiodic'' surface homeomorphisms. The second theorem will give a complete set of conjugacy invariants for the mapping classes of such homeomorphisms. This latter result implies that Nielsen's set of invariants [{\it Surface transformation classes of algebraically finite type}, Collected Papers 2, Birkh\"auser (1986)] is not complete.Is Part Of Bull. Amer. Math. Soc. (N.S.) 30 (1994) 7075 19931231 Identifier ISSN: Category math.CVLicense 
arXivThe Projection Postulate of Quantum Mechanics on the Lightcone J. Finkelstein 19931231 We discuss an interpretation of the projection postulate that implies collapse of the wavefunction along the lightcone.
Subject Source arXiv URL https://arxiv.org/abs/hepth/9312211view Article Title The Projection Postulate of Quantum Mechanics on the LightconeAuthors J. FinkelsteinAbstract We discuss an interpretation of the projection postulate that implies collapse of the wavefunction along the lightcone.Is Part Of 19931231 Identifier ISSN: DOI 10.1016/03759601(84)900045Category hepthLicense 
arXivAnomalous Magnetic Properties of Rh$_13$ Clusters Yang Jinlong, F. Toigo, Wang Kelin, ... more(4) 19931231 Electronic structures of 13atom Rh clusters with three possible highsymmetry geometries are studied using the discretevariational localspindensityfunctional method. The ground state is found to be the icosahedral structure, and a total magnetic moment of 15$\mu_B$ is obtained for the cluster. This value is anomalously smaller than those for clusters with lower symmetries, but in agreement with recent experiments. The magnetic interactions between the central and surface atoms of the cluster are {\it not} fully ferromagnetic, and a small amount of antiferromagnetic interactions is found to be mixed in. An energy parameter is introduced to explain the anomalous magnetic properties, which is found to be also useful for judging whether some techniques can or must be used in the localspindensityfunctional calculations.
Subject Source arXiv URL https://arxiv.org/abs/condmat/9312096view Article Title Anomalous Magnetic Properties of Rh$_13$ ClustersAuthors Yang Jinlong; F. Toigo; Wang Kelin; Zhang ManhongAbstract Electronic structures of 13atom Rh clusters with three possible highsymmetry geometries are studied using the discretevariational localspindensityfunctional method. The ground state is found to be the icosahedral structure, and a total magnetic moment of 15$\mu_B$ is obtained for the cluster. This value is anomalously smaller than those for clusters with lower symmetries, but in agreement with recent experiments. The magnetic interactions between the central and surface atoms of the cluster are {\it not} fully ferromagnetic, and a small amount of antiferromagnetic interactions is found to be mixed in. An energy parameter is introduced to explain the anomalous magnetic properties, which is found to be also useful for judging whether some techniques can or must be used in the localspindensityfunctional calculations.Is Part Of 19931231 Identifier ISSN: Category condmatLicense 
arXivTeleoReactive Programs for Agent Control N. Nilsson 19931231 A formalism is presented for computing and organizing actions for autonomous agents in dynamic environments. We introduce the notion of teleoreactive (TR) programs whose execution entails the construction of circuitry for the continuous computation of the parameters and conditions on which agent action is based. In addition to continuous feedback, TR programs support parameter binding and recursion. A primary difference between TR programs and many other circuitbased systems is that the circuitry of TR programs is more compact; it is constructed at run time and thus does not have to anticipate all the contingencies that might arise over all possible runs. In addition, TR programs are intuitive and easy to write and are written in a form that is compatible with automatic planning and learning methods. We briefly describe some experimental applications of TR programs in the control of simulated and actual mobile robots.
