- Natural Kinds, Logic of Discovery, & Automated Discovery
- Philosophy of Physics
- Philosophy of Biology
- Other Philosophy
- Other Physics, Fluid Mechanics, Etc.
My current work is focused on a suite of interrelated questions about natural kinds and the logic of discovery. I am attempting to test ideas about the logic of discovery by building algorithms that carry out automated scientific discovery. In particular, I'm interested in algorithms capable of generating novel ontologies or, put less grandly, novel sets of variables that may cross-cut those provided as input. Working drafts are available for some components and derivatives of this work (I'll make more available soon). My paper arguing, contrary to received wisdom, that there must exist a logic of discovery can be found here. With regard to natural kinds, a paper in which I apply what I call the 'dynamical kinds' approach to the problem of levels of selection can be found here. A talk I gave on the same material at the International Conference on Evolutionary Patterns in Lisbon can be found here.
Permutation invariance and particle ontologies
In work on the interpretation of scientific theories of matter, I demonstrate the untenability of viewing the world in terms of particles - tiny, unobservable entities the properties of which determine the properties of observable objects. In order to be empirically accurate, modern physical theories must embrace a principle of symmetry that is demonstrably inconsistent with even the sparest notion of a particle. Though previous authors have rejected specific particle interpretations in the context of specific physical theories, this general inconsistency had gone unnoticed. A paper that lays this out can be found here. In part to demonstrate a class of alternative, consistent interpretations, I have worked out a view that treats regions of space as the objects out of which the observable world is made.
Ontic structuralism and 'non-individuals'
At the 2008 PSA Conference, I presented a paper that lays out a general challenge for the ontic structuralist. The central claim of was that relational structure is insufficient to fix the cardinality of the set of supervening objects (roughly an inversion of Newman's objection to Russell). In a paper appearing in Synthese, I argued further that in general no satisfactory notion of cardinality can be had without a relation of strict identity.
At the 2014 PSA Conference, I'll be presenting a paper that criticizes the project of explicating a notion of 'non-individuality'. Roughly, non-individuals are entities that exist in definite numbers yet fail to be identical with themselves or not identical with (at least some) other such entities. The existence of non-individuals is supposedly motivated by certain features of quantum mechanics. My critique is largely methodological. Accepting the existence of non-individuals not only forces us to abandon intuitive notions of cardinality but requires us to look for radically different theories of semantics, of how to give meaning to utterances about non-individuals. Since there are other, less destructive ways of accommodating the quantum facts in question, I urge the rejection of 'non-individuals'. A draft of the paper can be found here.
David Danks (CMU) and I collaborated in producing a formal extension of classical coding theory that provides a framework for defining codes amongst sets of biological macromolecules. The resulting definition picks out a privileged class of processes characterized by what we call ‘topological causation.’ A preprint of the paper (which appeared in the July 2008 issue of Philosophy of Science) can be found here.
Quantum indeterminism and micro-evolution
Despite frequent pronouncements to the contrary, quantum indeterminism must significantly impact processes at the molecular and, in biological systems, macroscopic scales. In recent work, I have been able show the minimum extent to which two biological processes - chromosome segregation and sperm binding at the zon pellcuida - are rendered indeterministic by quantum indeterminism at the level of chemical bonds. This work was presented at the 2009 ISHPSSB meeting in Brisbane, Australia. I'm currently drafting a paper that presents these results in detail.
My book on design arguments for the existence of God was published in 2014. The book is a critical survey of two millennia of design arguments.
Historical inference and judgment aggregation
C. S. Peirce, in a few largely overlooked manuscripts, offers a strong argument against the Bayesian approach to historical inference. His argument is cast as a rebuttal to Hume’s famous “On Miracles,” but has far-reaching implications for theories of judgment aggregation and historical inference. In an article appearing in the Transactions of the Charles S. Peirce Society, I reconstruct Peirce’s argument and draw out some of these implications. That paper may be found here. In a contribution to the volume, Probability in the Philosophy of Religion, I further develop the general critique of Bayesian inference inspired by Peirce.
Development of probability theory
A unified theory of probability emerged rather abruptly amidst the Enlightenment, motivated by diverse conceptions of the probable and without a unified account of what the theory describes. As the recipient of a competitive Posner Center Internship, I developed a conceptual history of the emergence of probability.
Using optical tweezers technology, the individual strands of a single DNA molecule can be pulled apart, with the applied forces measured to an accuracy on the order of a pico-Newton. I was part of the team at Cornell under Michelle Wang’s leadership that adapted this technology to spatially locate DNA-protein interactions with high-resolution. Our paper on this method can be found here.
Pursuing an idea advanced by Thomas Eisner of Cornell University, I constructed a system for tracking butterflies in three dimensions during free flight. We were able to show that, while butterflies are able to fly without their hindwings (an amazing fact considering these comprise roughly 50% of total wing area), they cannot maintain the high turning accelerations that characterize their typical ‘erratic’ flight. An abstract and full text of the paper can be found here: Hindwings are unnecessary for flight but essential for execution of normal evasive flight in Lepidoptera. Popular accounts of the paper are available from the BBC (radio, science blog) and American Scientist (article).
In a research program I ran at the Naval Undersea Warfare Center, we demonstrated in tow tank tests with scale models that the surface signatures of submarine masts can be dramatically influenced by planform shape. For details, see:
Jantzen, B. C. and C. W. Henoch. A Full-Scale Investigation of the Wake Produced By Surface-Piercing Masts: Baseline Measurements and Verification of Technique. NUWC-NPT Technical Memo 03-129.
Jantzen, B. C. and M. Genco. A Towing Tank Investigation of Production of White-water Wake By Surface-piercing Masts. NUWC-NPT Technical Memo 02-122.
Multi-criteria decision analysis
In work with Bill Krol (NUWC), in conjunction with his UWDO project, I developed a fast, novel algorithm for analyzing decisions in which multiple criteria are in play but can be ranked only qualitatively relative to one another.