Arcadian Functor

occasional meanderings in physics' brave new world

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Marni D. Sheppeard

Thursday, November 26, 2009

FFP10 Day 2

On Day 2 of FFP10, John Hartnett spoke about an alternative cosmology that does not require gravitational waves.

In a later, split session on alternative cosmologies, we heard from Robin Booth, who has a concrete prediction for the recently launched Planck: the photon noise for the CMB should be 40 times that predicted by the standard cosmology. Perhaps more on the quasars later.

So by the time it came to the conference dinner, in the extravagant University Club, all participants seemed quite comfortable telling jokes about how many string theorists it takes to change a light bulb.

Wednesday, November 25, 2009

FFP10 Day 1

FFP10 has a variety of interesting badge wearing participants, including Apoxyomenos. However, as a statue, Apoxyomenos has difficulty taking a seat in the air conditioned lecture hall.

Professor 't Hooft began the proceedings with his lecture on Gravity and the Quantum. First he discussed a concept of classical black hole complementarity for internal and external observers: the former seeing objects behind the horizon, but no Hawking radiation, and the latter observing Hawking radiation. In principle, these observers should see the same physics. The proposal of so called extreme complementarity sets up a perfect time reversal symmetry between the causal structures for internal and external observers. These assumptions allow for a conformal factor relating two observations, and the suggestion that generators of scale transformations have a non local character. The second part of his talk discussed cellular automata as deterministic systems with a quantum mechanical description. That is, acceptable hidden variables in a theory of dynamics of states.

Huw Price thankfully managed to avoid multiverses in the first half of his talk on Time's Arrow and Eddington's Challenge, starting with a clear explanation of the distinction between dynamic and block views of Time (although the potential use of both together was not, as usual, considered). The most notable proponents of the latter view, in relatively modern times, include Einstein and Boltzmann. On the dynamical side we have Eddington, who, in 1928, said:
Events give ... no indication that they undergo what has been described as the formality of taking place.
Eddington supposedly coined the concept of the changing world as becoming, but that sounds rather like Hegel to me. Unfortunately, from this point on, the multiverse takes over as an attempt to address the challenge of Time's Arrow ... by creating universes that restore the overall symmetry.

Friday, November 27, 2009

FFP10 Day 3

The three days of the conference passed quickly, and it seems that most people have already left Perth. I arrived early on the last day, in order to spend time with the lorakeets, kookaburras, ducklings and galahs.

Links: The Halton Arp website has interesting quasar information, as discussed by C. Fulton. The conference proceedings will be published early next year, and you can now play spot the physicist on the conference photo.

Monday, November 23, 2009

From Perth

Carl and I are now happily settled at UWA, enjoying Perth's notoriously perfect weather. We are only a 5 minute walk from beaches on the Swan river. The FFP10 fun starts tomorrow.