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Sep 21, 2013
09/13

by
A. P. Balachandran

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We review certain emergent notions on the nature of spacetime from noncommutative geometry and their radical implications. These ideas of spacetime are suggested from developments in fuzzy physics, string theory, and deformation quantisation. The review focuses on the ideas coming from fuzzy physics. We find models of quantum spacetime like fuzzy $S^4$ on which states cannot be localised, but which fluctuate into other manifolds like $ CP^3$ . New uncertainty principles concerning such lack of...

Source: http://arxiv.org/abs/hep-th/0203259v3

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Sep 19, 2013
09/13

by
A. P. Balachandran

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This article, written in honor of Fritz Rohrlich, briefly surveys the role of topology in physics.

Source: http://arxiv.org/abs/hep-th/9303177v1

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Jul 20, 2013
07/13

by
A. P. Balachandran

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Any two infinite-dimensional (separable) Hilbert spaces are unitarily isomorphic. The sets of all their self-adjoint operators are also therefore unitarily equivalent. Thus if all self-adjoint operators can be observed, and if there is no further major axiom in quantum physics than those formulated for example in Dirac's `Quantum Mechanics', then a quantum physicist would not be able to tell a torus from a hole in the ground. We argue that there are indeed such axioms involving vectors in the...

Source: http://arxiv.org/abs/quant-ph/9702055v2

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Jul 19, 2013
07/13

by
A. P. Balachandran

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The following two loosely connected sets of topics are reviewed in these lecture notes: 1) Gauge invariance, its treatment in field theories and its implications for internal symmetries and edge states such as those in the quantum Hall effect. 2) Quantisation on multiply connected spaces and a topological proof the spin-statistics theorem which avoids quantum field theory and relativity. Under 1), after explaining the meaning of gauge invariance and the theory of constraints, we discuss...

Source: http://arxiv.org/abs/hep-th/9210111v1

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Sep 18, 2013
09/13

by
A. P. Balachandran

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Any two infinite-dimensional (separable) Hilbert spaces are unitarily isomorphic. The sets of all their self-adjoint operators are also therefore unitarily equivalent. Thus if all self-adjoint operators can be observed, and if there is no further major axiom in quantum physics than those formulated for example in Dirac's `Quantum Mechanics', then a quantum physicist would not be able to tell a torus from a hole in the ground. We argue that there are indeed such axioms involving observables with...

Source: http://arxiv.org/abs/quant-ph/0002055v2

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8.0

Jun 28, 2018
06/18

by
A. P. Balachandran

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In a previous work [1], we have argued that the algebra of non-abelian superselection rules is spontaneously broken to its maximal abelian subalgebra, that is, the algebra generated by its completing commuting set (the two Casimirs and a basis of its Cartan subalgebra). In this paper, alternative arguments confirming these results are presented. In addition, Lorentz invariance is shown to be broken in QCD, just as it is in QED. The experimental consequences of these results include fuzzy mass...

Topics: Mathematical Physics, Mathematics, High Energy Physics - Theory

Source: http://arxiv.org/abs/1509.05235

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Sep 19, 2013
09/13

by
A. P. Balachandran

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Meghnad Saha occupies a special role in the history of Indian science, having been a pioneer in its organization already from the oppressive colonial period and having left important legacies to post-colonial India like the Saha Institute of Nuclear Physics. He is famous for his research in astrophysics, and has also made important, but less well-known contributions to magnetic monopole theory. This article attempts an elementary survey of this theory and its implications with special emphasis...

Source: http://arxiv.org/abs/hep-ph/9303312v1

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Sep 22, 2013
09/13

by
A. P. Balachandran; S. Kurkcuoglu

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Fuzzy spaces are obtained by quantizing adjoint orbits of compact semi-simple Lie groups. Fuzzy spheres emerge from quantizing S^2 and are associated with the group SU(2) in this manner. They are useful for regularizing quantum field theories and modeling spacetimes by non-commutative manifolds. We show that fuzzy spaces are Hopf algebras and in fact have more structure than the latter. They are thus candidates for quantum symmetries. Using their generalized Hopf algebraic structures, we can...

