CEMAT - Member

Members > PhD Members

Gracinda Gomes

Institutional Address

Faculdade de Ciências da Universidade de Lisboa
Av. Prof. Gama Pinto, 2
1649-003 LISBOA

Phone: +351 21 7904826 | Fax: +351 217954288 | Email: gmcunha@fc.ul.pt

Position

Full Professor, Faculdade de Ciências, Universidade de Lisboa

Area

Algebra and Computing

Principal Area

Semigroup Theory

Other Area

Languages, Automata and Computacional Algebra

Qualifications

Agregação em Matemática, Universidade de Lisboa, 2002
Equivalência ao Grau de Doutor em Matemática (Álgebra e Geometria), Faculdade de Ciências, Universidade de Lisboa, 1984
Doutoramento em Matemática, Universidade de St. Andrews, Reino Unido, 1983
Licenciatura em Matemática, Faculdade de Ciências, Universidade de Lisboa, 1978
Bacharelato em Matemática, Faculdade de Ciências, Universidade de Lisboa, 1976

Papers in International Journals

Gomes, Gracinda M. S.; Ana-Catarina C. Monteiro (2024) Formations and i-Fitting classes of inverse semigroups, congruences and languages . Semigroup Forum: 109 (1), 87-115.

Gomes, Gracinda M. S.; Ana-Catarina C. Monteiro (2023) Formations of orthodox semigroups . Semigroup Forum: 107, 651–679.

Gomes, Gracinda M. S.; Nobre, Isabel J. (2022) Formations of inverse semigroups . Semigroup Forum: 105, 217–243.

Gomes, Gracinda M. S.; Bernardo H. Fernandes (2021) A topological shuttle between inequalities and pseudoinequalities . Semigroup Forum: 102, no. 3, 916–924.

Gomes, Gracinda M. S.; Bernardo H. Fernandes (2021) omega sharp algebras . Communications in Algebra: 49 (9), 3969–3999.

Branco, Mário J. J.; Gomes, Gracinda M. S.; Pin, Jean-Éric; Soler-Escrivà, Xaro (2020) On formations of monoids . Journal of Pure and Applied Algebra: 224, no. 11, 106401, 24 pages.

Branco, Mário J. J.; Gomes, Gracinda M. S.; Silva, Pedro V. (2019) On the semigroup rank of a group . Semigroup Forum: 99, 568-578.

Branco, Mário J. J.; Gomes, Gracinda M. S.; Gould, Victoria; Wang, Yanhui (2018) Ehresmann monoids: adequacy and expansions . Journal of Algebra: 513, 344-367.

Araújo, João; Gomes, Gracinda M. S.; Bentz, Wolfram (2018) Congruences on direct products of transformation and matrix monoids . Semigroup Forum: 97, 384-416.

Branco, Mário J. J.; Gomes, Gracinda M. S.; Silva, Pedro V. (2017) Takahasi semigroups . Forum Mathematicum: 29(5), 1145-1161.

Gomes, Gracinda M. S.; Santa-Clara, Catarina; Soares, Filipa (2015) The semigroup ring of a restriction semigroup with an inverse skeleton . Semigroup Forum: 90 (2015), no. 2, 449–474.

Branco, Mário J. J.; Gomes, Gracinda M. S.; Gould, Victoria (2015) Ehresmann monoids . J. Algebra: 443, 349–382.

Gomes, Gracinda M. S.; Ruskuc, Nik (2014) John Macintosh Howie: Work and Legacy . Semigroup Forum: 89(1), 2-19.

Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Jesus, Manuel M. (2011) The cardinal and the idempotent number of various monoids of transformations on a finite chain . Bulletin of the Malaysian Mathematical Sciences Society: 34(1), 79–85.

Gomes, Gracinda M. S.; Gould, Victoria (2011) Left adequate and left Ehresmann monoids II . Journal of Algebra: 348(1), 171-195.

Branco, Mário J. J.; Gomes, Gracinda M. S.; Gould, Victoria (2011) Left adequate and left Ehresmann monoids . International Journal of Algebra and Computation: 21(7), 1259-1284.

