Abstract
We demonstrate that all rational models of theN = 2 super Virasoro algebra are unitary. Our arguments are based on three different methods: we determine Zhu’s algebraA(H0) (for which we give a physically motivated derivation) explicitly for certain theories, we analyse the modular properties of some of the vacuum characters, and we use the coset realisation of the algebra in terms ofsu(2) and two free fermions. Some of our arguments generalise to the Kazama-Suzuki models indicating that all rationalN = 2 supersymmetric models might be unitary.
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Ahn, C.,Chung, S.,Tye, S.-H.: NewParafermon,su(2)CosetandN = 2 Superconformai Field Theories, Nucl. Phys.B365, 191–240 (1991)
Anderson, G., Moore, G.: Rationality in Conformai Field Theory. Commun. Math. Phys.117,441–450 (1988)
Blumenhagen, R., Eholzer, W., Honecker, A., Hornfeck, K., Hübel, R.: Coset Realization of UnifyingW-Algebras. Int. J. Mod. Phys.A10, 2367–2430 (1995)
Blumenhagen, R., Hübel, R.: A Note on Representations ofN = 2SW-Algebras. Mod. Phys. Lett.A9, 3193–3204 (1994)
Boucher, W., Friedan, D., Kent, A.: Determinant Formulae and Unitarity for theN = 2 Superconformai Algebras in Two Dimensions or Exact Results on String Compactification. Phys. Lett.B172, 316–322 (1986)
Bouwknegt, P., Schoutens, K.:W-Symmetry in Conformai Field Theory. Phys. Rep.223, 183–276 (1993)
Di Vecchia, P., Petersen, J.L., Yu, M., Zheng, H.B.: Explicit Construction of theN - 2 Superconformai Algebra. Phys. Lett.B174, 280–284 (1986)
Dörrzapf, M.: Analytic Expressions for Singular Vectors of theN = 2 Superconformai Algebra. Commun. Math. Phys.180, 195–232 (1996)
Dörrzapf, M.:Superconformai Field Theories and their Representations. Cambridge: PhD thesis (1995)
Dörrzapf, M.:Embedding Diagrams for Verma Modules of the N = 2Superconformai Algebra, (in preparation)
Dobrev, V.K.: Characters of Unitarizable Highest Weight Modules over theN = 2 Superconformal Algebras. Phys. Lett.B186, 43–51 (1987)
Dong, C, Li, H., Mason, G.: Twisted Representations of Vertex Operator Algebras. Preprint, qalg/9509025
Dong, C., Li, H., Mason, G.: Vertex Operator Algebras Associated to Admissible Representations ofsl 2. Commun. Math. Phys.184, 65–93 (1997)
Feigin, B.L., Fuchs, D.B.: Cohomology of some nilpotent subalgebras of the Virasoro and Kac-Moody Lie algebras. J. Geom. Phys.5, 209–235 (1988)
Gaberdiel, M.R.: Fusion in Conformai Field Theory as the Tensor Product of the Symmetry Algebra. Int. J. Mod. Phys.A9, 4619–4636 (1993)
Gaberdiel, M.R.: Fusion Rules of Chiral Algebras. Nucl. Phys.B417, 130–150 (1994)
Gaberdiel, M.R., Kausch, H.G.: A Rational Logarithmic Conformai Field Theory. Phys. Lett.B386, 131–137 (1996)
Gato-Rivera, B., Rosado, J.I.: New Interpretation for the Determinant Formulae of theN = 2 Superconformal Algebras. Preprint IMAFF-96-38, hep-th/9602166.
