Let $\{T(t):t>0\}$ be a strongly continuous semigroup of linear contractions in $L_p$, $1
0$ a positive linear contraction $P(t)$ in $L_p$ such that $|T(t)f|\leq P(t)|f|$ for all $f\in L_p$, then there exists a strongly continuous semigroup $\{S(t):t>0\}$ of positive linear contractions in $L_p$ such that $|T(t)f|\leq S(t)|f|$ for all $t>0$ and $f\in L_p$. Using this and Akcoglu's dominated ergodic theorem for positive linear contractions in $L_p$, we also prove multiparameter pointwise ergodic and local ergodic theorems for such semigroups.
@article{118672, author = {Ryotaro Sato}, title = {Ergodic properties of contraction semigroups in $L\_p$, $1<p<\infty$}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {35}, year = {1994}, pages = {337-346}, zbl = {0814.47010}, mrnumber = {1286580}, language = {en}, url = {http://dml.mathdoc.fr/item/118672} }
Sato, Ryotaro. Ergodic properties of contraction semigroups in $L_p$, $1
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