Upcoming talk: ‘The problem of space in quantum gravity’

I will give a talk on Monday at Boston University’s Center for Philosophy and History of Science, where we will celebrate the 40th Anniversary of the First Osgood Hill Conference on Quantum Gravity. This will be a fun event, with talks by John Stachel, Roger Penrose, George Ellis, Giovanni Amelino-Camelia, and Tian Yu Cao, among others.

Here is the abstract for my talk, entitled ‘The problem of space in quantum gravity’:

Upcoming talk: “Humean possibilities”

On 22 September, at the workshop ‘What is really possible 2 (WIRP-2): Logical and philosophical aspects of real possibility’, at Konstanz–a satellite workshop of GAP8–, I will give a talk entitled ‘Humean possibilities’.

Abstract:

Upcoming talk: “When the actual world is not even possible”

I will be giving a talk at the GAP8 next week in Konstanz, Germany, entitled “When the actual world is not even possible”.

Here is an abstract:

Upcoming talk: “The measurement problem in non-relativistic and relativistic quantum theories”

I will give a talk entitled “The measurement problem in non-relativistic and relativistic quantum theories” at the University of Bern’s Institute for Theoretical Physics on Friday, 14 September 2012.

Abstract:

Upcoming talk: “A prolegomenon to a quantum-information-theoretic complement to a general-relativistic implementation of a beyond-Turing computer”

I will give this talk on 10 September at the “First International Conference on Logic and Relativity: honoring István Németi’s 70th birthday” at the Alfréd Rényi Institute of Mathematics in Budapest.

Here is an abstract:

Upcoming talk: “Putnam looks at quantum mechanics (again and again)”

Next week, on Friday, 22 June 2012, I will give a talk on Putnam’s work on the interpretation of quantum mechanics at the 5th Lauener Symposium on Analytical Philosophy honouring Putnam’s work. The program can be found here. For some reason, I can’t get a direct URL, so you will have to click “Awards/Symposium 2012″, and then “5th Lauener Symposium”.

Here is an abstract of the talk:

Upcoming Talk: “On the Relationship between Spacetime Singularities, Holes, and Extensions”

I will be presenting some recent work at the next Southern California Philosophy of Physics Group meeting (Jan 14, 3:00pm, UC Irvine, SST 777).

Abstract: The Hawking-Penrose-Geroch singularity theorems tell us that (almost) all physically reasonable cosmological models are geodesically incomplete (i.e. they have “singularities”). On the other hand, a number of geodesically incomplete models seem to be artificial in various senses (e.g. they contain “holes” or have “extensions”). Two independent conditions — hole-freeness and inextendibility — serve to rule out some (but by no means all) of these seemingly artificial models. Here, I examine the relationship between these two conditions and the existence of singularities. First, I review what is known: geodesic completeness implies inextendibility. Next, I show that geodesic completeness also implies hole-freeness. (This answers a question posed by Geroch.) In addition, I introduce a simple intermediate condition — effective completeness — which is entailed by geodesic completeness and also entails both hole-freeness and inextendibility. Why might such a condition be of interest? It seems to be strong enough to rule out, in one fell swoop, both types of seemingly artificial models at issue here (and possibly other types as well) but weak enough to allow the more physically reasonable, geodesically incomplete models guaranteed by the singularity theorems. Finally, I show that under certain causality assumptions, there is a useful hierarchy of singularity types: geodesic completeness entails effective completeness which entails inextendibility which entails hole-freeness. 

Upcoming talk: “No categorical support for radical ontic structural realism” (with Vincent Lam)

This Saturday, 8 October 2011, I will give a contributed-paper talk at the EPSA in Athens entitled “No categorical support for radical ontic structural realism”. This is joint work with Vincent Lam; unfortunately, Vincent won’t come to Athens, so I will have to hold the water against the radical ontic structural realist all by myself… Hopefully, there will be some in the audience!

Here is the abstract:

Sigma Club at LSE this term: Harper, Price, Bouatta

Sigma Club at LSE – Michaelmas Term Meetings

Oct 10 William Harper (University of Western Ontario): Isaac Newton’s Scientific Method

Oct 31 Huw Price (University of Cambridge): Retrocausality – what would it take?

Nov 21 Nazim Buatta (University of Cambridge): TBA

Further information can be found at http://www2.lse.ac.uk/CPNSS/events/SigmaClub/Home.aspx

Upcoming talk: “Time Machines: Some Recent Work”

I will be giving the following talk in Turku, Finland on June 9 at the 10th International Conference on Unconventional Computation:

“Time Machines: Some Recent Work”

Abstract: I will consider some recent work on time machines within a particular research program (Krasnikov 2002, 2009; Earman, Smeenk, Wüthrich 2009; Manchak 2009, 2011). The background theory is classical general relativity and the upshot is that there are “time machines” if we assume spacetime is free of “holes”. The talk will make precise what is meant by these words.