Somewhat less persuasive talks from the other 3 speakers, including David Wallace who offered a moderate but less than persuasive case for Everett interpretation. I drew his attention to the Midgley Aquarium: it must be a fundamental feature of the world that we have multiple theories and it would be good to develop the sharpest possible arguments for this. Jeremy thinks we could adopt a Gödel-ian approach.
I was able (with permission of the organisers) to invite Denis Noble to join us at the conference dinner: George Ellis was particularly keen to see him again. Denis’s PhD supervisor Otto Hotter is still alive and active which is rather encouraging. I also learned over dinner about the FQXI institute and had an interesting discussion about whether some language-learning capacity is innate with George Ellis.
- After dinner we had a panel discussion moderated by Jeremy Butterfield:
George Ellis gave a masterly canter of a presentation, emphasising that the mental world is real and causally effective: and so is the arrow of time. The universe grows in proper-time-like threads. Causality happens top-down as well as bottom-up and we need to incorporate these facts into our view of tyhe world. Fundamental improvements are needed to Quantum theory as a result.
- Roger Penrose agreed with pretty much all of this. He thinks that the measurement problem may need to be resolved outside our current notions of space-time. He also outlined his views that gravity may cause the collapse of the wavefunction, and hopes that there will be able to be experiments to probe this. Some Japanese researchers (Saito & Fujita),have also apparently made some progress on the properties of biological microtubules.
- John Polkinghorne said he was increasingly encouraged that there might be progress on understanding the collapse of the wavefunction. He doesn’t think it depends on observers but on new physical processes. He very much agrees with Ellis about top-down causality.
Much to my astonishment I was asked to be in a group of four people (led by Andrew Briggs and Jeremy Butterfield) to try to draw together the conclusions into a short set of questions. This was fun and demanding, and I think we have a reasonable set of questions, organised into 5 themes 4 of which have subthemes. It will be really interesting to see how this all develops.