1,182 research outputs found
Deconstruction and Gauge Theories in AdS_5
On a slice of AdS_5, despite having a dimensionful coupling, gauge theories
can exhibit logarithmic dependence on scale. In this paper, we utilize
deconstruction to analyze the scaling behavior of the theory, both above and
below the AdS curvature scale, and shed light on position-dependent
regularizations of the theory. We comment on applications to geometries other
than AdS.Comment: 15 pages, 1 figur
Gauge Theories in and Fine-Lattice Deconstruction
The logarithmic energy dependence of gauge couplings in AdS_5 emerges almost
automatically when the theory is deconstructed on a coarse lattice. Here we
study the theory away from the coarse-lattice limit. While we cannot
analytically calculate individual KK masses for a fine lattice, we can
calculate the product of all non-zero masses. This allows us to write down the
gauge coupling at low energies for any lattice-spacing and curvature. As
expected, the leading log behaviour is corrected by power-law contributions,
suppressed by the curvature. We then turn to intermediate energies, and discuss
the gauge coupling and the gauge boson profile in perturbation theory around
the coarse-lattice limit.Comment: 17 pages, 1 figure, typos in listing version of abstract correcte
Supersymmetry Breaking and Moduli Stabilization with Anomalous U(1) Gauge Symmetry
We examine the effects of anomalous U(1)_A gauge symmetry on soft
supersymmetry breaking terms while incorporating the stabilization of the
modulus-axion multiplet responsible for the Green-Schwarz (GS) anomaly
cancellation mechanism. In case of the KKLT stabilization of the GS modulus,
soft terms are determined by the GS modulus mediation, the anomaly mediation
and the U(1)_A mediation which are generically comparable to each other,
thereby yielding the mirage mediation pattern of superparticle masses at low
energy scale. Independently of the mechanism of moduli stabilization and
supersymmetry breaking, the U(1)_A D-term potential can not be an uplifting
potential for de Sitter vacuum when the gravitino mass is smaller than the
Planck scale by many orders of magnitude. We also discuss some features of the
supersymmetry breaking by red-shifted anti-brane which is a key element of the
KKLT moduli stabilization.Comment: 32 pages; references are adde
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.Comment: 20 pages, 3 figures, revtex, refereces added and typos corrected; the
version published in JHE
Weak boson scattering in Gauge-Higgs Unification
The scattering amplitude for the longitudinal weak bosons is investigated in
the SU(3) gauge-Higgs unification as a function of the scattering energy, the
Wilson line phase \theta_H and the warp factor. The \theta_H-dependence of the
amplitude is quite different in the flat and the warped spacetimes. Generically
the amplitude is enhanced for \theta_H=O(1) in the warped case while it is
almost independent of \theta_H in the flat case. This indicates the tree-level
unitarity is violated in the warped case at a lower scale than that in the flat
case.Comment: 22 pages, 8 figures, published version in JHE
Tools for Deconstructing Gauge Theories in AdS5
We employ analytical methods to study deconstruction of 5D gauge theories in
the AdS5 background. We demonstrate that using the so-called q-Bessel functions
allows a quantitative analysis of the deconstructed setup. Our study clarifies
the relation of deconstruction with 5D warped theories.Comment: 30 pages; v2: several refinements, references adde
One loop gauge couplings in AdS5
We calculate the full 1-loop corrections to the low energy coupling of bulk
gauge boson in a slice of AdS5 which are induced by generic 5-dimensional
scalar, Dirac fermion, and vector fields with arbitrary Z_2 times Z_2' orbifold
boundary conditions. In supersymmetric limit, our results correctly reproduce
the results obtained by an independent method based on 4-dimensional effective
supergravity. This provides a nontrivial check of our results and assures the
regularization scheme-independence of the results.Comment: RevTeX, 22 pages, 2 figures, some typos corrected and notations
change
ROSETTA: an operator basis translator for standard model effective field theory
We introduce Rosetta, a program allowing for the translation between different bases of effective field theory operators.We present the main functions of the program and provide an example of usage. One of the Lagrangians which Rosetta can translate into has been implemented into FeynRules, which allows Rosetta to be interfaced into various high-energy physics programs such as Monte Carlo event generators. In addition to popular bases choices, such as the Warsaw and Strongly Interacting Light Higgs bases already implemented in the program, we also detail how to add new operator bases into the Rosetta package. In this way, phenomenological studies using an effective field theory framework can be straightforwardly performe
Systematic Implementation of Implicit Regularization for Multi-Loop Feynman Diagrams
Implicit Regularization (IReg) is a candidate to become an invariant
framework in momentum space to perform Feynman diagram calculations to
arbitrary loop order. In this work we present a systematic implementation of
our method that automatically displays the terms to be subtracted by
Bogoliubov's recursion formula. Therefore, we achieve a twofold objective: we
show that the IReg program respects unitarity, locality and Lorentz invariance
and we show that our method is consistent since we are able to display the
divergent content of a multi-loop amplitude in a well defined set of basic
divergent integrals in one loop momentum only which is the essence of IReg.
Moreover, we conjecture that momentum routing invariance in the loops, which
has been shown to be connected with gauge symmetry, is a fundamental symmetry
of any Feynman diagram in a renormalizable quantum field theory
Efficient, Near-Infrared Light-Induced Photoclick Reaction Enabled by Upconversion Nanoparticles
Photoclick reactions combine the selectivity of classical click chemistry with the high precision and spatiotemporal control afforded by light, finding diverse utility in surface customization, polymer conjugation, photocross-linking, protein labeling, and bioimaging. Nonetheless, UV light, pivotal in prevailing photoclick reactions, poses issues, especially in biological contexts, due to its limited tissue penetration and cell-toxic nature. Herein, a reliable and versatile strategy of activating the photoclick reactions of 9,10-phenanthrenequinones (PQs) with electron-rich alkenes (ERAs) with near infrared (NIR) light transduced by spectrally and structurally customized upconversion nanoparticles (UCNPs) is introduced. Under NIR irradiation, the UCNPs become UV/blue nanoemitters uniformly distributed in the reaction system. Enabled by the customized UCNPs, 800 or 980 nm light effectively activates the photocycloaddition reactions via radiative energy transfer in both general and triplet–triplet energy transfer (TTET)-mediated PQ-ERA systems. In particular, the novel sandwich structure UCNPs achieve the click reaction with up to 76% production yield in 10 min under NIR light irradiation. Meanwhile, the tricky side effect of photoclick product absorption-induced quenching is successfully circumvented from the fine-tuning of the upconversion spectrum. Moreover, through-tissue irradiation experiments, the authors show that the UCNP-PQ-ERA reaction unlocks the full potential of photoclick reactions for in vivo applications.</p
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