Voting over economic plans

We review and provide motivation for a one-sector model of economic growth in which decisions about capital accumulation are made by a political process. If it is possible to commit for at least three periods into the future, then for any feasible consumption plan, there is a perturbation that is majority-preferred to it. Furthermore, plans that minimize the maximum vote that can be obtained against them yield a political business cycle. If it is impossible to commit, voters select the optimal consumption plan for the median voter

Supply chain temple of resilience

In March 2011, an earthquake and tsunami hit the north-eastern coastline of Japan. Honda, Toyota, Nissan and Subaru all had plants in or close to the affected region, and were forced to close them

On an Argument of David Deutsch

We analyse an argument of Deutsch, which purports to show that the deterministic part of classical quantum theory together with deterministic axioms of classical decision theory, together imply that a rational decision maker behaves as if the probabilistic part of quantum theory (Born's law) is true. We uncover two missing assumptions in the argument, and show that the argument also works for an instrumentalist who is prepared to accept that the outcome of a quantum measurement is random in the frequentist sense: Born's law is a consequence of functional and unitary invariance principles belonging to the deterministic part of quantum mechanics. Unfortunately, it turns out that after the necessary corrections we have done no more than give an easier proof of Gleason's theorem under stronger assumptions. However, for some special cases the proof method gives positive results while using different assumptions to Gleason. This leads to the conjecture that the proof could be improved to give the same conclusion as Gleason under unitary invariance together with a much weaker functional invariance condition.Comment: Revision 28-7-03: added reference Final revision 28-05-04. To appear in proceedings of "Quantum Probability and Infinite Dimensional Analysis", Greifswald, 2003; World Scientifi

Marden's Tameness Conjecture: history and applications

Marden's Tameness Conjecture predicts that every hyperbolic 3-manifold with finitely generated fundamental group is homeomorphic to the interior of a compact 3-manifold. It was recently established by Agol and Calegari-Gabai. We will survey the history of work on this conjecture and discuss its many applications.Comment: 30 pages, expository article based on a lecture given at the conference on "Geometry, Topology and Analysis of Locally Symmetric Spaces and Discrete Groups'' held in Beijing in July 2007. Article was published in the proceedings of that conferenc

Global Parton Distributions for the LHC Run II

We review the next generation global PDF sets: NNPDF3.0, MMHT14 and CT14. We describe the global datasets, particularly the new data from LHC Run 1, recent developments in QCD theory and PDF methodology, improvements in combination and delivery, and future prospects for parton determination at Run 2.Comment: 15 pages, 11 figures; talk given at La Thuile, 3rd March 2015; updated reference