Surface Tension: Conceptual Challenges in Modeling Nanoscale Material Surfaces

All solid and liquid materials have surfaces, and surfaces typically exhibit different physical and chemical properties and behaviors than the bulk or interior of the materials they contain. The properties and behaviors of surfaces are, thus, a universal feature of materials and a perennial object of study in the physical sciences. One important way in which this study manifests is in the modeling of materials. Contemporary philosophy of science has taken a strong interest in the epistemology of scientific modeling, and recently, particular attention has been given to the conceptual, epistemic, ontological, and practical challenges posed by multiscale modeling. Representing surface properties and behaviors within a wider context of material behavior is often a goal of constructing multiscale models of materials. Despite this, and despite that much philosophical literature on multiscale modeling addresses models in physics, little has so far been said about the challenges associated with modeling material surfaces. Further, nanoscale materials present a variety of practical, theoretical, and conceptual challenges for traditional approaches to modeling the physical and chemical behavior of materials. In this article, I examine how two distinct approaches to modeling surfaces arise from two distinct conceptions of what a surface is. I call these the "boundary on a body" conception and the "outermost layer" conception, and I show how the distinction both underwrites different modeling strategies and threatens reductive approaches to the epistemology of modeling

Surface Tension: Conceptual Challenges in Modeling Nanoscale Material Surfaces

All solid and liquid materials have surfaces, and surfaces typically exhibit different physical and chemical properties and behaviors than the bulk or interior of the materials they contain. The properties and behaviors of surfaces are, thus, a universal feature of materials and a perennial object of study in the physical sciences. One important way in which this study manifests is in the modeling of materials. Contemporary philosophy of science has taken a strong interest in the epistemology of scientific modeling, and recently, particular attention has been given to the conceptual, epistemic, ontological, and practical challenges posed by multiscale modeling. Representing surface properties and behaviors within a wider context of material behavior is often a goal of constructing multiscale models of materials. Despite this, and despite that much philosophical literature on multiscale modeling addresses models in physics, little has so far been said about the challenges associated with modeling material surfaces. Further, nanoscale materials present a variety of practical, theoretical, and conceptual challenges for traditional approaches to modeling the physical and chemical behavior of materials. In this article, I examine how two distinct approaches to modeling surfaces arise from two distinct conceptions of what a surface is. I call these the "boundary on a body" conception and the "outermost layer" conception, and I show how the distinction both underwrites different modeling strategies and threatens reductive approaches to the epistemology of modeling

The Function of Boundary Conditions in the Physical Sciences

Early philosophical accounts of explanation mistook the function of boundary conditions for that of contingent facts. I diagnose where this misunderstanding arose and establish that it persists. I disambiguate between uses of the term "boundary conditions" and argue that boundary conditions are explanatory via their roles as components of models. Using case studies from fluid mechanics and the physics of waves, I articulate four explanatory functions for boundary conditions in physics: specifying the scope of a model, enabling stable descriptions of phenomena in the model, generating descriptions of novel phenomena, and connecting models from differing theoretical backgrounds

The Function of Boundary Conditions in the Physical Sciences

Early philosophical accounts of explanation mistook the function of boundary conditions for that of contingent facts. I diagnose where this misunderstanding arose and establish that it persists. I disambiguate between uses of the term "boundary conditions" and argue that boundary conditions are explanatory via their roles as components of models. Using case studies from fluid mechanics and the physics of waves, I articulate four explanatory functions for boundary conditions in physics: specifying the scope of a model, enabling stable descriptions of phenomena in the model, generating descriptions of novel phenomena, and connecting models from differing theoretical backgrounds

Multiscale Modeling in Nanoscience: Beyond Hierarchical Relations

Winsberg's "handshaking" account of inter-model relations is a well-known theory of multiscale modeling in physical systems. Winsberg argues that relations among the component models in a multiscale modeling system are not related mereologically, but rather by empirically determined algorithms. I argue that while the handshaking account does demonstrate the existence of non-mereological relationships among component models, Winsberg does not attend to the different ways in which handshaking algorithms are developed. By overlooking the distinct strategies employed in different handshake models, Winsberg's account fails to capture the central feature of effective multiscale modeling practices, namely, how the dominant behaviors of the modeled systems vary across the different scales, and how this variation constrains the ways modelers can combine component models. Using Winsberg's example of nanoscale crack propagation, I distinguish two modes of handshaking and show how the different modes arise from the scale-dependent physics involved in each component model

Good Fortune and Hard Work

Commencement address given by Bruce E. Bursten, Professor in the Department of Chemistry at The Ohio State University, to the Winter 1998 graduating class of The Ohio State University, St. John Arena, Columbus, Ohio, March 20, 1998

Promoting Cognitive Conflict in Health Care Ethics: Moral Reasoning with Boundary Cases

As many college students are at a time of tremendous personal and academic growth, introductory philosophy courses have the potential to equip students with practical critical reasoning skills. Despite this, many introductory courses in this domain emphasize students’ learning about pre-existing dialectics in the abstract, rather than over self-reflection and development of personal philosophical perspectives. In doing so, we may be failing to support the needs of pre-professional students looking to prepare themselves for their careers ahead. In this practitioner paper, we report our efforts as a practicing philosophy instructor (Bursten) and a learning scientist (Finkelstein) to iterate on the design of a student-centered instrument for moral reasoning in medical contexts within an introductory Health Care Ethics course. We identified the positive role that providing boundary cases played in helping students’ experience productive cognitive conflict, and, in turn, how these experiences improved critical self-reflection and moral reasoning

The Function of Boundary Conditions in the Physical Sciences

Early philosophical accounts of explanation mistook the function of boundary conditions for that of contingent facts. I diagnose where this misunderstanding arose and establish that it persists. I disambiguate between two uses of the term “boundary conditions” and argue that boundary conditions are explanatory via their roles as components of models. Using case studies from fluid mechanics and the physics of waves, I articulate four explanatory functions for boundary conditions in physics: specifying the scope of a model, enabling stable descriptions of phenomena in a model, generating descriptions of novel phenomena, and connecting models from differing theoretical backgrounds