Research

Roughly speaking, there are two approaches in Philosophy of Physics: using philosophical methods to elucidate physics, and using physics to shed light on `traditional’ philosophical themes (such as from the philosophy of science and metaphysics). My work on reasoning in physics really goes both ways; it thus aspires to be of interest to both the philosopher of physics who works in the first sense (and the physicist) just as well as to the philosopher of science. My work on the foundations of classical spacetime theories falls largely into the first kind of approach; my work on the nature of space and time, and on the laws of nature largely into the second kind of approach.

I. Reasoning in physics
  • … in the context of theory construction: analogue reasoning, robustness analysis, physics-specific heuristics of theory construction (quantisation, semi-classical extrapolations).
  • … in the context of theory confirmation: analogue confirmation (analogue experiments), table top testing; anthropic reasoning.
  • … in `theory-free’ contexts: Fermi problems.
II. Foundations of classical spacetime theories 
  • Axiomatisation of general relativity and neighbouring spacetime theories
  • Conventional wisdoms (nature of light propagation in general relativity, status of gravitational waves in non-relativistic scenarios, ….)
  • Alternative readings and interpretations of general relativity (as a spin-2 theory, as a thermo-/hydrodynamic theory, …)
  • Intertheory relation between general relativity and special relativity (including equivalence principles)
  • Approaches to modeling black hole formation
III. Nature of space and time
  • Dynamical and functionalist accounts of spacetime
  • Status of space and time in quantum gravity
IV. Laws of nature
  • Symmetry-conservation law debates (also in the context of the Noether theorems)
  • Laws of nature of different modal strengths
  • Meta-laws

Alphabetical list of research interests

  • Analogical reasoning and confirmation (2.4, 2.7; 3.1)
  • Axiomatisation (1.2)
  • Epistemology of spacetime (1.2; 2.5, 2.16)
  • Generative strategies in theory construction (2.4, 3.1)
  • Laws of nature (2.20, 2.14, 2.12, 2.8)
  • Metaphysical necessity (2.8, 2.12, 2.14)
  • Non-empirical confirmation (2.4, 2.7, 2.11)
  • Principles in theory construction (2.4, 2.3, 2.10)
  • Renormalisability and UV completion (2.2, 2.3)
  • Spacetime emergence (2.4, 2.6, 2.9; 4.1)
  • Spacetime functionalism (2.9; 4.1)
  • Superluminal signal propagation (2.16)
  • Symmetries and conservation laws (2.8; 3.2)
  • Toy models (2.1)
  • Quantum Gravity phenomenology (1.1, 2.7)

Numbers in parentheses refer to articles listed below. For citing articles, see my google research profile.

Publications

(1) Books

1.2 Adlam, Emily; Linnemann, Niels & Read, James: Constructive Axiomatics for Spacetime Physics. Oxford University Press, Forthcoming.

1.1 Huggett, Nick; Linnemann, Niels & Schneider, Mike: Quantum Gravity in a Laboratory? Cambridge Elements. (2023). Preprint.

(2) In peer-reviewed journals

2.25 Linnemann, Niels; Azhar, Feraz: Better permissible guesses. Philosophy and Phenomenological
Research (2024). Preprint.

2.24 Azhar, Feraz; Linnemann, Niels: Rethinking the Anthropic Princiiple. Philosophy of Science (Forthcoming). Preprint.

2.23 Jaksland, Rasmus; Linnemann, Niels:  On the non-identity causal theory of spacetime from causal set theory. Erkenntnis (Forthcoming). Link to paper (open access).

2.22 Linnemann, Niels; Read, James; & Teh, Nicholas: The local validity of special relativity from a scale-relative perspective. BJPS (Forthcoming). Preprint.

2.21 Asenjo, Felipe; Hojman, Sergio; Linnemann, Niels; & Read, James: Abnormal light propagation and the underdetermination of theory by evidence in astrophysics. Annals of Physics (2024). Preprint.

2.20 Hirèche, Salim; Linnemann, Niels; & Michels, Robert: Are All Laws of Nature Created Equal? Meta-laws Versus More Necessary Laws. Erkenntnis (2023). Link to paper (open access).

2.19 Linnemann, Niels; Smeenk, Chris & Baker, Mark Robert: GR as a classical spin-2 theory? Philosophy of Science (PSA proceedings 2022). (2023). Preprint.

2.18 Dewar, Neil; Linnemann, Niels; Read, James: The epistemology of spacetime. Philosophy Compass (2022). Link to paper (open access).

2.17 Linnemann, Niels: Quantisation as a method of generation: the nature and prospects of theory changes through quantisation. Studies of History and Philosophy of Science (2022). Link to paper.

2.16 Linnemann, Niels; Read, James: Comment on `Do eletromagnetic waves move along null geodesics?‘. Classical and Quantum Gravity (2022). Preprint.

2.15 Linnemann, Read: Miracles persist – A reply to Sus. European Journal for the Philosophy of Science (2021). Link to paper (open access).

