Roman Frigg
Datos Biográficos
| ID | 461344 |
|---|---|
| NOMBRE | Roman Frigg |
| NOMBRES | Roman |
| APELLIDO | Frigg |
| FIRMA | FRIGG R |
| AFILIACIONES | London School of Economics and Political Science |
| ORCID | 0000-0003-0812-0907 |
| VERIFICADO | Sí |
| TOTAL DE OBRAS | 35 |
| TOTAL DE CITAS | 215 |
| TOTAL COMO AUTOR | 34 |
| TOTAL COMO EDITOR | 1 |
| PRIMER AÑO DE PUBLICACIÓN | 2003 |
| AÑO MÁS RECIENTE DE PUBLICACIÓN | 2025 |
| ÍNDICE H | 8 |
Proofs and Research Programmes
This open access book offers new insights into issues raised in philosophy of mathematics and in philosophy of science by Imre Lakatos.
Stabilising understanding
We present an account of how idealised models provide scientific understanding that is based on the notion of stability: a model provides understanding of a target behaviour when both the model and the target’s perfect model are in a class of models over which that behaviour is stable. The class is characterised in terms of what we call the model’s noetic core, which contains the features that are indispensable to both the model’s and the target’…
Reconsidering Representation
Models and Theories
Models and theories are of central importance in science, and scientists spend substantial amounts of time building, testing, comparing and revising models and theories. It is therefore not surprising that the nature of scientific models and theories has been a widely debated topic within the philosophy of science for many years. The product of two decades of research, this book provides an accessible yet critical introduction to the debates abou…
Mirrors without warnings
Veritism, the position that truth is necessary for epistemic acceptability, seems to be in tension with the observation that much of our best science is not, strictly speaking, true when interpreted literally. This generates a paradox: (1) truth is necessary for epistemic acceptability; (2) the claims of science have to be taken literally; (3) much of what science produces is not literally true and yet it is acceptable. We frame Elgin’s project i…
Mathematics is not the only language in the book of nature
Making Confident Decisions with Model Ensembles
Many policy decisions take input from collections of scientific models. Such decisions face significant and often poorly understood uncertainty. We rework the so-called confidence approach to tackle decision-making under severe uncertainty with multiple models, and we illustrate the approach with a case study: insurance pricing using hurricane models. The confidence approach has important consequences for this case and offers a powerful framework…
Can Somebody Please Say What Gibbsian Statistical Mechanics Says
Gibbsian statistical mechanics (GSM) is the most widely used version of statistical mechanics among working physicists. Yet a closer look at GSM reveals that it is unclear what the theory actually says and how it bears on experimental practice. The root cause of the difficulties is the status of the averaging principle, the proposition that what we observe in an experiment is the ensemble average of a phase function. We review different stances t…
When do Gibbsian phase averages and Boltzmannian equilibrium values agree
Mind the Gap
There are two main theoretical frameworks in statistical mechanics, one associated with Boltzmann and the other with Gibbs. Despite their well-known differences, there is a prevailing view that equilibrium values calculated in both frameworks coincide. We show that this is wrong. There are important cases in which the Boltzmannian and Gibbsian equilibrium concepts yield different outcomes. Furthermore, the conditions under which equilibriums exis…
Expert Judgment for Climate Change Adaptation
Climate change adaptation is largely a local matter, and adaptation planning can benefit from local climate change projections. Such projections are typically generated by accepting climate model outputs in a relatively uncritical way. We argue, based on the IPCC’s treatment of model outputs from the CMIP5 ensemble, that this approach is unwarranted and that subjective expert judgment should play a central role in the provision of local climate c…
Reconceptualising equilibrium in Boltzmannian statistical mechanics and characterising its existence
An assessment of the foundational assumptions in high-resolution climate projections
Rethinking Boltzmannian Equilibrium
