{ "id": "1603.08711", "version": "v1", "published": "2016-03-29T10:24:43.000Z", "updated": "2016-03-29T10:24:43.000Z", "title": "On twists of smooth plane curves", "authors": [ "Eslam Badr", "Francesc Bars", "Elisa Lorenzo" ], "categories": [ "math.NT", "math.AG" ], "abstract": "Given a smooth curve defined over a field $k$ that admits a non-singular plane model over $\\overline{k}$, a fixed separable closure of $k$, it does not necessarily have a non-singular plane model defined over the field $k$. We determine under which conditions this happens and we show an example of such phenomenon. Now, even assuming that such a smooth plane model exists, we wonder about the existence of non-singular plane models over $k$ for its twists. We characterize twists possessing such models and use such characterization to improve, for the particular case of smooth plane curves, the algorithm to compute twists of non-hyperelliptic curves wrote recently down by the third author. We also show an example of a twist not admitting such non-singular plane model. As a consequence, we get explicit equations for a non-trivial Brauer-Severi surface. Finally, we obtain a theoretical result to compute all the twists of smooth plane curves with cyclic automorphism group having a $k$-model whose automorphism group is generated by a diagonal matrix. Some examples are also provided.", "revisions": [ { "version": "v1", "updated": "2016-03-29T10:24:43.000Z" } ], "analyses": { "subjects": [ "11G30", "11D41", "14H37", "14H50", "14H45", "12F12" ], "keywords": [ "smooth plane curves", "non-singular plane model", "non-hyperelliptic curves wrote", "smooth plane model", "non-trivial brauer-severi surface" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2016arXiv160308711B" } } }