Shan Gao

Social egg freezing (SEF) refers to the act of a woman’s voluntary decision to preserve her eggs for future use. It is considered an expression of her right to bodily autonomy, allowing her to make decisions about her own reproductive capacity. As a form of exercising personal rights, SEF is aimed at preserving or extending fertility. Owing to the difference in attributes between it and the traditional “medical act,” SEF has sparked significant controversies in the academic world that remain unresolved. These debates stem from uncertainty and are often framed through the lens of consequentialist theory—focusing on potential social, ethical, or medical outcomes. For SEF, a more appropriate position should be taken, based on the theory of rights. This perspective centres on the individual’s legitimate claim to exercise bodily autonomy, particularly in relation to their reproductive potential. SEF is essentially a specific claim by a woman to exercise her right to control her own body as a means of realising her autonomy over her own eggs. To avoid the abuse of SEF, necessary legal regulations should be put in place.

The Pusey–Barrett–Rudolph (PBR) theorem establishes $\psi$-onticity for individual quantum systems, but its standard formulation relies on the Preparation Independence Postulate (PIP). This has led to a prevalent view that rejecting PIP leaves open the possibility of $\psi$-epistemic models for individual systems. In this work, we show that this understanding is incomplete: once the PBR theorem establishes $\psi$-onticity for composite systems prepared in product states, the $\psi$-onticity of the individual subsystems follows directly from the tensor-product structure of quantum mechanics, without invoking PIP or any further auxiliary assumptions. This result removes a key auxiliary assumption from the PBR theorem, closes a persistent loophole for preserving $\psi$-epistemic models, and strengthens the conceptual foundations of $\psi$-ontology.

The Pusey–Barrett–Rudolph (PBR) theorem establishes $$\psi$$-onticity for individual quantum systems, but its standard formulation relies on the Preparation Independence Postulate (PIP). This has led to a prevalent view that rejecting PIP leaves open the possibility of $$\psi$$-epistemic models for individual systems. In this work, we show that this understanding is incomplete: once the PBR theorem establishes $$\psi$$-onticity for composite systems prepared in product states, the $$\psi$$-onticity of the individual subsystems follows directly from the tensor-product structure of quantum mechanics, without invoking PIP or any further auxiliary assumptions. This result removes a key auxiliary assumption from the PBR theorem, closes a persistent loophole for preserving $$\psi$$-epistemic models, and strengthens the conceptual foundations of $$\psi$$-ontology.

The Pusey–Barrett–Rudolph (PBR) theorem establishes $$\psi$$ -onticity for individual quantum systems, but its standard formulation relies on the Preparation Independence Postulate (PIP). This has led to a prevalent view that rejecting PIP leaves open the possibility of $$\psi$$ -epistemic models for individual systems. In this work, we show that this understanding is incomplete: once the PBR theorem establishes $$\psi$$ -onticity for composite systems prepared in product states, the $$\psi$$ -onticity of the individual subsystems follows directly from the tensor-product structure of quantum mechanics, without invoking PIP or any further auxiliary assumptions. This result removes a key auxiliary assumption from the PBR theorem, closes a persistent loophole for preserving $$\psi$$ -epistemic models, and strengthens the conceptual foundations of $$\psi$$ -ontology.

The Aharonov-Bohm (AB) effect highlights the fundamental role of electromagnetic potentials in quantum mechanics, manifesting as a phase shift for a charged particle in field-free regions. While well-established for static magnetic fluxes, the effect’s behavior under time-varying fluxes remains an open and debated question. Employing the WKB method, we derive the AB phase shift for a time-dependent magnetic vector potential, demonstrating that for circular paths in the quasistatic regime, it is proportional to the time-averaged enclosed magnetic flux, $$\Delta \phi _\textrm{AB} = \frac{1}{T} \int _0^T e \Phi (t) \, dt$$, with the total phase shift, including kinetic contributions, equaling $$e \Phi (0)$$. For non-circular paths, the phase shift depends on both the flux history and path geometry, revealing the effect’s hybrid nature involving gauge potentials and induced electric fields. We verify the consistency of our gauge choice with Maxwell’s equations and discuss the implications for local versus nonlocal interpretations of the AB effect. We also generalize the results to scenarios with nonzero external magnetic fields, where the enclosed flux is through the actual electron paths, and for circular paths of radius _R_, the AB phase shift is also proportional to the time average of the enclosed flux $$\Phi _\textrm{enc}(R,t)$$, with the total phase shift depending only on the initial enclosed flux $$e \Phi _\textrm{enc}(R,0)$$; for general non-circular paths, the external magnetic field affects trajectories and phase accumulation through the Lorentz force, leading to additional path dependence. These findings clarify the role of gauge-dependent potentials and induced fields in the generalized AB effect, offering new theoretical insights and potential applications in quantum technologies.