Goddard, P..Meromorphic Conformai Field Theory. In: V.G. Kac (ed.), “Infinite Dimensional Lie Algebras and Lie Groups”, Proceedings of the CIRM-Lumminy Conference 1988, Singapore: World Scientific, (1989)
Goddard, P., Kent, P., Olive, D.: Unitary Representations of the Virasoro and Super-Virasoro Algebras. Commun. Math. Phys.103, 105–119 (1986)
Graham, R.L., Knuth, D.E., Patashnik, O.:Concrete Mathematics, New York: Addison-Wesley, (1992)
Hecke, E.: Über einen Zusammenhang zwischen elliptischen Modulfunktionen und indefiniten quadratischen Formen. Nachrichten der K. Gesellschaft der Wissenschaften zu Göttingen, Mathematischphysikalische Klasse 1925, pp. 35–44
Hille, E.:Analytic Function Theory II, London: Blaisdell Publishing Company, (1962)
Höhn, G.:Selbstduale Vertexoperator-Superalgebren und das Babymonster, Bonn: PhD thesis, (1995)
Huitu, K., Nemeschansky, D., Yankielowicz, S.:N = 2 Supersymmetry, Coset Models and Characters. Phys. Lett.B246, 105–113 (1990)
Kac, V.G., Peterson, D.H.: Infinite-Dimensional Lie Algebras, Theta Functions and Modular Forms. Adv. in Math.53, 125–264 (1984)
Kac, V.G., Wakimoto, M.: Modular Invariant Representations of Infinite-Dimensional Lie Algebras and Superalgebras. Proc. Natl. Acad. Sci. USA85, 4956–4960 (1988)
Kac, V.G., Wakimoto, M.: Classification of Modular Invariant Representations of Affine Algebras. Adv. Series Math. Phys.7, 138–177 (1989)
Kac, V.G., Wang, W.: Vertex Operator Superalgebras and Their Representations. Contemp. Math.175, 161–191 (1994), (hep-th/9312065)
Kazama, Y., Suzuki, H.: NewN = 2 Superconformai Field Theories and Superstring Compactification. Nucl. Phys.B321, 232–268 (1989)
Kent, A.:Infinite Dimensional Algebras and the Conformai Bootstrap, Cambridge: PhD thesis, (1986)
Kiritsis, E.B.: Character Formulae and Structure of the Representations of theN = 1,N = 2 Superconformai Algebras. Int. J. Mod. Phys.A3, 1871–1906 (1988)
Malikov, F.G.: Verma Modules over Kac-Moody Algebras of Rank 2. Leningrad Math. J.2, 269–286 (1991)
Matsuo, Y.: Character Formula ofC < 1 Unitary Representation ofN = 2 Superconformai Algebra. Prog. Theor. Phys.77, 793–797 (1987)
Mathieu, P., Walten, M.A.: Fractional Level Kac-Moody Algebras and Non-Unitary Coset Conformai Theories. Prog. Theor. Phys.102, 229–254 (1990)
Nahm, W.: Quasi-Rational Fusion Products. Int. J. Mod. Phys.B8, 3693–3702 (1994)
Nekovar, J.: Private communication
Ravanini, F., Yang, S.-K.: Modular Invariance inN = 2 Superconformai Field Theories. Phys. Lett.B195, 202–208 (1987)
Schwimmer, A., Seiberg, N.: Comments on theN = 2, 3,4 Superconformai Algebras in Two Dimensions. Phys. Lett.B184, 191–196 (1987)
Vafa, C.: Toward Classification of Conformai Theories. Phys. Lett.B206, 421–426 (1988)
Watts, G.M.T.: Fusion in theW 3 Algebra. Commun. Math. Phys.171, 87–98 (1995)
Zhu,Y.: Vertex Operator Algebras, Elliptic Functions, and Modular Forms, PhD thesis, Yale University (1990), Modular Invariance of Characters of Vertex Operator Algebras, Journal AMS9,237-302 (1996)
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Eholzer, W., Gaberdiel, M.R. Unitarity of rationalN = 2 superconformal theories. Commun. Math. Phys. 186, 61–85 (1997). https://doi.org/10.1007/BF02885672
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DOI: https://doi.org/10.1007/BF02885672