Zobrazeno 1 - 10
of 22
pro vyhledávání: '"FRANCISCO BRAUN"'
Autor:
FRANCISCO BRAUN, JAUME LLIBRE
Publikováno v:
Anais da Academia Brasileira de Ciências, Vol 87, Iss 3, Pp 1519-1524 (2015)
Let F= (f, g) : R2 → R2be a polynomial map such that det DF(x) is different from zero for all x∈ R2. We assume that the degrees of fand gare equal. We denote by the homogeneous part of higher degree of f and g, respectively. In this note we provi
Externí odkaz:
https://doaj.org/article/fa09d31c088b4fd79e96cc9a96da95bb
Publikováno v:
Anais da Academia Brasileira de Ciências, Vol 90, Iss 3, Pp 2599-2616
Abstract In this paper we describe the global phase portrait of the Hamiltonian system associated to a Pinchuk map in the Poincaré disc. In particular, we prove that this phase portrait has 15 separatrices, five of them singular points, and 7 canoni
Externí odkaz:
https://doaj.org/article/b3c8078e1ed942ef94b1ceee21f4aca1
Publikováno v:
Proceedings of the American Mathematical Society. 150:1795-1798
We construct a non-injective analytic local diffeomorphism of R 3 \mathbb {R}^3 such that the pre-image of every affine hyperplane is connected. This disproves a conjecture proposed by S. Nollet and F. Xavier in 2002.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::25c4fda51cf0e1e40cc992c231248b64
https://doi.org/10.1090/proc/14779
https://doi.org/10.1090/proc/14779
Autor:
Francisco Braun, Claudia Valls
Publikováno v:
Proceedings of the Edinburgh Mathematical Society. 64:1028-1036
It is known that a polynomial local diffeomorphism $(f,\, g): {\mathbb {R}}^{2} \to {\mathbb {R}}^{2}$ is a global diffeomorphism provided the higher homogeneous terms of $f f_x+g g_x$ and $f f_y+g g_y$ do not have real linear factors in common. Here
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9d14e905af8a0a91019484091bab370d
https://doi.org/10.1017/s0013091521000766
https://doi.org/10.1017/s0013091521000766
Autor:
Francisco Braun, Filipe Fernandes
Publikováno v:
Journal of Pure and Applied Algebra. 227:107345
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a66888c9ea2aab84a5038e0763c8f95d
https://doi.org/10.1016/j.jpaa.2023.107345
https://doi.org/10.1016/j.jpaa.2023.107345
Publikováno v:
Proceedings of the Edinburgh Mathematical Society. 63:666-675
We obtain a new theorem for the non-properness set $S_f$ of a non-singular polynomial mapping $f:\mathbb C^n \to \mathbb C^n$. In particular, our result shows that if f is a counterexample to the Jacobian conjecture, then $S_f\cap Z \neq \emptyset $,
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::81eab5969f49df1b89df1346695675a8
https://doi.org/10.1017/s0013091520000061
https://doi.org/10.1017/s0013091520000061
Let $f, g: \mathbb{R}^2 \to \mathbb{R}$ be two submersion functions and $\mathscr{F}(f)$ and $\mathscr{F}(g)$ be the regular foliations of $\mathbb{R}^2$ whose leaves are the connected components of the levels sets of $f$ and $g$, respectively. The t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a94a02e6d229cdf1d2106ca5144d5f43
http://arxiv.org/abs/2203.01019
http://arxiv.org/abs/2203.01019
Autor:
Francisco Braun, Filipe Fernandes
Publikováno v:
Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual)
Universidade de São Paulo (USP)
instacron:USP
Universidade de São Paulo (USP)
instacron:USP
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cc6371ef5ff81f82b0d4e6411bd4083b
Autor:
Ana Cristina Mereu, Francisco Braun
Let the three-dimensional differential system defined by the jerk equation x = − a x + x x 2 − x 3 − b x + c x , with a , b , c ∈ R . When a = b = 0 and c 0 the equilibrium point localized at the origin of coordinates is a zero-Hopf equilibri
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a2444b01460688c64a3702bee2287ef1
http://arxiv.org/abs/2003.12280
http://arxiv.org/abs/2003.12280
Autor:
B. Oréfice-Okamoto, Francisco Braun
Publikováno v:
Journal of Mathematical Analysis and Applications. 443:688-706
We prove the following version of the real Jacobian conjecture: “Let F = ( p , q ) : R 2 → R 2 be a polynomial map with nowhere zero Jacobian determinant. If the degree of p is less than or equal to 4, then F is injective”. The approach to prov
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a02eb73d8ecfbf687bb3f1893813367b
https://doi.org/10.1016/j.jmaa.2016.05.048
https://doi.org/10.1016/j.jmaa.2016.05.048