Branco, Mário J. J.; Gould, Victoria; Gomes, Gracinda M. S. (2010) Extensions and covers for semigroups whose idempotents form a left regular band . Semigroup Forum: 81, 51-70.

Branco, Mário J. J.; Gomes, Gracinda M. S. (2009) The generalized Szendrei expansion of an R-unipotent semigroup . Acta Mathematica Hungarica: 123(1-2), 11-26.

Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Jesus, Manuel M. (2009) Congruences on monoids of transformations preserving the orientation on a finite chain . Journal of Algebra: 321(3), 743–757.

Fountain, John; Gomes, Gracinda M. S.; Gould, Victoria (2009) Membership of AvG for classes of finite weakly abundant semigroups . Periodica Mathematica Hungarica: 59(1), 9-36.

Fountain, John; Gomes, Gracinda M. S.; Gould, Victoria (2009) The free ample monoid . International Journal of Algebra and Computation: 19(4), 527-554.

Gomes, Gracinda M. S.; Gould, Victoria (2008) Fundamental semigroups having a band of idempotents . Semigroup Forum: 77, 279-299.

Gomes, Gracinda M. S.; Szendrei, Maria B. (2007) Even covers of left ample semigroups . Semigroup Forum: 74(2), 293-305.

Gomes, Gracinda M. S.; Maria B. Szendrei (2007) Almost factorizable weakly ample semigroups . Communications in Algebra: 35 (11), 3503-3523.

Gomes, Gracinda M. S. (2006) The generalized prefix expansion of a weakly left ample semigroup . Semigroup Forum: 72 (3), 387-403.

Fountain, John B.; Gomes, Gracinda M. S. (2006) Finite abundant semigroups in which the idempotents form a subsemigroup . Journal of Algebra: 295, 303-313.

Fountain, J.B.; Gomes, Gracinda M. S. (2006) Proper covers of ample monoids . Proc. Edinb. Math. Soc.: 49, 277-289.

Gomes, Gracinda M. S.; Pin, J.-E.; Sezinando, Helena (2006) Presentations of the Schützenberger product of n groups . Communications in Algebra: 34 (4), 1213-1235.

Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Jesus, Manuel M. (2005) Presentations for some monoids of partial transformations on a finite chain . Communications in Algebra: 33, 587-604.

Gomes, Gracinda M. S. (2005) Proper extensions of weakly left ample semigroups . Acta Math Hungarica: 109 (1-2), 33-51.

Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Jesus, Manuel M. (2005) Congruences on monoids of order-preserving or order-reversing transformations on a finite chain . Glasgow Mathematical Journal: 47, 413-424.

Auinger, K.; Gomes, Gracinda M. S.; Gould, V.; Steinberg, B. (2004) An application of a theorem of Ash to finite proper cover . Studia Logica: 78, 45-57.

Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Jesus, Manuel M. (2004) Presentations for Some Monoids of Injective Partial Transformations on a Finite Chain . Southeast Asian Bulletin of Mathematics: 28, 903-918.

Gomes, Gracinda M. S.; Gould, V. (2003) Finite proper covers in a class of finite semigroups with commuting idempotents . Semigroup Forum: 66, 433-454.

Gomes, Gracinda M. S.; Gould, Victoria (2001) Fundamental Ehresmann Semigroups . Semigroup Forum: 63 (1), 11-33.

Araújo, Isabel M.; Branco, Mário J. J.; Fernandes, Vítor Hugo; Gomes, Gracinda M. S.; Ruskuc, N. (2001) On generators and relations for unions of semigroups . Semigroup Forum: 63 (1), 49-62.

Fountain, John; Gomes, Gracinda M. S. (2000) Primitive inverse congruences on categorical semigroups . Proc. Edinburgh Math. Soc.: 43, 395-413.

Giraldes, Emília; Gomes, Gracinda M. S.; McAlister, D. B. (2000) On a class of lattice ordered inverse semigroups . J. Algebra: 230, 496-517.

Gomes, Gracinda M. S.; Gould, Victoria (2000) Graph expansions of unipotent monoids . Comm. Algebra: 28 (1), 447-463.

