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arXiv · 1405.5179

The Łojasiewicz Exponent of Semiquasihomogeneous Singularities

Abstract

Let $f: (\mathbb{C}^n,0) \rightarrow (\mathbb{C},0)$ be a semiquasihomogeneous function. We give a formula for the local Łojasiewicz exponent $\mathcal{L}_{0}(f)$ of $f$, in terms of weights of $f$. In particular, in the case of a quasihomogeneous isolated singularity $f$, we generalize a formula for $\mathcal{L}_{0}(f)$ of Krasiński, Oleksik and Płoski ([KOP09]) from $3$ to $n$ dimensions. This was previously announced in [TYZ10], but as a matter of fact it has not been proved correctly there, as noticed by the AMS reviewer T. Krasiński. As a consequence of our result, we get that the Łojasiewicz exponent is invariant in topologically trivial families of singularities coming from a quasihomogeneous germ. This is an affirmative partial answer to Teissier's conjecture. References [KOP09] Tadeusz Krasiński, Grzegorz Oleksik and Arkadiusz Płoski. The Łojasiewicz exponent of an isolated weighted homogeneous surface singularity. Proc. Amer. Math. Soc., 137(10):3387-3397, 2009. [TYZ10] Shengli Tan, Stephen S.-T. Yau and Huaiqing Zuo. Łojasiewicz inequality for weighted homogeneous polynomial with isolated singularity. Proc. Amer. Math. Soc., 138(11):3975-3984, 2010.

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Szymon Brzostowski. 2014-05-20. The Łojasiewicz Exponent of Semiquasihomogeneous Singularities. https://arxiv.org/abs/1405.5179

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