TY - JOUR ID - 31329 TI - DEVELOPMENT IN STRING THEORY JO - Journal of Sciences, Islamic Republic of Iran JA - JSCIENCES LA - en SN - 1016-1104 Y1 - 1990 PY - 1990 VL - 1 IS - 3 SP - EP - DO - N2 - The string theory is a fast moving subject, both physics wise and in the respect of mathematics. In order to keep up with the discipline it is important to move with new ideas which are being stressed. Here I wish to give extracts from new papers of ideas which I have recently found interesting. There are six papers which are involved: I ."Strings formulated directly in 4 dimensions " A. N. Schellekens II. "Remarks on 40 strings" C.Bachas III. "Informal introduction to extended algebras and conformal field theories with c 1 " F.Ravanini IV. "Skein relations and braiding in topological gauge theory" and "Modular geometry and the classification of rational conformal field theories " S. Mukhi V. "Chern-Simons theories" E. Witten VI. "Duality and the rdl of nonperturbative effects on the world-sheet" J.Lauer, J.Mas and H.P. Nilles UR - https://jsciences.ut.ac.ir/article_31329.html L1 - https://jsciences.ut.ac.ir/article_31329_062117b22f8e7f0c121b25936d4d7e8f.pdf ER -