3,634 research outputs found
Correspondence principle in quantum gravity
The problem of consistent formulation of the correspondence principle in
quantum gravity is considered. The usual approach based on the use of the
two-particle scattering amplitudes is shown to be in disagreement with the
classical result of General Relativity given by the Schwarzschild solution. It
is shown also that this approach fails to describe whatever non-Newtonian
interactions of macroscopic bodies. An alternative interpretation of the
correspondence principle is given directly in terms of the effective action.
Gauge independence of the \hbar^0 part of the one-loop radiative corrections to
the gravitational form factors of the scalar particle is proved, justifying the
interpretation proposed. Application to the black holes is discussed.Comment: Talk presented at the international meeting "Quantum Gravity and
Spectral Geometry", Naples, July 2001. 4 pages, 1 figur
Carter-Saito theorem for virtual knots
In the article we construct new non-trivial state-sum invariants of virtual
knots and links using a generalization of the Carter-Saito theorem for
classical knots
Two-Matrix model with ABAB interaction
Using recently developed methods of character expansions we solve exactly in
the large N limit a new two-matrix model of hermitean matrices A and B with the
action S={1\over 2}(\tr A^2+\tr B^2)-{\alpha\over 4}(\tr A^4+\tr B^4)
-{\beta\over 2} \tr(AB)^2. This model can be mapped onto a special case of the
8-vertex model on dynamical planar graphs. The solution is parametrized in
terms of elliptic functions. A phase transition is found: the critical point is
a conformal field theory with central charge c=1 coupled to 2D quantum gravity.Comment: harvmac, 24 pages, 5 figures (1 color figure
Analytical treatment of 2D steady flames anchored in high-velocity streams
The problem of burning of high-velocity gas streams in channels is revisited.
Previous treatments of this issue are found to be incomplete. It is shown that
despite relative smallness of the transversal gas velocity, it plays crucial
role in determining flame structure. In particular, it is necessary in
formulating boundary conditions near the flame anchor, and for the proper
account of the flame propagation law. Using the on-shell description of steady
anchored flames, a consistent solution of the problem is given. Equations for
the flame front position and gas-velocity at the front are obtained. It is
demonstrated that they reduce to a second-order differential equation for the
front position. Numerical solutions of the derived equations are found.Comment: 15 pages, 6 figure
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