Quantitative analysis of metastability in reversible diffusion processes via a Witten complex approach.
Journées équations aux dérivées partielles (2004), article no. 8, 17 p.

We present here a simplified version of recent results obtained with B. Helffer and M. Klein. They are concerned with the exponentally small eigenvalues of the Witten Laplacian on 0-forms. We show how the Witten complex structure is better taken into account by working with singular values. This provides a convenient framework to derive accurate approximations of the first eigenvalues of Δ f,h (0) and solves efficiently the question of weakly resonant wells.

@article{JEDP_2004____A8_0,
     author = {Nier, Francis},
     title = {Quantitative analysis of metastability in reversible diffusion processes via a Witten complex approach.},
     journal = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     publisher = {Groupement de recherche 2434 du CNRS},
     year = {2004},
     doi = {10.5802/jedp.8},
     zbl = {1067.35057},
     mrnumber = {2135363},
     language = {en},
     url = {http://www.numdam.org/item/JEDP_2004____A8_0}
}
Nier, Francis. Quantitative analysis of metastability in reversible diffusion processes via a Witten complex approach.. Journées équations aux dérivées partielles (2004), article  no. 8, 17 p. doi : 10.5802/jedp.8. http://www.numdam.org/item/JEDP_2004____A8_0/

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