Gomes, Gracinda M. S.; Gould, Victoria (1999) Proper weakly left ample semigroups . Internat. J. Algebra Comput.: 9 (6), 721-739.

Fountain, John; Gomes, Gracinda M. S.; Gould, Victoria (1999) A Munn type representation for a class of E-semiadequate semigroups . J. Algebra: 218, 693-714.

Fountain, John; Gomes, Gracinda M. S.; Gould, Victoria (1999) Enlargements, semiabundancy and unipotent monoids . Comm. Algebra: 27 (2), 595-614.

Gomes, Gracinda M. S.; Szendrei, Mária B. (1998) Idempotent pure extensions of inverse semigroups via quivers . J. Pure Applied Algebra: 127, 15-38.

Gomes, Gracinda M. S.; Howie, John M. (1998) Semigroups with zero whose idempotents form a subsemigroup . Proc. Royal Soc. Edinburgh: 128A, 265-281.

Gomes, Gracinda M. S.; Howie, John M. (1996) A P-theorem for inverse semigroups with zero . Portugaliae Math.: 53 (3), 257-278.

Gomes, Gracinda M. S.; Howie, John M. (1995) Idempotent endomorphisms of an independence algebra of finite rank . Proc. Edinb. Math. Soc.: 38, 107-116.

Fountain, John; Gomes, Gracinda M. S. (1994) Proper left type-A covers . Portugaliae Math.: 51 (4), 305-319.

Gomes, Gracinda M. S. (1993) A characterisation of the group congruences on a semigroup . Semigroup Forum: 46, 48-53.

Fountain, J.B.; Gomes, Gracinda M. S. (1993) Proper left type-A monoids revisited . Glasgow Math. J.: 35, 293-306.

Gomes, Gracinda M. S.; Howie, J.M. (1992) On the ranks of certain semigroups of order-preserving transformations . Semigroup Forum: 45, 272-282.

Gomes, Gracinda M. S. (1992) Group congruences on eventually inverse semigroup . Portugal. Math.: 49 (4), 417-428.

Fountain, J.B.; Gomes, Gracinda M. S. (1992) Left proper E-dense monoids . J. Pure Appl. Algebra: 80, 1-27.

Fountain, J.B.; Gomes, Gracinda M. S. (1990) The Szendrei expansion of a semigroup . Mathematika: 37, 251-260.

Gomes, Gracinda M. S. (1988) Orthodox congruences on regular semigroups . Semigroup Forum: 37, 149-166.

Gomes, Gracinda M. S.; Howie, J.M. (1987) On the ranks of certain finite semigroups of transformations . Math. Proc. Cambridge Philos. Soc.: 101, 395-403.

Gomes, Gracinda M. S.; Howie, J.M. (1987) Nilpotents in finite symmetric inverse semigroups . Proc. Edinburgh Math. Soc.: 30, 383-395.

Gomes, Gracinda M. S. (1986) Some results on congruences on R-unipotent semigroups . Semigroup Forum: 33, 175-185.

Gomes, Gracinda M. S. (1986) The lattice of R-unipotent congruences on a regular semigroup . Semigroup Forum: 33, 159-173.

Gomes, Gracinda M. S. (1985) R-unipotent congruences on regular semigroups . Semigroup Forum: 31, 265-280.

Blyth, T. S.; Gomes, Gracinda M. S. (1983) On the compatibility of the natural order on a regular semigroup . Proc. Roy. Soc. Edinburgh: 94A, 79-84.

Gomes, Gracinda M. S. (1983) On left quasinormal orthodox semigroups . Proc. Roy. Soc. Edinburgh: 95A, 59-71.

Books

Gomes, Gracinda M. S. (2011) Anéis e Corpos - uma introdução . Textos de Matemática, DM-FCUL: 22.

Edition of Books

André, Jorge M.; Branco, Mário J. J.; Fernandes, Vítor Hugo; Fountain, John; Gomes, Gracinda M. S.; Meakin, John (2007) Semigroups and Formal Languages, (Proceedings - International Conference on Semigroups and Languages in honour of the 65th birthday of D.B. McAlister), Lisboa, July 2005 . World Scientific.

