arXiv subjects

Adam Falkowski

Publications and source records attributed to Adam Falkowski.

102 records · Page 6Linked to original sources

arXiv2005

On the one-loop Kahler potential in five-dimensional brane-world supergravity

We present an on-shell formulation of 5d gauged supergravity coupled to chiral matter multiplets localized at the orbifold fixed points. The brane action is constructed via the Noether method. In such set-up we compute one-loop corrections to the Kahler potential of the effective 4d supergravity and compare the result with previous computations based on the off-shell formalism. The results agree at lowest order in brane sources, however at higher order there are differences. We explain this discrepancy by an ambiguity in resolving singularities associated with the presence of infinitely thin branes.

hep-th↗

arXiv2004

Electroweak symmetry breaking in supersymmetric models with heavy scalar superpartners

We propose a novel mechanism of electroweak symmetry breaking in supersymmetric models, as the one recently discussed by Birkedal, Chacko and Gaillard, in which the Standard Model Higgs doublet is a pseudo-Goldstone boson of some global symmetry. The Higgs mass parameter is generated at one loop level by two different, moderately fine-tuned sources of the global symmetry breaking. The mechanism works for scalar superpartner masses of order 10 TeV, but gauginos can be light. The scale at which supersymmetry breaking is mediated to the visible sector has to be low, of order 100 TeV. Fine-tuning in the scalar potential is at least two orders of magnitude smaller than in the MSSM with similar soft scalar masses. The physical Higgs boson mass is (for $\tanβ\gg1$) in the range 120-135 GeV.

hep-ph↗

arXiv2003

Deconstructing 5D supersymmetric U(1) gauge theories on orbifolds

We investigate deconstruction of five dimensional supersymmetric abelian gauge theories compactified on $S_1/Z_2$, with various sets of bulk and matter multiplets. The problem of anomalies, chirality and stability in the deconstructed theories is discussed. We find that for most of the 5d brane/bulk matter assignments there exists the deconstructed version. There are, however, some exceptions.

hep-th↗

arXiv2003

Cosmological constant and kinetic supersymmetry breakdown on a moving brane

We consider cosmological solutions in 5d locally supersymmetric theories including boundary actions, with either opposite tension branes for identical brane chiralities or equal tension branes for flipped brane chiralities. We analyse the occurrence of supersymmetry breakdown in both situations. We find that supersymmetry as seen by a brane observer is broken due to the motion of the brane in the bulk. When the brane energy-momentum tensor is dominated by the brane tension, the 4d vacuum energy cosmological constant on the observable brane is positive and proportional to the inverse square of the brane local time. We find that the mass splitting within supersymmetric multiplets living on the brane is of the order of the inverse of the brane local time, examplifying the tight relation between the vacuum energy scale and the supersymmetry breaking scale.

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arXiv2003

Deconstructed U(1) and Supersymmetry Breaking

We discuss supersymmetry breaking induced by simultaneous presence of a Wilson-line type superpotential and boundary-localized Fayet-Iliopoulos terms in a four dimensional theory based on deconstruction of five-dimensional abelian gauge theories on orbifolds. Large hierarchy between the scale of supersymmetry breaking and the fundamental scale can be generated dynamically. The model has several potentially interesting phenomenological applications. We also discuss the conditions that are necessary for interpreting our $U(1)^N$ model as an ultra-violet completion of some 5d theory. In particular, the corresponding 5d theory contains Chern-Simons couplings.

hep-th↗

arXiv2002

Running of Gauge Couplings in AdS5 via Deconstruction

Running of gauge couplings on a slice of AdS5 is examined using the deconstruction set-up. Logarithmic running instead of (linear) power law is justified when the cutoff is lower than the curvature scale. Most of interesting features in warped gauge theory including the localization of Kaluza-Klein modes, the widening of higher Kaluza-Klein spectrum spacing are well captured within the framework of the deconstruction.