Subject Source arXiv URL https://arxiv.org/abs/cs/9401101view Article Title TeleoReactive Programs for Agent ControlAuthors N. NilssonAbstract A formalism is presented for computing and organizing actions for autonomous agents in dynamic environments. We introduce the notion of teleoreactive (TR) programs whose execution entails the construction of circuitry for the continuous computation of the parameters and conditions on which agent action is based. In addition to continuous feedback, TR programs support parameter binding and recursion. A primary difference between TR programs and many other circuitbased systems is that the circuitry of TR programs is more compact; it is constructed at run time and thus does not have to anticipate all the contingencies that might arise over all possible runs. In addition, TR programs are intuitive and easy to write and are written in a form that is compatible with automatic planning and learning methods. We briefly describe some experimental applications of TR programs in the control of simulated and actual mobile robots.Is Part Of Journal of Artificial Intelligence Research, Vol 1, (1994), 139158 19931231 Identifier ISSN: Category cs.AILicense 
arXivGeneralized KazakovMigdalKontsevich Model: group theory aspects S. Kharchev, A. Marshakov, A. Mironov, ... more(4) 19931231 The KazakovMigdal model, if considered as a functional of external fields, can be always represented as an expansion over characters of $GL$ group. The integration over "matter fields" can be interpreted as going over the {\it model} (the space of all highest weight representations) of $GL$. In the case of compact unitary groups the integrals should be substituted by {\it discrete} sums over weight lattice. The $D=0$ version of the model is the Generalized Kontsevich integral, which in the abovementioned unitary (discrete) situation coincides with partition function of the $2d$ YangMills theory with the target space of genus $g=0$ and $m=0,1,2$ holes. This particular quantity is always a bilinear combination of characters and appears to be a Todalattice $\tau$function. (This is generalization of the classical statement that individual $GL$ characters are always singular KP $\tau$functions.) The corresponding element of the Universal Grassmannian is very simple and somewhat similar to the one, arising in investigations of the $c=1$ string models. However, under certain circumstances the formal sum over representations should be evaluated by steepest descent method and this procedure leads to some more complicated elements of Grassmannian. This "Kontsevich phase" as opposed to the simple "character phase" deserves further investigation.
Subject Source arXiv URL https://arxiv.org/abs/hepth/9312210view Article Title Generalized KazakovMigdalKontsevich Model: group theory aspectsAuthors S. Kharchev; A. Marshakov; A. Mironov; A. MorozovAbstract The KazakovMigdal model, if considered as a functional of external fields, can be always represented as an expansion over characters of $GL$ group. The integration over "matter fields" can be interpreted as going over the {\it model} (the space of all highest weight representations) of $GL$. In the case of compact unitary groups the integrals should be substituted by {\it discrete} sums over weight lattice. The $D=0$ version of the model is the Generalized Kontsevich integral, which in the abovementioned unitary (discrete) situation coincides with partition function of the $2d$ YangMills theory with the target space of genus $g=0$ and $m=0,1,2$ holes. This particular quantity is always a bilinear combination of characters and appears to be a Todalattice $\tau$function. (This is generalization of the classical statement that individual $GL$ characters are always singular KP $\tau$functions.) The corresponding element of the Universal Grassmannian is very simple and somewhat similar to the one, arising in investigations of the $c=1$ string models. However, under certain circumstances the formal sum over representations should be evaluated by steepest descent method and this procedure leads to some more complicated elements of Grassmannian. This "Kontsevich phase" as opposed to the simple "character phase" deserves further investigation.Is Part Of Int. J. Mod. Phys. A10 (1995) 2015 19931231 Identifier ISSN: DOI 10.1142/S0217751X9500098XCategory hepth nlin.SI solvintLicense 
arXivOn the Motion of Heavy Quarks inside Hadrons: Universal Distributions and Inclusive Decays I. I. Bigi, M. A. Shifman, N. G. Uraltsev, ... more(4) 19931231 In previous papers we have pointed out that there exists a QCD analog of the phenomenological concept of the so called Fermi motion for the heavy quark inside a hadron. Here we show in a more detailed way how this comes about and we analyze the limitations of this concept. Nonperturbative as well as perturbative aspects are included. We emphasize both the similarities and the differences to the wellknown treatment of deep inelastic leptonnucleon scattering. We derive a modelindependent {\em lower} bound on the kinetic energy of the heavy quark inside the hadron.
