1 Nicolae Popescu, PhD., D.Sc., Acad. Prof.

(born 22 September 1937, at Strehaia, in Romania, EU) is a Romanian mathematician. He was elected a Full Member of the Romanian Academy in 1992, three years after the liberation of Romania from dictatorship in 1989, and he is best known for his contributions to Abstract Algebra and the theory of Abelian categories, especially sheaf theory and category theory applications to commutative rings and modules. Since 1964 he collaborated on the characterization of Abelian categories with the well-known French mathematician Pierre Gabriel. His areas of expertise are: category theory focused on Abelian categories with applications to rings and modules, Adjoint Functors, limit functors and colimits, commutative ring theory, fields, polynomials, and Valuation Theory]; he also has strong interests and published in the following areas: algebraic topology, algebraic Geometry, Commutative Algebra, K–theory, Class-Field theory and Functional Analysis (Algebraic Function theory). He published between 1962 and 2009 over 112 papers in peer–reviewed, mathematics journals, several monographs on the theory of sheaves, and also six books on category theory and Abstract Algebra. In a Grothendieck–like, energetic style, he initiated and provided scientific leadership to several seminars on Category theory and Algebraic Geometry Seminars on Algebraic Geometry and Category theory, sheaves and abstract algebra which resulted in a continuous stream of high–quality mathematical publications in international, peer–reviewed mathematics journals by several members participating in his Seminar series.

1.1 Education

He earned his Master of Science (M.S.) degree in Mathematics in 1964, and his Doctor of Philosophy (Ph.D.) degree in mathematics in 1967, both at the University of Bucharest. He was awarded a D. Phil. degree (Doctor Docent) in 1972 by the University of Bucharest.

1.2 Current

Presently, he continues his mathematics studies at the Institute of Mathematics of the Romanian Academy in the Algebra research group, and also has international collaborations on four continents. One finds from conversations with Academician Nicolae Popescu that he shares many moral, ethical and religious values with another famous mathematician French–German–Jewish Alexander Grothendieck who visited the School of Mathematics in Bucharest in 1968. Like Grothendieck he has a long-standing interest in category theory, number theory, practicing Yoga, and supporting promising young mathematicians in his fields of interest. He also supported the early developments of category theory applications in mathematical biology, relational biology and mathematical biophysics.

1.3 Academic positions

Dr. Nicolae Popescu was appointed as a Lecturer (Assoc. Professor) at the University of Bucharest in 1968 where he taught mathematics graduate students until 1972. Since 1964, he also held a Research Professorship at the Institute of Mathematics of the Romanian Academy, which institute was ruthlessly eliminated by former dictator of S.R. Romania in 1976 for reasons related to his daughter Zoe Cheaushescu who was ‘hired’ by the Mathematics Institute in Bucharest two years before.

1.4 Selected Publications

1.4.1 Peer–reviewed articles

Nicolae Popescu. On the homology and homotopy of CW–complexes. (orig. title: “Asupra omologiei si omotopiei C.W. – complexelor”, Studii si cercetari Matem.., 1962. (with D. Burghelea)

Nicolae Popescu. Generalized Differential operators (orig. title: Diferentiale generalizate, Comunicarile Acad. R.S.Roumania., vol. 13, Nr. 6 (1963), 523-528. (with C. Banica)

Nicolae Popescu. Modules with generalized differentials (orig. title: Module cu diferentiala generalizata, St. Cerc. Mat., vol. 16, Nr. 6. (1964), 673-804. ; Modules avec différentielle généralisée. ” Rev. Roum. Math. Pures et Appl. Nr. 6 (1964)

Nicolae Popescu. Quelques considérations sur l’exactitude des foncteurs, Bull. Math. Soc. Sci. Math. Phys. de la R. P. Roumanie. 7 (1963), 144-147. (with C. Banica).

Nicolae Popescu. Quotient categories (orig. title: Categorii ct), St. Cerc. Matem. 17, (1965), 951-985. (with C. Banica)

(in fr.) Sur les catégories preabéliens., Rev. Roum. Math. Pures Appl., 10, (1965), 621-633. (with C. Banica)

Nicolae Popescu. (lang.fr). Caractérisation des catégories abéliennes avec générateurs et limites inductives exactes., C. R. Acad. Sci. Paris. 258 (1964), 4188–4191. (with Pierre Gabriel).

