@article {Kosta2005,
 author="N. Mramor Kosta",
 title={A strong excision theorem for generalised Tate cohomology},
 journal="Bull. Austral. Math. Soc.",
 fjournal={Bulletin of the Australian Mathematical Society},
 volume="72",
 year="2005",
 number="1",
 pages="7--15",
 issn="0004-9727",
 coden="ALNBAB",
 language="English",
 date="13th January, 2005",
 classmath="57Q91, 57S99",
 publisher={AMPAI, Australian Mathematical Society},
 MRnumber="MR2162289",
 ZBLnumber="02212181",
 url="http://www.austms.org.au/Publ/Bulletin/V72P1/721-5017-Kosta/index.shtml",
 acknowledgement={Supported in part by the Ministry for Education, Science and Sport of the Republic of Slovenia Research Program No. 101-509. },
 abstract={ We consider the analogue of the fixed point theorem of A. Borel in the context of Tate cohomology. We show that for general compact Lie groups $G$ the Tate cohomology of a $G$-CW complex $X$ with coefficients in a field of characteristic $0$ is in general not isomorphic to the cohomology of the fixed point set, and thus the fixed point theorem does not apply. Instead, the following excision theorem is valid: if $X'$ is the subcomplex of all $G$-cells of orbit type $G/H$ where $\dim H>0$, and $V$ is a ring such that for every finite isotropy group $H$ the order $|H|$ is invertible in $V$, then $\widehat {H}^*_G(X;V)\cong \widehat {H}^*_G(X';V)$. In the special cases $G=\TT $, the circle group, and $G=\UU $, the group of unit quaternions, a more elementary geometric proof, using a cellular model of $\widehat {H}^*_\UU $ is given. }
}