Results 1 to 10 of about 55,344 (171)
A Lefschetz fixed point theorem in gravitational lensing [PDF]
Journal of Mathematical Physics, 2007 Topological invariants play an important r\^{o}le in the theory of gravitational lensing by constraining the image number. Furthermore, it is known that, for certain lens models, the image magnifications $\mu_i$ obey invariants of the form $\sum_i \mu_i ...
Marcus C. Werner
core +8 more sources
Lefschetz fixed point theorem for digital images [PDF]
Fixed Point Theory and Applications, 2013 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Özgür Ege, İsmet Karaca
semanticscholar +7 more sources
The Lefschetz Fixed Point Theorem for Compact Groups [PDF]
Proceedings of the American Mathematical Society, 1977 It is shown that every compact group G is a Q-simplicial space where Q is any field of characteristic zero. As a consequence it follows that G satisfies a variation of the Lefschetz fixed point theorem. It has been known for some time that the Lefschetz fixed point theorem applies to a few spaces other than just ANR spaces, especially if some care is ...
R. J. Knill
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A Lefschetz fixed point theorem for multivalued maps of finite spaces [PDF]
Mathematische Zeitschrift, 2019 We prove a version of the Lefschetz fixed point theorem for multivalued maps $F:X\multimap X$ in which $X$ is a finite $T_0$ space.
Jonathan Ariel Barmak +2 more
semanticscholar +9 more sources
A generalization of the Lefschetz fixed point theorem and detection of chaos [PDF]
Proceedings of the American Mathematical Society, 1999 We consider the problem of existence of fixed points of a continuous map f : X → X f:X\to X in (possibly) noninvariant subsets. A pair ( C , E ) (C,E) of subsets of X X induces a map f †
Roman Srzednicki
semanticscholar +4 more sources
On the Lefschetz Fixed Point Theorem [PDF]
, 2005 The abstract version of the Lefschetz fixed point theorem is proved which states the following: If \(X\) is a metric space and if \(X_0\subset X\) is such that \(X_0\) absorbs compact sets, \(f\:X\to X\) is a continuous map, \(f(X_0) \subset X_0\) and \(f/X_0\) is a Lefschetz map, then \(f\) is also (on \(X\)) a Lefschetz map. Here a continuous map \(f\
Lech Górniewicz
semanticscholar +6 more sources
A generalized Lefschetz fixed point theorem and symbolic dynamics in delay equations
Ergodic Theory and Dynamical Systems, 2002 We prove a generalized version of the Lefschetz fixed point theorem, and use it to obtain a variety of periodic and aperiodic solutions for differential delay equations; in particular, of the type \dot x(t) = f(x(t-1)). Here f:\mathbb R \to \mathbb R is odd and two-periodic, and we obtain both strictly periodic solutions and solutions periodic modulo a
Bernhard Lani‐Wayda, Roman Srzednicki
semanticscholar +4 more sources
The Lefschetz Fixed Point Theorem for Noncompact Locally Connected Spaces [PDF]
Transactions of the American Mathematical Society, 1972 Leray's notion of convexoid space is localized and used to show that if f: M- M is a relatively compact map on a locally convex manifold M, and f has no fixed points then its Lefschetz trace is zero. A similar theorem holds for certain ad junction spaces Y Uj Z where Y is Q-simplicial and Z is locally convexoid.
R. J. Knill
semanticscholar +5 more sources
Lefschetz fixed point theorem for acyclic maps with multiplicity
Topological Methods in Nonlinear Analysis, 2002 The authors study so-called weighted set-valued maps (in their terminology called \(m\)-multivalued maps), i.e. compact-valued upper semicontinuous mappings \(F: X\to Y\) between compact spaces whose values are finite disjoint unions of finitely many components, acyclic with respect to the Čech homology with coefficients in a field \(\mathbb{F}\) and ...
Fritz von Haeseler +2 more
semanticscholar +7 more sources
A NOTE ON THE LEFSCHETZ FIXED POINT THEOREM FOR ADMISSIBLE SPACES [PDF]
Bulletin of the Korean Mathematical Society, 2005 A Hausdorff topological space \(X\) is said to be a \textit{Lefschetz space} provided that, for any compact continuous map \(f: X\to X\), the generalized Lefschetz number \(\Lambda(f)\) is defined and \(\Lambda(f)\neq 0\) implies that \(f\) has a fixed point. By \textit{G. Fournier} and \textit{A. Granas} [J. Math. Pures Appl., IX. Sér.
Ravi P. Agarwal, Donal O’Regan
semanticscholar +3 more sources