Talk on Wednesday October 19th

• Wednesday 19 October 2016 at Geneva – Marko Vojinovic (University of Belgrade): Quantum gravity, metaphysics, spacetime emergence and locality

Abstract: We will present a brief overview of the various approaches to quantum gravity, with the emphasis on the following questions: (1) why quantize gravity, (2) how to quantize gravity, (3) what is spacetime emergence, and (4) the role of metaphysics in all the above. We will also touch upon the foundational issues of diffeomorphism-symmetric quantum mechanics, and the interplay between locality, the measurement problem, the Schrodinger’s cat paradox and quantum cosmology, leading to some open questions at the foundation of both gravity and quantum mechanics.

In terms of technical difficulty, this talk rates 4/5 4

Prize winning talk on Wednesday

The second of our prize winners will be speaking in Geneva on Wednesday – and via video at UIC and on YouTube. Please join us!

Ko Sanders (University of Leipzig): What can (mathematical) categories tell us about space-time?

Abstract: It is widely believed that in quantum theories of gravity, the classical description of space-time as a manifold is no longer viable as a fundamental concept. Instead, space-time emerges as a suitable approximation. In order to understand what is required to explain this emergence, it is necessary to have a good understanding of the classical structure of space-time.

In this presentation I will focus on the concept of space-time as it appears in locally covariant quantum field theory (LCQFT), an axiomatic framework for describing quantum field theories in the presence of gravitational background fields. A key aspect of LCQFT is the way in which it formulates locality and general covariance, using the language of category theory.

I will argue that the use of category theory gives a precise and explicit statement of how space-time acts as an organizing principle in a systems view of the world. Along the way I will indicate how categories turn physical theories into a kind of models for modal logic, and how the categorical view of space-time shifts the emphasis away from the manifold structure. The latter point suggests that the view of space-time as an organizing principle may persist, even in a quantum theory of gravity, but it may raise new questions.

First talk of the year

We have a number of speakers lined up (with more to come) – the first will be at Geneva next week, and simulcast to UIC .

Wednesday 21 September 2016 at Geneva – Joshua Norton (American University Beirut): Incubating a future metaphysics: quantum gravity

Abstract: In this talk, I will argue that metaphysicians ought to utilize quantum theories of gravity (QG) as incubators for a future metaphysics. In §1, I will argue why this ought to be done. In §2, I will present case studies from the history of science where physical theories have challenged both the dogmatic and speculative metaphysician. In §3, I will present two theories of QG and demonstrate the challenge they pose to certain aspects of our current metaphysics; in particular, how they challenge our understanding of the abstract-concrete distinction. In this section I demonstrate how five different accounts of the distinction each fail to hold under the received interpretations of loop quantum gravity and string theory. The central goal of this talk is to encourage metaphysicians to look to physical theories, especially those involving cosmology such as string theory and loop quantum gravity, when doing metaphysics.

Speakers this Fall at UIC and Geneva announced

We have put together the program with talks at UIC and Geneva this fall semester. More details, including titles and abstracts for the talks, will follow shortly and will be updated, as always, on the speaker page, where you will also find more information:

Looking forward to seeing many of you there. For those who will have to miss the talks, we will make the videos available as soon as they are ready!

Philosophy of Quantum Spacetime for everyone! BST-POP

To celebrate the first anniversary of the Space and Time After Quantum Gravity project, we have published our first Beyond Spacetime Popular (BST-POP) videos, designed for a popular scientific and philosophical audience. So far there are interviews with Richard Dawid and Carlo Rovelli, and a discussion by Keizo Matsubara on the value of philosophy in physics (especially quantum gravity). More are on the way!

The videos are on our YouTube Channel and here – there are video links above as well.

Coming Soon: short lecture series on the philosophy of quantum spacetime, for philosophers. Watch this spot.