2.14 Hirèche, Salim; Linnemann, Niels; Michels, Robert & Vogt, Lisa: The Strong Arm of the Law. A Unified Account of Necessary and Contingent Laws of Nature. Synthese (2021). Link to paper (open access).

2.13 Linnemann, Niels; Read, James: On the status of Newtonian gravitational radiation. Foundations of Physics (2021). Link to paper (open access).

2.12 Hirèche, Salim; Linnemann, Niels; Michels, Robert & Vogt, Lisa: The modal status of the laws of nature. Tahko’s hybrid view and the kinematical/dynamical distinction. European Journal for the Philosophy of Science (2021). Link to paper (open access).

2.11 Linnemann, Niels: Non-empirical robustness arguments in quantum gravity. Studies of History and Philosophy of Modern Physics (2020). Link to paper (open access).

2.10 Jaksland, Rasmus & Linnemann, Niels: Holography without holography: How to turn inter-representational into intra-representational relations in AdS/CFT. Studies of History and Philosophy of Modern Physics (2020). Link to paper (open access).

2.9 Linnemann, Niels: On the empirical coherence and the spatiotemporal gap problem in quantum gravity — and why functionalism does not (have to) help. Synthese: SI Spacetime Functionalism (2020). Link to paper (open access).

2.8 Linnemann, Niels: On metaphysically necessary laws from physics. European Journal for the Philosophy of Science (2020). Link to paper (open access).

2.7 Crowther, Karen; Linnemann, Niels & Wüthrich, Christian: What we cannot learn from analogue experiments. Synthese: Special Issue: Reasoning in Physics (2019). Preprint.

2.6 Le Bihan, Baptiste & Linnemann, Niels: Have We Lost Spacetime on the Way? Narrowing the Gap Between General Relativity and Quantum Gravity. Studies of History and Philosophy of Modern Physics (2019). Preprint.

2.5 Menon, Tushar; Linnemann, Niels & Read, James: Clocks and Chronogeometry: Rotating spacetimes and the relativistic null hypothesis. The British Journal for the Philosophy of Science (2018). Preprint.

2.4 Linnemann, Niels & Visser, Manus: Hints toward the emergent nature of gravity. Studies of History and Philosophy of Modern Physics (2018). Preprint.

2.3 Doboszewski, Juliusz & Linnemann, Niels: How not to establish the non-renormalizability of gravity. Foundations of Physics (2017): 1-16. Preprint.

2.2 Crowther, Karen & Linnemann, Niels: Renormalizability, fundamentality, and a final theory: The role of UV-completion in the search for quantum gravity. The British Journal for the Philosophy of Science (2017). Preprint.

2.1 Irbäck, Anders; Jonsson, Sigurdur; Linnemann, Niels; Linse, Björn; Wallin, Stefan: Aggregate geometry in amyloid fibril nucleation. Physical Review Letters (2013). Paper.

(3) In edited volumes

3.2 Baker, Mark; Linnemann, Niels and Smeenk, Chris: Noether’s first theorem and the energy-momentum tensor ambiguity problem, in: Teh, Nicholas; Read, James and Roberts, Bryan, editors: The Physics and Philosophy of Noether’s Theorems. Cambridge University Press. (2022). Preprint.

3.1 Linnemann, Niels: Interpretations of GR as guidelines for theory change, in Beisbart,  Claus; Sauer, Tilman Sauer; Wüthrich,  Christian; editors: Thinking About Space and Time: 100 Years of Applying and Interpreting General Relativity. Birkhäuser (Basel) (2020). Preprint.

(4) Edited issues

4.1 Crowther, Karen, Linnemann, Niels, & Wüthrich, Christian, editors: Special Issue on Spacetime Functionalism (Synthese). Springer (2021). Introduction (open access).

(5) Invited Reviews

5.1 Linnemann, Niels: Book review of Andreas Bartels’ `Wissenschaft’ (De Gruyter, 2021). Journal for General Philosophy of Science (2023).

Relevant preprints

On the trade-off conception in Humeanism (with Robert Michels): https://philsci-archive.pitt.edu/23200/

On pregeometry (with Kian Salimkhani): http://philsci-archive.pitt.edu/20035/1/Linnemann-Salimkhani-Pregeometry.pdf

Selected Talks

9/2024 Invited talk: Rethinking the Anthropic Principle (joint work with Feraz Azhar). (Carl Friedrich von Weizsäcker Kolloquium, University of Tübingen).

9/2023 Invited talk: Can AI help Humeans? The laws of nature debate in light of automated scientific discovery (joint work with Robert Michels) (HPS Seminar, University of Copenhagen).

7/2023 Invited talk:  The local validity of special relativity from an EFT-inspired perspective (joint work with James Read and Nicholas Teh) (Workshop on Foundations of Physics, University of Oxford).

