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4
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There is a characterization of Schwarzian derivatives of rational maps:
section 3 in the text:
http://www.math.purdue.edu/~eremenko/Pdf/schwarz.pdfhttp://www.math.purdue.edu/~eremenko/dvi/schwarz.pdf
There is something similar also in arXiv:math/0512370, chapter 2.
All these descriptions are various systems of algebraic equations.
One of them, the "Bethe ansatz equations for the Gaudin model",
proved to be very useful, see
Mukhin, Tarasov and Varchenko, The B. and M. Shapiro conjecture in real algebraic
geometry and the Bethe ansatz, Ann. Math. 170, 2 2009, 863-15.
There is some cell decomposition of the sphere which can be intrinsically related
to a ratonal function. It is described in the paper
Bonk, Eremenko, Schlicht regions of entire and meromorphic functions,
J. d'Analyse, 77, 1999, 69-104, Sections 7.8.
For a given cell decomposition, a rational function
can be recovered using an algorithm similar to Thurston's circle packing algorithm.
However, with this description, critical points or critical valued cannot
be prescribed, and the cell decomposition does not determine the rational function
completely.
Alex Eremenko.
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|
|
|
3
|
|
|
There is a characterization of Schwarzian derivatives of rational maps:
section 3 in the text:
http://www.math.purdue.edu/~eremenko/Pdf/schwarz.pdf
There is something similar also in arXiv:math/0512370, chapter 2.
All these descriptions are various systems of algebraic equations.
One of them, the "Bethe ansatz equations for the Gaudin model",
proved to be very useful, see
Mukhin, Tarasov and Varchenko, The B. and M. Shapiro conjecture in real algebraic
geometry and the Bethe ansatz, Ann. Math. 170, 2 2009, 863-15.
There is some cell decomposition of the sphere which can be intrinsically related
to a ratonal function. It is described in the paper
Bonk, Eremenko, Schlicht regions of entire and meromorphic functions,
J. d'Analyse, 77, 1999, 69-104, Sections 7.8.
For a given cell decomposition, the a rational function
can be recovered using an algorithm similar to Thurston's circle packing algorithm.
However, with this description, critical points or critical valued cannot
be prescribed, and the cell decomosition decomposition does not determine the rational function
completely.
Alex Eremenko.
|
|
|
|
2
|
|
|
There is a characterization of Schwarzian derivatives of rational maps:
section 3 in the text:
http://www.math.purdue.edu/~eremenko/Pdf/schwarz.pdf
There is something similar also in arXiv:math/0512370, chapter 2.
All these descriptions are various systems of algebraic equations.
One of them, the "Bethe ansatz equations for the Gaudin model",
proved to be very useful, see
Mukhin, Tarasov and Varchenko, The B. and M. Shapiro conjecture in real algebraic
geometry and the Bethe ansatz, Ann. Math. 170, 2 2009, 863-15.
There is some cell decomposition of the sphere which can be intrinsically related
to a ratonal function. It is described in the paper
Bonk, Eremenko, Schlicht regions of entire and meromorphic functions,
J. d'Analyse, 77, 1999, 69-104, Sections 7.8.
For a given cell decomposition, the rational function
can be recovered using an algorithm similar to Thurston's circle packing algorithm.
However, with this description, critical points or critical valued cannot
be prescribed: , and the cell decomosition itself already determines does not determine the rational functioncompletely.
Alex Eremenko.
|
|
|
|
1
|
|
|
There is a characterization of Schwarzian derivatives of rational maps:
section 3 in the text:
http://www.math.purdue.edu/~eremenko/Pdf/schwarz.pdf
There is something similar also in arXiv:math/0512370, chapter 2.
All these descriptions are various systems of algebraic equations.
One of them, the "Bethe ansatz equations for the Gaudin model",
proved to be very useful, see
Mukhin, Tarasov and Varchenko, The B. and M. Shapiro conjecture in real algebraic
geometry and the Bethe ansatz, Ann. Math. 170, 2 2009, 863-15.
There is some cell decomposition of the sphere which can be intrinsically related
to a ratonal function. It is described in the paper
Bonk, Eremenko, Schlicht regions of entire and meromorphic functions,
J. d'Analyse, 77, 1999, 69-104, Sections 7.8.
For a given cell decomposition, the rational function
can be recovered using an algorithm similar to Thurston's circle packing algorithm.
However, with this description, critical points or critical valued cannot
be prescribed: the cell decomosition itself already determines the rational function
completely.
Alex Eremenko.
|
|
|