Source: http://arxiv.org/abs/hep-th/0310026v4

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Sep 22, 2013
09/13

by
A. P. Balachandran; Pramod Padmanabhan

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Quantum theories constructed on the noncommutative spacetime called the Groenewold-Moyal(GM) plane exhibit many interesting properties such as causality violation, Lorentz and CPT non-invariance and twisted statistics. Such violations lead to many striking features that may be tested experimentally. Thus these theories predict Pauli-forbidden transitions due to twisted statistics, anisotropies and acausal effects in the cosmic microwave background radiation in correlations of observables and...

Source: http://arxiv.org/abs/0908.3888v1

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Sep 23, 2013
09/13

by
A. P. Balachandran; Giorgio Immirzi

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Nonlinear `sigma' models in two dimensions have BPS solitons which are solutions of self- and anti-self-duality constraints. In this paper, we find their analogues for fuzzy sigma models on fuzzy spheres which were treated in detail by us in earlier work. We show that fuzzy BPS solitons are quantized versions of `Bott projectors', and construct them explicitly. Their supersymmetric versions follow from the work of S. Kurkcuoglu.

Source: http://arxiv.org/abs/hep-th/0408111v2

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2.0

Jun 30, 2018
06/18

by
Nirmalendu Acharyya; A. P. Balachandran

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In a matrix model of pure $SU(2)$ Yang-Mills theory, boundaries emerge in the space of $\textrm{Mat}_{3}(\mathbb{R})$ and the Hamiltonian requires boundary conditions. We show the existence of edge localized glueball states which can have negative energies. These edge levels can be lifted to positive energies if the gluons acquire a London-like mass. This suggests a new phase of QCD with an incompressible bulk.

Topics: High Energy Physics - Theory, High Energy Physics - Phenomenology, Mathematical Physics, Mathematics

Source: http://arxiv.org/abs/1702.06430

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Jun 29, 2018
06/18

by
A P Balachandran; Babar Qureshi

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In QED and QCD [1, 2], infrared photons and gluons alter the Hilbert space of the theory so that the in and out states live in a Hilbert space carrying a representation of basic commutation relations which is non-equivalent to the standard Fock representation, leading to spontaneous breakdown of Lorentz symmetry and physical effects. These results are generalized here to quantum gravity regarded as an SL(2; C) gauge theory and the shift of the ADM energy density and mass from infrared spin...

Topics: High Energy Physics - Theory, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1601.07370

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Sep 22, 2013
09/13

by
G. Alexanian; A. P. Balachandran

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Many years ago Friedman and Sorkin [1] established the existence of certain topological solitonic excitations in quantum gravity called (topological) geons. Geons can have quantum numbers like charge and can be tensorial or spinorial having integer or half-odd integer spin. A striking result is that geons can violate the canonical spin-statistics connection [2,3]. Such violation induces novel physical effects at low energies. The latter will be small since the geon mass is expected to be of the...

Source: http://arxiv.org/abs/hep-th/0111039v3

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Sep 18, 2013
09/13

by
A. P. Balachandran; S. Vaidya

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It is well-known that the winding number of the Skyrmion can be identified as the baryon number. We show in this paper that this result can also be established using the Atiyah-Singer index theorem and spectral flow arguments. We argue that this proof suggests that there are light quarks moving in the field of the Skyrmion. We then show that if these light degrees of freedom are averaged out, the low energy excitations of the Skyrmion are in fact spinorial. A natural consequence of our approach...

Source: http://arxiv.org/abs/hep-th/9803125v1

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Sep 20, 2013
09/13

by
A. P. Balachandran; G. Immirzi

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The Ginsparg-Wilson algebra is the algebra underlying the Ginsparg-Wilson solution of the fermion doubling problem in lattice gauge theory. The Dirac operator of the fuzzy sphere is not afflicted with this problem. Previously we have indicated that there is a Ginsparg-Wilson operator underlying it as well in the absence of gauge fields and instantons. Here we develop this observation systematically and establish a Dirac operator theory for the fuzzy sphere with or without gauge fields, and...

