210 research outputs found
Anomalies, Local Counter Terms and Bosonization
We re-examine the issue of local counter terms in the analysis of quantum
anomalies. We analyze two-dimensional theories and show that the notion of
local counter terms need to be carefully defined depending on the physics
contents such as whether one is analyzing gauge theory or bosonization. It is
shown that a part of the Jacobian, which is apparently spurious and eliminated
by a local counter term corresponding to the mass term of the gauge field in
gauge theory, cannot be removed by a {\it local} counter term and plays a
central role by giving the kinetic term of the bosonized field in the context
of path integral bosonization.Comment: 24 pages, A contribution to the Hidenaga Yamagishi commemorative
volume of Physics Reports, edited by E. Witten and I. Zahed. Some sentences
were made more precise, and a Note Added was adde
CP breaking in lattice chiral gauge theory
The CP symmetry is not manifestly implemented for the local and doubler-free
Ginsparg-Wilson operator in lattice chiral gauge theory. We precisely identify
where the effects of this CP breaking appear.Comment: 3 pages, Lattice2002(chiral
Ginsparg-Wilson operators and a no-go theorem
If one uses a general class of Ginsparg-Wilson operators, it is known that CP
symmetry is spoiled in chiral gauge theory for a finite lattice spacing and the
Majorana fermion is not defined in the presence of chiral symmetric Yukawa
couplings. We summarize these properties in the form of a theorem for the
general Ginsparg-Wilson relation.Comment: 8 pages, Latex, references updated, version to appear in Phys. Lett.
More about the axial anomaly on the lattice
We study the axial anomaly defined on a finite-size lattice by using a Dirac
operator which obeys the Ginsparg-Wilson relation. When the gauge group is
U(1), we show that the basic structure of axial anomaly on the infinite
lattice, which can be deduced by a cohomological analysis, persists even on
(sufficiently large) finite-size lattices. For non-abelian gauge groups, we
propose a conjecture on a possible form of axial anomaly on the infinite
lattice, which holds to all orders in perturbation theory. With this
conjecture, we show that a structure of the axial anomaly on finite-size
lattices is again basically identical to that on the infinite lattice. Our
analysis with the Ginsparg-Wilson Dirac operator indicates that, in appropriate
frameworks, the basic structure of axial anomaly is quite robust and it
persists even in a system with finite ultraviolet and infrared cutoffs.Comment: 12 pages, uses JHEP.cls and amsfonts.sty, the final version to appear
in Nucl. Phys.
Topological Obstruction in Block-spin Transformations
Block-spin transformations from a fine lattice to a coarse one are shown to
give rise to a one-to-one correspondence between the zero-modes of the
Ginsparg-Wilson Dirac operators. The index is then preserved under the blocking
process. Such a one-to-one correspondence is violated and the block-spin
transformation becomes necessarily ill-defined when the absolute value of the
index is larger than 2rN, where N is the number of the sites on the coarse
lattice and r is the dimension of the gauge group representation of the fermion
variables.Comment: 11 pages, latex, no figure
Hawking Radiation from Charged Black Holes via Gauge and Gravitational Anomalies
Extending gr-qc/0502074, we show that in order to avoid a breakdown of
general covariance and gauge invariance at the quantum level the total flux of
charge and energy in each outgoing partial wave of a charged quantum field in a
Reissner-Nordstrom black hole background must be equal to that of a (1+1)
dimensional blackbody at the Hawking temperature with the appropriate chemical
potential.Comment: 4 pages, typos corrected, references added, version to appear in
Phys. Rev. Let
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