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A bstract We construct a map between a class of codes over F 4 and a family of non-rational Narain CFTs. This construction is complementary to a recently introduced relation between quantum stabilizer codes and a class of rational Narain theories. From the modular bootstrap point of view we formulate a polynomial ansatz for the partition function which reduces modular invariance to a handful of algebraic easy-to-solve constraints. For certain small values of central charge our construction yields optimal theories, i.e. those with the largest value of the spectral gap.
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This content will become publicly available on July 24, 2026
Recursive spectral relations and the charge versus neutral gap in fractional quantum Hall systems
We consider quantum lattice Hamiltonians and derive recursive spectral relations bridging successive particle number sectors. One relation gives conditions under which the charge gap dominates the neutral gap. We verify these conditions under a triad of symmetries (translation-invariance, charge and dipole conservation) that are present, e.g., in periodic fractional quantum Hall systems. Thus, this gap domination, previously observed numerically, is a universal feature imposed by symmetry. A second relation yields a new induction-on-particle-number method for deriving spectral gaps. The results cover both bosons and fermions.
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- Award ID(s):
- 2108390
- PAR ID:
- 10645113
- Publisher / Repository:
- arXiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- University of California, Davis
- Sponsoring Org:
- National Science Foundation
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