6,678 research outputs found
Realization of Vector fields for Quantum Groups as Pseudodifferential Operators on Quantum Spaces
The vector fields of the quantum Lie algebra are described for the quantum
groups and as pseudodifferential operators on the
linear quantum spaces covariant under the corresponding quantum group. Their
expressions are simple and compact. It is pointed out that these vector fields
satisfy certain characteristic polynomial identities. The real forms
and are discussed in detail.Comment: 16 pages, Latex, no figures, to appear in the Proceedings of the XX
International Conference on Group Theory Methods in Physics, Toyonaka, Japan
(1994
A Note on the Chiral Anomaly in the AdS/CFT Correspondence and 1/N^2 Correction
According to the AdS/CFT correspondence,the d=4, N=4 SU(N) SYM is dual to the
Type IIB string theory compactified on AdS_5xS^5. A mechanism was proposed
previously that the chiral anomaly of the gauge theory is accounted for to the
leading order in N by the Chern-Simons action in the AdS_5 SUGRA. In this
paper, we consider the SUGRA\string action at one loop and determine the
quantum corrections to the Chern-Simons action. While gluon loops do not modify
the coefficient of the Chern-Simons action, spinor loops shift the coefficient
by an integer. We find that for finite N, the quantum corrections from the
complete tower of Kaluza-Klein states reproduce exactly the desired shift N^2
---> N^2- 1 of the Chern-Simons coefficient, suggesting that this coefficient
does not receive corrections from the other states of the string theory. We
discuss why this is plausible.Comment: 12 pages, LaTex. Please send any comment to [email protected]; v2: one
reference added (to appear in Nucl. Phys. B
Instanton String and M-Wave in Multiple M5-Branes System
We consider the non-abelian self-dual two-form theory arXiv:1203.4224 and
find new exact solutions. Our solutions are supported by Yang-Mills
(anti)instantons in 4-dimensions and describe wave moving in null directions.
We argue and provide evidence that these instanton string solutions correspond
to M-wave (MW) on the worldvolume of multiple M5-branes. When dimensionally
reduced on a circle, the MW/M5 system is reduced to the D0/D4 system with the
D0-branes represented by the Yang-Mills instanton of the D4-branes Yang-Mills
gauge theory. We show that this picture is precisely reproduced by the
dimensional reduction of our instanton string solutions.Comment: 12 pages. LaTe
Dilaton, Screening of the Cosmological Constant and IR-Driven Inflation
It is known that infrared (IR) quantum fluctuations in de Sitter space could
break the de Sitter symmetry and generate time dependent observable effects. In
this paper, we consider a dilaton-gravity theory. We find that gravitational IR
effects lead to a time dependent shift on the vev of the dilaton and results in
a screening (temporal) of the cosmological constant/Hubble parameter. In the
Einstein frame, the effect is exponentiated and can give rises to a much more
notable amount of screening. Taking the dilaton as inflaton, we obtain an
inflationary expansion of the slow roll kind. This inflation is driven by the
IR quantum effects of de Sitter gravity and does not rely on the use of a slow
roll potential. As a result, our model is free from the eta problem which
baffles the standard slow roll inflation models.Comment: 41 pages. 4 figures. v3: Comments on the resummation, quantum
corrections to the Friedman equation and an issue of gauge dependence added.
References added. Version to appear in JHE
- …