Recent Submissions

  • The theory of F-rational signature 

    Smirnov, I.Autoridad BCAM; Tucker, K. (2024)
  • Moderately discontinuous homotopy 

    Fernández de Bobadilla, J.Autoridad BCAM; Heinze, S.; Pe Pereira, M. (2022-12)
  • Monodromy conjecture for semi-quasihomogeneous hypersurfaces 

    Blanco, G.; Budur, N.Autoridad BCAM; Van der Veer, R. (2021)
    We give a proof the monodromy conjecture relating the poles of motivic zeta functions with roots of b-functions for isolated quasihomogeneous hypersurfaces, and more generally for semi-quasihomogeneous hypersurfaces. We ...
  • Polar exploration of complex surface germs 

    da Silva, A.B.; Fantini, L.; Némethi, A.Autoridad BCAM; Pichon, A. (2021)
    We prove that the topological type of a normal surface singularity pX, 0q provides finite bounds for the multiplicity and polar multiplicity of pX, 0q, as well as for the combinatorics of the families of generic hyperplane ...
  • The dimension of the image of the Abel map associated with normal surface singularities 

    Nagy, J.; Némethi, A.Autoridad BCAM (2019)
    Let (X, o) be a complex normal surface singularity with rational homology sphere link and let Xe be one of its good resolutions. Fix an effective cycle Z supported on the exceptional curve and also a possible Chern class ...
  • Monodromy conjecture for log generic polynomials 

    Budur, N.Autoridad BCAM; Van der Veer, R. (2020)
    A log generic hypersurface in P n with respect to a birational modification of P n is by definition the image of a generic element of a high power of an ample linear series on the modification. A log very-generic ...
  • Uniform Lech's inequality 

    Ma, L.; Smirnov, I.Autoridad BCAM (2022)
    Let (R,m) be a Noetherian local ring, and let M be a finitely generated R-module of dimension d. We prove that the set [Formula presented] is bounded below by 1/d!e(R‾) where R‾=R/Ann(M). Moreover, when Mˆ is equidimensional, ...

    Budur, N.Autoridad BCAM; Fernández de Bobadilla, J.Autoridad BCAM; Le, Q.; Nguyen, D. (2022-01-01)
    We construct a spectral sequence converging to the cohomology with compact support of the m-th contact locus of a complex polynomial. The first page is explicitly described in terms of a log resolution and coincides with ...
  • Lower bounds on Hilbert-Kunz multiplicities and maximal F-signature 

    Jeffries, J.; Nakajima, Y.; Smirnov, I.Autoridad BCAM; Watanabe, K.; Yoshida, K. (2022)
    ABSTRACT. Hilbert–Kunz multiplicity and F-signature are numerical invariants of commutative rings in positive characteristic that measure severity of singularities: for a regular ring both invariants are equal to one and ...
  • Uniform Lech's inequality 

    Ma, L.; Smirnov, I.Autoridad BCAM (2022)
    Let (R,m) be a Noetherian local ring of dimension d ≥ 2. We prove that if e(R􏰊red) > 1, then the classical Lech’s inequality can be improved uniformly for all m-primary ideals, that is, there exists ε > 0 such that e(I) ...
  • Moderately Discontinuous Homology 

    Fernández de Bobadilla, J.Autoridad BCAM; Heinze, S.; Sampaio, J.E.; Pe Pereira, M. (2021-01-01)
    We introduce a new metric homology theory, which we call Moderately Discontinuous Homology, designed to capture Lipschitz properties of metric singular subanalytic germs. The main novelty of our approach is to allow ...
  • Linearization of holomorphic families of algebraic automor- phisms of the affine plane 

    Kuroda, S.; Kutzschebauch, F.; Pelka, T.R.Autoridad BCAM (2022-01-03)
    Let $G$ be a reductive group. We prove that a family of polynomial actions of $G$ on $\mathbb{C}^2$, holomorphically parametrized by an open Riemann surface, is linearizable. As an application, we show that a particular ...
  • The Abel map for surface singularities III: Elliptic germs 

    Nagy, J.; Némethi, A.Autoridad BCAM (2021-01-01)
    The present note is part of a series of articles targeting the theory of Abel maps associated with complex normal surface singularities with rational homology sphere links (Nagy and Némethi in Math Annal 375(3):1427–1487, ...
  • Delta invariant of curves on rational surfaces I. An analytic approach 

    Cogolludo-Agustín, J.I.; László, T.; Martín-Morales, J.; Némethi, A.Autoridad BCAM (2021-01-01)
    We prove that if (C, 0) is a reduced curve germ on a rational surface singularity (X, 0) then its delta invariant can be recovered by a concrete expression associated with the embedded topological type of the pair C X. ...
  • Parametrization simple irreducible plane curve singularities in arbitrary characteristic 

    Duc, N.H. (2020-01-01)
    We study the classification of plane curve singularities in arbitrary characteristic. We first give a bound for the determinacy of a plane curve singularity with respect to pararametrization equivalence in terms of its ...
  • Classification of Lipschitz simple function germs 

    Nguyen, N.; Ruas, M.; Trivedi, S. (2020-07-01)
    It was shown by Henry and Parusiński in 2003 that the bi-Lipschitz right equivalence of function germs admits moduli. In this article, we introduce the notion of Lipschitz simple function germ and present the complete ...
  • Image Milnor Number Formulas for Weighted-Homogeneous Map-Germs 

    Pallarés Torres, I.Autoridad BCAM; Peñafort Sanchis, Guillermo (2021-07-05)
    We give formulas for the image Milnor number of a weighted-homogeneous map-germ $(\mathbb{C}^n,0)\to(\mathbb{C}^{n+1},0)$, for $n=4$ and $5$, in terms of weights and degrees. Our expressions are obtained by a purely ...
  • Classification of smooth factorial affine surfaces of Kodaira dimension zero with trivial units 

    Pełka, T.; Raźny, P. (2021-07-31)
    We give a corrected statement of (Gurjar and Miyanishi 1988, Theorem 2), which classifies smooth affine surfaces of Kodaira dimension zero, whose coordinate ring is factorial and has trivial units. Denote the class of such ...
  • Some contributions to the theory of singularities and their characteristic classes 

    Pallarés Torres, I.Autoridad BCAM (2021-06-02)
    In this Ph.D. thesis, we give some contributions to the theory of singularities, as well as to the theory of characteristic classes of singular spaces. The first part of this thesis is devoted to the theory of singularities ...
  • Decomposition theorem and torus actions of complexity one 

    Agustin, M.; Langlois, K. (2020)
    We algorithmically compute the intersection cohomology Betti numbers of any complete normal algebraic variety with a torus action of complexity one.