منابع مشابه
Kähler groups, quasi-projective groups and 3-manifold groups
We prove two results relating 3-manifold groups to fundamental groups occurring in complex geometry. Let N be a compact, connected, orientable 3-manifold. If N has non-empty, toroidal boundary, and π1(N) is a Kähler group, then N is the product of a torus with an interval. On the other hand, if N has either empty or toroidal boundary, and π1(N) is a quasi-projective group, then all the prime co...
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We formulate a new theorem giving several necessary and su‰cient conditions in order that a surjection of the fundamental group p1ðX Þ of a compact Kähler manifold onto the fundamental group Pg of a compact Riemann surface of genus gd 2 be induced by a holomorphic map. For instance, it su‰ces that the kernel be finitely generated. We derive as a corollary a restriction for a group G, fitting in...
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This is a contribution to the project of quiver approaches to quasi-quantum groups initiated in [13]. We classify Majid bimodules over groups with 3-cocycles by virtue of projective representations. This leads to a theoretic classification of graded pointed Majid algebras over path coalgebras, or equivalently cofree pointed coalgebras, and helps to provide a projective representation-theoretic ...
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Let $mathcal {A}$ be an abelian category with enough projective objects and $mathcal {X}$ be a full subcategory of $mathcal {A}$. We define Gorenstein projective objects with respect to $mathcal {X}$ and $mathcal{Y}_{mathcal{X}}$, respectively, where $mathcal{Y}_{mathcal{X}}$=${ Yin Ch(mathcal {A})| Y$ is acyclic and $Z_{n}Yinmathcal{X}}$. We point out that under certain hypotheses, these two G...
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The similarity between finite-dimensional projective spaces and finite abelian groups has often been noted(1); and thus one may expect that the more general features of these two theories are identical. But the likeness is more than a superficial one; and consequently it is possible to give a unified treatment for spaces and groups. It may be worthwhile to indicate in a few lines the developmen...
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ژورنال
عنوان ژورنال: Bulletin de la Société mathématique de France
سال: 1970
ISSN: 0037-9484,2102-622X
DOI: 10.24033/bsmf.1691