Sebens and Carroll (Br. J. Philos. Sci. 69(1), 25–74 1) propose that self-locating uncertainty, constrained by their quantum-specific Epistemic Separability Principle (ESP-QM), derives Born rule probabilities in Everettian quantum mechanics through a global branching model. This paper argues that their approach fails due to the loss of local amplitude information in global branching, particularly evident in an EPR-Bohm setup, where distant observers like Bob are assigned pure local states lacking the amplitude coefficients essential for Born rule probabilities. This flaw undermines the quantitative link to the Born rule, rendering their derivation empirically inadequate. Additional inconsistencies of global branching, including conflicts with decoherence dynamics, relativistic constraints, and limitations on superposition measurements, further weaken the model. Defenses invoking global amplitudes or benign non-locality fail to resolve these issues. This analysis underscores the need to reconsider branching mechanisms to secure a robust foundation for Everettian probabilities.

The Pusey-Barrett-Rudolph (PBR) theorem proves that the joint wave function ψ1 ⊗ψ2 of a composite quantum system is ψ-ontic, representing the system’s physical reality. We present a minimalist proof showing that this result, combined with the tensor product structure assigning ψ1 to subsystem 1 and ψ2 to subsystem 2, directly implies that ψ1 and ψ2 are ψ-ontic for their respective subsystems. This establishes ψ-ontology for single quantum systems without requiring preparation independence or other assumptions. Our proof challenges the widely held view that joint ψ-onticity permits subsystem ψ-epistemicity via correlations, providing a simpler, more direct understanding of the wave function’s ontological status in quantum mechanics.

In a recent reply to my criticisms (Carcassi et al. in Found Phys 55:5, 2025), Carcassi, Oldofredi, and Aidala (COA) admitted that their no-go result for ψ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\psi $$\end{document}-ontic models is based on the implicit assumption that all states are equally distinguishable, but insisted that this assumption is a part of the ψ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\psi $$\end{document}-ontic models defined by Harrigan and Spekkens, thus maintaining their result’s validity. In this note, I refute their argument again, emphasizing that the ontological models framework (OMF) does not entail this assumption. I clarify the distinction between ontological distinctness and experimental distinguishability, showing that the latter depends on dynamics absent from OMF, and address COA’s broader claims about quantum statistical mechanics and Bohmian mechanics.

In collapse theories of quantum mechanics, there exist quantum observers who are observers being in a superposition of different result branches. In this paper, I analyze the mental state of a quantum observer. First, I argue that the mental state of a quantum observer is not the usual state of recording one of the results in the superposition, but it is definite. Second, I argue that the mental state of a quantum observer is determined by both the amplitudes and relative phases of the result branches of the superposition, and the mental content is composed of every result. Third, I argue that there are new mental properties which are lack for classical observers and determined by the amplitude and relative phase. In particular, the mental property determined by the amplitude may be a certain property of vividness of the mental content; the bigger the amplitude of a result branch, the more vivid the result is in the whole mental content. Finally, I argue that the new experience of a quantum observer, which violates quantum mechanics, implies that consciousness is not physically reducible or emergent but fundamental in collapse theories.

In a recent reply to my criticisms (Carcassi et al. in Found Phys 55:5, 2025), Carcassi, Oldofredi, and Aidala (COA) admitted that their no-go result for $$\psi $$ -ontic models is based on the implicit assumption that all states are equally distinguishable, but insisted that this assumption is a part of the $$\psi $$ -ontic models defined by Harrigan and Spekkens, thus maintaining their result’s validity. In this note, I refute their argument again, emphasizing that the ontological models framework (OMF) does not entail this assumption. I clarify the distinction between ontological distinctness and experimental distinguishability, showing that the latter depends on dynamics absent from OMF, and address COA’s broader claims about quantum statistical mechanics and Bohmian mechanics.