Boltzmannian statistical mechanics partitions the phase space of a system into macroregions, and the largest of these is identified with equilibrium. What justifies this identification? Common answers focus on Boltzmann’s combinatorial argument, the Maxwell-Boltzmann distribution, and maximum entropy considerations. We argue that they fail and present a new answer. We characterize equilibrium as the macrostate in which a system spends most of its…
Philosophy of Climate Science Part II
This is the second of three parts of an introduction to the philosophy of climate science. In this second part about modelling climate change, the topics of climate modelling, confirmation of climate models, the limits of climate projections, uncertainty and finally model ensembles will be discussed
Philosophy of Climate Science Part I
This is the first of three parts of an introduction to the philosophy of climate science. In this first part about observing climate change, the topics of definitions of climate and climate change, data sets and data models, detection of climate change, and attribution of climate change will be discussed
Laplace’s Demon and the Adventures of His Apprentices
The sensitive dependence on initial conditions (SDIC) associated with nonlinear models imposes limitations on the models’ predictive power. We draw attention to an additional limitation than has been underappreciated, namely, structural model error (SME). A model has SME if the model dynamics differ from the dynamics in the target system. If a nonlinear model has only the slightest SME, then its ability to generate decision-relevant predictions i…
Clever Fetishists
Anthropologist Arjun Appadurai has coined the phrase ‘methodological fetishism’ to denote tactics of thinking with objects.[1] Fetishisms tend to attract a following, and methodological fetishism is no exception. Mexican textiles, unbreakable glasses, folding screens, Victorian tapestries, telescopic micrometers and stilettos strung together to form a wheel – the contributions to this volume are testimony to art history’s amour with objects. But …
The Myopia of Imperfect Climate Models
The United Kingdom Climate Impacts Program’s UKCP09 project makes high-resolution forecasts of climate during the twenty-first century using state of the art global climate models. The aim of this article is to introduce and analyze the methodology used and then urge some caution. Given the acknowledged systematic errors in all current climate models, treating model outputs as decision-relevant probabilistic forecasts can be seriously misleading.…
Demystifying Typicality
A gas prepared in a nonequilibrium state will approach equilibrium and stay there. An influential contemporary approach to statistical mechanics explains this behavior in terms of typicality. However, this explanation has been criticized as mysterious as long as no connection with the dynamics of the system is established. We take this criticism as our point of departure. Our central claim is that Hamiltonians of gases that are epsilon-ergodic ar…
Confirmation and reduction
Various scientific theories stand in a reductive relation to each other. In a recent article, we have argued that a generalized version of the Nagel-Schaffner model (GNS) is the right account of this relation. In this article, we present a Bayesian analysis of how GNS impacts on confirmation. We formalize the relation between the reducing and the reduced theory before and after the reduction using Bayesian networks, and thereby show that, post-re…
The philosophy of simulation
Explaining Thermodynamic-Like Behavior in Terms of Epsilon-Ergodicity
Why do gases reach equilibrium when left to themselves? The canonical answer, originally proffered by Boltzmann, is that the systems have to be ergodic. This answer is now widely regarded as flawed. We argue that some of the main objections in particular arguments based on the Kolmogorov-Arnold-Moser theorem and the Markus-Meyer theorem are beside the point. We then argue that something close to Boltzmann’s proposal is true: gases behave thermody…
Who’s Afraid of Nagelian Reduction?
We reconsider the Nagelian theory of reduction and argue that, contrary to a widely held view, it is the right analysis of intertheoretic reduction. The alleged difficulties of the theory either vanish upon closer inspection or turn out to be substantive philosophical questions rather than knock-down arguments.
