Shan Gao

Shanxi University
  • Shanxi University
    Research Center For Philosophy Of Science And Technology
    Professor
University of Sydney
Department of Philosophy
PhD, 2013
Areas of Interest
Philosophy of Mind
  •  9
    Why the Global Phase is Not Real
    Foundations of Physics 54 (2): 1-6. 2024.
    In this paper, I present a new analysis of the meaning of the phase in quantum mechanics. First, I give a simple but rigorous proof that the global phase is not real in \(\psi\) -ontic quantum theories. Next, I argue that a similar strategy cannot be used to prove the reality of the global phase due to the existence of the tails of the wave function. Finally, I argue that the relative phase is not a nonlocal property of two regions together, and adding a relative phase to one local branch of a s…Read more
  •  5
    Is the Universe in a Mixed State?
    Foundations of Physics 54 (1): 1-7. 2023.
    Quantum mechanics with a fundamental density matrix has been proposed and discussed recently. Moreover, it has been conjectured that the universe is not in a pure state but in a mixed state in this theory. In this paper, I argue that this mixed state conjecture has two main problems: the redundancy problem and the underdetermination problem, which are lacking in quantum mechanics with a definite initial wave function of the universe.
  •  19
    The meaning of the wave function is an important unresolved issue in Bohmian mechanics. On the one hand, according to the nomological view, the wave function of the universe or the universal wave function is nomological, like a law of nature. On the other hand, the PBR theorem proves that the wave function in quantum mechanics or the effective wave function in Bohmian mechanics is ontic, representing the ontic state of a physical system in the universe. It is usually thought that the nomological…Read more
  •  7
    It is a received view that superluminal signaling is prohibited in collapse theories of quantum mechanics. In this paper, I argue that this may be not the case. I propose two possible mechanisms of superluminal signaling in collapse theories. The first one is based on the well-accepted solution to the tails problem, and the second one is based on certain assumptions about the minds of observers. Finally, I also discuss how collapse theories can avoid such superluminal signaling.
  •  5
    Quantum mechanics and experience -- The wave function: ontic vs epistemic -- The nomological view -- Reality of the wave function -- Origin of the Schrödinger equation -- The ontology of quantum mechanics (I) -- The ontology of quantum mechanics (II) -- Implications for solving the measurement problem -- Quantum ontology and relativity.
  •  10
    Can Pragmatist Quantum Realism Explain Protective Measurements?
    Foundations of Physics 53 (1): 1-6. 2022.
    According to Healey’s pragmatist quantum realism, the only physical properties of quantum systems are those to which the Born rule assigns probabilities. In this paper, I argue that this approach to quantum theory fails to explain the results of protective measurements.
  •  20
    Understanding Time Reversal in Quantum Mechanics: A New Derivation
    Foundations of Physics 52 (5): 1-7. 2022.
    Why does time reversal involve two operations, a temporal reflection and the operation of complex conjugation? Why is it that time reversal preserves position and reverses momentum and spin? This puzzle of time reversal in quantum mechanics has been with us since Wigner’s first presentation. In this paper, I propose a new solution to this puzzle. First, it is shown that the standard account of time reversal can be derived based on the assumption that the probability current is reversed by the ti…Read more
  •  24
    On Bell’s Everett (?) Theory
    Foundations of Physics 52 (4): 1-7. 2022.
    Bell’s Everett theory is Bell’s interpretation of Everett’s theory, aiming to remove the picture of many worlds from the theory. In this paper, I argue that Bell’s Everett theory as a one-world theory contradicts quantum mechanics and experiments. Moreover, I argue that a proper understanding of this theory also leads to a picture of many worlds, and this many-worlds theory agrees with experiments.
  •  23
    Is Retrocausal Quantum Mechanics Consistent with Special Relativity?
    Foundations of Physics 52 (1): 1-4. 2022.
    Retrocausal quantum mechanics (RQM) provides a local causal explanation of Bell correlations. It is widely thought that RQM is consistent with special relativity. In this paper, I point out that this view is not wholly right. It is argued that RQM violates the Lorentz invariance of the temporal relation between cause and effect for certain spacelike separated events in Bell-type experiments.
  •  18
    A No-Go Result for QBism
    Foundations of Physics 51 (5): 1-6. 2021.
    In QBism the wave function does not represent an element of physical reality external to the agent, but represent an agent’s personal probability assignments, reflecting his subjective degrees of belief about the future content of his experience. In this paper, I argue that this view of the wave function is not consistent with protective measurements. The argument does not rely on the realist assumption of the ψ-ontology theorems, namely the existence of the underlying ontic state of a quantum s…Read more
  •  64
    Consciousness and Quantum Mechanics (edited book)
    Oxford University Press, Usa. 2022.
    Consciousness and quantum mechanics are two great mysteries of our time--and recently scholars have postulated a deeper connection between them. Exploring this possible connection can be fruitful: an analysis of the conscious mind and psychophysical connection can be indispensable in understanding quantum mechanics and solving the notorious measurement problem, and there is also likely some kind of intimate connection between quantum mechanics--the most fundamental theory of the physical world--…Read more
  •  17
    Nature, Wilderness, and Supreme Goodness
    Environmental Ethics 42 (3): 237-251. 2020.
