5 resultados para Grassmann manifold

em Universidade Complutense de Madrid


Relevância:

10.00% 10.00%

Publicador:

Resumo:

We investigate some topological properties, in particular formality, of compact Sasakian manifolds. Answering some questions raised by Boyer and Galicki, we prove that all higher (than three) Massey products on any compact Sasakian manifold vanish. Hence, higher Massey products do obstruct Sasakian structures. Using this, we produce a method of constructing simply connected K-contact non-Sasakian manifolds. On the other hand, for every n > 3, we exhibit the first examples of simply connected compact Sasakian manifolds of dimension 2n + 1 that are non-formal. They are non-formal because they have a non-zero triple Massey product. We also prove that arithmetic lattices in some simple Lie groups cannot be the fundamental group of a compact Sasakian manifold.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We propose and examine an integrable system of nonlinear equations that generalizes the nonlinear Schrodinger equation to 2 + 1 dimensions. This integrable system of equations is a promising starting point to elaborate more accurate models in nonlinear optics and molecular systems within the continuum limit. The Lax pair for the system is derived after applying the singular manifold method. We also present an iterative procedure to construct the solutions from a seed solution. Solutions with one-, two-, and three-lump solitons are thoroughly discussed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this paper, dedicated to Prof. Lou Kauffman, we determine the Thurston’s geometry possesed by any Seifert fibered conemanifold structure in a Seifert manifold with orbit space (Formula presented.) and no more than three exceptional fibers, whose singular set, composed by fibers, has at most three components which can include exceptional or general fibers (the total number of exceptional and singular fibers is less than or equal to three). We also give the method to obtain the holonomy of that structure. We apply these results to three families of Seifert manifolds, namely, spherical, Nil manifolds and manifolds obtained by Dehn surgery on a torus knot (Formula presented.). As a consequence we generalize to all torus knots the results obtained in [Geometric conemanifolds structures on (Formula presented.), the result of (Formula presented.) surgery in the left-handed trefoil knot (Formula presented.), J. Knot Theory Ramifications 24(12) (2015), Article ID: 1550057, 38pp., doi: 10.1142/S0218216515500571] for the case of the left handle trefoil knot. We associate a plot to each torus knot for the different geometries, in the spirit of Thurston.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this dissertation I will study the phenomenon of the hipérbole sacroprofana in different Castillian writers of the 15th to the 17th centuries, in order to show in what does this fact consists, and how it has to be sorted out. Thus, I will also show how this tendency unfolds and how the use of either one or another resource leads the hipérbole towards different expressive horizons. Although the hipérbole sacroprofana is usually detected by most of scholars, it has never met proper attention, so that it has turned into a jumble in which the most disparate instances of a lady’s praise. Yet, an accurate analysis of this phenomenon reveals that this is not the case, and that this resource has manifold aspects and varying intentions and expressive ways as well. In this dissertation, where some five thousand hipérboles are analysed, I point out the various kinds of instances, and I classify them according to their expression and their literary-intellectual interweaving. Besides I monitor this fact to explain how hipérbole varies with the passage of times. By so doing a deficiency in the history of literary criticism, which mistook and likened all sorts of hipérboles in poetical texts, is eased. So we can see that, in its origins, hipérbole was confined to using sacred terms in profane poems out of their context (which I call hipérbole léxica o de inserción terminológica). This resource was effectual insofar as the use of words religiously connoted carried along devout attitudes towards poems of earthly love so that the lady and the feeling that the author professed became “adulterated” by Christian attitudes...

Relevância:

10.00% 10.00%

Publicador:

Resumo:

It is a widely acknowledged and often unquestioned fact that patriarchy and its modes of behaviour and social organization favour the appearance of trauma on the weakest (and defenceless) members of society: women. In the last decades, trauma seems to have taken the baton of typically female maladies such as 19th c. hysteria or 20th c. madness. Feminists in the 20th c. have long worked to prove the connection between the latter affections (and their reflection in literary texts) and patriarchal oppression or expectations of feminine behaviour and accordance to roles and rules. With Trauma Studies on the rise, the approach to the idea of the untold as related to femininity is manifold: on the one hand, is not trauma, which precludes telling about one’s own experience and keeps it locked not only from the others, but also from ourselves, the ultimate secrecy? On the other hand, when analyzing works that reflect trauma, one is astounded by the high number of them with a female protagonist and an almost all-female cast: in this sense, a ‘feminist’ reading is almost compulsory, in the sense that it is usually the author’s assumption that patriarchal systems of exploitation and expectations favour traumatic events and their outcome (silence and secrets) on the powerless, usually women. Often, traumatic texts combine feminism with other analytical discourses (one of the topics proposed for this panel): Toni Morrison’s study of traumatic responses in The Bluest Eye and Beloved cannot be untangled from her critique of slavery; just as much of Chicana feminism and its representations of rape and abuse (two main agents of trauma) analyze the nexus of patriarchy, new forms of post-colonialism, and the dynamics of power and powerlessness in ethnic contexts. Within this tradition that establishes the secrecies of trauma as an almost exclusively feminine characteristic, one is however faced with texts which have traumatized males as protagonists: curiously enough, most of these characters have suffered trauma through a typically masculine experience: that of war and its aftermath. By analyzing novels dealing with war veterans from Vietnam or the Second World War, the astounding findings are the frequent mixture of masculine or even ‘macho’ values and the denial of any kind of ‘feminine’ characteristics, combined with a very strict set of rules of power and hierarchy that clearly establish who is empowered and who is powerless. It is our argument that this replication of patriarchal modes of domination, which place the lowest ranks of the army in a ‘feminine’ situation, blended with the compulsory ‘macho’ stance soldiers are forced to adopt as army men (as seen, for example, in Philip Caputo’s Indian Country, Larry Heinemann’s Paco’s Story or Ed Dodge’s DAU: A Novel of Vietnam) furthers the onset and seriousness of ulterior trauma. In this sense, we can also analyze this kind of writing from a ‘feminist’ point of view, since the dynamics of über-patriarchal power established at the front at war-time deny any display of elements traditionally viewed as ‘feminine’ (such as grief, guilt or emotions) in soldiers. If trauma is the result of a game of patriarchal empowerment, how can feminist works, not only theoretical, but also fictional, overthrow it? Are ‘feminine’ characteristics necessary to escape trauma, even in male victims? How can feminist readings of trauma enhance our understanding of its dynamics and help produce new modes of interaction that transcend power and gender division as the basis for the organization of society?