On Spectral Properties of the <i>L</i> Operator in the Lax Pair of the sine-Gordon Equation

We analyze the periodic spectrum of the L operator in the Lax pair of the sine-Gordon equation in terms of the regularity of the potential.

Mathematics Subject Classification 2000: 37K10, 35Q55.
Key words: sine-Gordon equation, sinh-Gordon equation, Lax pair, decay properties of gap lengths.

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On Spectral Properties of the L Operator in the Lax Pair of the sine-Gordon Equation