This paper analyzes a class of variational inequalities involving a double-phase degenerate parabolic operator with variable exponents, which arises in the valuation of American put options. By establishing energy estimates for the associated penalty problem and applying a limiting argument, the existence of a weak solution is obtained. The uniqueness of the weak solution is also discussed.
Citation: Qingjun Zhao. Existence and uniqueness of solutions to variational inequalities involving a double-phase degenerate parabolic operator with variable exponents arising from American put option valuation analysis[J]. Electronic Research Archive, 2026, 34(2): 1063-1078. doi: 10.3934/era.2026049
This paper analyzes a class of variational inequalities involving a double-phase degenerate parabolic operator with variable exponents, which arises in the valuation of American put options. By establishing energy estimates for the associated penalty problem and applying a limiting argument, the existence of a weak solution is obtained. The uniqueness of the weak solution is also discussed.
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