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2021, Cornell University - arXiv
In the old spirit of Kaluza-Klein, we consider a spacetime of the form P = M 4 × K, where K is the Lie group SU(3) equipped with a left-invariant metric that is not fully rightinvariant. This metric has a U(1) × SU(3) isometry group, corresponding to the massless gauge bosons, and depends on a parameter φ with values in a subspace of su(3) isomorphic to C 2. It is shown that the classical Einstein-Hilbert Lagrangian density R P − 2Λ on the higher-dimensional manifold P , after integration over K, encodes not only the Yang-Mills terms of the Standard Model over M 4 , as in the usual Kaluza-Klein calculation, but also a kinetic term |d A φ| 2 identical to the covariant derivative of the Higgs field. For Λ in an appropriate range, it also encodes a potential V (|φ| 2) having absolute minima with |φ 0 | 2 = 0, thereby inducing mass terms for the remaining gauge bosons. The classical masses of the resulting Higgs-like and gauge bosons are explicitly calculated as functions of the vacuum value |φ 0 | 2 in the simplest version of the model. In more general versions, the classical values of the strong and electroweak gauge coupling constants are given as functions of the parameters of the left-invariant metric on K.
Physical Review D, 2003
We consider the possibility that the standard model Higgs fields may originate from extra components of higher dimensional gauge fields. Theories of this type considered before have had problems accommodating the standard model fermion content and Yukawa couplings different from the gauge coupling. Considering orbifolds based on abelian discrete groups we are lead to a 6 dimensional G 2 gauge theory compactified on T 2 /Z 4 . This theory can naturally produce the SM Higgs fields with the right quantum numbers while predicting the value of the weak mixing angle sin 2 θ W = 0.25 at the tree-level, close to the experimentally observed one. The quartic scalar coupling for the Higgs is generated by the higher dimensional gauge interaction and predicts the existence of a light Higgs. We point out that one can write a quadratically divergent counter term for Higgs mass localized to the orbifold fixed point. However, we calculate these operators and show that higher dimensional gauge interactions do not generate them at least at one loop. Fermions are introduced at orbifold fixed points, making it easy to accommodate the standard model fermion content. Yukawa interactions are generated by Wilson lines. They may be generated by the exchange of massive bulk fermions, and the fermion mass hierarchy can be obtained. Around a TeV, the first KK modes would appear as well as additional fermion modes localized at the fixed point needed to cancel the quadratic divergences from the Yukawa interactions. The cutoff scale of the theory could be a few times 10 TeV. * The result concerns pure gauge theories in the bulk. Once matter is introduced, in a supersymmetric context for instance, some gauge invariant quadratic divergences can be generated at orbifold fixed points . * There is another possibility that the rank of the unbroken gauge group is higher than two, while the unwanted part of the group breaks itself because of the anomaly . In this case, one needs to rely on the Green-Schwarz mechanism for anomaly cancellation in the full theory.
We incorporate the parameters of the gauge group G into the gauge theory of interactions through a non-linear partial-trace σ-model Lagrangian on G/H . The minimal coupling of the new (Goldstone-like) scalar bosons provides mass terms to those intermediate vector bosons associated with the quotient G/H , without spoiling gauge invariance, remaining the H -vector potentials massless. The main virtue of a partial trace on G/H , rather than on the entire G, is that we can find an infinite-dimensional symmetry, with non-trivial Noether invariants, which ensures quantum integrability in a non-canonical quantization scheme. The present formalism is explicitly applied to the case G = S U (2) × U (1), as a Higgs-less alternative to the Standard Model of electroweak interactions, although it can also be used in low-energy phenomenological models for strong interactions.
In this work, the mass of the Higgs boson is calculated, its comparison with the W and Z boson masses established, and the μ 2 and λ parameters of the Higgs potential are fixed. This is done by looking at the ground states of three and four dimensional harmonic oscillators, and getting inferences from the strong black hole as well the MIT bag model formalisms. An "exact" relationship linking the masses of these bosons, advanced by DNA Forrester, is also taken in account. The Standard Model (SM) of Particle Physics is a theory describing the visible part of the stuff of the universe [1]. The SM Lagrangian contains fermionic fields, which excitations are quarks and leptons, and bosonic fields the mediators of the interactions and having as excitations the photon, W and Z bosons, and gluons. However, in order to give leptons and quarks (current) masses, and also to give masses to the W and Z bosons of the weak interactions, these fermionic and bosonic fields must interact (couple) with another spin-zero field:-the Higgs field. The quantum excitation of the Higgs field produces a Higgs boson (please see: "Higgs boson" in Wikipedia [2], and references cited therein). The Higgs mechanism, indeed also proposed by Robert Brout and François Englert; Gerald Guralnik, C. Richard Hagen, and Tom Kibble; besides Peter Higgs himself, gives particles their masses (current masses in the quark case).[3,4,5].The Higgs mechanism works through the process called spontaneous symmetry breaking [6]. As was pointed out by Wilczek [7], the mass of the Higgs particle itself is not explained in the theory, but appears as a free parameter. Here we are going to focus on the Higgs and Electroweak sectors of the SM.
