**Event Categories:** BSPS Choice Group Forum Popper Seminar Sigma Club

## Past Events › Sigma Club

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## Oswaldo Zapata (CPNSS): “Is there still any hope for string theory?”

Abstract: In the first part of the talk we will cover how string theory is related to supersymmetry; and what we can learn from the experiments at the LHC. We will also touch upon how supersymmetry extends our notion of the standard relativistic four-dimensional space-time. A short discussion of supergravity; that is; local supersymmetry; follows. We will see that supergravity…

Find out more »## Joseph Henson (Imperial College London) – “Locality Reinstated?”

Monday 21st October; 17:15pm - 18:45pm SIGMA Speaker: Joseph Henson; Imperial College London Title: Locality Reinstated? Abstract: The assumptions of Bell's theorem were meant by its author to to characterise a lack of any physical superluminal influences. The ``Quantum non-locality'' he discovered does violence not only to our intuitions; but arguably also to any thoroughgoing attempts to apply causal explanation…

Find out more »## Samuel Fletcher (Logic and Philosophy of Science; University of California; Irvine): “On the Reduction of General Relativity to Newton Gravitation”

Monday 4th November; 17:15pm

Find out more »## Richard Pettigrew (Bristol): Accuracy; Risk; and the Principle of Indifference

Richard Pettigrew (Bristol) Accuracy; Risk; and the Principle of Indifference Abstract:

Find out more »## Bryan Roberts (LSE): Three Merry Roads to T-Violation

Title: Three Merry Roads to T-Violation Abstract: This talk aims to give a general perspective on how the fundamental laws of nature can distinguish between the past and the future; or be T-violating. I argue that; in terms of basic analytic arguments; there are really just three approaches currently being explored. I show how each is characterized by a symmetry…

Find out more »## James Ladyman (Bristol): What are Weak Values?

James Ladyman (Bristol) Title: What are Weak Values Abstract: This paper is about the philosophical interpretation and implications of weak values in quantum mechanics. In particular; we present an argument for a subtle kind of retrocausality (which we define as the causal dependence of earlier events on later events) that is based on the probabilistic structure of experiments to determine…

Find out more »## Hans Halvorson (Princeton): Explanation via surplus structure

Our attempts to model physical systems seem to be cursed by the problem of surplus structure: our mathematical representations of such systems contain structure which apparently has no analogue in the system under study. When interpreting our theories; then; we invoke some notion of "physical equivalence" of models in order to wash out this surplus structure. At least that's how…

Find out more »## J. Brian Pitts (Cambridge): Real Change Happens in Hamiltonian General Relativity

Speaker: J. Brian Pitts (Cambridge) Time: 5:15pm - 6:45pm Title: Real Change Happens in Hamiltonian General Relativity Abstract: In General Relativity in Hamiltonian form; change has seemed to be missing; because the Hamiltonian is a sum of first-class constraints and thus supposedly generates gauge transformations. The gauge generator; a specially _tuned sum_ of first-class constraints; facilitates seeing that a solitary…

Find out more »## Owen Maroney (Oxford): How epistemic can a quantum state be?

Speaker: Owen Maroney (Oxford) Time: 5:15pm - 6:45pm Title: How epistemic can a quantum state be? Abstract: The "psi-epistemic" view is that the quantum state does not represent a state of the world; but a state of knowledge about the world. It draws its motivation; in part; from the observation of qualitative similarities between characteristic properties of non-orthogonal quantum wave…

Find out more »## Luke Fenton-Glynn (UCL): Unsharp Best System Chances

Luke Fenton-Glynn (UCL) Title: 'Unsharp Best System Chances' Time: 5:15pm - 6:45pm Abstract: Much recent philosophical attention has been devoted to variants on the Best System Analysis of laws and chance. In particular; philosophers have been interested in the prospects of such Best System Analyses (BSAs) for yielding *high-level* laws and chances. Nevertheless; a foundational worry about BSAs lurks: there…

Find out more »## Katherine Brading (Notre Dame): Absolute; true and mathematical time in Newton’s Principia

Speaker: Katherine Brading (Notre Dame) Time: 5:15pm - 6:45pm Katherine Brading (Notre Dame) Title: Absolute; true and mathematical time in Newton

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