Hargrove’s ontological argument for Aesthetic Foundation of Wilderness Preservation was the extension of the thinking paradigm from human beings to moral consideration and aesthetic appreciation of wilderness. The thinking paradigm was based on the framework of traditional Western philosophy, which includes metaphysics, epistemology, and ethics. In this article, I will examine Hargrove’s ontological argument by making a little comparison with the perspective of a Chinese philosophical framework. This paper will be divided into three parts. In the part I, I will summarize Hargrove’s ontological argument for natural beauty and environmental preservation. In part II, I will examine the metaphysical framework in Hargrove’s ontological argument. I argue it is the extension of Plato’s metaphysics of the ultimate reality to wilderness. In Part III, I will examine the ethical and aesthetic framework in his ontological argument. I point out Hargrove’s ethical framework comes from ethical rationalism and his aesthetic framework is the legacy of Plato’s aesthetics. By comparison, Chinese metaphysics stresses the process and Chinese ethics stresses care. The two different directions promote the aesthetic appreciation of agricultural land rather than wilderness.

In a recent paper (Found Phys 54:14, 2024), Carcassi, Oldofredi and Aidala concluded that the \(\psi\) -ontic models defined by Harrigan and Spekkens cannot be consistent with quantum mechanics, since the information entropy of a mixture of non-orthogonal states are different in these two theories according to their information theoretic analysis. In this paper, I argue that this no-go theorem for \(\psi\) -ontic models is false by explaining the physical origin of the von Neumann entropy in quantum mechanics.

The remarkable connections between gravity and thermodynamics seem to imply that gravity is not fundamental but emergent, and in particular, as Verlinde suggested, gravity is probably an entropic force. In this paper, we will argue that the idea of gravity as an entropic force is debatable. It is shown that there is no convincing analogy between gravity and entropic force in Verlinde’s example. Neither holographic screen nor test particle satisfies all requirements for the existence of entropic force in a thermodynamics system. Furthermore, we show that the entropy increase of the screen is not caused by its statistical tendency to increase entropy as required by the existence of entropic force, but in fact caused by gravity. Therefore, Verlinde’s argument for the entropic origin of gravity is problematic. In addition, we argue that the existence of a minimum size of spacetime, together with the Heisenberg uncertainty principle in quantum theory, may imply the fundamental existence of gravity as a geometric property of spacetime. This may provide a further support for the conclusion that gravity is not an entropic force.

Psychophysical supervenience requires that the mental properties of a system cannot change without the change of its physical properties. In this paper, I argue that the Everett interpretation of quantum mechanics or Everett's theory seems to violate the principle of psychophysical supervenience. In order to be consistent with our experience, the theory assumes psychophysical supervenience in each world, including our world. However, this permits the possibility that under certain unitary time evolution which does not lead to world branching, the wave function of each world changes and correspondingly the mental states of the observers in the world also change, while the wave function of the total worlds does not change, which violates the principle of psychophysical supervenience for all worlds. It seems that one must go beyond Everett's theory such as denying multiplicity in order to avoid the failure of psychophysical supervenience.

We investigate the validity of the field explanation of the wave function by analyzing the mass and charge density distributions of a quantum system. It is argued that a charged quantum system has effective mass and charge density distributing in space, proportional to the square of the absolute value of its wave function. This is also a consequence of protective measurement. If the wave function is a physical field, then the mass and charge density will be distributed in space simultaneously for a charged quantum system, and thus there will exist a remarkable electrostatic self-interaction of its wave function, though the gravitational self-interaction is too weak to be detected presently. This not only violates the superposition principle of quantum mechanics but also contradicts experimental observations. Thus we conclude that the wave function cannot be a description of a physical field. In the second part of this paper, we further analyze the implications of these results for the main realistic interpretations of quantum mechanics, especially for de Broglie-Bohm theory. It has been argued that de Broglie-Bohm theory gives the same predictions as quantum mechanics by means of quantum equilibrium hypothesis. However, this equivalence is based on the premise that the wave function, regarded as a Ψ-field, has no mass and charge density distributions, which turns out to be wrong according to the above results. For a charged quantum system, both Ψ-field and Bohmian particle have charge density distribution. This then results in the existence of an electrostatic self-interaction of the field and an electromagnetic interaction between the field and Bohmian particle, which contradicts both the predictions of quantum mechanics and experimental observations. Therefore, de Broglie-Bohm theory as a realistic interpretation of quantum mechanics is probably wrong. Lastly, we suggest that the wave function is a description of some sort of ergodic motion (e.g. random discontinuous motion) of particles, and we also briefly analyze the implications of this suggestion for other realistic interpretations of quantum mechanics including many-worlds interpretation and dynamical collapse theories.