1998
A new method of deriving the Higgs Lagrangian from vector-like gauge theories is explored. After performing a supersymmetric extension of gauge theories we identify the auxiliary field associated with the "meson" superfield, in the low energy effective theory, as the composite Higgs field. The auxiliary field, at tree level, has a "negative squared mass". By computing the one-loop effective action in the low energy effective theory, we show that a kinetic term for the auxiliary field emerges when an explicit non-perturbative mechanism for supersymmetry breaking is introduced. We find that, due to the naive choice of the Kähler potential, the Higgs potential remains unbounded from the below. A possible scenario for solving this problem is presented. It is also shown that once chiral symmetry is spontaneously broken via a non-zero vacuum expectation value of the Higgs field, the low energy composite fermion field acquires a mass and decouples, while in the supersymmetric limit it was kept massless by the 't Hooft anomaly matching conditions. 11.30.Pb, 11.30.Qc
Classical and Quantum Gravity, 2009
involves the spacetime metric g_{mu nu} as well as the induced metric \bar{g}_{mu nu} proportional to \eta_{a b} \partial_{mu} \phi^a \partial_{nu} \phi^b where \phi^{a} (a=0,...,3), as we call it, break all four diffeomorphisms spontaneously via the vacuum expectation values < \phi^a > proportional to x^a. In this framework, we construct and analyze the most general action density in terms of various invariants involving the curvature tensors, connexion coefficients, and the contractions and the determinants of the two metric fields. We show that this action admits a consistent expansion about the flat background such that the resulting Lagrangian possesses several novel features not found in the linearized Einstein-Hilbert Lagrangian with Fierz-Pauli mass term (LELHL-FP): (i) its kinetic part generalizes that of LELHL-FP by weighing the corresponding structures with certain coefficients generated by invariants, (ii) the entire Lagrangian is ghost-- and tachyon--free for mass terms not necessarily in the Fierz-Pauli form, and, (iii) a consistent mass term is generated with no apparent need to higher derivative couplings.
Modern Physics Letters A, 2015
In this paper, motivated by the recent discovery of a Higgs-like boson at the Large Hadron Collider (LHC) with a mass mH≃125 GeV , we review different models where the hierarchy problem is solved by means of a warped extra dimension. In the Randall–Sundrum (RS) model electroweak observables provide very strong bounds on the mass of KK modes which motivates extensions to overcome this problem. Two extensions are briefly discussed. One particular extension is based on the deformation of the metric such that it strongly departs from the AdS5 structure in the IR region while it goes asymptotically to AdS5 in the UV brane. This model has the IR brane close to a naked metric singularity (which is outside the physical interval) characteristic of soft-walls constructions. The proximity of the singularity provides a strong wave function renormalization for the Higgs field which suppresses the T and S parameters. The second class of considered extensions are based on the introduction of an ex...
Journal of High Energy Physics, 2009
We use the novel Higgs mechanism of arXiv:0803.3218 to determine the leading higher-derivative corrections to the Euclidean N = 8 Bagger-Lambert-Gustavsson field theory. The result matches that previously found for Lorentzian 3-algebras, pointing to a universal answer for all maximally supersymmetric 3-algebra theories. We also comment on the extension to the lower-supersymmetric case of ABJM theory.
arXiv (Cornell University), 1996
By using the Ward-Takahashi identities in the Landau gauge, we derive exact relations between particle masses and the vacuum expectation value of the Higgs field in the Abelian gauge field theory with a Higgs meson.
