I got my PhD in 1990 at the University of Barcelona (UB) under the supervision of G. Welters, in the area of algebraic geometry. In 1993 I got a position as Associate Professor at the UB, and in 2025 a position as Professor. My main collaborators are G.P. Pirola (U. Pavia), M. Lahoz (UB), P. Frediani (U. Pavia), E. Colombo (U. Milano), M.A. Barja (UPC), A. Ortega (Humboldt U.), I. Spelta (Humboldt U.) and A. Rojas (UB). I have been PI of several projects of the Spanish Ministry of Science and of the Catalan Government, and I have been invited to speak at academic institutions in Japan, Sweden, Germany, Argentina, Chile, Italy and Great Britain, among others.
Regarding teaching, I have taught doctoral, master’s and undergraduate courses at the UB and the BGSMath, as well as doctoral courses at international summer schools in Milano, Catania (Pragmatic) and Chile. I have supervised or co-supervised 6 doctoral theses, 5 master’s theses and 15 undergraduate theses.
Personal webpage: https://sira.ub.edu/static/fitxes/MatematiquesInformatica.html?id=jcnaranjo.ub.edu&lang=en
Abelian varieties and their moduli
Curves and their Jacobians
Algebraic cycles
Irregular varieties
Degree of irrationality of algebraic varieties
Birational Geometry, Group Actions, and Moduli Spaces, PID2023-147642NB-I00, Ministerio de Ciencia e Innovación (1 Sep 2024 – 31 Aug 2028). PIs: Martí Lahoz Vilalta and Juan Carlos Naranjo del Val
E. Colombo, P. Frediani, J.C. Naranjo, G.P. Pirola. On the local geometry of the moduli space of (2,2)-threefolds in 𝒜₉. Revista Matemática Iberoamericana (3) (2025).
J.C. Naranjo, A. Ortega, I. Spelta. Cyclic coverings of genus 2 curves of Sophie Germain type. Forum of Mathematics, Sigma 12 (2024).
M. Lahoz, J.C. Naranjo, A. Rojas. Geometry of Prym semicanonical pencils and an application to cubic threefolds. Mathematische Nachrichten (7), 2918–2941 (2022).
E. Colombo, O. Martin, J.C. Naranjo, G.P. Pirola. Degree of irrationality of a very general Abelian variety. International Mathematics Research Notices (11), 8295–8313 (2022).
J.C. Naranjo, A. Ortega. Global Prym-Torelli for double coverings ramified in at least six points. Journal of Algebraic Geometry (2), 387–396 (2022).
E. Colombo, J.C. Naranjo, G.P. Pirola. On the dimension of Voisin sets in the moduli space of abelian varieties. Mathematische Annalen 381, 91–104 (2021).
P. Frediani, J.C. Naranjo, I. Spelta. The fibers of the ramified Prym map. Communications in Contemporary Mathematics (5) (2021).
J.C. Naranjo, A. Ortega, A. Verra. Generic injectivity of the Prym map for double ramified coverings. Transactions of the American Mathematical Society (5), 3627–3646 (2019).
J.C. Naranjo, G.P. Pirola. Hyperelliptic Jacobians and isogenies. Advances in Mathematics 335, 896–909 (2018).