TY - JOUR

T1 - Loop corrections to superstring equations of motion

AU - Callan, Curtis Gove

AU - Lovelace, C.

AU - Nappi, C. R.

AU - Yost, S. A.

N1 - Funding Information:
It is well-known that the physical content of tree-level (classical) string theory can be extracted from conformally-invariant two-dimensional nonlinear sigma models. One way of revealing this connection is to interpret the coupling constants of the general sigma model as spacetime fields and the conformal invariance conditions on the coupling constants as spacetime equations of motion. In all cases that have been examined, the spacetime physics extracted in this way from conformal sigma models agrees with that extracted directly from classical string theory. Since algebraic and analytic methods for obtaining exact, nonperturbative results on two-dimensional conformal field theories exist, the deep reason for being interested in conformal 1 Supported in part by DOE grant DE-AC02-76ER-03072. 2 On leave from Rutgers University. Supported in part by NSF grant PHY-84-15534. 3 Supported in part by NSF grant PHY-80-19754. 4 Now at University of Florida, Gainsville. Supported in part by DOE grant DE-FG05-87ER-40272.

PY - 1988/10/17

Y1 - 1988/10/17

N2 - We extend to the O(32) superstring our program of renormalizing string theory by cancelling BRST anomalies between different genus worldsheets. We calculate all the anomalies arising to lowest nontrivial loop order and in general background fields. At tree level, string consistency requires the background fields to satisfy equations of motion which ensure the conformal invariance of the underlying sigma model. We implement loop anomaly cancellation by adding to these equations appropriate loop-order source terms which necessarily break conformal invariance. The procedure leads to consistent loop-corrected equations of motion which can be derived from a spacetime effective action. The loop-order terms in this action incorporate a number of crucial aspects of spacetime physics, including the interaction of the photon with the graviton and the interactions of the antisymmetric tensor field with the gauge field which are responsible for spacetime gauge anomaly cancellation. We take these results as compelling evidence that loop-corrected string theory is associated with sigma models which are not conformally invariant in the usual sense. An extended version of conformal invariance, whose deep structure has yet to be uncovered, presumably incorporates string loop physics.

AB - We extend to the O(32) superstring our program of renormalizing string theory by cancelling BRST anomalies between different genus worldsheets. We calculate all the anomalies arising to lowest nontrivial loop order and in general background fields. At tree level, string consistency requires the background fields to satisfy equations of motion which ensure the conformal invariance of the underlying sigma model. We implement loop anomaly cancellation by adding to these equations appropriate loop-order source terms which necessarily break conformal invariance. The procedure leads to consistent loop-corrected equations of motion which can be derived from a spacetime effective action. The loop-order terms in this action incorporate a number of crucial aspects of spacetime physics, including the interaction of the photon with the graviton and the interactions of the antisymmetric tensor field with the gauge field which are responsible for spacetime gauge anomaly cancellation. We take these results as compelling evidence that loop-corrected string theory is associated with sigma models which are not conformally invariant in the usual sense. An extended version of conformal invariance, whose deep structure has yet to be uncovered, presumably incorporates string loop physics.

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U2 - 10.1016/0550-3213(88)90565-2

DO - 10.1016/0550-3213(88)90565-2

M3 - Article

AN - SCOPUS:0007069689

SN - 0550-3213

VL - 308

SP - 221

EP - 284

JO - Nuclear Physics, Section B

JF - Nuclear Physics, Section B

IS - 2-3

ER -