Physical Review D, 2004
Recently, "Higgsless" models of electroweak symmetry breaking have been proposed. Based on compactified five-dimensional gauge theories, these models achieve unitarity of electroweak boson self-interactions through the exchange of a tower of massive vector bosons rather than the exchange of a scalar Higgs boson. In this paper, using deconstruction, we analyze the form of the corrections to the electroweak interactions in a large class of these models, allowing for arbitrary 5-D geometry, position-dependent gauge coupling, and brane kinetic energy terms. We show that many models considered in the literature, including those most likely to be phenomenologically viable, are in this class. By analyzing the asymptotic behavior of the correlation function of gauge currents at high momentum, we extract the exact form of the relevant correlation functions at tree-level and compute the corrections to precision electroweak observables in terms of the spectrum of heavy vector bosons. We determine when nonoblique corrections due to the interactions of fermions with the heavy vector bosons become important, and specify the form such interactions can take. In particular we find that in this class of models, so long as the theory remains unitary, S −4 cos 2 θ W T > O(1), where S and T are the usual oblique parameters. We concur with the result of Cacciapaglia et.al. that small or negative S is possible -though only at the expense of substantial negative T at tree-level. Although we stress our results as they apply to continuum 5-D models, they apply also to models of extended electroweak gauge symmetries motivated by models of hidden local symmetry.
Journal of Physics A, 2010
We consider a diffeomorphism invariant theory of a gauge field valued in a Lie algebra that breaks spontaneously to the direct sum of the spacetime Lorentz algebra, a Yang-Mills algebra, and their complement. Beginning with a fully gauge invariant action-an extension of the Plebanski action for general relativity-we recover the action for gravity, Yang-Mills, and Higgs fields. The low-energy coupling constants, obtained after symmetry breaking, are all functions of the single parameter present in the initial action and the vacuum expectation value of the Higgs.
1998
We explore a novel way of deriving the effective Higgs Lagrangian from strongly interacting vectorlike gauge theories. We consider the N = 1 supersymmetric extension of gauge theories and interpret the auxiliary field associated with the low energy effective "meson" superfield as the Higgs field. By introducing an explicit supersymmetry breaking term and computing the one-loop effective action at the effective theory level we show that the kinetic term for the Higgs field is generated, while the negative mass squared term is already present at the tree level. We further propose a scenario by which the complete Higgs potential can be generated and the fermion in the low energy effective theory acquires a mass. Spontaneous symmetry breaking as described by the Higgs Lagrangian (linear σ-model) has always been the least appealing ingredient of the standard model. It is a wide spread hope that some new and more fundamental gauge dynamics could explain it. However it is in general very hard to show how the Higgs Lagrangian actually appears as a low energy effective theory. This problem would indeed require to solve the full strong coupling dynamics for gauge theories. In this letter we explore a new method which shows how the effective Higgs Lagrangian can emerge from gauge theories.
Modern Physics Letters A, 2016
We examine the possibility of observing the Kaluza–Klein (KK) gluons in gauge-Higgs unification models at the LHC with the energy [Formula: see text][Formula: see text]=[Formula: see text]14 TeV. We consider a benchmark model with the gauge symmetry SU(3)[Formula: see text]SU(3)W in five-dimensional spacetime, where SU(3)C is the gauge symmetry of the strong interaction and SU(3)W is that for the electroweak interaction and a Higgs doublet field. It is natural in general to introduce SU(3)C gauge symmetry in five-dimensional spacetime as well as SU(3)W gauge symmetry in gauge-Higgs unification (GHU) models. Since the fifth dimension is compactified to [Formula: see text] orbifold, there are KK modes of gluons in low-energy effective theory in four-dimensional spacetime. We investigate the resonance contribution of the first KK gluon to dijet invariant mass distribution at the LHC, and provide signal-to-noise ratios in various cases of KK gluon masses and kinematical cuts. Although t...
Physical Review D, 2011
New Massive Gravity provides a non-linear extension of the Fierz-Pauli mass for gravitons in 2+1 dimensions. Here we construct a Weyl invariant version of this theory. When the Weyl symmetry is broken, the graviton gets a mass in analogy with the Higgs mechanism. In (anti)de Sitter backgrounds, the symmetry can be broken spontaneously, but in flat backgrounds radiative corrections, at the two loop level, break the Weyl symmetry à la Coleman-Weinberg mechanism. We also construct the Weyl invariant extensions of some other higher derivative models, such as the Gauss-Bonnet theory ( which yields an interesting result especially in three dimensions ) and the Born-Infeld type gravities.
Physical Review D, 2001
We study a non-commutative generalization of the standard electroweak model proposed by Balakrishna, Gürsey and Wali [Phys. Lett. B254(1991)430] that is formulated in terms of the derivations Der2(M3) of a three-dimensional representation of the su(2) Lie algebra of weak isospin. The linearized Higgs field equations and the scalar boson mass eigenvalues are explicitly given. A light Higgs boson with mass around 130 GeV together with four very heavy scalar bosons are predicted.
