On fixed points of generalized linear-fractional transformations
Izvestiya. Mathematics , Tome 9 (1975) no. 5, pp. 1069-1079.

Voir la notice de l'article provenant de la source Math-Net.Ru

We study the fixed points of the generalized linear-fractional transformation $F_A$, induced by the plus-operator $A$, of the operator unit ball $\mathscr K_+$ into $\mathscr K_+$. In particular, for a linear-fractional transformation $F_A$ which maps $\mathscr K_+$ into its interior $\mathscr K_+^0$ we prove that if $F_A$ has a fixed point then the latter is unique. If, on the other hand, $F_A$ maps $\mathscr K_+$ onto $\mathscr K_+$, then, provided $F_A$ has a fixed point in $\mathscr K_+^0$, the following alternative is valid: 1) either this is the only fixed point of $F_A$ in $\mathscr K_+$, 2) or $F_A$ has a continuum of fixed points in the interior of $\mathscr K_+$ and at least two fixed points on the boundary $S_+$ of $\mathscr K_+$. In the intermediate case where $F_A(\mathscr K_+)\ne\mathscr K_+$ but $F_A(\mathscr K_+)\cap S_+\ne\varnothing$ we give an example of a linear-fractional transformation $F_A$ that has two fixed points: one in $\mathscr K_+^0$ and one on $S_+$. Bibliography: 11 titles.
@article{IM2_1975_9_5_a6,
     author = {V. A. Khatskevich},
     title = {On fixed points of generalized linear-fractional transformations},
     journal = {Izvestiya. Mathematics },
     pages = {1069--1079},
     publisher = {mathdoc},
     volume = {9},
     number = {5},
     year = {1975},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1975_9_5_a6/}
}
TY  - JOUR
AU  - V. A. Khatskevich
TI  - On fixed points of generalized linear-fractional transformations
JO  - Izvestiya. Mathematics 
PY  - 1975
SP  - 1069
EP  - 1079
VL  - 9
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM2_1975_9_5_a6/
LA  - en
ID  - IM2_1975_9_5_a6
ER  - 
%0 Journal Article
%A V. A. Khatskevich
%T On fixed points of generalized linear-fractional transformations
%J Izvestiya. Mathematics 
%D 1975
%P 1069-1079
%V 9
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM2_1975_9_5_a6/
%G en
%F IM2_1975_9_5_a6
V. A. Khatskevich. On fixed points of generalized linear-fractional transformations. Izvestiya. Mathematics , Tome 9 (1975) no. 5, pp. 1069-1079. http://geodesic.mathdoc.fr/item/IM2_1975_9_5_a6/

[1] Krein M. G., “Ob odnom novom primenenii printsipa nepodvizhnoi tochki v teorii operatorov v prostranstvakh s indefinitnoi metrikoi”, Dokl. AN SSSR, 1954, no. 5, 1023–1026 | MR

[2] Larionov E. A., “O chisle nepodvizhnykh tochek drobno-lineinogo preobrazovaniya operatornogo shara na sebya”, Matem. sb., 78(120):2 (1969), 202–213 | MR | Zbl

[3] Helton J. W., “Unitary operators on a space with an indefinite inner product”, J. of Funct. Anal., 6 (1970), 412–440 | DOI | MR | Zbl

[4] Helton I. W., “Operators unitary in indefinite metric and linear fractional transformations”, Acta Szeged, 32:3,4 | Zbl

[5] Krein M. G., Shmulyan Yu. L., “O drobno-lineinykh preobrazovaniyakh s operatornymi koeffitsientami”, Matem. issled., 2, no. 3(5), Kishinev, 1967, 64–96 | MR | Zbl

[6] Azizov T. Ya., Senderov V. A., “O nepreryvnosti nekotorykh klassov operatorov v normirovannykh prostranstvakh s indefinitnoi metrikoi”, Sb. trudov aspir. matem. f-ta, t. 2, Voronezh, 1971, 1–6 | MR | Zbl

[7] Langer G. K., “Zamechanie ob invariantnykh podprostranstvakh lineinykh operatorov v banakhovykh prostranstvakh s indefinitnoi metrikoi”, Matem. issled., 4, no. 1, Kishinev, 1969, 27–33 | MR

[8] Khatskevich V. A., “O plyus-operatorakh v normirovannykh prostranstvakh s indefinitnoi metrikoi”, Uspekhi matem. nauk, 27:5(167) (1972), 255–256 | MR | Zbl

[9] Iokhvidov I. S., “Ob odnoi lemme K. Fana, obobschayuschei printsip nepodvizhnoi tochki A. N. Tikhonova”, Dokl. AN SSSR, 159:3 (1964), 501–504 | Zbl

[10] Ginzburg Yu. P., Iokhvidov I. S., “Issledovaniya po geometrii beskonechnomernykh prostranstv s bilineinoi metrikoi”, Uspekhi matem. nauk, 17:4(106) (1962), 3–56 | MR

[11] Krein M. G., Shmulyan Yu. L., “O plyus-operatorakh v prostranstve s indefinitnoi metrikoi”, Matem. issled., 1, no. 1, Kishinev, 1966, 131–161 | MR | Zbl