Araújo, Isabel M.; Branco, Mário J. J.; Fernandes, Vítor Hugo; Gomes, Gracinda M. S. (2004) Proceedings of the Workshop on Semigroups and Languages (Lisbon 2002) . World Scientific.

Gomes, Gracinda M. S.; Pin, J.-E.; Silva, P.V. (2002) Semigroups, Algorithms, Automata and Languages . World Scientific.

Almeida, Jorge; Gomes, Gracinda M. S.; Silva, Pedro V. (1996) Semigroups, Automata and Languages . World Scientific.

Seminars

International Conference on Semigroups - On the occasion of the 65th birthday of Mária Szendrei (Univ. Szeged, Hungary) (11/07/2018) Faculdade de Ciências da Universidade de Lisboa

All Kinds of Mathematics Remind me of You - Conference to celebrate the 70th Anniversary of Peter J Cameron (24/07/2017) Faculdade de Ciências da Universidade de Lisboa

Algebra Workshop 2014 - 34 years of CAUL (19/11/2014) Instituto para a Investigação Interdisciplinar da Universidade de Lisboa, July 21-23 July, 2014

Groups and Semigroups: Interactions and Computations (25/07/2011)

Workshop on Algebra and Logic (19/06/2009)

Almost factorizable weakly ample semigroups (14/07/2007) Second International Congress in Algebras and Combinatorics, Xi'an University of Architecture and Technology, China

Some classes of factorizable semigroups (12/06/2007) Universidade de Coimbra, Portugal

A walk through my work with J. Fountain on classes of (one sided) abundant semigroups (13/10/2006) Fountainfest "Semigroups, categories and automata", Universidade de York, Reino Unido

A class of abundant semigroups in the pseudovariety AvG (01/10/2006) Universidade de Szeged, Hungria

Extensões de semigrupos (16/03/2005) UNESP, São José do Rio Preto, Brasil

Semigrupos inversos - uma breve introdução (08/03/2005) UNESP, São José do Rio Preto, Brasil

Extensões próprias de semigrupos fracamente amplos à esquerda (20/02/2004)

Semigroups of partial mappings (01/07/2003) "Algebra and Discrete Mathematics - symmetries and ordered structures under the influence of model theory and combinatorics", Euresco Conference, Germany

Weakly left ample semigroups (01/06/2003) International Meeting on Semigroup Theory and Related Topics, Universidade do Minho, Braga, Portugal

Semigrupos fracamente amplos à esquerda (16/05/2003)

Coberturas de monóides fracamente amplos à esquerda (11/04/2003) Universidade do Porto, Portugal

Proper extensions of weakly left ample semigroups (01/01/2003) Alfréd Rényi Mathematics Institute, Hungarian Sciences Academy, Hungria

Proper extensions of weakly left ample semigroups (01/01/2003) Universidade de Szeged, Hungria

Ordens de reticulado naturais no monóide inverso livre (01/02/2002) Encontro Nacional da Sociedade Portuguesa de Matemática, Coimbra, Portugal

Linguagens, Semigrupos e Autómatos (01/01/2002) Universidade de Lisboa, Portugal

Relação entre semigrupos, autómatos e linguagens (01/09/2000) Encontro Nacional da Sociedade Portuguesa de Matemática, Açores, Portugal

Autómatos e semigrupos - o problema da complexidade de grupo (01/01/2000) Matemática Radical 2000, Universidade de Lisboa, Portugal

Semigrupos e congruências de grupo (17/12/1999) Universidade de Lisboa, Portugal

Semigrupos Categóricos (01/09/1999) V Encontro dos Algebristas Portugueses, Aveiro, Portugal

Primitive inverse congruences on categorical semigroups (01/07/1999) 2nd International Semigroup Conference, St. Petersburgh, Rússia

Extensões de semireticulados por monóides inversos, via categorias (01/01/1999) Universidade de Coimbra, Portugal

On categorical semigroups (01/01/1999) Universidade de St. Andrews, Reino Unido

Algumas classes de congruências em semigrupos com zero (01/01/1998) Universidade de Lisboa, Portugal

Semigroups with zero whose idempotents form a subsemigroup (01/01/1997) Universidade de Glasgow, Reino Unido

Idempotent pure extensions by inverse semigroups (01/01/1997) Universidade de Northern Illinois, U.S.A.