Journal of Physics: Conference Series, 2011
The vector boson masses are generated by transformation of the free (without any potential term) Lagrangian of the Electroweak Model from Cartesian coordinates to a coordinates on the sphere S3, which is defined by the gauge invariant quadratic form φ † φ = ρ 2 in the matter field space Φ2. This transformation corresponds to transition from linear representation of the gauge group in the space Φ2 to its nonlinear representation in the space of functions on S3. Such modified Electroweak Model keep all experimentally verified fields of the standard Electroweak Model and does not include massive scalar field (Higgs boson), if the sphere radius does not depend on the space-time coordinates ρ = R = const. The concept of generation masses for vector bosons in Electroweak Model by transformation to radial coordinates is further developed in context of nonlinearly realized gauge groups, as well as in context of nonlinear sigma models. The limiting case of the modified Electroweak Model which corresponds to the contracted gauge group is discussed.
Physical Review D, 2006
Interactions among the standard model gauge bosons and scalar fields in the framework of SU(3)C ⊗ SU(3)L ⊗ U(1)X gauge model with minimal (economical) Higgs content are presented. From these couplings, all scalar fields including the neutral scalar h and the Goldstone bosons can be identified and their couplings with the usual gauge bosons such as the photon, the charged W ± and the neutral Z, without any additional condition, are recovered. In the effective approximation, full content of scalar sector can be recognized. The CP-odd part of Goldstone associated with the neutral non-Hermitian bilepton gauge boson G X 0 is decouple, while its CP-even counterpart has the mixing by the same way in the gauge boson sector. Masses of the new neutral Higgs boson H 0 1 and the neutral non-Hermitian bilepton X 0 are dependent on a coefficient of Higgs self-coupling (λ1). Similarly, masses of the singly-charged Higgs boson H ± 2 and of the charged bilepton Y ± are proportional through a coefficient of Higgs self-interaction (λ4). The hadronic cross section for production of this Higgs boson at the LHC in the effective vector boson approximation is calculated. Numerical evaluation shows that the cross section can exceed 260 f b.
The standard approach to Higgs mechanism is based on the existence of unitary gauge but, unfortunately, it does not come from a coordinate change in the configuration space of the initial model and actually defines a new dynamical system. So, it is a questionable approach to the problem but it is shown here that the final result could still make sense as a Marsden-Weinstein reduced system. (This reduction can be seen as completely analogous to the procedure of obtaining the "centrifugal" potential in the classical Kepler problem.) It is shown that in the standard linearization approximation of the Coulomb gauged Higgs model geometrical constraint theory offers an explanation of the Higgs mechanism because solving of the Gauss law constraint leads to different physical submanifolds which are not preserved by the action of the (broken) global U(1) group.
The European Physical Journal C, 2018
For the Yang-Mills theory coupled to a single scalar field in the fundamental representation of the gauge group, we present a gauge-independent description of the Brout-Englert-Higgs mechanism by which massless gauge bosons acquire their mass. The new description should be compared with the conventional gauge-dependent description relying on the spontaneous gauge symmetry breaking due to a choice of the non-vanishing vacuum expectation value of the scalar field. In this paper we focus our consideration on the fundamental scalar field which extends the previous work done for the Yang-Mills theory with an adjoint scalar field. Moreover, we show that the Yang-Mills theory with a gauge-invariant mass term is obtained from the corresponding gauge-scalar model when the radial degree of freedom (length) of the scalar field is fixed. The result obtained in this paper is regarded as a continuum realization of the Fradkin-Shenker continuity and Osterwalder-Seiler theorem for the complementarity between Higgs regime and Confinement regime which was given in the gauge-invariant framework of the lattice gauge theory. Moreover, we discuss how confinement is investigated through the gaugeindependent Brout-Englert-Higgs mechanism by starting with the complementary gauge-scalar model.
Nuclear Physics B, 2002
The electroweak Higgs doublets are identified as components of a vector multiplet in a higher dimensional supersymmetric field theory. We construct a minimal model in 6D where the electroweak SU (2) ⊗ U (1) gauge group is extended to SU (3), and unified 6D models with the unified SU (5) gauge symmetry extended to SU (6). In these realistic theories the extended gauge group is broken by orbifold boundary conditions, leaving Higgs doublet zero modes which have Yukawa couplings to quarks and leptons on the orbifold fixed points. In one SU (6) model the weak mixing angle receives power law corrections, while in another the fixed point structure forbids such corrections. A 5D model is also constructed in which the Higgs doublet contains the fifth component of the gauge field. In this case Yukawa couplings are introduced as non-local operators involving the Wilson line of this gauge field.
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