Counting zeros of C-1 Fredholm maps of index 1

The degree defined by P. Benevieri and M. Furi (see 'A simple notion of orientability for Fredholm maps of index zero between Banach manifolds and degree theory', Ann. Sci. Math. Québec 22 (1998) 131-148) is used here to obtain some sharp lower bounds for the number of solutions of the λ-s...

Full description

Bibliographic Details
Main Authors: Lopez-Gomez, J, Mora-Corral, C
Format: Journal article
Language:English
Published: 2005
_version_ 1797074252120195072
author Lopez-Gomez, J
Mora-Corral, C
author_facet Lopez-Gomez, J
Mora-Corral, C
author_sort Lopez-Gomez, J
collection OXFORD
description The degree defined by P. Benevieri and M. Furi (see 'A simple notion of orientability for Fredholm maps of index zero between Banach manifolds and degree theory', Ann. Sci. Math. Québec 22 (1998) 131-148) is used here to obtain some sharp lower bounds for the number of solutions of the λ-sections of the compact components of the set of non-trivial solutions of ℑ(λ, x) =0, where ℑ is a C1 Fredholm map of index 1 such that ℑ(λ,0)= 0 for all λ ∈ ℝ. These bounds are given in terms of the parity of the linearized Fredholm family D 2ℑ(·,0). The parity is a local invariant measuring the change of the orientation of D2ℑ (λ,0) as λ crosses an interval. The set of eigenvalues of D2ℑ(·,0) is not assumed to be discrete. Therefore, even in the classical situation when ℑ is a compact perturbation of the identity, the results presented here are completely new. © 2005 London Mathematical Society.
first_indexed 2024-03-06T23:33:27Z
format Journal article
id oxford-uuid:6cd4e524-2043-4267-8eea-ccfa64fc9bf8
institution University of Oxford
language English
last_indexed 2024-03-06T23:33:27Z
publishDate 2005
record_format dspace
spelling oxford-uuid:6cd4e524-2043-4267-8eea-ccfa64fc9bf82022-03-26T19:13:45ZCounting zeros of C-1 Fredholm maps of index 1Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:6cd4e524-2043-4267-8eea-ccfa64fc9bf8EnglishSymplectic Elements at Oxford2005Lopez-Gomez, JMora-Corral, CThe degree defined by P. Benevieri and M. Furi (see 'A simple notion of orientability for Fredholm maps of index zero between Banach manifolds and degree theory', Ann. Sci. Math. Québec 22 (1998) 131-148) is used here to obtain some sharp lower bounds for the number of solutions of the λ-sections of the compact components of the set of non-trivial solutions of ℑ(λ, x) =0, where ℑ is a C1 Fredholm map of index 1 such that ℑ(λ,0)= 0 for all λ ∈ ℝ. These bounds are given in terms of the parity of the linearized Fredholm family D 2ℑ(·,0). The parity is a local invariant measuring the change of the orientation of D2ℑ (λ,0) as λ crosses an interval. The set of eigenvalues of D2ℑ(·,0) is not assumed to be discrete. Therefore, even in the classical situation when ℑ is a compact perturbation of the identity, the results presented here are completely new. © 2005 London Mathematical Society.
spellingShingle Lopez-Gomez, J
Mora-Corral, C
Counting zeros of C-1 Fredholm maps of index 1
title Counting zeros of C-1 Fredholm maps of index 1
title_full Counting zeros of C-1 Fredholm maps of index 1
title_fullStr Counting zeros of C-1 Fredholm maps of index 1
title_full_unstemmed Counting zeros of C-1 Fredholm maps of index 1
title_short Counting zeros of C-1 Fredholm maps of index 1
title_sort counting zeros of c 1 fredholm maps of index 1
work_keys_str_mv AT lopezgomezj countingzerosofc1fredholmmapsofindex1
AT moracorralc countingzerosofc1fredholmmapsofindex1