The Standard Finance Theory holds that investors are rational, and the security market is efficient due to the possibility of perfect arbitrage, even if most of the investors are irrational.

标准金融学认为，投资者是理性人，即使大部分投资者是非理性人，但是由于完美套利的存在，市场也将是有效市场。

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Its Nobel laureates had gone from the old long-short play into more sophisticated ventures, like finely tuned arbitrage the practice of buying the same security simultaneously in different markets to profit from minute spreads.

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