A5041155608- Algebraic Geometry and Number Theory
- Advanced Algebra and Geometry
- Geometry and complex manifolds
- Homotopy and Cohomology in Algebraic Topology
- Nonlinear Waves and Solitons
- Algebraic structures and combinatorial models
- Astrophysical Phenomena and Observations
- Geometric and Algebraic Topology
- Advanced Topics in Algebra
- Geometric Analysis and Curvature Flows
- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Advanced Differential Equations and Dynamical Systems
- Tensor decomposition and applications
- Black Holes and Theoretical Physics
- Stellar, planetary, and galactic studies
- Advanced Numerical Analysis Techniques
- Laser-Plasma Interactions and Diagnostics
- Astronomy and Astrophysical Research
- Polynomial and algebraic computation
- Finite Group Theory Research
- Classical Antiquity Studies
- Analytic and geometric function theory
- solar cell performance optimization
- Adaptive optics and wavefront sensing
Institute of Mathematical Sciences
2012-2024
Consejo Superior de Investigaciones Científicas
2011-2024
Universidad Carlos III de Madrid
2012-2024
Universidad Autónoma de Madrid
2013-2024
Universidad Complutense de Madrid
2000-2012
American Association of Variable Star Observers
2011
Imperial College London
2009
Instituto de Física Fundamental
2006-2007
Unidades Centrales Científico-Técnicas
2007
Tata Institute of Fundamental Research
1999-2002
Abstract We systematically surveyed period variations of superhumps in SU UMa-type dwarf novae based on newly obtained data and past publications. In many systems, the evolution superhump is found to be composed three distinct stages: an early evolutionary stage with a longer period, middle varying periods, final shorter, stable period. During stage, systems periods less than 0.08 d show positive derivatives. present observational characteristics these stages give greatly improved...
Abstract Continued from Kato et al. (2009, PASJ, 61, S395), we collected the times of superhump maxima for 68 SU UMa-type dwarf novae, mainly observed during 2009–2010 season. The newly obtained data confirmed basic findings reported in (ibid.): presence stages A–C and predominance positive period derivatives stage B systems with periods shorter than 0.07 d. There was a systematic difference longer 0.075 d between this study (ibid.). We suggest that possibly caused by relative lack...
Let G be a connected reductive group.The late Ramanathan gave notion of (semi)stable principal G-bundle on Riemann surface and constructed projective moduli space such objects.We generalize Ramanathan's construction to higher dimension, allowing also objects which we call semistable G-sheaves, in order obtain space: G-sheaf variety X is triple (P, E, ψ), where E torsion free sheaf X, P the open set U locally ψ an isomorphism between E| vector bundle associated by adjoint representation.We...
Let X be a smooth projective variety over C. We find the natural notion of semistable orthogonal bundle and construct moduli space, which we compactify by considering also sheaves, i.e. pairs (E,ϕ), where E is torsion free sheaf on ϕis symmetric nondegenerate (in open set locally free) bilinear form E. consider special adding trivialization ψof determinant such that det(ϕ)=ψ^2 ; symplectic skewsymmetric. More generally, tensors, multilinear forms sheaf, their space using GIT.
Let X be an irreducible smooth complex projective curve of genus g ≥ 4. Fix a line bundle L on X. M Sp (L) the moduli space semistable symplectic bundles (E, φ : E ⊗ → L) X, with form taking values in L. We show that automorphism group is generated by automorphisms ↦ M, where [Formula: see text], together induced
We present an analysis of photometric observations the eclipsing novalike variable DW UMa made by CBA consortium between 1999 and 2015. Analysis 372 new 260 previously published eclipse timings reveals a 13.6 yr period or quasi-period in times minimum light. The seasonal light curves show complex spectrum periodic signals: both positive negative 'superhumps', likely arising from prograde apsidal precession retrograde nodal accretion disc. These signals appear most prominently famously as...
In this highly speculative note we conjecture that it may be possible to understand features of coincident D-branes, such as the appearance enhanced non-abelian gauge symmetry, in a purely geometric fashion, using form geometry known scheme theory. We give very brief introduction some relevant ideas from theory, and point out how these work special cases.
We construct a Hecke correspondence for moduli space of symplectic vector bundles over curve. As an application we prove the following. Let X be complex smooth projective curve genus g(X) > 2 and L line bundle X. [Formula: see text] parametrizing stable pairs form (E,φ), where E is rank 2n φ : ⊗ → skew-symmetric nondegenerate bilinear on fibers E. If deg (E) ≥ 4n(g(X)-1), then there projectivized Picard text], which whose fiber any point ℙ(H 0 (X,E)). that this stable.
Abstract In this article we extend the proof given by Biswas and Gómez [Quart. J. Math. 54: 159–169, 2003] of a Torelli theorem for moduli space Higgs bundles with fixed determinant, to parabolic situation.
The eruption of the recurrent nova U Scorpii on 2010 January 28 is now all-time best observed event. We report 36,776 magnitudes throughout its 67 day eruption, for an average one measure every 2.6 minutes. This unique and unprecedented coverage first time that a has had any substantial amount fast photometry. With this, two new phenomena have been discovered: flares in early light curve seen from days 9–15 (which no proposed explanation) optical dips out eclipse 41–61 (likely caused by...
Let X be a non‐singular algebraic curve of genus g ⩾ 2, n 2 an integer, ξ line bundle over degree d > ( − 1) with , ) = 1 and M the moduli space stable bundles rank determinant . It is proved that Picard W respect to unique polarisation 2000 Mathematics Subject Classification 14H60, 14J60.
Fix integers $g\geq 3$ and $r\geq 2$, with if $g=3$. Given a compact connected Riemann surface $X$ of genus $g$, let $\MDH(X)$ denote the corresponding $\text{SL}(r, {\mathbb C})$ Deligne--Hitchin moduli space. We prove that complex analytic space determines (up to an isomorphism) unordered pair $\{X, \overline{X}\}$, where $\overline{X}$ is defined by opposite almost structure on $X$.