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I am a Singaporean PhD student in Philosophy at UCSD.

I work mostly on philosophy of physics and philosophy of science, with particular interests in the philosophy of thermodynamics and the conceptual knot that is entropy, and the use of approximations and idealizations in physics.

On the side, I dabble in formal epistemology, data ethics and the philosophy of data science, and the philosophy of logic and mathematics. 


I completed my undergraduate studies in Philosophy at Wolfson College, University of Cambridge, and spent some time at the Munich Center for Mathematical Philosophy before arriving at UCSD for my PhD. My CV can be found here

When I am not doing philosophy, I can be found playing Magic the Gathering at my local game store, playing video games on my console/PC, or learning a new hobby. (current hobby: skateboarding)

 

Education

2018 -

PhD Philosophy, 
University of California San Diego

2017 - 2018

MA Logic and Philosophy of Science, 
Munich Center for Mathematical Philosophy (Incomplete)

2014 - 2017

MA (Cantab) Philosophy,
University of Cambridge

 

Publications

Does Von Neumann Entropy Correspond to Thermodynamic Entropy? 
(Philosophy of Science 2021 88:1, 145-168)

Conventional wisdom holds that the von Neumann entropy corresponds to thermodynamic entropy, but Hemmo and Shenker (2006) have recently argued against this view by attacking von Neumann's (1955) argument. I argue that Hemmo and Shenker's arguments fail due to several misunderstandings: about statistical mechanical and  thermodynamic domains of applicability, about the nature of mixed states, and about the role of approximations in physics. As a result, their arguments fail in all cases: in the single-particle case, the finite-particles case, and the infinite-particles case.

No Time for Time from No-Time

(with Craig Callender, Forthcoming at Philosophy of Science)

Programs in quantum gravity often claim that time emerges from fundamentally timeless physics. In the semiclassical time program time arises only after approximations are taken. Here we ask what justifies taking these approximations and show that time seems to sneak in when answering this question. This raises the worry that the approach is either unjustified or circular in deriving time from no–time.

Improving LIME Robustness with Smarter Locality Sampling 
(2020, with Sean Saito, Rocco Hu and Nicholas Capel, AdvML '20: Workshop on Adversarial Learning Methods for Machine Learning and Data Mining, KDD2020, August 24, 2020, San Diego, CA.)

(Video of talk available here.) 

Explainability algorithms such as LIME have enabled machine learning systems to adopt transparency and fairness, which are important qualities in commercial use cases. However, recent work has shown that LIME's naive sampling strategy can be exploited by an adversary to conceal biased, harmful behavior. We propose to make LIME more robust by training a generative adversarial network to sample more realistic synthetic data which the explainer uses to generate explanations. Our experiments demonstrate that our proposed method demonstrates an increase in accuracy across three real-world datasets in detecting biased, adversarial behavior compared to vanilla LIME. This is achieved while maintaining comparable explanation quality, with up to 99.94% in top-1 accuracy in some cases.

An Empirical Route to Logical ‘Conventionalism’
(2017, In: Baltag A., Seligman J., Yamada T. (eds) Logic, Rationality, and Interaction. LORI 2017. Lecture Notes in Computer Science, vol 10455. Springer, Berlin, Heidelberg.)

The laws of classical logic are taken to be logical truths, which in turn are taken to hold objectively. However, we might question our faith in these truths: why are they true? One general approach, proposed by Putnam and more recently Dickson or Maddy, is to adopt empiricism about logic. On this view, logical truths are true because they are true of the world alone – this gives logical truths an air of objectivity. Putnam and Dickson both take logical truths to be true in virtue of the world’s structure, given by our best empirical theory, quantum mechanics. This assumes a determinate logical structure of the world given by quantum mechanics. Here, I argue that this assumption is false, and that the world’s logical structure, and hence the related ‘true’ logic, are underdetermined. This leads to what I call empirical conventionalism.

