• Nguyen Xuan Viet Nhan Basque Center for Applied Mathematics, Bilbao, Spain,



Bi-Lipschitz contact invariant, Rank, Thom-Boardman symbol.


We address the question of whether the Thom-Boardman symbol of a map germ is an invariant with respect to bi-Lipschitz right equivalence. We give a counterexample showing that in general the answer is negative. We prove that the rank of a map germ is a bi-Lipschitz contact invariant. Consequently, the first Thom-Boardman symbol and its length are bi-Lipschitz contact invariants.


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Volume and Issues


Natural Sciences and Technology

How to Cite

Nguyen, X. V. N. (2022). BI-LIPSCHITZ CONTACT INVARIANCE OF RANK. Dalat University Journal of Science, 12(2), 40-47.

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