Feraz Azhar speaks 12/1/21

We are excited to announce that we will have hybrid (in-person and online) talks in December, starting Wednesday, 1st December 2021 at UIC, with Feraz Azhar (Notre Dame) speaking at UIC on Effective field theories as a novel probe of fine-tuning of cosmic inflation.

Abstract: The leading account of several salient observable features of our universe today is provided by the theory of cosmic inflation. But an important and thus far intractable question is whether inflation is generic, or whether it is finely tuned—requiring very precisely specified initial conditions. In this talk I will present work that argues that a recent, model-independent characterization of inflation—-that treats inflation as an effective field theory (EFT)—-promises to address this question in a thoroughly modern and significantly more comprehensive way than in the existing literature. Along the way, I will highlight recent work that addresses the initial conditions problem within the context of a dynamical systems analysis of a specific EFT of inflation, and will describe a roadmap for how such work might be extended to realize the promise claimed above.

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

See the Speakers page for details of timing and location. Hope to see you there!

Predoctoral Fellowship in the Philosophy of Quantum Gravity

The philosophy of physics group at the Department of Philosophy at UIC solicits applications for a junior visiting fellowship for advanced PhD students, starting January 2022 or as soon as possible thereafter, for six months. Candidates must be ABD in a PhD program at an accredited university, working on a dissertation related to the philosophy of quantum gravity or cosmology, broadly construed.

If you are a current PhD student, please consider applying. If you aren’t, please pass this message on!

Full details here: https://beyondspacetime.net/junior-fellowship-in-philosophy-of-quantum-gravity/

Visitor program restarts

We invite interested scholars for short visits to the Cosmology Beyond Spacetime research group located in the philosophy department at the University of Illinois at Chicago in Spring 2022. To facilitate visits we can offer financial assistance for travel and lodging, office facilities, and of course excellent intellectual company. Visits can be from a few days to a few weeks (or possibly longer).

We hope to have range of visitors: faculty and graduate students; general philosophers, philosophers of physics, and physicists; those sharing their expertise, and those learning about the philosophy of quantum gravity and the work of our group and speakers. Visitors will help us inform the philosophical and physics communities about philosophical issues in quantum gravity; and they will help us learn more about these philosophical dimensions though our interactions. While visitors will be credentialed philosophers or physicists, in some cases a credible interest in professional engagement with the group will be more important than prior work in quantum gravity.

In the first instance, potential visitors are requested to send a brief (one page) letter of interest, explaining their current academic status, research focus, and interest in our project. Please also explain any special activities you would like to undertake with the group, date(s) you would like to visit, and estimated cost of a flight. We will request further information as needed, and discuss times and budgets (up to $500, with the possibility of more for longer visits, depending on demand) with successful applicants.

We especially encourage applications from women and underrepresented minorities.

Review of requests will be ongoing.

Send letters of interest to beyondspacetimeseminar@gmail.com. And please share the invitation.

Nick Huggett, UIC

Philosophy Beyond Spacetime published!

Our second collection is published today in the UK (a few more weeks for the US)! Investigations of the philosophical implications of quantum gravity – many thanks to all our authors.

Cover for 

Philosophy Beyond Spacetime
1:Introduction, Christian Wüthrich, Baptiste Le Bihan and Nick Huggett
2:Levels of spacetime emergence in quantum gravity, Daniele Oriti
3:On dualities and equivalences between physical theories, Jeremy Butterfield
4:From quantum entanglement to spatiotemporal distance, Alyssa Ney
5:Taking up superspace: The spacetime setting for supersymmetric field theory, Tushar Menon
6:Thinking about spacetime, David Yates
7:Finding space in a non-spatial world, David J. Chalmers
8:Explanations of and in time, Alastair Wilson
9:Do you see space? How to recover the visible and tangible reality of space (without space), Jenann Ismael
10:The measurement problem for emergent spacetime in loop quantum gravity, Richard Healey
11:The `philosopher’s stone’: Physics, metaphysics, and the value of a final theory, Kerry McKenzie
12:Problems with the cosmological constant problem, Adam Koberinski

Available from OUP here. Get them while they’re hot!

Steven Weinberg (1933-2021)

With sadness we note the passing of Steven Weinberg. His influence on physics has of course been enormous, but – despite his public antipathy to ‘philosophy’ – his conceptual insights into quantum field theory and gravity (and more) have also greatly influenced many of us in philosophy of physics. Notably for me, his work on the renormalization group, the relation between fields and particle in QFT, and – especially relevant to this website – his contributions to our understanding of the scope and limits of gravity as a QFT. Beyond that of course are his amazing popular works in physics, that I expect helped bring many of us to physics in the first place.

April 14th: Callender and Chua speak

Please join us for a talk next week.

Wednesday, 14 April 2021 at 9:30am Chicago Time– Craig Callender (UCSD) and Eugene Chua (UCSD): No Time for Time from No-Time

Programs in quantum gravity often claim that time emerges from fundamentally timeless
physics. In the semiclassical time program time arises only after approximations are
taken. Here we ask what justifies taking these approximations and show that time seems
to sneak in when answering this question. This raises the worry that the approach is
either unjustified or circular in deriving time from no–time.

Join Zoom Meeting: https://uic.zoom.us/j/86317237897?pwd=dSt0N0JsRVVpbEx6Y0EyY1RwKzN4UT09

Meeting ID: 863 1723 7897

Passcode: RMvp1pYM

Huggett speaks this week

March 16 @ 12:00 pm – 1:30 pm Eastern Time (note that US clocks went forward on March 14th, and adjust to your local time accordingly!!!)

Nick Huggett, University of Illinois at Chicago / Center Senior Visiting Fellow

Missing the Point in Non-Commutative Field Theory

This will be an online lecture held via Zoom, and pre-registration is required.  Please register here: https://pitt.zoom.us/webinar/register/WN_8cIVYSN0RfywEh4uJOp0MA

ABSTRACT:  A non-commutative field theory (for scalar fields in this talk) introduces a fundamental area, as the measure of non-commutation (analogous to Planck’s constant), but does it signify a minimum area? Drawing on work with Fedele Lizzi (Napoli) and Tushar Menon (Cambridge) I will explain a sense in which this is correct, implying that points are ‘missing’. This situation raises several questions: how should the theory then be understood? Can its algebraic formulation be interpreted as describing the basic degrees of freedom of a world? And if so, how do we understand the ‘emergence’ of continuous, classical spacetime physics?