## Abstract

It has been realized that the measurement problem of quantum mechanics is essentially the determinate-experience problem, and in order to solve the problem, the physical state representing the measurement result is required to be also the physical state on which the mental state of an observer supervenes. This necessitates a systematic analysis of the forms of psychophysical connection in the solutions to the measurement problem. In this paper, I propose a new, mentalistic formulation of the measurement problem which lays more stress on psychophysical connection. By this new formulation, it can be seen more clearly that the three main solutions to the measurement problem, namely Everett’s theory, Bohm’s theory and collapse theories, correspond to three different forms of psychophysical connection. I then analyze these forms of psychophysical connection. It is argued that the forms of psychophysical connection required by Everett’s and Bohm’s theories have potential problems, while an analysis of how the mental state of an observer supervenes on her wave function may help solve the structured tails problem of collapse theories.

## Keywords

Measurement problem Psychophysical supervenience Everett’s theory Bohm’s theory Collapse theories Structured tails problem## Notes

### Acknowledgements

I am very grateful to two anonymous referees of this journal for their insightful comments, constructive criticisms and helpful suggestions. The basic idea of this paper came to my mind when I taught the course *The Philosophy of Quantum Mechanics* to the postgraduates at the University of Chinese Academy of Sciences. I thank the International Conference Center of the University for providing comfortable accommodation. I am also grateful to Arthur Fine, Kelvin McQueen, Peter Lewis, Mark Stuckey, and Ken Wharton for helpful discussions at the 2016 International Workshop on Quantum Observers hosted by *International Journal of Quantum Foundations*. This work is partly supported by a research project grant from Chinese Academy of Sciences and the National Social Science Foundation of China (Grant No. 16BZX021).

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