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!
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!
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.
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.
Blog followers may be interested in the following interview of Tushar Menon by David Baker, on “Taking up Superspace”, a paper published in the project collection “Philosophy Beyond Spacetime” (OUP, 2021). https://www.youtube.com/watch?v=4Mj_3FZWMIM
We are delighted to announce that Mike Schneider (currently a postdoc at Pittsburgh) will be joining our group at UIC as a postdoctoral research fellow for 2021-22. If you don’t yet know Mike, you can read about his work on his website.
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.
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?