A Proof That Thompson’s Groups Have Infinitely Many Relative Ends
نویسنده
چکیده
We show that each of Thompson’s groups F , T , and V has infinitely many ends relative to the groups F[0,1/2], T[0,1/2], and V[0,1/2) (respectively). As an application, we simplify the proof, due to Napier and Ramachandran, that F , T , and V are not Kähler groups. We go on to show that Thompson’s groups T and V have Serre’s property FA. The main theorems together answer a question on Bestvina’s problem list that was originally posed by Mohan Ramachandran.
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