Source: http://arxiv.org/abs/hep-th/0301242v2

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97

Jul 20, 2013
07/13

by
A. P. Balachandran; S. Vaidya

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In continuum physics, there are important topological aspects like instantons, theta-terms and the axial anomaly. Conventional lattice discretizations often have difficulties in treating one or the other of these aspects. In this paper, we develop discrete quantum field theories on fuzzy manifolds using noncommutative geometry. Basing ourselves on previous treatments of instantons and chiral fermions (without fermion doubling) on fuzzy spaces and especially fuzzy spheres, we present discrete...

Source: http://arxiv.org/abs/hep-th/9910129v2

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Sep 22, 2013
09/13

by
A. P. Balachandran; S. Vaidya

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Frohlich, Morchio and Strocchi long ago proved that Lorentz invariance is spontaneously broken in QED because of infrared effects. We develop a simple model where consequences of this breakdown can be explicitly and easily calculated. For this purpose, the superselected U(1) charge group of QED is extended to a superselected "Sky" group containing direction-dependent gauge transformations at infinity. It is the analog of the Spi group of gravity. As Lorentz transformations do not...

Source: http://arxiv.org/abs/1302.3406v2

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Sep 20, 2013
09/13

by
A. P. Balachandran; S. Digal

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Non-abelian (NA) topological string defects exist in QCD with the spontaneous chiral symmetry breaking $U(N_f)_L \times U(N_f)_R \to U(N_f)_V$. Anomaly effects lead to domain walls connected to these strings. In the framework of linear sigma model we find the configuration of these defects. Also we show that in this model metastable CP violating vacuua exist. Strings as well as extended regions of metastable vacuua may form during the chiral transition which could have interesting effects.

Source: http://arxiv.org/abs/hep-ph/0204262v1

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Sep 21, 2013
09/13

by
A. P. Balachandran; L. Chandar

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't Hooft has recently developed a discretisation of (2+1) gravity which has a multiple-valued Hamiltonian and which therefore admits quantum time evolution only in discrete steps. In this paper, we describe several models in the continuum with single-valued equations of motion in classical physics, but with multiple-valued Hamiltonians. Their time displacements in quantum theory are therefore obliged to be discrete. Classical models on smooth spatial manifolds are also constructed with the...

Source: http://arxiv.org/abs/hep-th/9404193v2

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Sep 18, 2013
09/13

by
A. P. Balachandran; G. Immirzi

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In spacetime dimensions larger than 2, whenever a global symmetry G is spontaneously broken to a subgroup H, and G and H are Lie groups, there are Nambu-Goldstone modes described by fields with values in G/H. In two-dimensional spacetimes as well, models where fields take values in G/H are of considerable interest even though in that case there is no spontaneous breaking of continuous symmetries. We consider such models when the world sheet is a two-sphere and describe their fuzzy analogues for...

Source: http://arxiv.org/abs/hep-th/0212133v2

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Sep 21, 2013
09/13

by
A. P. Balachandran; M. Martone

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The Moyal and Wick-Voros planes A^{M,V}_{\theta} are *-isomorphic. On each of these planes the Poincar\'e group acts as a Hopf algebra symmetry if its coproducts are deformed by twist factors. We show that the *-isomorphism T: A^M_{\theta} to A^V_{\theta} does not also map the corresponding twists of the Poincar\'e group algebra. The quantum field theories on these planes with twisted Poincar\'e-Hopf symmetries are thus inequivalent. We explicitly verify this result by showing that a...

Source: http://arxiv.org/abs/0902.1247v4

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Sep 20, 2013
09/13

by
A. P. Balachandran; A. Pinzul

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We explore the consequences of time-space noncommutativity in the quantum mechanics of atoms and molecules, focusing on the Moyal plane with just time-space noncommutativity ($[\hat{x}_\mu ,\hat{x}_\nu]=i\theta_{\mu\nu}$, $\theta_{0i}\neqq 0$, $\theta_{ij}=0$). Space rotations and parity are not automorphisms of this algebra and are not symmetries of quantum physics. Still, when there are spectral degeneracies of a time-independent Hamiltonian on a commutative space-time which are due to...

