Abstract
The embedded cobordism category under study in this paper generalizes the category of conformal surfaces, introduced by G. Segal in [S2] in order to formalize the concept of field theories. Our main result identifies the homotopy type of the classifying space of the embedded d-dimensional cobordism category for all d. For d = 2, our results lead to a new proof of the generalized Mumford conjecture, somewhat different in spirit from the original one, presented in [MW].
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S. Galatius was partially supported by NSF grant DMS-0505740 and the Clay Institute.
M. Weiss was partially supported by the Royal Society and the Mittag-Leffler Institute.
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Galatius, S., Madsen, I., Tillmann, U. et al. The homotopy type of the cobordism category. Acta Math 202, 195–239 (2009). https://doi.org/10.1007/s11511-009-0036-9
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DOI: https://doi.org/10.1007/s11511-009-0036-9