58 research outputs found
Extension of the Poincar\'e Group and Non-Abelian Tensor Gauge Fields
In the recently proposed generalization of the Yang-Mills theory the group of
gauge transformation gets essentially enlarged. This enlargement involves an
elegant mixture of the internal and space-time symmetries. The resulting group
is an extension of the Poincar\'e group with infinitely many generators which
carry internal and space-time indices. This is similar to the super-symmetric
extension of the Poincar\'e group, where instead of an anti-commuting spinor
variable one should introduce a new vector variable. The construction of
irreducible representations of the extended Poincar\'e algebra identifies a
vector variable with the derivative of the Pauli-Lubanski vector over its
length. As a result of this identification the generators of the gauge group
have nonzero components only in the plane transversal to the momentum and are
projecting out non-Abelian tensor gauge fields into the transversal plane,
keeping only their positively definite space-like components.Comment: 21 page
Possible quantum kinematics. II. Non-minimal case
The quantum analogs of the N-dimensional Cayley-Klein spaces with different
combinations of quantum and Cayley-Klein structures are described for
non-minimal multipliers, which include the first and the second powers of
contraction parameters in the transformation of deformation parameter. The
noncommutative analogs of (N-1)-dimensional constant curvature spaces are
introduced. Part of these spaces for N=5 are interpreted as the noncommutative
analogs of (1+3) space-time models. As a result the wide variety of the quantum
deformations of realistic kinematics are suggested.Comment: 13 pages, no figure
From Symmetry to Supersymmetry
This text is the draft of Julius Wess' contribution to the Proceedings of
SUSY07 (KIT Karlsruhe) and to "Supersymmetry at the dawn of the LHC" in Eur.
Phys. J. C59/2. The manuscript, which Wess could not finish before his death,
has been edited for the publication.Comment: Feb.2009 - Contribution edited for the Proceedings SUSY07 (KIT
Karlsruhe) and "Supersymmetry at the dawn of the LHC" in Eur. Phys. J. C59/
Spinning particle in an external linearized gravitational wave field
We study the interaction of a scalar and a spinning particle with a coherent
linearized gravitational wave field treated as a classical spin two external
field. The spin degrees of freedom of the spinning particle are described by
skew-commuting variables. We derive the explicit expressions for the
eigenfunctions and the Green's functions of the theory. The discussion is exact
within the approximation of neglecting radiative corrections and we prove that
the result is completely determined by the semiclassical contribution.Comment: 11 page
On contractions of classical basic superalgebras
We define a class of orthosymplectic and unitary
superalgebras which may be obtained from and
by contractions and analytic continuations in a similar way as the
special linear, orthogonal and the symplectic Cayley-Klein algebras are
obtained from the corresponding classical ones. Casimir operators of
Cayley-Klein superalgebras are obtained from the corresponding operators of the
basic superalgebras. Contractions of and are regarded as
an examples.Comment: 15 pages, Late
Relation between confinement and higher symmetry restrictions for color particle motion
Quantum operators of coordinates and momentum components of a particle in the
Minkowski spacetime can belong to the generalized Snyder-Yang algebra and
produce a quantum phase space with three new constants in the general case.
