11 March: Laura Felline, “The Measurement Problem in Quantum Information Theory”

Our next visitor in the FraMEPhys Seminar series was Dr Laura Felline (Roma Tre) who spoke on Monday 11th March. Laura’s title was ‘The Measurement Problem in Quantum Information Theory’ and her abstract was as follows:

“In this talk I criticize the idea, wide-spread between the advocates of Quantum Information Theory, that in order to explain away the measurement problem it is sufficient to reject the assumption that the quantum state represents physical objects. In order to do that, I will analyse three notable information-theoretic approaches to QT: Bub’s new information-theoretic interpretation (as a representative of a psi-ontic approach), Pitowsky’s Bayesian interpretation (as a representative of an objective psi-epistemic approach) and Qbism (as a representative of a subjective psi-epistemic approach) and argue that the measurement problem still affects the first two interpretations, while Qbism leads to an unacceptable clash between the alleged content of quantum theory and scientific practice.”

Laura argued that the Wigner’s friend thought-experiment, for different reasons in each case, undermines all of the main information-theoretic ‘solutions’ to the measurement problem.

Before the talk, there was a reading group with the speaker in ERI G54 from 1.30-2.30pm. The paper discussed was “An Introduction to QBism with an Application to the Locality of Quantum Mechanics” by Fuchs, Mermin and Schack, available here: https://arxiv.org/pdf/1311.5253.pdf

25 Feb: Antonio Vassallo, “Dependence Relations in General Relativity”

The second talk in our spring FraMEPhys Seminar series was given by Dr Antonio Vassallo (University of Barcelona) on Monday 25th February 2019. Antonio’s title was “Dependence Relations in General Relativity”, and his abstract was as follows:

“I will discuss the nature of the dependence relations underpinning the talk of mutual action between material and spatiotemporal structures in general relativity. In particular, I will present a case study involving frame-dragging effects. Frame-dragging relates local inertial frames to distant distributions of matter in a time-independent way, thus establishing some sort of non-local link between the two. For this reason, a plain causal interpretation of frame-dragging faces huge challenges. By using a generalized structural equation model analysis I will argue that frame-dragging is best understood in terms of a novel type of dependence relation that is half-way between causation and grounding.”

Antonio’s central argument was that the lawlike status of the Einstein Equations renders the overall frame-dragging model explanation as partly causal and partly metaphysical.

There was a reading group before the talk, outside in the February sunshine, where we read Carl Hoefer’s “Mach’s Principle as Action-at-a-distance in General Relativity: The Causality Question”.

Katie Robertson at the Oxford Philosophy of Physics Seminar

FraMEPhys postdoc Dr Katie Robertson gave a talk to the Oxford Philosophy of Physics seminar on Thursday 21 February. Here are the details:

Reducing the second law of thermodynamics: the demons and difficulties
In this talk I consider how to reduce the second law of thermodynamics. I first discuss what I mean by ‘reduction’, and emphasize how functionalism can be helpful in securing reductions. Then I articulate the second law, and discuss what the ramifications of Maxwell’s demon are for the status of the second law. Should we take Maxwell’s means-relative approach? I argue no: the second law is not a relic of our inability to manipulate individual molecules in the manner of the nimble-fingered demon. When articulating the second law, I take care to distinguish it from the minus first law (Brown and Uffink 2001); the latter concerns the spontaneous approach to equilibrium whereas the former concerns the thermodynamic entropy change between equilibrium states, especially in quasi-static processes. Distinguishing these laws alters the reductive project (Luczak 2018): locating what Callender (1999) calls the Holy Grail – a non-decreasing statistical mechanical quantity to call entropy – is neither necessary nor sufficient. Instead, we must find a quantity that plays the right role, viz. to be constant in adiabatic quasi-static processes and increasing in non-quasi-static processes, and I argue that the Gibbs entropy plays this role.

