Abstract
We give a complete classification of the irreducible quasifinite modules for algebras of the form Vir ⊗ A, where Vir is the Virasoro algebra and A is a finitely generated commutative associative unital algebra over the complex numbers. It is shown that all such modules are tensor products of generalized evaluation modules. We also give an explicit sufficient condition for a Verma module of Vir ⊗ A to be reducible. In the case that A is an infinite-dimensional integral domain, this condition is also necessary.
Similar content being viewed by others
References
M. F. Atiyah, I. G. Macdonald, Introduction to Commutative Algebra, Addison-Wesley, Reading, Mass., 1969. Russian transl.: М. Атья, И. Макдональд, Введенuе в коммуmаmuвную, Мир, 1972.
N. Bourbaki. Éléments de mathématique. 23. Premiére partie: Les structures fondamentales de l’analyse. Livre II: Algébre. Chapitre 8: Modules et anneaux semi-simples, Actualités Sci. Ind., no. 1261, Hermann, Paris, 1958. Russian transl.: Н. Бурбаки, Алгеьра. Модули, кольца, формы, Наука, М., 1966.
Y. Billig, K. Zhao. Weight modules over exp-polynomial Lie algebras, J. Pure Appl. Algebra 191 (2004), no. 1–2, 23–42.
V, Chari, G, Fourier, T, Khandai, A categorical approach to Weyl modules, Transform. Groups 15 (2010), no. 3, 517–549.
V. Chari, A. Pressley, Unitary representations of the Virasoro algebra and a conjecture of Kac, Compositio Math. 67 (1988), no. 3, 315–342.
X. Guo, R. Lu, K. Zhao, Classification of irreducible Harish-Chandra modules over generalized Virasoro algebras, to appear in Proc. Edinburgh Math. Soc., arXiv:math/0607614.
X. Guo, R. Lu, K. Zhao, Simple Harish-Chandra modules, intermediate series modules, and Verma modules over the loop-Virasoro algebra, Forum Math. 23 (2011), no. 5, 1029–1052.
J. Hu, X. Wang, K. Zhao, Verma modules over generalized Virasoro algebras Vir[G], J. Pure Appl. Algebra 177 (2003), no. 1, 61–69.
V. G. Kac, A. K. Raina, Bombay Lectures on Highest Weight Representations of Infinite-Dimensional Lie Algebras, Advanced Series in Mathematical Physics, Vol. 2, World Scientific, Teaneck, NJ, 1987.
H. Li. On certain categories of modules for affine Lie algebras, Math. Z. 248 (2004), no. 3, 635–664.
R. Lu, K. Zhao, Classification of irreducible weight modules over higher rank Virasoro algebras, Adv. Math. 206 (2006), no. 2, 630–656.
R. Lü, K. Zhao, Classification of irreducible weight modules over the twisted Heisenberg–Virasoro algebra, Commun. Contemp. Math. 12 (2010), no. 2, 183–205.
O. Mathieu, Classification of Harish-Chandra modules over the Virasoro Lie algebra, Invent. Math. 107 (1992), no. 2, 225–234.
V. Mazorchuk, Verma modules over generalized Witt algebras, Compositio Math. 115 (1999). no. 1, 21–35.
V. Mazorchuk, Classification of simple Harish-Chandra modules over Q-Virasoro algebra, Math. Nachr. 209 (2000), 171–177.
C. Martin. A. Piard, Indecomposable modules over the Virasoro Lie algebra and a conjecture of V. Kac, Comm. Math. Phys. 137 (1991), no. 1, 109–132.
C. Martin, A. Piard, Nonbounded indecomposable admissible modules over the Virasoro algebra, Lett. Math. Phys. 23 (1991), no. 4, 319–324.
18 C. Martin, A, Piard, Classification of the indecomposable bounded admissible modules over the Virasoro Lie algebra with weightspaces of dimension not exceeding two, Comm. Math. Phys. 150 (1992), no. 3, 465–493.
E. Neher, A. Savage, Extensions and block decompositions for finite-dimensional representations of equivariant map algebras, arXiv:1103.4367.
E. Neher, A. Savage, P. Senesi, Irreducible finite-dimensional representations of equivariant map algebras, Trans. Amer. Math. Soc., to appear, arXiv:0906.5189.
S. Eswara Rao, On representations of toroidal Lie algebras, in: Functional analysis VIII, Various Publ. Ser. (Aarhus), Vol. 47, Aarhus Univ., Aarhus, 2004, pp. 146–167.
Y. Su, Simple modules over the high rank Virasoro algebras, Comm. Algebra 29 (2001), no. 5, 2067–2080.
Y. Su, Classification of Harish-Chandra modules over the higher rank Virasoro algebras, Comm. Math. Phys. 240 (2003), no. 3. 539–551.
Author information
Authors and Affiliations
Corresponding author
Additional information
This work was supported by a Discovery Grant from the Natural Sciences and Engineering Research Council of Canada.
Rights and permissions
About this article
Cite this article
Savage, A. Classification of irreducible quasifinite modules over map Virasoro algebras. Transformation Groups 17, 547–570 (2012). https://doi.org/10.1007/s00031-012-9182-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00031-012-9182-9