With account for the O(2,6) invariance in the quantum phase space of a color
particle the equation of motion is obtained, which contains a oscillator rising
potential. The presence of the oscillator potential can simulate a confinement
of a color particle. A parameter of the oscillator potential is estimated and a
relationship between current and constituent quark masses is obtained.Comment: 3 pages, style and typos corrected, more general case considered,
main results unchange
Energy composition of the Universe: time-independent internal symmetry
The energy composition of the Universe, as emerged from the Type Ia supernova
observations and the WMAP data, looks preposterously complex, -- but only at
the first glance. In fact, its structure proves to be simple and regular. An
analysis in terms of the Friedmann integral enables to recognize a remarkably
simple time-independent covariant robust recipe of the cosmic mix: the
numerical values of the Friedmann integral for vacuum, dark matter, baryons and
radiation are approximately identical. The identity may be treated as a
symmetry relation that unifies cosmic energies into a regular set, a quartet,
with the Friedmann integral as its common genuine time-independent physical
parameter. Such cosmic internal (non-geometrical) symmetry exists whenever
cosmic energies themselves exist in nature. It is most natural for a finite
Universe suggested by the WMAP data. A link to fundamental theory may be found
under the assumption about a special significance of the electroweak energy
scale in both particle physics and cosmology. A freeze-out model developed on
this basis demonstrates that the physical nature of new symmetry might be due
to the interplay between electroweak physics and gravity at the cosmic age of a
few picoseconds. The big `hierarchy number' of particle physics represents the
interplay in the model. This number quantifies the Friedmann integral and gives
also a measure to some other basic cosmological figures and phenomena
associated with new symmetry. In this way, cosmic internal symmetry provides a
common ground for better understanding of old and recent problems that
otherwise seem unrelated; the coincidence of the observed cosmic densities, the
flatness of the co-moving space, the initial perturbations and their amplitude,
the cosmic entropy are among them.Comment: 32 page
Cosmology and New Physics
A comparison of the standard models in particle physics and in cosmology
demonstrates that they are not compatible, though both are well established.
Basics of modern cosmology are briefly reviewed. It is argued that the
measurements of the main cosmological parameters are achieved through many
independent physical phenomena and this minimizes possible interpretation
errors. It is shown that astronomy demands new physics beyond the frameworks of
the (minimal) standard model in particle physics. More revolutionary
modifications of the basic principles of the theory are also discussed.Comment: 37 pages, 5 figures; lectures presented at 9th International Moscow
School of Physics (34th ITEP Winter School
A Pedagogical Review of Electroweak Symmetry Breaking Scenarios
We review different avenues of electroweak symmetry breaking explored over
the years. This constitutes a timely exercise as the world's largest and the
highest energy particle accelerator, namely, the Large Hadron Collider (LHC) at
CERN near Geneva, has started running whose primary mission is to find the
Higgs or some phenomena that mimic the effects of the Higgs, i.e. to unravel
the mysteries of electroweak phase transition. In the beginning, we discuss the
Standard Model Higgs mechanism. After that we review the Higgs sector of the
Minimal Supersymmetric Standard Model. Then we take up three relatively recent
ideas: Little Higgs, Gauge-Higgs Unification, and Higgsless scenarios. For the
latter three cases, we first present the basic ideas and restrict our
illustration to some instructive toy models to provide an intuitive feel of the
underlying dynamics, and then discuss, for each of the three cases, how more
realistic scenarios are constructed and how to decipher their experimental
signatures. Wherever possible, we provide enough pedagogical details, which the
beginners might find useful.Comment: 45 pages, Review based on a series of lectures; v2: 63 pages,
substantially expanded, references added, to appear in `Reports on Progress
in Physics
Search for Squarks and Gluinos in Events Containing Jets and a Large Imbalance in Transverse Energy
Using data corresponding to an integrated luminosity of 79 pb-1, D0 has
searched for events containing multiple jets and large missing transverse
energy in pbar-p collisions at sqrt(s)=1.8 TeV at the Fermilab Tevatron
collider. Observing no significant excess beyond what is expected from the
standard model, we set limits on the masses of squarks and gluinos and on the
model parameters m_0 and m_1/2, in the framework of the minimal low-energy
supergravity models of supersymmetry. For tan(beta) = 2 and A_0 = 0, with mu <
0, we exclude all models with m_squark < 250 GeV/c^2. For models with equal
squark and gluino masses, we exclude m < 260 GeV/c^2.Comment: 10 pages, 3 figures, Submitted to PRL, Fixed typo on page bottom of
p. 6 (QCD multijet background is 35.4 events
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