A polymer includes a repeating unit shown by a general formula (1). R1 represents a hydrogen atom, a methyl group, a fluorine atom, or a trifluoromethyl group. R2 represents a substituted or unsubstituted aryl group having 6 to 22 carbon atoms. Y represents a carbon atom. X represents —X1Z1X2— which is an atomic group which forms a cyclic structure including a heteroatom together with Y. Z1 represents —O—, —S—, —CO—, —COO—, —SO—, or —SO2—. Each of X1 and X2 individually represents a single bond, a methylene group, or an alkylene group having 2 to 25 carbon atoms. Each of X1 and X2 is unsubstituted or substituted with a substituent, and optionally a carbon atom included in X1 and a carbon atom included in X2 are bonded via a divalent group.