696 research outputs found
Drell-Yan Production of Z' in the Three-Site Higgsless Model at the LHC
In the Higgsless models, there are extra gauge bosons which keep the
perturbative unitarity of a longitudinally polarized gauge boson. The
three-site Higgsless model is a minimal Higgsless model and contains three
extra gauge bosons, and Z'. In this paper, we report the
discovery potential of the Z' gauge boson via Drell-Yan production with
Z'(mass=380, 500, 600 GeV) (,
) at the LHC (=14 TeV).Comment: 7 pages, 5 figures included. References revise
How Well Does AdS/QCD Describe QCD?
AdS/QCD is an extra-dimensional approach to modeling hadronic physics,
motivated by the AdS/CFT correspondence in string theory. AdS/QCD models are
often more accurate than would have been expected at energies below a few GeV.
We address the question of why these models are so successful, and respond to
some of the criticisms that have been waged against these models.Comment: To appear in proceedings of Crossing the Boundaries: Gauge Dynamics
at Strong Coupling (Shifmania), Minnesota, May 14-17, 2009. 12 pages, 2 eps
figure
Agriculture and the transition to the market
Agricultural sectors in Eastern and Central Europe are large so that changes in producer prices, farm employment, and land ownership affect substantial numbers of people. In the past, food in the region was politicized. For decades, governments of Eastern European countries and the USSR offered their citizens stable, subsidized food prices and a steadily improving diet in an effort to demonstrate the superiority of communism over capitalism. During the transition, the context has changed, but food remains politicized. Many consumers in the region are ill-prepared to pay the real costs of food, which are quite high. The task of reducing those costs will be difficult, involving restructuring of farms and fostering competition in processing and distribution. Management of the agricultural transition will affect the political sustainability of the process and influence agriculture's contribution to the growth of emerging market economies. Although the agricultural sector of Eastern and Central Europe is large, Soviet agriculture dwarfs it in its impact on the region and the world. A positive program to stop the decline in Soviet agriculture could contribute to economic growth and political stability. Failure to remedy the fundamental flaws in Soviet agriculture will speed the country's slide into poverty and ethnic turmoil - and undermine the efforts of Central and Eastern Europeans to succeed.Access to Markets,Environmental Economics&Policies,Economic Theory&Research,Agricultural Knowledge&Information Systems,Markets and Market Access
Composite MFV and Beyond
We revisit and extend realizations of Minimal Flavor Violation (MFV) in
theories with strongly coupled electro-weak symmetry breaking. MFV requires
that some chiralities of light SM quarks are strongly composite leading,
depending on the scenario, to bounds from compositeness searches, precision
electro-weak tests or even flavor physics. Within the framework of partial
compositeness we show how to extend the MFV paradigm allowing the treat the top
quark differently. This can be realized if for example the strong sector has an
U(2) symmetry. In this case the light generations can be mostly elementary and
all the bounds are easily satisfied.Comment: 16 pages. v2) estimates improved, conclusions unchange
Wave Function of the Radion in the dS and AdS Brane Worlds
We study the linearized metric perturbation corresponding to the radion for
the generalization of the five dimensional two brane setup of Randall and
Sundrum to the case when the curvature of each brane is locally constant but
non-zero. We find the wave fuction of the radion in a coordinate system where
each brane is sitting at a fixed value of the extra coordinate. We find that
the radion now has a mass, which is negative for the case of de Sitter
branes but positive for anti de Sitter branes. We also determine the couplings
of the radion to matter on the branes, and construct the four dimensional
effective theory for the radion valid at low energies. In particular we find
that in AdS space the wave function of the radion is always normalizable and
hence its effects, though small, remain finite at arbitrarily large brane
separations.Comment: Version which appears in Phys. Rev.
Five-dimensional Trinification Improved
We present improved models of trinification in five dimensions. Unified
symmetry is broken by a combination of orbifold projections and a boundary
Higgs sector. The latter can be decoupled from the theory, realizing a
Higgsless limit in which the scale of exotic massive gauge fields is set by the
compactification radius. Electroweak Higgs doublets are identified with the
fifth components of gauge fields and Yukawa interactions arise via Wilson
loops. The result is a simple low-energy effective theory that is consistent
with the constraints from proton decay and gauge unification.Comment: 13 pages LaTeX. v2: reference adde
Supersymmetric Gauge Theories with an Affine Quantum Moduli Space
All supersymmetric gauge theories based on simple groups which have an affine
quantum moduli space, i.e. one generated by gauge invariants with no relations,
W=0, and anomaly matching at the origin, are classified. It is shown that the
only theories with no gauge invariants (and moduli space equal to a single
point) are the two known examples, SU(5) with 5-bar + 10 and SO(10) with a
spinor. The index of the matter representation must be at least as big as the
index of the adjoint in theories which have a non-trivial relation among the
gauge invariants.Comment: Incorrect proof that theories with constraints must have mu >=
mu(adj) replaced by a correct one (6 pages, uses revtex, amssymb, array
On the consistency of the N=1 SYM spectra from wrapped five-branes
We discuss the existence of glueball states for N=1 SYM within the
Maldacena-Nunez model. We find that for this model the existence of an area law
in the Wilson loop operator does not imply the existence of a discrete glueball
spectrum. We suggest that implementing the model with an upper hard cut-off can
amend the lack of spectrum. As a result the model can be only interpreted in
the infra-red region. A direct comparison with the lattice data allows us to
fix the scale up to where the model is sensible to describe low-energy
observables. Nevertheless, taking for granted the lattice results, the
resulting spectrum does not follow the general trends found in other
supergravity backgrounds. We further discuss the decoupling of the non-singlet
Kaluza-Klein states by analysing the associated supergravity equation of
motion. The inclusion of non-commutative effects is also analysed and we find
that leads to an enhancement on the value of the masses.Comment: 30 pages, late
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