7/2023 Contributed talk:  What makes black hole models physically reasonable?  (joint work with Yichen Luo and Chris Smeenk) (Foundations of Physics, Bristol).

6/2023 Invited talk: The problem of pregeometry and selective realism (together with Kian Salimkhani) (CPS, University of Oslo).

3/2023 Invited talk:  General relativity as a classical spin-2 theory? (Oxford Philosophy of Physics Seminar). Click here for the video.

Talk at Oxford (joint work with Chris Smeenk and Mark Baker)

11/2022 Contributed talk: General relativity as a classical spin-2 theory? (Philosophy of Science Association conference 2022 in Pittsburgh)

9/2022 Invited talk: Constructivist approaches to the epistemology of spacetime (Philosophy of Scientific Thought Initiative at the University of Notre Dame).

6/2022 Invited panelist: Discussion on “Beyond the empirical” with Enno Fischer and Kian Salimkhani at the History, Philosophy & Sociology of Cosmology & Astroparticle Physics Conference in Bonn.

6/2022 Contributed talk: A new metaphysics of spacetime at the 1st Bremen-Cologne-Workshop on Time in Cologne.

6/2022 Invited talk: Metaphysics of spacetime, and the role of spacetime functionalism at the Metaphysics Beyond Spacetime conference in Ovronnaz.

4/2022 Invited talk: On the philosophy of chaos theory. In honor of Prof. Dr.-Ing. Erwin Kreuzer’s life work, an expert on chaos theory and former president of the Hamburg Academy of Sciences and Humanities, at the Hamburg Academy of Sciences and Humanities.

4/2022 Invited panelist: Discussion on “Analogue confirmation” with Radin Dardashti and Grace Field at the Bonn HPP Research Seminar in Bonn.

9/2021 Contributed talk: Are there no grand problems of spacetime emergence? (EPSA 2021, symposium contribution, Turin)

9/2020 Contributed talk: Sensible metaphysics without a final physical theory, joint talk with Niels Martens (ERC metascience project workshop, Bristol)

8/2020 Contributed talk: The modal status of the laws of nature. Tahko’s hybrid view and the kinematical/dynamical distinction, joint pre-recorded talk with Salim Hireche, Robert Michels and Lisa Vogt (ECAP10, Utrecht (online))

6/2020 Invited talk: Philosophy of Quantum Gravity as a Philosophy of Generation (Oxford Philosophy of Physics Seminar)

3/2020 Invited talk: Metaphysically Necessary Laws in Physics (ERC-FraMEPhys project, Birmingham)

9/2019 Contributed talk: Quantisation as a method of discovery: the nature and prospects of quantisation approaches to quantum gravity (EPSA 2019, Geneva)

7/2019 Contributed talk: Quantisation as a method of discovery (BSPS 2019, Durham)

4/2019 Invited talk: On Metaphysically Necessary Laws in Physics (DFG Inductive Metaphysics workshop on Counterpossibles, Counternomics and Causal Theories of Properties, Cologne)

2/2019 Contributed talk: On Metaphysically Necessary Laws in Physics (German Society for Philosophy of Science, Cologne)

9/2018 Contributed talk: Does GR need an interpretation? (Swiss Society for Logic and Philosophy of Science: Annual Meeting 2018, Lugano)

3/2018 Contributed talk: Have We Lost Spacetime on the Way? Narrowing the Gap Between General Relativity and Quantum Gravity, joint work with Baptiste Le Bihan (DPG Frühjahrstagung, Berlin)

9/2017 Contributed talk: Quo vadis GR? Indications for an Emergent Nature of GR, together with Manus Visser (Thinking about Space and Time: 100 Years of Applying and Interpreting General Relativity, Bern)

9/2017 Contributed talk: Why the Metric Field and Its Dynamics Should Be Emergent, joint work with Manus Visser (EPSA 2017, Exeter)

8/2017 Contributed talk: On principles of theory construction and justification in quantum gravity, joint work with Karen Crowther (ECAP 9, LMU Munich)

7/2017 Contributed talk: The role of UV completion in the search for quantum gravity, together with Karen Crowther (BSPS 2017, Edinburgh)

2/2017 Contributed talk: How not to establish the non-renormalizability of gravity, poster presentation (Quantum Spacetime and the Renormalization Group conference, Lorentz Center, Leiden)

12/2016 Contributed talk: On principles of theory construction and justification in quantum gravity, together with Karen Crowther (Reasoning in Physics Workshop, Center for Advanced Studies, Munich)

6/2016 Student talk: The Renormalizability of Gravity, joint work with Juliuz Doboszewski (International Summer Institute in Philosophy of Physics, Williamsbay, Wisconsin)

5/2016 Contributed talk: The Renormalizability of Gravity, together with Juliuz Doboszewski (Philosophy of Physics Workshop, University of Bern)

11/2015 Contributed talk: Emergent Gravity vs. Quantum General Relativity? (Philosophy of Physics graduate seminar, University of Oxford)