Semi-stable model and Neron model for family of elliptic curves - MathOverflow most recent 30 from http://mathoverflow.net2013-05-22T11:40:24Zhttp://mathoverflow.net/feeds/question/25018http://www.creativecommons.org/licenses/by-nc/2.5/rdfhttp://mathoverflow.net/questions/25018/semi-stable-model-and-neron-model-for-family-of-elliptic-curvesSemi-stable model and Neron model for family of elliptic curvesNew_to_MO2010-05-17T15:20:42Z2010-05-17T15:34:42Z
<p>I am looking for an "easy-to-understand" reference for Neron Models. Specifically if I have a semi-stable family of elliptic curves over $Spec {O}_K$ , with generic fibre $E_K$ and special fibre $E_k$ , then $E_k$ is an $N$-gon of $\mathbb{P}^1$'s. In this context, what is the Neron model of $E_K$? I guess what I am asking is for a geometric description of the special fibre of the Neron model for $E_K$.</p>
http://mathoverflow.net/questions/25018/semi-stable-model-and-neron-model-for-family-of-elliptic-curves/25022#25022Answer by Pete L. Clark for Semi-stable model and Neron model for family of elliptic curvesPete L. Clark2010-05-17T15:29:07Z2010-05-17T15:34:42Z<p>The place to look for this is Chapter 4 ("The Neron Model") of Silverman's book <em>Advanced Topics in the Arithmetic of Elliptic Curves</em>, specifically Theorem 4.6.1: the Neron model of an elliptic curve is obtained by removing the singular points from the minimal regular proper model.</p>
<p>Thus in your case the connected component is a rational curve with two points removed: as a group it is $\mathbb{G}_m$, the multiplicative group. The component group here is cyclic of order $N$. </p>