Source: http://arxiv.org/abs/hep-th/0410199v2

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Sep 17, 2013
09/13

by
A. P. Balachandran; S. Digal

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We extend and generalize the seminal work of Brandenberger, Huang and Zhang on the formation of strings during chiral phase transitions(berger) and discuss the formation of abelian and non-abelian topological strings during such transitions in the early Universe and in the high energy heavy-ion collisions. Chiral symmetry as well as deconfinement are restored in the core of these defects. Formation of a dense network of string defects is likely to play an important role in the dynamics...

Source: http://arxiv.org/abs/hep-ph/0108086v3

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Sep 23, 2013
09/13

by
A. P. Balachandran; Pramod Padmanabhan

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Noncommutative spacetimes lead to nonlocal quantum field theories (qft's) where spin-statistics theorems cannot be proved. For this reason, and also backed by detailed arguments, it has been suggested that they get corrected on such spacetimes leading to small violations of the Pauli principle. In a recent paper \cite{Pauli}, Pauli-forbidden transitions from spacetime noncommutativity were calculated and confronted with experiments. Here we give details of the computation missing from this...

Source: http://arxiv.org/abs/1006.1185v2

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Sep 21, 2013
09/13

by
A. P. Balachandran; M. Martone

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We show how to get a non-commutative product for functions on space-time starting from the deformation of the coproduct of the Poincare' group using the Drinfel'd twist. Thus it is easy to see that the commutative algebra of functions on space-time (R^4) can be identified as the set of functions on the Poincare' group invariant under the right action of the Lorentz group provided we use the standard coproduct for the Poincare' group. We obtain our results for the noncommutative Moyal plane by...

Source: http://arxiv.org/abs/0902.3409v2

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Sep 18, 2013
09/13

by
A. P. Balachandran; S. Vaidya

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There are numerous examples of very nearly degenerate states of opposite parity in molecular physics. The ammonia maser is based on one such double. Theory shows that these parity doubles can occur if the nuclear shape in the molecule is reflection-asymmetric because the time scales of the shape and the electronic cloud are well-separated. Parity doubles occur in nuclear physics as well for odd $A \sim 219-229$. We discuss the theoretical foundation of these doubles and on that basis suggest...

Source: http://arxiv.org/abs/hep-ph/9606283v3

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Sep 22, 2013
09/13

by
A. P. Balachandran; S. Vaidya

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There are numerous examples of approximately degenerate states of opposite parity in molecular physics. Theory indicates that these doubles can occur in molecules that are reflection-asymmetric. Such parity doubles occur in nuclear physics as well, among nuclei with odd A $\sim$ 219-229. We have also suggested elsewhere that such doubles occur in particle physics for baryons made up of `cbu' and `cbd' quarks. In this article, we discuss the theoretical foundations of these doubles in detail,...

Source: http://arxiv.org/abs/hep-th/9612053v2

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Sep 21, 2013
09/13

by
A. P. Balachandran; P. Teotonio-Sobrinho

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Let $B$ and $F=\frac 12F_{\mu \nu}dx^\mu \wedge dx^\nu $ be two forms, $F_{\mu \nu}$ being the field strength of an abelian connection $A$. The topological $BF$ system is given by the integral of $B\wedge F$. With "kinetic energy'' terms added for $B$ and $A$, it generates a mass for $A$ thereby suggesting an alternative to the Higgs mechanism, and also gives the London equations. The $BF$ action, being the large length and time scale limit of this augmented action, is thus of physical...

Source: http://arxiv.org/abs/hep-th/9304067v2

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Sep 23, 2013
09/13

by
A. P. Balachandran; B. A. Qureshi

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In previous work, starting from the Moyal plane, we formulated interacting theories of matter and gauge fields with only the former fields twisted. In this approach, gauge theories, including the standard model, can be formulated without new gauge degrees of freedom. We show their underlying symmetry algebra to be Poincar\'e quasi-Hopf . The associated spacetime algebra is hence non-associative.