Mathematics, Metaphysics and Evolution (guest post by Aaron Sloman)

Topics discussed on the last day of the FramePhys/Gothenburg conference on Metaphysical Explanation in Science, linking mathematics, science, biological evolution and metaphysics led Aaron Sloman to write some comments available online here:

Inspired by a combination of Immanuel Kant’s philosophy of mathematics and Al Wilson’s notion of grounding as metaphysical causation, Sloman draws attention to the extraordinary metaphysical creativity of biological evolution (the most creative mechanism known to us) repeatedly “discovering” and instantiatiating new metaphysical types of ever increasing complexity and generative power, building on (still unidentified) generative features of fundamental physics that made everything else possible, including increasingly complex and varied forms and uses of information (mostly via chemistry).

He suggests that key features of evolution constitute a process in which pre-existing parametrisable mathematical structures of ever increasing complexity and generative power, are systematically “discovered”, combined and used in creating new (parametrised) instances that when combined with appropriate parameters produce instances of newly discovered metaphysical types, including not only new physical structures and processes but also increasingly complex and powerful new types of information, and information processing mechanisms. This creative, productive, grounding, can be construed as exemplifying Wilson’s characterisation of Grounding as Metaphysical Causation [G=MC].

The details of this process, and its products provide deep challenges for both neuroscience and current AI, neither of which explains the ability of animal brains to discover and use powerful mathematical theories, e.g. concerning topology and geometry. Sloman also links this to Alan Turing’s suggestion (1938) that digital computers cannot replicate human mathematical intuition, only mathematical ingenuity.

— Aaron Sloman

11 Feb: Emily Adlam, “A Tale of Two Anachronisms”

This term sees the start of the FraMEPhys visiting speaker series, and our first speaker was Dr Emily Adlam (BRCP, Leipzig) who spoke on Monday 11th Feb.

Emily’s title was ‘A Tale of Two Anachronisms’, and her abstract was:

“Scientific reasoning is constrained not only by the outcomes of experiments, but also by the history of human thought and our own place in it. As a result, even our best theoretical models often incorporate features which are present more as the result of historical accident than as the endpoint of a process of evidence-based deliberation, and it is sometimes possible to make considerable progress by identifying and eliminating such features. In this talk, I will identify two features of current thought about quantum physics which may be anachronisms of this kind. I will briefly discuss their history and then raise some arguments against them. Both of these features have previously been recognized as problematic by parts of the physics community, but I argue that this recognition is not sufficiently widespread and that both features are actively limiting progress in the field of quantum foundations.”

For those wondering, the anachronisms were: reliance on objective chance, and the avoidance of action that is non-local in time.

The remaining dates in the series are:

25 Feb: Antonio Vassallo (Barcelona)
11 Mar: Laura Felline (Roma Tre)
6 May: Matt Farr (Cambridge)
20 May: Patricia Palacios (Salzburg)
3 June: Mark Pexton (Durham)

— Alastair Wilson

Metaphysics of Entanglement in Urbino

A metaphysician finding inspiration in a metaphysical poet.

On January 22 2019, Al Wilson was in Urbino, Italy to speak at a workshop on the metaphysics of entanglement – the 2021 case study for FraMEPhys. The workshop focused on a new paper by Claudio Calosi and Matteo Morganti, arguing that entangled quantum systems are mutually metaphysically dependent in Kit Fine’s sense of essential dependence. In short, they were arguing that part of what it is to be a particular entangled particle is to be entangled with its partner – and vice versa.

Al’s comments focused on the notion of dependence at work – making use of essential dependence brings some apparently problematic consequences, such as no system being able to survive becoming entangled with (or disentangled from) any other system. He also argued that an underlying monist interpretation of the quantum state continues to offer a more elegant overall explanation of entanglement than the coherentist view. See the slides for more details:

Apparently quantum entanglement is a topic of vital local interest, because a TV crew was present to record proceedings. You can watch a short report on the workshop on RAI TV, starting around minute 16.00.

— Alastair Wilson