标题： 经济的（不幸的）复杂性 显示英文标题

标题： The (unfortunate) complexity of the economy

摘要： 这篇文章是对一篇发表在《自然》455, 1181 (2008) [arXiv:0810.5306]上的短文的后续。越来越清楚的是，市场的不稳定动态主要是内生的，而不是由于对外部新闻的理性处理。我详细阐述了这样的观点：自旋玻璃类型的問題，其中競爭和多樣性的結合通常會導致長期的穩定時期，這些時期被危機和對環境微小變化極度敏感所打破，可能成為經濟系統複雜性的隱喻。我認為物理學對經濟學最寶貴的貢獻最終可能是方法論性的，簡單的物理模型和基於代理的數值模擬，雖然高度簡化，但比傳統經濟學模型更現實，這些模型假設理性代理人具有無限的遠見和無限的計算能力。 显示英文摘要

摘要： This article is a follow-up of a short essay that appeared in Nature 455, 1181 (2008) [arXiv:0810.5306]. It has become increasingly clear that the erratic dynamics of markets is mostly endogenous and not due to the rational processing of exogenous news. I elaborate on the idea that spin-glass type of problems, where the combination of competition and heterogeneities generically leads to long epochs of statis interrupted by crises and hyper-sensitivity to small changes of the environment, could be metaphors for the complexity of economic systems. I argue that the most valuable contribution of physics to economics might end up being of methodological nature, and that simple models from physics and agent based numerical simulations, although highly stylized, are more realistic than the traditional models of economics that assume rational agents with infinite foresight and infinite computing abilities.