Extensions of semilattices by inverse semigroups (01/01/1997) Universidade de Marquette, U.S.A.

O semigrupo de Munn - o semigrupo bicíclico (01/01/1996) Universidade de Lisboa, Portugal

Weakly left ample monoids and proper covers (01/01/1996) Semigroups and their applications, Praga, República Checa

Algumas classes de semigrupos com zero (01/01/1996) Escola de Primavera sobre Álgebra, SPM/CIM, Coimbra, Portugal

E-semigroups with idempotent pure congruences (01/01/1994) Colloquium on Semigroups, Szeged, Hungria

Coberturas próprias de monóides tipo-A à esquerda (01/01/1992) Universidade de Lisboa, Portugal

Monóides tipo-A à esquerda próprios (01/01/1992) CAUL, Universidade de Lisboa, Portugal

A estrutura dos monóides tipo-A à esquerda próprios (01/01/1992) Universidade do Porto, Portugal

Sobre semigrupos E-densos e E-unitários (01/01/1991) Universidade de Lisboa, Portugal

Embedding proper left type-A monoids into semidirect products (01/01/1991) "Halbgruppentheorie", Oberwolfach, Alemanha

Coberturas E-densas de semigrupos E-densos e E-unitários (01/01/1990) Universidade de Lisboa, Portugal

Monóides E-densos próprios (01/01/1990) Jornadas Luso-Espanholas de Matemática, Évora, Portugal

Semigrupos inversos livres (01/01/1990) CAUL, Universidade de Lisboa, Portugal

Extensões de grupos por semireticulados (01/01/1989) Universidade de Lisboa, Portugal

Right type-A, right proper E-dense monoids (01/01/1989) Semigroups Workshop, St. Andrews, Reino Unido

Semigrupos tipo-A à direita próprios e E-densos (01/01/1989) CAUL, Universidade de Lisboa, Portugal

Congruências em semigrupos inversos (01/01/1989) Universidade de Coimbra, Portugal

Semigrupos tipo-A à direita (01/01/1989) Universidade do Porto, Portugal

Orthodox congruences on regular semigroups (01/01/1987) Mini-Conference on Semigroups, St. Andrews, Reino Unido

Orthodox congruences on regular semigroups (01/01/1987) Colloquium on Regular Semigroups, Szeged, Hungria

Conferences

Workshop on Semigroups 2012 (to remember John M. Howie on the occasion of his 76th birthday) (23/05/2012) Instituto para a Investigação Interdisciplinar da Universidade de Lisboa, Lisboa, Portugal, 23-25/05/2012 (Organizing Committee)

The second international congress in algebras and combinatorics, dedicated to the 70 birthday of Leonid A. Bokut (07/2007) Beijing, China, 6-11/07/2007 and Xi'an, China, 12-15/07/2007

Fountainfest "Semigroups, categories and automata", a conference celebrating John Fountain's 65th birthday and his mathematical achievements (12/10/2006) University of York, UK, 12-14/10/2006 (Invited Speaker)

Algebra and Discrete Mathematics - Symmetries and Ordered Structures under the Influence of Model Theory and Combinatorics (26/07/2003) Hattingen (near Essen), Germany, 26-31/07/2003 (Invited Speaker)

Structural Theory of Automata, Semigroups and Universal Algebra (07/07/2003) University of Montreal, Canada, 07-18/07/2003

International Meeting on Semigroup Theory and Related Topics (25/06/2003) University of Minho, Braga, Portugal, 25-28/06/2003 (Invited Speaker)

International Workshop on Semigroups and Languages (11/2002) CAUL, Lisbon, Portugal, 27-29/11/2002 (Organizing Committee)