Is Logic Empirical? Logical 'Conventionalism' from an Empirical Standpoint
(2017, Aporia Vol. XVII, Recipient of the Aporia Essay Prize)

The laws of classical logic are taken to be logical truths, and logical truths are taken to objectively hold. However, we might question our faith in these truths: why are they true? One often avoided approach is logical conventionalism, because it makes the logical truths dependent on somewhat intersubjective linguistic conventions. Another approach, proposed by Putnam (1975) and more recently Dickson (2001) or Maddy (2007), is to adopt empiricism about logic. On this view, logical truths are true because they are true of the world alone – this gives logical truths an air of objectivity unlike logical conventionalism. Putnam and Dickson both take logical truths to be true in virtue of the world’s structure, and the structure of the world is to be understood to be given by our best empirical theory, quantum mechanics. As it turns out, the structure of quantum mechanics apparently makes true the laws of quantum logic, and falsifies (one half of) the distributive law, something which was taken to be a logical truth under classical logic. Empiricists take this to indicate that the distributive law was not a logical truth to begin with. However, this argument assumes that there is a single determinate structure of the world prescribed by quantum mechanics. In this essay, I argue that this assumption is false, and that the structure of the world is underdetermined in quantum mechanics. Likewise, the choice of ‘true’ logic, as given by the world’s structure, is also underdetermined. This leads to what I call empirical conventionalism: the world alone fails to determine our logical truths. We need something broadly intersubjective, and thus less than objective, to fix our choice of logic even under empiricism. An attempt to avoid one form of conventionalism has thus led us back to another.

 
 

Drafts and Works in Progress

Do Black Holes Evaporate? (First draft in the works, please contact me if interested!)

Since Hawking first predicted that black holes lose mass and ‘evaporate’ via Hawking radiation, the phenomenon has become a linchpin of black hole research. However, I argue here that there is no grounds for thinking that black hole evaporation occurs. The derivation of black hole evaporation, I claim, runs into a simple dilemma: either the black hole is not changing in time, in which case evaporation cannot occur, or the black hole is changing in time, in which case there are no suitable symmetries for the global conservation of mass-energy, and so no reason to expect evaporation as a result of Hawking radiation.

Lakatos’s analysis of growth and degeneration in the Methodology of Scientific Research Programmes (1978) is well-known. Less known, however, are his thoughts on degeneration in Proofs and Refutations (1976). Here, I propose and motivate two new criteria for degeneration based on the discussion in Proofs and Refutations – superfluity and authoritarianism. I then show how these criteria can fruitfully augment the criteria provided in the Methodology of Scientific Research Programmes, providing a generalized Lakatosian account of progress and degeneration. As a proof of concept, I employ this generalized account in evaluating a key transition point in the history of entropy – the transition to an information-theoretic interpretation of entropy – by assessing Jaynes’s 1957 paper on information theory and statistical mechanics.

Taking Relativistic Thermodynamics Too Seriously
(Coming Soon)

Despite the rampant use of thermodynamic reasoning in contemporary relativistic physics, notably black hole thermodynamics, the notion of temperature remains a controversial one in relativity. Owing to a century old debate over the appropriate definition of the Lorentz transformation for temperature, it remains uncertain whether a moving object has a hotter or colder temperature. In this paper, I argue that this situation should suggest doubt for the enterprise of relativistic thermodynamics: why should we take relativistic thermodynamics seriously?

Indeterminism for Nomological Bohmian Mechanics
(Under Revision)

Given the nomological approach to interpreting the wave-function in non-relativistic Bohmian mechanics, and box-standard notions of time-reversal invariance and indeterminism, I argue that Bohmian mechanics is indeterministic. On the one hand, (1) Bohmian particles have deterministic trajectories. On the other hand, (2) Bohmian mechanics is time-reversal invariant. However, given (3) the nomological approach { on which wave-functions are interpreted as (part of) the laws, I argue that (1) and (2) cannot be true at the same time. At least one of (1) - (3) must go. I consider and reject four options: giving up time-reversal invariance (for the theory, and `partially' for the wave-function alone), giving up deterministic trajectories, and revising our definition of determinism. In the end, I conclude that we should abandon the nomological approach instead.

Accuracy, Entropy, and the Free Energy Principle
(In Preparation)

I show that the relative entropy – also known as the Kullback-Leibler divergence (Kullback-Leibler 1951) – can be construed as a normative measure of epistemic accuracy in the veins of Joyce (1998). Furthermore, I discuss the Free Energy Principle – made popular in recent years by neuroscientist Karl Friston (cf. Friston 2007) and philosophers like Andy Clark (2016) – and how it employs a formally identical measure, though as a descriptive measure of perceptual accuracy in neural processing. I then propose that we naturalize – and provide naturalistic grounds for – the normative measure by appealing to its realization in our brain.