In physics, the Polyakov action is an action of the two-dimensional conformal field theory describing the worldsheet of a string in string theory. It was introduced by Stanley Deser and Bruno Zumino and independently by L. Brink, P. Di Vecchia and P. S. Howe in 1976,[1][2] and has become associated with Alexander Polyakov after he made use of it in quantizing the string in 1981.[3] The action reads:
where is the string tension, is the metric of the target manifold, is the worldsheet metric, its inverse, and is the determinant of . The metric signature is chosen such that timelike directions are + and the spacelike directions are −. The spacelike worldsheet coordinate is called , whereas the timelike worldsheet coordinate is called . This is also known as the nonlinear sigma model.[4]
The Polyakov action must be supplemented by the Liouville action to describe string fluctuations.
^Deser, S.; Zumino, B. (1976). "A Complete Action for the Spinning String". Phys. Lett. B. 65 (4): 369–373. doi:10.1016/0370-2693(76)90245-8.
^Brink, L.; Di Vecchia, P.; Howe, P. (1976). "A locally supersymmetric and reparametrization invariant action for the spinning string". Physics Letters B. 65 (5): 471–474. doi:10.1016/0370-2693(76)90445-7.
^Polyakov, A. M. (1981). "Quantum geometry of bosonic strings". Physics Letters B. 103 (3): 207–210. doi:10.1016/0370-2693(81)90743-7.
^Friedan, D. (1980). "Nonlinear Models in 2+ε Dimensions" (PDF). Physical Review Letters. 45 (13): 1057–1060. Bibcode:1980PhRvL..45.1057F. doi:10.1103/PhysRevLett.45.1057.
In physics, the Polyakovaction is an action of the two-dimensional conformal field theory describing the worldsheet of a string in string theory. It was...
can be said to be defined by the path integral quantization of the Polyakovaction: I 0 [ g , X ] = T 8 π ∫ M d 2 ξ g g m n ∂ m x μ ∂ n x ν G μ ν ( x...
Alexander Markovich Polyakov (Russian: Алекса́ндр Ма́ркович Поляко́в; born 27 September 1945) is a Russian theoretical physicist, formerly at the Landau...
< 2 π {\displaystyle 0\leq \sigma <2\pi } . In order to define the Polyakovaction, the world-sheet is equipped with a world-sheet metric g {\displaystyle...
symmetry in conformal field theory. It is, for example, a symmetry of the Polyakovaction. When quantum mechanical effects break the conformal invariance of...
string theory. These theories are without supersymmetry. Polyakovaction Nambu-Goto action Bosonic string theory Kondo model (s-d model) Minimal model...
bosonic string theory. String theory is formulated in terms of the Polyakovaction, which describes how strings move through space and time. Like springs...
superstring revolution String theory landscape Theory Nambu–Goto actionPolyakovaction Bosonic string theory Superstring theory Type I string Type II string...
superstring revolution String theory landscape Theory Nambu–Goto actionPolyakovaction Bosonic string theory Superstring theory Type I string Type II string...
superstring revolution String theory landscape Theory Nambu–Goto actionPolyakovaction Bosonic string theory Superstring theory Type I string Type II string...
superstring revolution String theory landscape Theory Nambu–Goto actionPolyakovaction Bosonic string theory Superstring theory Type I string Type II string...
superstring revolution String theory landscape Theory Nambu–Goto actionPolyakovaction Bosonic string theory Superstring theory Type I string Type II string...
expected; it occurs in a situation where quantum effects should describe these actions, due to the extremely high density and therefore particle interactions...
superstring revolution String theory landscape Theory Nambu–Goto actionPolyakovaction Bosonic string theory Superstring theory Type I string Type II string...
superstring revolution String theory landscape Theory Nambu–Goto actionPolyakovaction Bosonic string theory Superstring theory Type I string Type II string...
superstring revolution String theory landscape Theory Nambu–Goto actionPolyakovaction Bosonic string theory Superstring theory Type I string Type II string...