Manin–Drinfeld theorem
In mathematics, the Manin–Drinfeld theorem, proved by Manin (1972) and Drinfeld (1973), states that the difference of two cusps of a modular curve has finite order in the Jacobian variety.
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Wikipedia
In mathematics, the Manin–Drinfeld theorem, proved by Manin (1972) and Drinfeld (1973), states that the difference of two cusps of a modular curve has finite order in the Jacobian variety.