Zero-capital nonnegative wealth under a local deflator

ID: zero-capital-nonnegative-wealth-under-a-local-deflator

For a self-financing portfolio whose product with a strictly positive local deflator is a local martingale, nonnegative wealth makes that product a supermartingale. Starting from zero forces it to vanish almost surely at each time. Continuous paths then give simultaneous vanishing at every time on one probability-one event.

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