hep-ph↗

arXiv2002

Custodial supersymmetry in non-supersymmetric quiver theories

We consider non-supersymmetric quiver theories obtained by orbifolding the N=4 supersymmetric U(K) gauge theory by a discrete Z_Γgroup embedded in the SU(4) R-symmetry group. We explicitly find that in such theories there are no one-loop quadratic divergences in the effective potential. Moreover, when the gauge group U(n)^Γof the quiver theory is spontaneously broken down to the diagonal U(n), we identify a custodial supersymmetry which is responsible for the fermion-boson degeneracy of the mass spectrum.

hep-th↗

arXiv2001

Non-BPS Branes of Supersymmetric Brane Worlds

We consider five-dimensional brane worlds with N=2 gauged supergravity in the bulk coupled supersymmetrically to two boundary branes at the fixed points of a Z_2 symmetry. We analyse two mechanisms that break supersymmetry either by choosing flipped fermionic boundary conditions on the boundary branes or by modifying the gravitino variation to include both Z_2-odd and Z_2-even operators. In all cases we find the corresponding background. Including an even part in the gravitino variation leads to tilted branes. Choosing the flipped boundary conditions leads to AdS_4 branes and stabilized radion in the detuned case, when the expectation value of the even variation is nonzero. Another solution has the interpretation of moving AdS_4 branes separated by a horizon. The solution with moving branes separated by a horizon can be extended to the tuned case. In the presence of a horizon, temperature mediation communicates supersymmetry breakdown to the branes.

hep-th↗

arXiv2001

Unification in models with replicated gauge groups

We examine unification of gauge couplings in four dimensional renormalizable gauge theories inspired by the latticized (deconstructed) SM or MSSM in five dimensions. The models are based on replicated gauge groups, spontaneously broken to the diagonal subgroup. The analysis is performed at one-loop level, with the contribution from the heavy vector bosons included, and compared with the analogous results in the SM or MSSM. Unification at or above the diagonal breaking scale is discussed. We find that in the considered class of extensions of the SM(MSSM) unification is possible for a wide range of unification scales and with the similar accuracy as in the SM(MSSM). Unification above the diagonal breaking scale is particularly attractive: it is a consequence of the SM(MSSM) unification, but with the unification scale depending on the number of replications of the gauge group.

hep-ph↗

arXiv2001

Four-Dimensional Supergravities from Five-Dimensional Brane Worlds

We give the explicit form of the four dimensional effective supergravity action, which describes low energy physics of the Randall-Sundrum model with moduli fields in the bulk and charged chiral matter living on the branes. The relation between 5d and 4d physics is explicit: the low energy action is derived from the compactification of a locally supersymmetric model in five dimension. The presence of odd $Z_2$ parity scalars in the bulk gives rise to effective potential for the radion in four dimensions. We describe the mechanism of supersymmetry breaking mediation, which relies on non-trivial configuration of these $Z_2$-odd bulk fields. Broken supersymmetry leads to stabilization of the interbrane distance.

hep-th↗

arXiv2000

Five-Dimensional Gauged Supergravities with Universal Hypermultiplet and Warped Brane Worlds

We present five dimensional gauged supergravity with universal hypermultiplet on M_4 \times S^1 / Z_2 coupled supersymmetrically to three-branes located at the fixed points. The construction is extended to the smooth picture with auxiliary singlet and four-form fields. The model admits the Randall-Sundrum solution as a BPS vacuum with vanishing energy. We give the form of all KK-tower modes for fields present in the model.

hep-th↗

arXiv2000

Supersymmetrizing Branes with Bulk in Five-Dimensional Supergravity

We supersymmetrize a class of moduli dependent potentials living on branes with the help of additional bulk terms in 5d N=2 supergravity. The space of Poincare invariant vacuum solutions includes the Randall-Sundrum solution and the $M$-theoretical solution. After adding gauge sectors to the branes we discuss breakdown of low energy supersymmetry in this setup and hierarchy of physical scales. In the limit of large warp factors we find decoupling between effects stemming from different branes in the compactified theory.

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