Fiction in Science
Models and fiction
Typicality and the Approach to Equilibrium in Boltzmannian Statistical Mechanics
An important contemporary version of Boltzmannian statistical mechanics explains the approach to equilibrium in terms of typicality. The problem with this approach is that it comes in different versions, which are, however, not recognized as such and not clearly distinguished. This article identifies three different versions of typicality-based explanations of thermodynamic-like behavior and evaluates their respective successes. The conclusion is…
The philosophy of simulation
Laplace’s Demon and the Adventures of His Apprentices
The sensitive dependence on initial conditions (SDIC) associated with nonlinear models imposes limitations on the models’ predictive power. We draw attention to an additional limitation than has been underappreciated, namely, structural model error (SME). A model has SME if the model dynamics differ from the dynamics in the target system. If a nonlinear model has only the slightest SME, then its ability to generate decision-relevant predictions i…
The Myopia of Imperfect Climate Models
The United Kingdom Climate Impacts Program’s UKCP09 project makes high-resolution forecasts of climate during the twenty-first century using state of the art global climate models. The aim of this article is to introduce and analyze the methodology used and then urge some caution. Given the acknowledged systematic errors in all current climate models, treating model outputs as decision-relevant probabilistic forecasts can be seriously misleading.…
An assessment of the foundational assumptions in high-resolution climate projections
Demystifying Typicality
A gas prepared in a nonequilibrium state will approach equilibrium and stay there. An influential contemporary approach to statistical mechanics explains this behavior in terms of typicality. However, this explanation has been criticized as mysterious as long as no connection with the dynamics of the system is established. We take this criticism as our point of departure. Our central claim is that Hamiltonians of gases that are epsilon-ergodic ar…
Rethinking Boltzmannian Equilibrium
Boltzmannian statistical mechanics partitions the phase space of a system into macroregions, and the largest of these is identified with equilibrium. What justifies this identification? Common answers focus on Boltzmann’s combinatorial argument, the Maxwell-Boltzmann distribution, and maximum entropy considerations. We argue that they fail and present a new answer. We characterize equilibrium as the macrostate in which a system spends most of its…
Self-organised criticality—what it is and what it isn’t
Models and Theories
Models and theories are of central importance in science, and scientists spend substantial amounts of time building, testing, comparing and revising models and theories. It is therefore not surprising that the nature of scientific models and theories has been a widely debated topic within the philosophy of science for many years. The product of two decades of research, this book provides an accessible yet critical introduction to the debates abou…
Mirrors without warnings
Veritism, the position that truth is necessary for epistemic acceptability, seems to be in tension with the observation that much of our best science is not, strictly speaking, true when interpreted literally. This generates a paradox: (1) truth is necessary for epistemic acceptability; (2) the claims of science have to be taken literally; (3) much of what science produces is not literally true and yet it is acceptable. We frame Elgin’s project i…
Expert Judgment for Climate Change Adaptation
Climate change adaptation is largely a local matter, and adaptation planning can benefit from local climate change projections. Such projections are typically generated by accepting climate model outputs in a relatively uncritical way. We argue, based on the IPCC’s treatment of model outputs from the CMIP5 ensemble, that this approach is unwarranted and that subjective expert judgment should play a central role in the provision of local climate c…
Confirmation and reduction
Various scientific theories stand in a reductive relation to each other. In a recent article, we have argued that a generalized version of the Nagel-Schaffner model (GNS) is the right account of this relation. In this article, we present a Bayesian analysis of how GNS impacts on confirmation. We formalize the relation between the reducing and the reduced theory before and after the reduction using Bayesian networks, and thereby show that, post-re…
Mathematics is not the only language in the book of nature
Philosophy of Climate Science Part II
This is the second of three parts of an introduction to the philosophy of climate science. In this second part about modelling climate change, the topics of climate modelling, confirmation of climate models, the limits of climate projections, uncertainty and finally model ensembles will be discussed
Explaining Thermodynamic-Like Behavior in Terms of Epsilon-Ergodicity
Why do gases reach equilibrium when left to themselves? The canonical answer, originally proffered by Boltzmann, is that the systems have to be ergodic. This answer is now widely regarded as flawed. We argue that some of the main objections in particular arguments based on the Kolmogorov-Arnold-Moser theorem and the Markus-Meyer theorem are beside the point. We then argue that something close to Boltzmann’s proposal is true: gases behave thermody…
Chance in Boltzmannian Statistical Mechanics
