Philosophy of Physics Discussion Club

Meetings of the Philosophy of Physics Discussion take place once a month, at the Edelstein Center  (Hebrew University), or at Cohn Insitute (Tel-Aviv University).

2020-2021 meetings of the philosophy of physics discussion club

UPDATE: Due to the Covid-19 situation, spring meetings of 2020 are held via Zoom on  16:00 (13:00 UTC) on June Mondays. Guests and world-wide colleagues are welcome!

Recordings of past talks would be available below for 4 weeks after the talk. 

Past events

June 8th

Continuous Symmetries and Relationalism

Guy Hetzroni, Tel-Aviv University

Recording link: https://openu.zoom.us/rec/share/9epsP7bV7z1OcoXcwmaDX_J-AY_UT6a80SYZqPcEzUmx9R9motECTmbwhQGlQ0oh?startTime=1591621312000

The presented research examines the methods through which symmetry principles are used in three different cases: the gauge principle in QFTs, general covariance in GR, and Mach’s principle in classical mechanics. It is argued that the applications of symmetry arguments these cases are all based upon a hidden assumption stating that transformations between the mathematical representation of a given system have corresponding physical changes in the state of the system with respect to another systems. A natural way to understand this methodology is by appealing to a certain form of relationalism with respect to fundamental degrees of freedom.  I shall try to characterize this relationalism as opposed to other forms of relationalism. Finally, I shall address the distinction between symmetry transformations that have have an active (“Galilean ship”) parallel, and symmetry transformations that don’t, and claim that symmetry arguments that express ontological commitment to relationalism will generally not have a corresponding active symmetry transformation.

June 1st

The Impact of Quantum Mechanics on Philosophy

Lev Vaidman, Tel-Aviv University

Recording: https://openu.zoom.us/rec/share/9elFM-jRsVNJWtLzsRHjY687BZTGaaa8gygdr_ZczEyzpoZgZd-YLipSm2K_ZrLw

Abstract:

Arguably, the main impact of quantum theory on philosophy is that people gave up the hope that science can explain everything in a deterministic way. Some even accepted that science is limited: we cannot explain the objective reality of Nature, only what we can say about it. I will argue that it as an accidental mistake in evolution of science: we have no experimental evidence which requires giving up deterministic description of Nature. Experiments are consistent with determinism if we accept existence of parallel worlds. Multiple worlds might look more problematic than randomness, but not than randomness together with action at a distance. Many-worlds interpretation restore common sense in several paradoxical situations appearing in quantum experiments.

June 22nd; 16:00 IDT (13:00 UTC)

Cassirer on the Methodology of Science: Structuralism, Perspectivism, and Modern Physics

Noah Stemeroff, Tel-Aviv University

Recording: https://openu.zoom.us/rec/share/ovJyAe_5-ENLc4Xi42H1eJMzP6fDeaa8gyEaq6ZenR2j80chfmYj8kKfVct9yrT3

Structural realists suggest, to paraphrase Stein (1989, p. 58), that science comes closest to comprehending ‘the real’, not in its account of ‘substances’ and their kinds, but in its account of its ‘structure’. The structural realist appeals to the convergence of the structural representation of nature through the progress of science to mitigate apparent cases of discontinuity in the history of science (e.g. see Ladyman and Ross, 2007, and French, 2014). Perspectival realists suggest, to paraphrase Rueger (2016, p. 402), that the seemingly incompatible representations of nature given by our scientific theories are, in fact, just representations of the world from different perspectives or points of view. The perspectival realist appeals to a form of inter-perspective translatability and coherence across the progress of science to secure a viable notion of perspectival truth (e.g. see Massimi, 2016). Both structural and perspectival realists seek to defend a selective form of scientific realism in light of the apparent cases of discontinuity and inconsistency in the history of science. They also share an appeal to a form of convergence toward a consistent and unified picture of reality in support of their realist claims. In the context of modern theoretical physics, structural realists and perspectival realists seem to face a common concern—they both need to justify the methodology of mathematical physics and specify a mathematical framework through which the notions of inter-translatability and continuity of structure can be defined.

In this paper, I will present an account of Cassirer’s (1923) critique of the realist justification of the methodology of mathematical phsyics and discuss some of the potential issues this critique might pose for the structural and perspectival realist. Following Cassirer, I will argue that, despite the diversity of physical theories, there is a shared mathematical framework that underwrites the methodology of modern physical enquiry. However, the question remains whether this shared mathematical framework can support the realist claim of continuity or inter-translatability required by the structural and perspectival realist. The convergence of scientific claims secured within the methodology of scientific progress does not, on its own, entail that these claims correspond to the world, as opposed to, say, the constitutive framework of scientific thought. This is the essence of Cassirer’s neo-Kantian critique of scientific realism. Against Cassirer, I will consider whether the mathematical framework underwriting the methodology of physics can be taken to map onto the fundamental structure of reality. To conclude, I will discuss whether this would collapse structuralism and perspectivism into some undesirable form of neo-Pythagoreanism.

June 29th; 16:00 IDT (13:00 UTC)

David Bohm Lectures to a Group of Marxist Physicists, Israel 1957

Hanoch Gutfreund, The Hebrew University of Jerusalem

Recording link: https://openu.zoom.us/rec/share/tOpOaLHex0VIEoXfr3v1aP4vONzcT6a8hyccrvBYzUl3MN8e51kuFGXafYs96O6H

In 1957, when serving as a Professor of Physics at the Technion in Israel, David Bohm delivered a series of lectures on “Philosophical Problems of Quantum Mechanics in the Light of Dialectical Materialism”. The lectures were given to the Group of Marxist Physicists of the Hashomer Hatsair  (Young Guard) Kibbutz Movement. These, recently discovered,  lectures are not known to Bohm scholars and biographers. They shed new light on his rebellion against the quantum orthodoxy. The lecture will present Bohm’s text in the context of his formulation and defense of his causal interpretation of quantum theory in the 1950s. The novelty of this text is that Bohm’s arguments are now, as never before,  presented explicitly and in great detail in the context of dialectical materialism. In the lecture I shall also introduce the intellectual background of dialectical materialism and its influence on Bohm’s thinking through his reading of Hegel, of Marxist literature (Engels and Lenin) and of Greek philosophers (specifically, Heraclitus and Parmenides). Bohm’s lectures will also be discussed in the context of Cold War science with Marxist input on both sides of the debate on the meaning of quantum theory.

14.1.2019 – Cohn Institute (TAU) 15:00 – Eliahu Cohen (Bar Ilan University): In praise of quantum uncertainty

All meeting will be held at the Edelstein Center, Levi building room 324, Safra Campus, Givat Ram, Jerusalem.