Divisors on real curves
نویسنده
چکیده
Let X be a smooth projective curve over R. In the first part, we study e¤ective divisors on X with totally real or totally complex support. We give some numerical conditions for a linear system to contain such a divisor. In the second part, we describe the special linear systems on a real hyperelliptic curve and prove a new Cli¤ord inequality for such curves. Finally, we study the existence of complete linear systems of small degrees and dimension r on a real curve. 2000 Mathematics Subject Classification. 14C20, 14H51, 14P25, 14P99
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