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Schwinger variational principle and Padé approximants

✍ Scribed by C.R Garibotti

Publisher
Elsevier Science
Year
1972
Tongue
English
Weight
483 KB
Volume
71
Category
Article
ISSN
0003-4916

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✦ Synopsis

We show that any [N, M] Pade approximant to the nonrelativistic scattering amplitude is equivalent to solving the scattering equations in a particular fmite subspace. It follows that the Pad& approximants can be obtained by using appropriate trial functions in the Schwinger variational principle. The possible application of the stationarity principle to determine an optimal subspace is discussed.

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