Source: http://arxiv.org/abs/0903.0478v3

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Sep 23, 2013
09/13

by
A. P. Balachandran; S. M. Roy

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We establish an exact differential equation for the operator describing time-dependent measurements continuous in time and obtain a series solution. Suppose the projection operator $E(t) = U(t) E U^\dagger(t)$ is measured continuously from t = 0 to T, where E is a projector leaving the initial state unchanged and U(t) a unitary operator obeying U(0) = 1 and some smoothness conditions in t. We prove that the probability of always finding E(t) = 1 from t = 0 to T is unity. If $U(t) \neq 1$, the...

Source: http://arxiv.org/abs/quant-ph/9909056v1

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Sep 18, 2013
09/13

by
A. P. Balachandran; S. G. Jo

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Yang's theorem forbids the process $Z^0 \to 2\gamma$ in any Poincar\'{e} invariant theory if photons are bosons and their two-particle states transform under the Poincar\'{e} group in the standard way (under the standard coproduct of the Poincar\'{e} group). This is an important result as it does not depend on the assumptions of quantum field theory. Recent work on noncommutative geometry requires deforming the above coproduct by the Drinfel'd twist. We prove that $Z^0 \to 2\gamma$ is forbidden...

Source: http://arxiv.org/abs/0704.0921v5

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Sep 21, 2013
09/13

by
A. P. Balachandran; P. Teotonio-Sobrinho

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It is known that the 3d Chern-Simons interaction describes the scaling limit of a quantum Hall system and predicts edge currents in a sample with boundary, the currents generating a chiral $U(1)$ Kac-Moody algebra. It is no doubt also recognized that in a somewhat similar way, the 4d $BF$ interaction (with $B$ a two form, $dB$ the dual $^*j$ of the eletromagnetic current, and F the electromagnetic field form) describes the scaling limit of a superconductor. We show in this paper that there are...

Source: http://arxiv.org/abs/hep-th/9205116v1

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Sep 19, 2013
09/13

by
A. P. Balachandran; S. M. Roy

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We derive differential equations for the modified Feynman propagator and for the density operator describing time-dependent measurements or histories continuous in time. We obtain an exact series solution and discuss its applications. Suppose the system is initially in a state with density operator $\rho(0)$ and the projection operator $E(t) = U(t) E U^\dagger(t)$ is measured continuously from $t = 0$ to $T$, where $E$ is a projector obeying $E\rho(0) E = \rho(0)$ and $U(t)$ a unitary operator...

Source: http://arxiv.org/abs/quant-ph/0102019v2

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Sep 22, 2013
09/13

by
A. P. Balachandran; A. M. Srivastava

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Theoretical developments during the past several years have shown that large scale properties of the Quantum Hall system can be successfully described by effective field theories which use the Chern-Simons interaction. In this article, we first recall certain salient features of the Quantum Hall Effect and their microscopic explanation. We then review one particular approach to their description based on the Chern-Simons Lagrangian and its variants.

Source: http://arxiv.org/abs/hep-th/9111006v1

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Sep 23, 2013
09/13

by
A. P. Balachandran; T. R. Govindarajan

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On Moyal space-time, one can implement twisted Poincar\'e symmetry with the resultant modification of symmetrization and anti-symmetrization postulates for bosons and fermions. We develop the thermofield approach of Umezawa and Takahashi on such a spacetime preserving the twisted Poincar\'e symmetry of the underlying quantum field theory(qft). Implications of this twisted Poincar\'e symmetry for qft's at finite temperature are pointed out.

Source: http://arxiv.org/abs/1006.1528v5

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Sep 23, 2013
09/13

by
A. P. Balachandran; S. Kurkcuoglu; S. Vaidya

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This is a preliminary version, comments and inputs are welcome. Contents: 1. Introduction. 2. Fuzzy Spaces. 3. Star Products. 4. Scalar Fields on the Fuzzy Sphere. 5. Instantons, Monopoles and Projective Modules. 6. Fuzzy Nonlinear Sigma Models. 7. Fuzzy Gauge Theories. 8. The Dirac Operator and Axial Anomaly. 9. Fuzzy Supersymmetry. 10.Fuzzy Spaces as Hopf Algebras.

