Geodesic
About numerical range of semigroup's generator
Izvestiya of Saratov University. Mathematics. Mechanics. Informatics, Tome 12 (2012) no. 1, pp. 29-32 
M. Yu. Romanova. About numerical range of semigroup's generator. Izvestiya of Saratov University. Mathematics. Mechanics. Informatics, Tome 12 (2012) no. 1, pp. 29-32. http://geodesic.mathdoc.fr/item/ISU_2012_12_1_a4/
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Voir la notice de l'article provenant de la source Math-Net.Ru

In the article the semigroup is built. The numerical range of its generator covers complex plane. It is provided that such semigroup is bounded.

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