ON SYMMETRIC REPRESENTATIONS OF SL2(ℤ)
Document Type
Article
Publication Date
4-1-2023
Abstract
We introduce the notions of symmetric and symmetrizable representations of SL2(ℤ). The linear representations of SL2(ℤ) arising from modular tensor categories are symmetric and have congruence kernel. Conversely, one may also reconstruct modular data from finite-dimensional symmetric, congruence representations of SL2(ℤ). By investigating a ℤ/2ℤ-symmetry of some Weil representations at prime power levels, we prove that all finite-dimensional congruence representations of SL2(ℤ) are symmetrizable. We also provide examples of unsymmetrizable noncongruence representations of SL2(ℤ) that are subrepresentations of a symmetric one.
Publication Source (Journal or Book title)
Proceedings of the American Mathematical Society
First Page
1415
Last Page
1431
Recommended Citation
Ng, S., Wang, Y., & Wilson, S. (2023). ON SYMMETRIC REPRESENTATIONS OF SL2(ℤ). Proceedings of the American Mathematical Society, 151 (4), 1415-1431. https://doi.org/10.1090/proc/16205