2021/01/13 by Francesca Astengo, Astengo, Francesca, Bianca Di Blasio +3
Biochemistry, Genetics and Molecular Biology · Mathematics · #43A85 #43A90 #Advanced Algebra and Geometry #Dermatological and Skeletal Disorders #FOS: Mathematics #Functional Analysis (math.FA) #Holomorphic and Operator Theory
paper · pdf · doi:10.48550/arxiv.2101.05378
openalex publication_date 2021/01/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Let (G,K) be a Gelfand pair, with G a Lie group of polynomial growth, and let Σ⊂\mathbb R^ℓ be a homeomorphic image of the Gelfand spectrum, obtained by choosing a generating system D1,…,D_ℓ of G-invariant differential operators on G/K and associating to a bounded spherical function φ the ℓ-tuple of its eigenvalues under the action of the Dj's. We say that property (S) holds for (G,K) if the spherical transform maps the bi-K-invariant Schwartz space \mathcal S(K\backslash G/K) isomorphically onto \mathcal S(Σ), the space of restrictions to Σ of the Schwartz functions on \mathbb R^ℓ. This property is known to hold for many nilpotent pairs, i.e., Gelfand pairs where G=K\ltimes N, with N nilpotent. In this paper we enlarge the scope of this analysis outside the range of nilpotent pairs, stating the basic setting for general pairs of polynomial growth and then focussing on strong Gelfand pairs.