Riesz transforms and multipliers for the Bessel-Grushin operator

Víctor Almeida, Jorge J. Betancor, Alejandro J. Castro +1

We establish that the spectral multiplier $\mathfrak{M}(G_{\alpha })$ associated to the differential operator $$ G_α=- Δ_x +\sum_{j=1}^m{{α_j^2-1/4}\over{x_j^2}}-|x|^2 Δ_y \; \text{on} (0,\inf…