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 encourages the aesthetic appreciation of wilderness while Confucianism encourages the aesthetic appreciation of humanized nature.

We analyze the possible implications of spacetime discreteness for the special and general relativity and quantum theory. It is argued that the existence of a minimum size of spacetime may explain the invariance of the speed of light in special relativity and Einstein’s equivalence principle in general relativity. Moreover, the discreteness of spacetime may also result in the collapse of the wave function in quantum mechanics, which may provide a possible solution to the quantum measurement problem. These interesting results might have some important implications for a complete theory of quantum gravity.

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 reality of the wave function, I show, given certain assumptions, that the wave function assigned to a cognitive system such as our brain, which is used to calculate probabilities of thoughts/judgment outcomes in quantum cognition, is a real representation of the cognitive state of the system, not a mere representation of incomplete knowledge about the state of the system. This result supports a realist interpretation of quantum cognition, according to which the cognitive state of our brain and its dynamics are not classical but quantum in quantum cognition. In short, quantum cognition implies quantum minds. However, this result does not mean that we have quantum minds and our brain is a quantum computer, since quantum cognition by its standard formulation has not been fully confirmed by experiments. The hope is that more crucial experiments can be done in the near future to determine whether or not quantum cognition is real.

The ontological model framework provides a rigorous approach to address the question of whether the quantum state is ontic or epistemic. When considering only conventional projective measurements, auxiliary assumptions are always needed to prove the reality of the quantum state in the framework. For example, the Pusey-Barrett-Rudolph theorem is based on an additional preparation independence assumption. In this paper, we give a new proof of psi-ontology in terms of protective measurements in the ontological model framework. It is argued that the proof needs not rely on auxiliary assumptions, and also applies to deterministic theories such as the de Broglie-Bohm theory. In addition, we give a simpler argument for psi-ontology beyond the framework, which is only based on protective measurements and a weaker criterion of reality. The argument may be also appealing for those people who favor an anti-realist view of quantum mechanics.

Protective measurement is a new measuring method introduced by Aharonov, Anandan and Vaidman. By a protective measurement, one can measure the expectation value of an observable on a single quantum system, even if the system is initially not in an eigenstate of the measured observable. This remarkable feature of protective measurements was challenged by Uffink. He argued that only observables that commute with the system's Hamiltonian can be protectively measured, and a protective measurement of an observable that does not commute with the system's Hamiltonian does not actually measure the observable, but measure another related observable that commutes with the system's Hamiltonian. In this paper, we show that there are several errors in Uffink's arguments, and his alternative interpretation of protective measurements is untenable.

We suggest a new answer to this intriguing question and argue that the answer may have implications for the solutions to the measurement problem. The main basis of our analysis is the doctrine of psychophysical supervenience. First of all, based on this doctrine, we argue that an observer in a quantum superposition or a quantum observer has a definite conscious experience, which is neither disjunctive nor illusive. The inconsistency of this result with the bare theory is further analyzed, and it is shown that an appropriate use of the strategy of analyzing the disposition of an observer to answer a particular question also leads to the same result. Next, we argue that this new result seems to disfavor Everett's and Bohm's approaches to quantum mechanics when considering the doctrine of psychophysical supervenience. This suggests that dynamical collapse theories are in the right direction to solve the measurement problem. Thirdly, we analyze the concrete content of the conscious experience of a quantum observer. It is argued that the mental content of a quantum observer is related to both the amplitude and relative phase of each branch of the superposition she is physically in, and it is composed of the mental content corresponding to every branch of the superposition. In addition, we argue that when assuming the modulus squared of the amplitude of each branch determines the vividness of the mental content corresponding to the branch, the structured tails problem of dynamical collapse theories can be solved.

It is shown that the de Broglie-Bohm theory has a potential problem concerning the mass and charge distributions of a quantum system such as an electron. According to the de Broglie-Bohm theory, the mass and charge of an electron are localized in a position where its Bohmian particle is. However, protective measurement indicates that they are not localized in one position but distributed throughout space, and the mass and charge density of the electron in each position is proportional to the modulus square of its wave function there.