Central sequences in the factor associated with Thompson’s group F
Annales de l'Institut Fourier, Volume 48 (1998) no. 4, p. 1093-1106

We prove that the type II 1 factor L(F) generated by the regular representation of F is isomorphic to its tensor product with the hyperfinite type II 1 factor. This implies that the unitary group of L(F) is contractible with respect to the topology defined by the natural Hilbertian norm.

Nous montrons que le facteur L(F), de type II 1 engendré par la représentation régulière de F, est isomorphe à son produit tensoriel avec le facteur hyperfini de type II 1 . Cela implique que le groupe unitaire de L(F) est contractile par rapport à la topologie définie par la norme hilbertienne naturelle.

@article{AIF_1998__48_4_1093_0,
     author = {Jolissaint, Paul},
     title = {Central sequences in the factor associated with Thompson's group $F$},
     journal = {Annales de l'Institut Fourier},
     publisher = {Association des Annales de l'institut Fourier},
     volume = {48},
     number = {4},
     year = {1998},
     pages = {1093-1106},
     doi = {10.5802/aif.1650},
     zbl = {0915.46052},
     mrnumber = {2000b:46108},
     language = {en},
     url = {http://www.numdam.org/item/AIF_1998__48_4_1093_0}
}
Jolissaint, Paul. Central sequences in the factor associated with Thompson’s group $F$. Annales de l'Institut Fourier, Volume 48 (1998) no. 4, pp. 1093-1106. doi : 10.5802/aif.1650. http://www.numdam.org/item/AIF_1998__48_4_1093_0/

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