    Transcendentalism and Confucianism involve different understandinsgs of the concepts of nature, wilderness, and supreme goodness in terms of the metaphysical understanding of nature and how it influences the understanding of human nature. The goodness of Tao is not transcendental as understood by transcendentalism. Rather the goodness of Tao as the important moral values is shaped by human beings’ experience of the natural world. It is this deeper philosophical reason why transcendentalism encou…Read more
  •  8
    Nature, Wilderness, and Civilization
    Environmental Ethics 42 (3): 211-212. 2020.
  •  65
    Does Quantum Cognition Imply Quantum Minds?
    Journal of Consciousness Studies 28 (3-4): 100-111. 2021.
    Quantum cognition is a new theoretical framework for constructing cognitive models based on the mathematical principles of quantum theory. Due to its increasing empirical success, one wonders what it tells us about the underlying process of cognition. Does it imply that we have quantum minds and there is some sort of quantum structure in the brain? In this paper, I address this important issue by using a new result in the research of quantum foundations. Based on the PBR theorem about the realit…Read more
  •  9
    Existence of macroscopic spatial superpositions in collapse theories
    Studies in History and Philosophy of Science Part A 86 (C): 1-5. 2021.
  •  34
    A Puzzle for the Field Ontologists
    Foundations of Physics 50 (11): 1541-1553. 2020.
    It has been widely thought that the wave function describes a real, physical field in a realist interpretation of quantum mechanics. In this paper, I present a new analysis of the field ontology for the wave function. First, I argue that the non-existence of self-interactions for a quantum system such as an electron poses a puzzle for the field ontologists. If the wave function represents a physical field, then it seems odd that there are (electromagnetic and gravitational) interactions between …Read more
  •  30
    Criticism in a foreign language hurts less
    with Lizhu Luo and Ting Gou
    Cognition and Emotion 34 (4): 822-830. 2019.
    Understanding emotional resonances to social evaluations delivered in different languages may contribute to favourable social communication in today’s increasingly internationalised world. The pres...
  •  40
    Understanding Scientific Progress: Aim-oriented Empiricism (review)
    International Studies in the Philosophy of Science 31 (4): 435-438. 2017.
    Volume 31, Issue 4, December 2017, Page 435-438.
  •  32
    It is argued that the result assumption of Bohm's theory, which says that particle configurations represent measurement results, contradicts the predictions of the Schroedinger equation.
  •  40
    The measurement problem revisited
    Synthese 196 (1): 299-311. 2019.
    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 mea…Read more
  •  34
    The many-worlds interpretation of quantum mechanics is based on three key assumptions: the completeness of the physical description by means of the wave function, the linearity of the dynamics for the wave function, and multiplicity. In this paper, I argue that the combination of these assumptions may lead to a contradiction. In order to avoid the contradiction, we must drop one of these key assumptions.
  •  29
    In collapse theories of quantum mechanics such as the GRW theory, the measurement result is represented by the post-measurement state which is still a superposition of different result branches, although the modulus squared of the amplitude of one result branch is close to one. This leads to the tails problem. In this paper, I present a new analysis of the tails problem of collapse theories, and suggest a more complete solution to the problem. First, I argue that the tails problem exists not onl…Read more
  •  25
    It has been widely thought that the ontology of quantum mechanics is real, physical fields. In this paper, I will present a new argument against the field ontology of quantum mechanics by analyzing one-body systems such as an electron. First, I argue that if the physical entity described by the wave function of an electron is a field, then this field is massive and charged. Next, I argue that if a field is massive and charged, then any two parts of the field in space will have gravitational and …Read more
  •  40
    From Intrinsic Value to the Emotion of Wonder
    Environmental Ethics 40 (1): 81-91. 2018.
    Since environmental ethics research started in China in the 1980s, it has been deeply influenced by environmental ethics theory in the United States. Some Chinese environmental philosophers have adopted the key concept of intrinsic value to construct Chinese environmental ethics. However, in recent decades, the concept of intrinsic value has been criticized by scholars in both the United States and China. Many Chinese have found that environmental ethics in the United States that is founded on t…Read more
  •  16
    Healey recently argued that a version of the extended Wigner's friend Gedankenexperiment due to Masanes establishes a contradiction between the universal applicability of unitary quantum theory and the assumption of definite outcomes [Found. Phys. 48, 1568 ]. In this Comment, I show that Healey's analysis is problematic and his conclusion is not true.
  •  63
    It is shown that the combination of unitary quantum theory and special relativity may lead to a contradiction when considering the EPR correlations in different inertial frames in a Gedankenexperiment. This result seems to imply that either unitary quantum theory is wrong or if unitary quantum theory is right then there must exist a preferred Lorentz frame.
  •  18
    It has been debated whether protective measurement implies the reality of the wave function. In this paper, I present a new analysis of the relationship between protective measurement and the reality of the wave function. First, I briefly introduce protective measurements and the ontological models framework for them. Second, I give a simple proof of Hardy's theorem in terms of protective measurements. It shows that when assuming the ontic state of the protected system keeps unchanged during a p…Read more