Subject Source arXiv URL https://arxiv.org/abs/hepph/9312359view Article Title On the Motion of Heavy Quarks inside Hadrons: Universal Distributions and Inclusive DecaysAuthors I. I. Bigi; M. A. Shifman; N. G. Uraltsev; A. I. VainshteinAbstract In previous papers we have pointed out that there exists a QCD analog of the phenomenological concept of the so called Fermi motion for the heavy quark inside a hadron. Here we show in a more detailed way how this comes about and we analyze the limitations of this concept. Nonperturbative as well as perturbative aspects are included. We emphasize both the similarities and the differences to the wellknown treatment of deep inelastic leptonnucleon scattering. We derive a modelindependent {\em lower} bound on the kinetic energy of the heavy quark inside the hadron.Is Part Of Int.J.Mod.Phys. A9 (1994) 24672504 19931231 Identifier ISSN: DOI 10.1142/S0217751X94000996Category hepphLicense 
arXivRadiative Corrections to $\zbb$ from Colored Scalars in a Model with Dynamical Symmetry Breaking A. Kundu, S. Raychaudhuri, T. De, ... more(4) 19931231 Isodoublet coloroctet scalar bosons appear in the lowenergy limit of a natural extension of the Standard Model in which the electroweak symmetry is broken by a $t\bar t$ condensate. We briefly discuss the model and show that radiative corrections (involving these scalars) to the branching ratio $R_b=\Gamma (Z\rightarrow b\bar b)/\Gamma (Z\rightarrow {\rm hadrons})$ are negative and thus place a stringent lower bound on the masses of the colored scalars. This turns out to be $\sim 400$ GeV with $m_t=150$ GeV and increases quadratically with $m_t$. It is emphasized that $R_b$ is a parameter that is welldetermined experimentally and that theoretical estimates are relatively free from uncertainties emanating from hadronic corrections and are comparatively insensitive to the value of the top mass.
Subject Source arXiv URL https://arxiv.org/abs/hepph/9312361view Article Title Radiative Corrections to $\zbb$ from Colored Scalars in a Model with Dynamical Symmetry BreakingAuthors A. Kundu; S. Raychaudhuri; T. De; B. DuttaRoyAbstract Isodoublet coloroctet scalar bosons appear in the lowenergy limit of a natural extension of the Standard Model in which the electroweak symmetry is broken by a $t\bar t$ condensate. We briefly discuss the model and show that radiative corrections (involving these scalars) to the branching ratio $R_b=\Gamma (Z\rightarrow b\bar b)/\Gamma (Z\rightarrow {\rm hadrons})$ are negative and thus place a stringent lower bound on the masses of the colored scalars. This turns out to be $\sim 400$ GeV with $m_t=150$ GeV and increases quadratically with $m_t$. It is emphasized that $R_b$ is a parameter that is welldetermined experimentally and that theoretical estimates are relatively free from uncertainties emanating from hadronic corrections and are comparatively insensitive to the value of the top mass.Is Part Of Phys.Rev. D50 (1994) 68726876 19931231 Identifier ISSN: DOI 10.1103/PhysRevD.50.6872Category hepphLicense 
arXivThe representations of TemperleyLiebJones algebras R. K. Kaul 19931231 Representations of braid group obtained from rational conformal field theories can be used to obtain explicit representations of TemperleyLiebJones algebras. The method is described in detail for SU(2)$_k$ Wess  Zumino conformal field theories and its generalization to an arbitrary rational conformal field theory outlined. Explicit definition of an associated linear trace operation in terms of a certain matrix element in the space of conformal blocks of such a conformal theory is presented. Further for every primary field of a rational conformal field theory, there is a subfactor of hyperfinite II$_1$ factor with trivial relative commutant. The index of the subfactor is given in terms of identity  identity element of certain duality matrix for conformal blocks of fourpoint correlators. Jones formula for index ( $<$ 4 ) for subfactors corresponds to spin ${\frac{1}{2}}$ representation of SU(2)$_k$ WessZumino conformal field theory. Definition of the trace operation also provides a method of obtaining link invariants explicitly.
