In the first part of the paper we construct a ring structure on the rational cobordism classes of Morin maps (ie smooth generic maps of corank 1). We show that associating to a Morin map its Σ1r (or Ar) singular strata defines a ring homomorphism to Ω∗⊗ ℚ, the rational oriented cobordism ring. This is proved by analyzing the multiple-point sets of a product immersion. Using these homomorphisms we compute the ring of Morin maps.
In the second part of the paper we give a new method to find the oriented Thom polynomial of the Σ2 singularity type with ℚ coefficients. Then we provide a product formula for the Σ2 singularity in ℚ and the Σ1,1 singularity in ℤ2 coefficients.
Lippner, Gábor  1 ; Szűcs, András  2
@article{10_2140_agt_2010_10_1437,
author = {Lippner, G\'abor and Sz\'{u}cs, Andr\'as},
title = {Multiplicative properties of {Morin} maps},
journal = {Algebraic and Geometric Topology},
pages = {1437--1454},
year = {2010},
volume = {10},
number = {3},
doi = {10.2140/agt.2010.10.1437},
url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2010.10.1437/}
}
TY - JOUR AU - Lippner, Gábor AU - Szűcs, András TI - Multiplicative properties of Morin maps JO - Algebraic and Geometric Topology PY - 2010 SP - 1437 EP - 1454 VL - 10 IS - 3 UR - http://geodesic.mathdoc.fr/articles/10.2140/agt.2010.10.1437/ DO - 10.2140/agt.2010.10.1437 ID - 10_2140_agt_2010_10_1437 ER -
Lippner, Gábor; Szűcs, András. Multiplicative properties of Morin maps. Algebraic and Geometric Topology, Tome 10 (2010) no. 3, pp. 1437-1454. doi: 10.2140/agt.2010.10.1437
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