In two recent papers Barry Loewer (2001, 2004) has suggested to interpret probabilities in statistical mechanics as chances in David Lewis's (1994) sense. I first give a precise formulation of this proposal, then raise two fundamental objections, and finally conclude that these can be overcome only at the price of interpreting these probabilities epistemically
Can Somebody Please Say What Gibbsian Statistical Mechanics Says
Gibbsian statistical mechanics (GSM) is the most widely used version of statistical mechanics among working physicists. Yet a closer look at GSM reveals that it is unclear what the theory actually says and how it bears on experimental practice. The root cause of the difficulties is the status of the averaging principle, the proposition that what we observe in an experiment is the ensemble average of a phase function. We review different stances t…
Philosophy of Climate Science Part I
This is the first of three parts of an introduction to the philosophy of climate science. In this first part about observing climate change, the topics of definitions of climate and climate change, data sets and data models, detection of climate change, and attribution of climate change will be discussed
Making Confident Decisions with Model Ensembles
Many policy decisions take input from collections of scientific models. Such decisions face significant and often poorly understood uncertainty. We rework the so-called confidence approach to tackle decision-making under severe uncertainty with multiple models, and we illustrate the approach with a case study: insurance pricing using hurricane models. The confidence approach has important consequences for this case and offers a powerful framework…
Mind the Gap
There are two main theoretical frameworks in statistical mechanics, one associated with Boltzmann and the other with Gibbs. Despite their well-known differences, there is a prevailing view that equilibrium values calculated in both frameworks coincide. We show that this is wrong. There are important cases in which the Boltzmannian and Gibbsian equilibrium concepts yield different outcomes. Furthermore, the conditions under which equilibriums exis…
The Images of Time. An Essay on Temporal Representation
WE experience time in different ways, and we construct different kinds of representation of time. What kinds of representation are there and how do they work? In particular, how do we integrate temporal features of the world into our understanding of the mechanisms underlying representations in the media of perception, memory, art, and narrative? Le Poidevin's well-written and carefully argued book is an exploration of these questions. Although i…
In What Sense is the Kolmogorov-Sinai Entropy a Measure for Chaotic Behaviour?—Bridging the Gap Between Dynamical Systems Theory and Communication Theory
On an influential account, chaos is explained in terms of random behaviour; and random behaviour in turn is explained in terms of having positive Kolmogorov-Sinai entropy (KSE). Though intuitively plausible, the association of the KSE with random behaviour needs justification since the definition of the KSE does not make reference to any notion that is connected to randomness. I provide this justification for the case of Hamiltonian systems by pr…
Self-organised criticality—what it is and what it isn’t
In What Sense is the Kolmogorov-Sinai Entropy a Measure for Chaotic Behaviour?—Bridging the Gap Between Dynamical Systems Theory and Communication Theory
On an influential account, chaos is explained in terms of random behaviour; and random behaviour in turn is explained in terms of having positive Kolmogorov-Sinai entropy (KSE). Though intuitively plausible, the association of the KSE with random behaviour needs justification since the definition of the KSE does not make reference to any notion that is connected to randomness. I provide this justification for the case of Hamiltonian systems by pr…
The ergodic hierarchy, randomness and Hamiltonian chaos
Probability in GRW theory
Chance in Boltzmannian Statistical Mechanics
In two recent papers Barry Loewer (2001, 2004) has suggested to interpret probabilities in statistical mechanics as chances in David Lewis's (1994) sense. I first give a precise formulation of this proposal, then raise two fundamental objections, and finally conclude that these can be overcome only at the price of interpreting these probabilities epistemically
The Images of Time. An Essay on Temporal Representation
WE experience time in different ways, and we construct different kinds of representation of time. What kinds of representation are there and how do they work? In particular, how do we integrate temporal features of the world into our understanding of the mechanisms underlying representations in the media of perception, memory, art, and narrative? Le Poidevin's well-written and carefully argued book is an exploration of these questions. Although i…
A Companionable Coverage of the Philosophy of Science
The philosophy of simulation
Typicality and the Approach to Equilibrium in Boltzmannian Statistical Mechanics
An important contemporary version of Boltzmannian statistical mechanics explains the approach to equilibrium in terms of typicality. The problem with this approach is that it comes in different versions, which are, however, not recognized as such and not clearly distinguished. This article identifies three different versions of typicality-based explanations of thermodynamic-like behavior and evaluates their respective successes. The conclusion is…
Who’s Afraid of Nagelian Reduction?
We reconsider the Nagelian theory of reduction and argue that, contrary to a widely held view, it is the right analysis of intertheoretic reduction. The alleged difficulties of the theory either vanish upon closer inspection or turn out to be substantive philosophical questions rather than knock-down arguments.