Subject 수학 Source arXiv URL https://arxiv.org/abs/hepth/9312214view Article Title The representations of TemperleyLiebJones algebrasAuthors R. K. KaulAbstract Representations of braid group obtained from rational conformal field theories can be used to obtain explicit representations of TemperleyLiebJones algebras. The method is described in detail for SU(2)$_k$ Wess  Zumino conformal field theories and its generalization to an arbitrary rational conformal field theory outlined. Explicit definition of an associated linear trace operation in terms of a certain matrix element in the space of conformal blocks of such a conformal theory is presented. Further for every primary field of a rational conformal field theory, there is a subfactor of hyperfinite II$_1$ factor with trivial relative commutant. The index of the subfactor is given in terms of identity  identity element of certain duality matrix for conformal blocks of fourpoint correlators. Jones formula for index ( $<$ 4 ) for subfactors corresponds to spin ${\frac{1}{2}}$ representation of SU(2)$_k$ WessZumino conformal field theory. Definition of the trace operation also provides a method of obtaining link invariants explicitly.Is Part Of Nucl.Phys. B417 (1994) 267288 19931231 Identifier ISSN: DOI 10.1016/05503213(94)905479Category hepth math.QALicense 
arXivTesting Gluon SelfInteractions in Three Jet Events at Hadron Colliders L. Dixon, Y. Shadmi 19931231 The effective operator tr(G^3) is the only dimension6 gluonic operator that cannot be related to fourquark operators. A peculiar property of this operator is that it does not contribute to twojet production at hadron colliders, at the level of one operator insertion and leadingorder in alpha_s; therefore we study its effects on three jet events. To calculate the helicity amplitudes induced by this operator we make extensive use of collinear factorization. We propose several ways of detecting the tr(G^3) signal, one of which exploits its nontrivial behavior under azimuthal rotations of two almost collinear jets.
Subject Source arXiv URL https://arxiv.org/abs/hepph/9312363view Article Title Testing Gluon SelfInteractions in Three Jet Events at Hadron CollidersAuthors L. Dixon; Y. ShadmiAbstract The effective operator tr(G^3) is the only dimension6 gluonic operator that cannot be related to fourquark operators. A peculiar property of this operator is that it does not contribute to twojet production at hadron colliders, at the level of one operator insertion and leadingorder in alpha_s; therefore we study its effects on three jet events. To calculate the helicity amplitudes induced by this operator we make extensive use of collinear factorization. We propose several ways of detecting the tr(G^3) signal, one of which exploits its nontrivial behavior under azimuthal rotations of two almost collinear jets.Is Part Of Nucl.Phys.B423:332,1994; ERRATUMibid.B452:724,1995 19931231 Identifier ISSN: DOI 10.1016/05503213(94)905630Category hepphLicense 
arXivOn a cnumber quantum $\tau$function A. Mironov, A. Morozov, L. Vinet... more(3) 19931231 We first review the properties of the conventional $\tau$functions of the KP and Todalattice hierarchies. A straightforward generalization is then discussed. It corresponds to passing from differential to finitedifference equations; it does not involve however the concept of operatorvalued $\tau$function nor the one associated with nonCartanian (level $k\ne1$) algebras. The present study could be useful to understand better $q$free fields and their relation to ordinary free fields.
Subject Source arXiv URL https://arxiv.org/abs/hepth/9312213view Article Title On a cnumber quantum $\tau$functionAuthors A. Mironov; A. Morozov; L. VinetAbstract We first review the properties of the conventional $\tau$functions of the KP and Todalattice hierarchies. A straightforward generalization is then discussed. It corresponds to passing from differential to finitedifference equations; it does not involve however the concept of operatorvalued $\tau$function nor the one associated with nonCartanian (level $k\ne1$) algebras. The present study could be useful to understand better $q$free fields and their relation to ordinary free fields.Is Part Of Theor.Math.Phys.100:890899,1995; Teor.Mat.Fiz.100:119131,1994 19931231 Identifier ISSN: DOI 10.1007/BF01017328Category hepth nlin.SI solvintLicense