Source: http://arxiv.org/abs/hep-th/0511114v2

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Sep 21, 2013
09/13

by
A. P. Balachandran; Anosh Joseph; Pramod Padmanabhan

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Quantum theories constructed on the noncommutative spacetime called the Groenewold-Moyal plane exhibit many interesting properties such as Lorentz and CPT noninvariance, causality violation and twisted statistics. We show that such violations lead to many striking features that may be tested experimentally. These theories predict Pauli forbidden transitions due to twisted statistics, anisotropies in the cosmic microwave background radiation due to correlations of observables in spacelike...

Source: http://arxiv.org/abs/0905.0876v1

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Sep 23, 2013
09/13

by
A. P. Balachandran; L. Chandar; Arshad Momen

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It is known that gauge fields defined on manifolds with spatial boundaries support states localized at the boundaries. In this paper, we demonstrate how coarse-graining over these states can lead to an entanglement entropy. In particular, we show that the entanglement entropy of the ground state for the quantum Hall effect on a disk exhibits an approximate ``area " law.

Source: http://arxiv.org/abs/hep-th/9512047v2

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Sep 18, 2013
09/13

by
Earnest Akofor; A. P. Balachandran; Anosh Joseph

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We give an introductory review of quantum physics on the noncommutative spacetime called the Groenewold-Moyal plane. Basic ideas like star products, twisted statistics, second quantized fields and discrete symmetries are discussed. We also outline some of the recent developments in these fields and mention where one can search for experimental signals.

Source: http://arxiv.org/abs/0803.4351v2

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Sep 20, 2013
09/13

by
A. P. Balachandran; A. Pinzul; B. Qureshi

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The N=1 SUSY on S^2 and its fuzzy finite-dimensional matrix version are known. The latter regulates quantum field theories, and seems suitable for numerical work and capable of higher dimensional generalizations. In this paper, we study their instanton sectors. They are SUSY generalizations of U(1) bundles on S^2 and their fuzzy versions, and can be characterized by $k\in\mathbb{Z}$, the SUSY Chern numbers. In the no-instanton sector (k=0), N=2 SUSY can be chirally realized, the 3 new N=2...

Source: http://arxiv.org/abs/hep-th/0506037v2

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Sep 18, 2013
09/13

by
A. P. Balachandran; L. Chandar; Arshad Momen

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We show in the context of Einstein gravity that the removal of a spatial region leads to the appearance of an infinite set of observables and their associated edge states localized at its boundary. Such a boundary occurs in certain approaches to the physics of black holes like the one based on the membrane paradigm. The edge states can contribute to black hole entropy in these models. A ``complementarity principle" is also shown to emerge whereby certain ``edge" observables are...

Source: http://arxiv.org/abs/gr-qc/9412019v2

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Sep 23, 2013
09/13

by
A. P. Balachandran; Amilcar R. de Queiroz

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In a previous paper, we discussed simple examples like particle on a circle and molecules to argue that mixed states can arise from anomalous symmetries. This idea was applied to the breakdown (anomaly) of color SU(3) in the presence of non-abelian monopoles. Such mixed states create entropy as well. In this article, we extend these ideas to the topological geons of Friedman and Sorkin in quantum gravity. The "large diffeos" or mapping class groups can become anomalous in their...

Source: http://arxiv.org/abs/1109.5290v1

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Jul 20, 2013
07/13

by
A. P. Balachandran; L. Chandar; E. Ercolessi

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Gauge theories on manifolds with spatial boundaries are studied. It is shown that observables localized at the boundaries (edge observables) can occur in such models irrespective of the dimensionality of spacetime. The intimate connection of these observables to charge fractionation, vertex operators and topological field theories is described. The edge observables, however, may or may not exist as well-defined operators in a fully quantized theory depending on the boundary conditions imposed...

