Some model theory of ${\rm SL}(2,{\mathbb R})$
Fundamenta Mathematicae, Tome 229 (2015) no. 2, pp. 117-128
Cet article a éte moissonné depuis la source Institute of Mathematics Polish Academy of Sciences
We study the action of $G = {\rm SL} (2,\mathbb R)$, viewed as a group definable in the structure $M = (\mathbb R,+,\times )$, on its type space $S_{G}(M)$. We identify a minimal closed $G$-flow $I$ and an idempotent $r\in I$ (with respect to the Ellis semigroup structure $*$ on $S_{G}(M)$). We also show that the “Ellis group” $(r*I,*)$ is nontrivial, in fact it is the group with two elements, yielding a negative answer to a question of Newelski.
Keywords:
study action mathbb viewed group definable structure mathbb times its type space identify minimal closed g flow idempotent respect ellis semigroup structure * ellis group r*i * nontrivial group elements yielding negative answer question newelski
Affiliations des auteurs :
Jakub Gismatullin 1 ; Davide Penazzi 2 ; Anand Pillay 3
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author = {Jakub Gismatullin and Davide Penazzi and Anand Pillay},
title = {Some model theory of ${\rm SL}(2,{\mathbb R})$},
journal = {Fundamenta Mathematicae},
pages = {117--128},
year = {2015},
volume = {229},
number = {2},
doi = {10.4064/fm229-2-2},
language = {en},
url = {http://geodesic.mathdoc.fr/articles/10.4064/fm229-2-2/}
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TY - JOUR
AU - Jakub Gismatullin
AU - Davide Penazzi
AU - Anand Pillay
TI - Some model theory of ${\rm SL}(2,{\mathbb R})$
JO - Fundamenta Mathematicae
PY - 2015
SP - 117
EP - 128
VL - 229
IS - 2
UR - http://geodesic.mathdoc.fr/articles/10.4064/fm229-2-2/
DO - 10.4064/fm229-2-2
LA - en
ID - 10_4064_fm229_2_2
ER -
Jakub Gismatullin; Davide Penazzi; Anand Pillay. Some model theory of ${\rm SL}(2,{\mathbb R})$. Fundamenta Mathematicae, Tome 229 (2015) no. 2, pp. 117-128. doi: 10.4064/fm229-2-2
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