This book is devoted to inverse problems for determining the order in fractional partial differential equations, a subject of growing significance in modern analysis. This book presents a comprehensive collection of new results that address complex mathematical problems in a clear and structured manner. It provides profound theoretical insights supported by rigorous proofs, while also highlighting their practical relevance. These results are presented here for the first time in a unified and systematic book format. The book not only deepens the reader’s understanding of advanced mathematical techniques but also introduces novel tools that can be applied to a wide range of research problems.

Professor Ravshan Ashurov earned his Doctor of Science degree from Moscow State University in 1992. He has authored over 100 scientific papers and more than 20 articles specifically focused on inverse problems related to determining the fractional order of fractional derivatives. In addition, he has written several books and monographs. His research interests span fractional differential equations (both ordinary and partial), the spectral theory of differential operators, harmonic analysis, and wavelet transforms.

Ilyoskhuja Sulaymonov is a PhD candidate at the V.I. Romanovskiy Institute of Mathematics, Uzbekistan Academy of Sciences. He has published several scientific articles in international journals, and his academic interests include fractional differential equations, mathematical physics, and functional analysis.