Fiction in Science
Models and fiction
Confirmation and reduction
Various scientific theories stand in a reductive relation to each other. In a recent article, we have argued that a generalized version of the Nagel-Schaffner model (GNS) is the right account of this relation. In this article, we present a Bayesian analysis of how GNS impacts on confirmation. We formalize the relation between the reducing and the reduced theory before and after the reduction using Bayesian networks, and thereby show that, post-re…
The philosophy of simulation
Explaining Thermodynamic-Like Behavior in Terms of Epsilon-Ergodicity
Why do gases reach equilibrium when left to themselves? The canonical answer, originally proffered by Boltzmann, is that the systems have to be ergodic. This answer is now widely regarded as flawed. We argue that some of the main objections in particular arguments based on the Kolmogorov-Arnold-Moser theorem and the Markus-Meyer theorem are beside the point. We then argue that something close to Boltzmann’s proposal is true: gases behave thermody…
Demystifying Typicality
A gas prepared in a nonequilibrium state will approach equilibrium and stay there. An influential contemporary approach to statistical mechanics explains this behavior in terms of typicality. However, this explanation has been criticized as mysterious as long as no connection with the dynamics of the system is established. We take this criticism as our point of departure. Our central claim is that Hamiltonians of gases that are epsilon-ergodic ar…
Clever Fetishists
Anthropologist Arjun Appadurai has coined the phrase ‘methodological fetishism’ to denote tactics of thinking with objects.[1] Fetishisms tend to attract a following, and methodological fetishism is no exception. Mexican textiles, unbreakable glasses, folding screens, Victorian tapestries, telescopic micrometers and stilettos strung together to form a wheel – the contributions to this volume are testimony to art history’s amour with objects. But …
The Myopia of Imperfect Climate Models
The United Kingdom Climate Impacts Program’s UKCP09 project makes high-resolution forecasts of climate during the twenty-first century using state of the art global climate models. The aim of this article is to introduce and analyze the methodology used and then urge some caution. Given the acknowledged systematic errors in all current climate models, treating model outputs as decision-relevant probabilistic forecasts can be seriously misleading.…
Laplace’s Demon and the Adventures of His Apprentices
The sensitive dependence on initial conditions (SDIC) associated with nonlinear models imposes limitations on the models’ predictive power. We draw attention to an additional limitation than has been underappreciated, namely, structural model error (SME). A model has SME if the model dynamics differ from the dynamics in the target system. If a nonlinear model has only the slightest SME, then its ability to generate decision-relevant predictions i…
Reconceptualising equilibrium in Boltzmannian statistical mechanics and characterising its existence
An assessment of the foundational assumptions in high-resolution climate projections
Rethinking Boltzmannian Equilibrium
Boltzmannian statistical mechanics partitions the phase space of a system into macroregions, and the largest of these is identified with equilibrium. What justifies this identification? Common answers focus on Boltzmann’s combinatorial argument, the Maxwell-Boltzmann distribution, and maximum entropy considerations. We argue that they fail and present a new answer. We characterize equilibrium as the macrostate in which a system spends most of its…
Philosophy of Climate Science Part II
This is the second of three parts of an introduction to the philosophy of climate science. In this second part about modelling climate change, the topics of climate modelling, confirmation of climate models, the limits of climate projections, uncertainty and finally model ensembles will be discussed
Philosophy of Climate Science Part I
This is the first of three parts of an introduction to the philosophy of climate science. In this first part about observing climate change, the topics of definitions of climate and climate change, data sets and data models, detection of climate change, and attribution of climate change will be discussed
Expert Judgment for Climate Change Adaptation
Climate change adaptation is largely a local matter, and adaptation planning can benefit from local climate change projections. Such projections are typically generated by accepting climate model outputs in a relatively uncritical way. We argue, based on the IPCC’s treatment of model outputs from the CMIP5 ensemble, that this approach is unwarranted and that subjective expert judgment should play a central role in the provision of local climate c…
Computer Science (28 obras) · Philosophy (22 obras) · Epistemology (21 obras) · Mathematics (20 obras) · Physics (14 obras) · Statistical physics (12 obras) · Philosophy and History of Science (11 obras) · Mathematical economics (10 obras) · Philosophy of science (10 obras) · Statistical Mechanics and Entropy (10 obras)