740 research outputs found
Quasi Exactly Solvable 22 Matrix Equations
We investigate the conditions under which systems of two differential
eigenvalue equations are quasi exactly solvable. These systems reveal a rich
set of algebraic structures. Some of them are explicitely described. An exemple
of quasi exactly system is studied which provides a direct counterpart of the
Lam\'e equation.Comment: 14 pages, Plain Te
Canonical and Lie-algebraic twist deformations of -Poincare and contractions to -Galilei algebras
We propose canonical and Lie-algebraic twist deformations of
-deformed Poincare Hopf algebra which leads to the generalized
-Minkowski space-time relations. The corresponding deformed
-Poincare quantum groups are also calculated. Finally, we perform the
nonrelativistic contraction limit to the corresponding twisted Galilean
algebras and dual Galilean quantum groups.Comment: 16 pages, no figures, v3: few changes provided - version for journal,
v2: submitted incidentally, v4: the page numbers for all references in
preprint version are provide
Field theory on --Minkowski space revisited: Noether charges and breaking of Lorentz symmetry
This paper is devoted to detailed investigations of free scalar field theory
on -Minkowski space. After reviewing necessary mathematical tools we
discuss in depth the Lagrangian and solutions of field equations. We analyze
the spacetime symmetries of the model and construct the conserved charges
associated with translational and Lorentz symmetry. We show that the version of
the theory usually studied breaks Lorentz invariance in a subtle way: There is
an additional trans-Planckian mode present, and an associated conserved charge
(the number of such modes) is not a Lorentz scalar.Comment: 22 pages, 1 figure, formulas in sect. III correcte
Psychological targeting as an effective approach to digital mass persuasion
People are exposed to persuasive communication across many different contexts: governments, companies, and political parties use persuasive appeals to encourage people to eat healthier, purchase a particular product, or vote for a specific candidate. Laboratory studies show that such persuasive appeals are more effective in influencing behavior when they are tailored to individualsâ unique psychological characteristics. Yet, the investigation of large-scale psychological persuasion in the real world has been hindered by the questionnaire-based nature of psychological assessment. Recent research, however, shows that peopleâs psychological characteristics can be accurately predicted from their digital footprints, such as their Facebook Likes or Tweets. Capitalizing on this new form of psychological assessment from digital footprints, we test the effects of psychological persuasion on peopleâs actual behavior in an ecologically valid setting. In three field experiments that reached over 3.5 million individuals with psychologically-tailored advertising, we find that matching the content of persuasive appeals to individualsâ psychological characteristics significantly altered their behavior as measured by clicks and purchases. Persuasive appeals that were matched to peopleâs extraversion or openness-to-experience level resulted in up to 40% more clicks and up to 50% more purchases than their mismatching or un-personalized counterparts. Our findings suggest that the application of psychological targeting makes it possible to influence the behavior of large groups of people by tailoring persuasive appeals to the psychological needs of the target audiences. We discuss both the potential benefits of this method for helping individuals make better decisions and the potential pitfalls related to manipulation and privacy
Scalar field theory on -Minkowski space-time and Doubly Special Relativity
In this paper we recall the construction of scalar field action on
-Minkowski space-time and investigate its properties. In particular we
show how the co-product of -Poincar\'e algebra of symmetries arises
from the analysis of the symmetries of the action, expressed in terms of
Fourier transformed fields. We also derive the action on commuting space-time,
equivalent to the original one. Adding the self-interaction term we
investigate the modified conservation laws. We show that the local interactions
on -Minkowski space-time give rise to 6 inequivalent ways in which
energy and momentum can be conserved at four-point vertex. We discuss the
relevance of these results for Doubly Special Relativity.Comment: 17 pages; some editing done, final version to be published in Int. J.
Mod. Phys.
Scalar field propagation in the phi^4 kappa-Minkowski model
In this article we use the noncommutative (NC) kappa-Minkowski phi^4 model
based on the kappa-deformed star product, ({*}_h). The action is modified by
expanding up to linear order in the kappa-deformation parameter a, producing an
effective model on commutative spacetime. For the computation of the tadpole
diagram contributions to the scalar field propagation/self-energy, we
anticipate that statistics on the kappa-Minkowski is specifically
kappa-deformed. Thus our prescription in fact represents hybrid approach
between standard quantum field theory (QFT) and NCQFT on the kappa-deformed
Minkowski spacetime, resulting in a kappa-effective model. The propagation is
analyzed in the framework of the two-point Green's function for low,
intermediate, and for the Planckian propagation energies, respectively.
Semiclassical/hybrid behavior of the first order quantum correction do show up
due to the kappa-deformed momentum conservation law. For low energies, the
dependence of the tadpole contribution on the deformation parameter a drops out
completely, while for Planckian energies, it tends to a fixed finite value. The
mass term of the scalar field is shifted and these shifts are very different at
different propagation energies. At the Planckian energies we obtain the
direction dependent kappa-modified dispersion relations. Thus our
kappa-effective model for the massive scalar field shows a birefringence
effect.Comment: 23 pages, 2 figures; To be published in JHEP. Minor typos corrected.
Shorter version of the paper arXiv:1107.236
-Deformation of Poincar\'e Superalgebra with Classical Lorentz Subalgebra and its Graded Bicrossproduct Structure
The -deformed Poincar{\'e} superalgebra written in Hopf
superalgebra form is transformed to the basis with classical Lorentz subalgebra
generators. We show that in such a basis the -deformed Poincare
superalgebra can be written as graded bicrossproduct. We show that the
-deformed superalgebra acts covariantly on -deformed
chiral superspace.Comment: 13 pages, late
Poincare covariant mechanics on noncommutative space
The Dirac approach to constrained systems can be adapted to construct
relativistic invariant theories on a noncommutative (NC) space. As an example,
we propose and discuss relativistic invariant NC particle coupled to
electromagnetic field by means of the standard term . Poincare
invariance implies deformation of the free particle NC algebra in the
interaction theory. The corresponding corrections survive in the
nonrelativistic limit.Comment: 7 pages, JHEP style, final versio
Women are warmer but no less assertive than men: gender and language on Facebook
Using a large social media dataset and open-vocabulary methods from computational linguistics, we explored differences in language use across gender, affiliation, and assertiveness. In Study 1, we analyzed topics (groups of semantically similar words) across 10 million messages from over 52,000 Facebook users. Most language differed little across gender. However, topics most associated with self-identified female participants included friends, family, and social life, whereas topics most associated with self-identified male participants included swearing, anger, discussion of objects instead of people, and the use of argumentative language. In Study 2, we plotted male- and female-linked language topics along two interpersonal dimensions prevalent in gender research: affiliation and assertiveness. In a sample of over 15,000 Facebook users, we found substantial gender differences in the use of affiliative language and slight differences in assertive language. Language used more by self-identified females was interpersonally warmer, more compassionate, polite, andâcontrary to previous findingsâslightly more assertive in their language use, whereas language used more by self-identified males was colder, more hostile, and impersonal. Computational linguistic analysis combined with methods to automatically label topics offer means for testing psychological theories unobtrusively at large scale.This work was supported by the Templeton Religion Trust
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