In this paper, we established compactness results for families of continuous functions in grand Lebesgue spaces $ G_\psi $, where $ \psi:(a, b)\to(0, \infty) $ is a given positive function that determines the structure of the space. In particular, we showed that equicontinuity together with uniform boundedness implies relative compactness in the $ G_\psi $-norm. The approach is based on Arzelà–Ascoli-type arguments combined with uniform control in grand Lebesgue space (GLS) norms. Several examples were provided to illustrate convergence mechanisms, and extensions to weighted GLS and fractional Sobolev-type settings are discussed. These results establish a unified compactness framework in grand Lebesgue spaces and provide a foundation for further investigations in Sobolev-type embeddings and related analytical models.
Citation: Rahma KATEA, Yasin KAYA. On the compactness of families of continuous functions in Grand Lebesgue spaces[J]. AIMS Mathematics, 2026, 11(5): 13647-13659. doi: 10.3934/math.2026562
In this paper, we established compactness results for families of continuous functions in grand Lebesgue spaces $ G_\psi $, where $ \psi:(a, b)\to(0, \infty) $ is a given positive function that determines the structure of the space. In particular, we showed that equicontinuity together with uniform boundedness implies relative compactness in the $ G_\psi $-norm. The approach is based on Arzelà–Ascoli-type arguments combined with uniform control in grand Lebesgue space (GLS) norms. Several examples were provided to illustrate convergence mechanisms, and extensions to weighted GLS and fractional Sobolev-type settings are discussed. These results establish a unified compactness framework in grand Lebesgue spaces and provide a foundation for further investigations in Sobolev-type embeddings and related analytical models.
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