Nicolae Popescu. (lang.fr.) La localisation pour des sites., Rev. Roum. Math. Pures et Appl. 10, (1965), 1031–1044.

Nicolae Popescu. La structure des modules injectifs sur an anneau á idéal principal, Bull. Math. de la Soc. Sci. Math. Phys. de la R . P.Roumanie vol.8 (56), Nr. 1–2 (1964), 67–73. (with A. Radu)

Nicolae Popescu. Morphismes et co-morphismes des topos abéliennes, Bull. Math. de la Soc. Sci. Math. de la R.S. Roumanie. vol 10(58) W.2–4 (1996), 319–328. (with A. Radu).

Nicolae Popescu. (lang.fr.) Sur la structure des objets de certaines catégories abéliennes., C.R. Acad. Sci. Paris, 262 (1966), 1295–1297. (with C. Nastasescu)

Nicolae Popescu. (lang.fr.) Quelques observations sur les topes abéliennes., Rev. Roum. Math. Pures Appl. 12 (1967), 553–563. (with C. Nastasescu)

Nicolae Popescu. (lang.fr.) Théorie générale de la décomposition., Rev. Roum Math. Pures et Appl. 12 (1967), 1365–1371.

Nicolae Popescu. Les anneaux semi–artiniens, Bull. Soc. Math. France, 96 (1968) 357-368. (with C. Nastasescu).

Nicolae Popescu. Sur les epimorphismes plants d’anneaux, C.R. Acad. Sci. Paris, 268 (1969) 376-379. (with T. Spircu).

Nicolae Popescu. On the localization ring of ring., J. of Algebra , 15 (1970) 41-56. (with C. Nastasescu)

Nicolae Popescu.(lang.fr). Quelques observations sur les morphismes plats des anneaux., J. Algebra , 16, (1970), 40–59. (with T. Spircu)

Nicolae Popescu.(lang.fr). Le spectre gauche d’un anneau, J. Algebra , 18, (1971) 213–228.

Nicolae Popescu.(lang.fr). Les quasi-ordres (á gauche) des anneaux, J. Algebra, 17, (1971), 474–481. (with D. Spulber)

Les anneaux semi-noethÃriens, C.R. Acad. Sci. Paris 272 (1971), 1439-1441.

Sur les C. P. anneaux, C.R. Acad. Sci. Paris 272 (1971) 1493–1496.

Théorie de la décomposition primaire dans les anneaux semi-noethériens, J. Algebre 2399172, 482–492.

Some remarks about semi–artinian rings, Rev. Roumaine Math. Pures et Appl. 17, nr. 9(1973), 1413–1422. (with C. Vraciu)

lang. fr. Exemple de inele semi-artiniene, St. Cerc. Math. 26, nr.8 (1974), 1153-1157. (with T. Spircu)

Quelques considérations sur les anneaux semi–artiniéns commutatifs, C. R. Acad. Sci. Paris, 276 (1973), 1545–1548.

Permanence theorems for semi–artinian rings, Rev. Roum. Math. Pures et Appl. 21, nr.2 (1976), 227–231. (with T. Spircu)

lang.fr. Sur la Structure des Anneaux Absolument plats commutatifs, J. Algebra 40 (1976), 364-383. (with C. Vraciu)

Sur l’anneau des quotients d’un anneau noethérien (á droite) par rapport au système localisant associée à un idéal bilatéral premier, C.R. Acad. Sci. Paris.

Some remarks about the regular ring associated to a commutative ring, Rev. Roumaine Math. Pures et Appl. 23(1978), 269–277. (with C. Vraciu)

Sur la sous–catégorie localisant associée a un idéal bilatéral premier dans un anneau noethérien (à droite), Rev. Roum. Math. Pures et Appl. T. XXVi, nr. 7 (1981), 1033–1042.

Sur une classe de polynomes irréductibles, C.R. Acad. Sci. Paris, t. 297 (1983), 9–11.