Source: http://arxiv.org/abs/hep-th/9411164v2

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Sep 19, 2013
09/13

by
A. P. Balachandran; L. Chandar; B. Sathiapalan

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The edge states of a sample displaying the quantum Hall effect (QHE) can be described by a 1+1 dimensional (conformal) field theory of $d$ massless scalar fields taking values on a $d$-dimensional torus. It is known from the work of Naculich, Frohlich et al.\@ and others that the requirement of chirality of currents in this \underline{scalar} field theory implies the Schwinger anomaly in the presence of an electric field, the anomaly coefficient being related in a specific way to Hall...

Source: http://arxiv.org/abs/hep-th/9405141v4

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Sep 20, 2013
09/13

by
A. P. Balachandran; S. Kurkcuoglu; E. Rojas

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The fuzzy supersphere $S_F^{(2,2)}$ is a finite-dimensional matrix approximation to the supersphere $S^{(2,2)}$ incorporating supersymmetry exactly. Here the star-product of functions on $S_F^{(2,2)}$ is obtained by utilizing the OSp(2,1) coherent states. We check its graded commutative limit to $S^{(2,2)}$ and extend it to fuzzy versions of sections of bundles using the methods of [1]. A brief discussion of the geometric structure of our star-product completes our work.

Source: http://arxiv.org/abs/hep-th/0204170v2

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Sep 17, 2013
09/13

by
A. P. Balachandran; Anosh Joseph; Pramod Padmanabhan

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There are good reasons to suspect that spacetime at Planck scales is noncommutative. Typically this noncommutativity is controlled by fixed "vectors" or "tensors" with numerical entries. For the Moyal spacetime, it is the antisymmetric matrix $\theta_{\mu\nu}$. In approaches enforcing Poincar\'e invariance, these deform or twist the method of (anti-)symmetrization of identical particle state vectors. We argue that the earth's rotation and movements in the cosmos are...

Source: http://arxiv.org/abs/1003.2250v3

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Sep 18, 2013
09/13

by
A. P. Balachandran; S. Digal; T. Matsuura

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We show that topological superfluid strings/vortices with flux tubes exist in the color-flavor locked (CFL) phase of color superconductors. Using a Ginzburg-Landau free energy we find the configurations of these strings. These strings can form during the transition from the normal phase to the CFL phase at the core of very dense stars. We discuss an interesting scenario for a network of strings and its evolution at the core of dense stars.

Source: http://arxiv.org/abs/hep-ph/0509276v3

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Sep 19, 2013
09/13

by
A. P. Balachandran; L. Chandar; Arshad Momen

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It is well-known that gauge fields defined on manifolds with spatial boundaries support states localized at the boundary. In this talk, we show how similar states arise in canonical gravity abd discuss their physical relevance using their analogy to quantum Hall effect.

Source: http://arxiv.org/abs/gr-qc/9506006v2

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Sep 17, 2013
09/13

by
A. P. Balachandran; X. Martin; Denjoe O'Connor

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Previously matrix model actions for ``fuzzy'' fields have been proposed using non-commutative geometry. They retained ``topological'' properties extremely well, being capable of describing instantons, $\theta$--states, the chiral anomaly, and even chiral fermions with no ``doubling''. Here, we demonstrate that the standard scalar and spinor actions on a $d$--dimensional manifold are recovered from such actions in the limit of large matrices if their normalizations are correctly scaled as the...

Source: http://arxiv.org/abs/hep-th/0007030v1

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Sep 21, 2013
09/13

by
A. P. Balachandran; A. Pinzul; B. Qureshi

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Poincar\'e-invariant quantum field theories can be formulated on non-commutative planes if the coproduct on the Poincar\'e group is suitably deformed \cite{Dimitrijevic:2004rf, Chaichian:2004za}.(See also especially Oeckl \cite{Oeckl:1999jun},\cite{Oeckl:2000mar} and Grosse et al.\cite{Grosse:2001mar}) As shown in \cite{Balachandran:2005eb}, this important result of these authors implies modification of free field commutation and anti-commutation relations and striking phenomenological...

Source: http://arxiv.org/abs/hep-th/0508151v2