About
I run the Foundations of Thermodynamics Group at NTU Singapore, which is currently funded by the Nanyang Assistant Professorship Grant. Its goal is to provide a space for research on all aspects of the conceptual foundations of thermodynamics, with particular focus on understanding the conceptual foundations of thermodynamics beyond the classical domain, e.g., in the quantum and relativistic domains, how thermodynamics relates to other non-fundamental domains such as fluid dynamics and neuroscience, and how it bears on questions in philosophy such as (but not limited to) questions about emergence, reduction, inter-theory relations, the nature of non-fundamental reality, the laws of nature, and the relation between symmetries and reality.
The group is currently supported by Research Associate Melissa Ong. We are in the midst of hiring two postdoctoral Research Fellows. Stay tuned for more news!
2025 Foundations of Thermodynamics Workshop
Nanyang Technological University Singapore
16-18 July 2025
Venue: NTU School of Humanities, room TBD
Organizers: Eugene Y. S. Chua (Nanyang Technological University) and
Wayne Myrvold (University of Western Ontario)
In collaboration with Wayne Myrvold from the University of Western Ontario, the Foundations of Thermodynamics Group will be organizing the Foundations of Thermodynamics Workshop 2025. The first two days will feature a series of talks on the philosophy of thermodynamics and statistical mechanics, while the last day will feature a roundtable discussion on the status of the two dominant approaches to understanding statistical mechanics, the Gibbsian and Boltzmannian approaches.
Attendance is free, but space is limited. Please contact me at eugene.chuays@ntu.edu.sg to indicate interest.
The Quantum Thermodynamics 2025 (QTD2025) Conference will be held the week before the workshop, on 7-11 July 2025. Afficionados of thermodynamics are encouraged to attend the conference, which will be held at the National University of Singapore. Details and registration here: https://qtd2025.quantumlah.org/
Speakers and Abstracts
(Schedule TBD)
Eddy Keming Chen (UC San Diego)
Typical Quantum States of the Universe are Observationally Indistinguishable
This paper, which is joint work with Roderich Tumulka, is about the epistemology of quantum theory. We establish a new result about a limitation to knowledge of its central object --- the quantum state of the universe. We show that, if the universal quantum state can be assumed to be a typical unit vector from a high-dimensional subspace of Hilbert space (such as the subspace defined by a low-entropy macro-state as prescribed by the Past Hypothesis), then no observation can determine (or even just narrow down significantly) which vector it is. Typical state vectors, in other words, are observationally indistinguishable from each other. Our argument is based on a typicality theorem from quantum statistical mechanics. We also discuss how theoretical considerations that go beyond the empirical evidence might bear on this fact and on our knowledge of the universal quantum state.
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Roman Frigg (London School of Economics and Political Science) - by Zoom
Roundtable Discussant
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Bixin Guo (Macalester College)
Making Sense of Statistical Mechanics: The Gibbsian vs the Boltzmannian Approach
In the literature on the foundations of statistical mechanics, we find two main approaches: the so-called Boltzmannian approach and the Gibbsian approach. The Boltzmannian approach has been defended extensively in philosophy of physics literature. In contrast, less attention has been paid to the Gibbsian approach, which is often criticized as conceptually unsatisfactory, and dismissed as a set of mathematical tools, rather than as a physical theory that describes what is actually going on in thermodynamic systems. In response, I argue for the physical significance of the Gibbsian approach, and formulate a new proposal regarding its relationship with the Boltzmannian approach. I argue that statistical mechanics is a framework theory, which covers a wide range of concrete theories of different kinds of systems. In contrast, the Boltzmannian approach faces challenges in achieving such broad applicability, and is thus better viewed as a concrete theory that applies only to certain physical systems.
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Patricia Palacios (University of Salzburg)
Something's Gotta Give: Empirical and Non-Empirical Strategies to Cope with Information Loss
According to theoretical calculations, black holes lose energy due to Hawking radiation, and eventually evaporate. This gives rise to what is known as the "information loss paradox": according to quantum mechanics, it should be possible, from a complete specification of the quantum state at a later time, to recover states at earlier time, but the post-evaporation state apparently contains no details about the matter that fell into the black hole. This is one of the most outstanding issues in contemporary physics, as it reveals contradictions between quantum mechanics and general relativity. In this contribution, I will analyze the use of different alternative empirical and non-empirical methods to cope with the puzzle of information loss. Although I will argue that the resolution will largely depend on our preferred theory, I will stress the role of analogue experiments, thought experiments and intertheory reduction for choosing a particular resolution to the paradox.
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Katie Robertson (Stirling University) - by Zoom
Roundtable Discussant
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Jos Uffink (University of Minnesota)
The "schism" between Boltzmannian and Gibbsian Statistical Mechanics
Drawing upon (Uffink 2007), I will review the conceptual structure of both the Boltzmannian and Gibbsian approach to Statistical Mechanics, and highlight their most important differences. I will next discuss the ways in which more recent authors have characterized the relationship between these two approaches (e.g.: Werndl & Frigg 2018; Lazarovici 2018, Frigg & Werndl 2019, Anta 2021). From this discussion I hope to clarify the relationship between these two approaches and draw conclusions about which one is preferable depending, of course, on a choice of desiderata.
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Giovanni Valente (Polytechnic University of Milan)
On the Quantum Boltzmann Equation: What is the Source, if any, of Irreversibility?
In this talk, based on joint work with Jos Uffink, I provide a philosophical analysis of the Quantum Boltzmann Equation (QBE). The question addressed is: Given that the underlying microscopic dynamics is time-reversal invariant, what, if anything, is the source of irreversibility at the macroscopic level? Snoke at al. (2012) and Snoke (2020) claim that irreversibility stems from an assumption we call "Zero Off-diagonal Terms", from which one derives a factorization condition akin to the classical Stosszahlansatz. However, we contend that, contrary to the latter, whereby factorization is assumed only for particles before collision, in the quantum case factorization holds for all pre- and post-scattering states, and thus this condition is neutral with respect to the direction of time. As such, it cannot be responsible for irreversibility. Since there is no other time asymmetric ingredient in the derivation of QBE, we argue that the equation is fully time-reversal invariant.
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David Wallace (University of Pittsburgh)
What Gibbsian Statistical Mechanics Actually Says: Defending Bare Probabilism
I expound and defend the "bare probabilism" reading of Gibbsian (i.e. mainstream) statistical mechanics, responding to Frigg and Werndl's recent (BJPS 72 (2021), 105-129) plea: "can somebody please say what Gibbsian statistical mechanics says?"
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Charlotte Werndl (University of Salzburg) - by Zoom
The Boltzmann equation and its place in the edifice of statistical mechanics
It is customary to classify approaches in statistical mechanics (SM) as belonging either to Boltzmanninan SM (BSM) or Gibbsian SM (GSM). It is, however, unclear how the Boltzmann equation (BE) fits into either of these approaches. To discuss the relation between BE and BSM, we first present a version of BSM that differs from standard presentation in that it uses local field variables to individuate macro-states, and we then show that BE is a special case of BSM thus understood. To discuss the relation between BE and GSM, we focus on the BBGKY hierarchy and note the version of the BE that follows from the hierarchy is "Gibbsian" only in the minimal sense that it operates with an invariant measure on the state space of the full system.