PT Journal
AU Chen, MC
   Li, XQ
   Liu, XG
   Medina, O
   Ratz, M
TI Modular invariant holomorphic observables
SO Physics Letters B
JI Phys. Lett. B
PY 2024
BP 138600
EP 13pp
VL 852
DI 10.1016/j.physletb.2024.138600
LA English
AB In modular invariant models of flavor, observables must be modular invariant. The observables discussed so far in the literature are functions of the modulus tau and its conjugate, (tau) over bar. We point out that certain combinations of observables depend only on tau , i.e. are meromorphic, and in some cases even holomorphic functions of tau. These functions, which we dub "invariants" in this Letter, are highly constrained, renormalization group invariant, and allow us to derive many of the models' features without the need for extensive parameter scans. We illustrate the robustness of these invariants in two existing models in the literature based on modular symmetries, Gamma(3) and Gamma(5). We find that, in some cases, the invariants give rise to robust relations among physical observables that are independent of tau. Furthermore, there are instances where additional symmetries exist among the invariants. These symmetries are relevant phenomenologically and may provide a dynamical way to realize symmetries of mass matrices.
ER