标题： 密度矩阵现实主义 显示英文标题

标题： Density Matrix Realism

摘要： 量子理论的实在论自然地导致对宇宙量子态的实在论。 它没有说明这个量子态是用波函数表示的纯态，还是用密度矩阵表示的非纯（混合）态。 我描述并详细阐述了密度矩阵实在论，即宇宙量子态是客观的，但可以是非纯的这一观点。 为了澄清这一观点， 我将其与波函数实在论进行比较，解释它们在何种条件下具有经验等价性，考虑密度矩阵实在论的两种推广形式，并回答一些常见问题。 最后，我强调了这对科学实在论的一个含义。 显示英文摘要

摘要： Realism about quantum theory naturally leads to realism about the quantum state of the universe. It leaves open whether it is a pure state represented by a wave function, or an impure (mixed) one represented by a density matrix. I characterize and elaborate on Density Matrix Realism, the thesis that the universal quantum state is objective but can be impure. To clarify the thesis, I compare it with Wave Function Realism, explain the conditions under which they are empirically equivalent, consider two generalizations of Density Matrix Realism, and answer some frequently asked questions. I end by highlighting an implication for scientific realism.