Schr ö dinger's Cat: Research on the Radical Subjective Solution of the Measurement Problem.

1. Schrödinger's Cat:Research on the Radical Subjective Solution of the Measurement Problem. . Dick Bierman & Stephen Whitmarsh, University of Amsterdam Presented at QuantumMind, Salzburg, july 15-21, 2007

2. NO !!!!

3. If the measurement is affecting the ‘measured’ it is extremely important to precisely define what constitutes a measurement

4. Measurement Def1: A measurement is something what you do with a measurement device…. Usable in the daily practice of physics But incorrect: a problem! (von Neumann)

5. The Measurement Problem‘solutions’ • Many World solution (Everett) • Deterministic solution (Bohm) • Non linear Schrodinger equation (GRW) • Objective Reduction (Penrose) • Radical subjective solution (Wigner, Stapp)

6. Radical Solution • …. The reduction of the state vector is a physical event which occurs only when there is an interaction between the physical measuring apparatus and the psyche of some observer….. from Hall, J., Kim, C., McElroy, and Shimony, A. (1977). Wave-packet reduction as a medium of communication. Foundations of Physics7 (1977), 759-767. Note that the radical solution is associated with Schrödinger’s Cat.

7. Hall et al experiment

8. Assumptions Consciousness of first observer collapses the state before second observation. 2. Final Observer (brain) is sensitive for difference collapsed and non collapsed state 3. Final Observer can report this

9. Weaknesses in Hall • Assumption 1 is violated: Delay between first and second observation too short • Assumption 3 is inconsistent: The dependent variable is a conscious verbal report, too late!

10. HALL et al 1977 Delay few microseconds Dependent variable: conscious verbal report Amsterdam 2002-2007 Delay 1000 msecs Dependent variable: brain signals before final observer is conscious p Improvements in replications

11. Amsterdam original set-up

12. Amsterdam original set-up Dependent variable: brainwaves of final observer Pseudorandom switch between conditions Pre-observed - not pre-observed

13. Analysis procedure • Predetermined: we only analyze peak amplitudes. • We also apply non-parametric statistics (because of non normality of the distribution of data)

14. Results pooled over condition N200 N160 P100

15. Results split for condition(preobserved and not-preobserved)

16. Study 1-RESULTS peak analysis

17. Control analysis • Split data randomly rather than according to Exp. Condition and repeat analysis. • Effectsizes are on the average an order of magnitude smaller and statistically non significant

18. Conclusions study 1 Bohr • Copenhagen interpretation supported • God plays dice • And …Consciousness stands outside of quantum physics (dualism) or must be considered a ‘hidden variable’ with non local aspects • But wait a minute: Strong claims need strong evidence….. So study 2!

19. Replication set up Alpha source GM detector Count down clock EEG amplifiers Trigger-in delay Audio-beep Final Observer Visual pre-observation for ~ 50% of the events Computer Pre Observer

20. Results averaged over 4 conditions (classical-quantum, preobserved- not preobserved) 4 clusters of electrodes

22. No pre-observation effect But…………

23. An effect of source of events (Quantum vs Classic)

24. Was the (pre) Observation ‘Conscious’ It was less specific than in experiment 1

25. Study 3 More information to pre-observer - I.e. was the source quantum or classic Control of ‘decay-times’ distribution in all conditions.

26. Preliminary Results study 3

27. Review

28. Amsterdam 1

29. Amsterdam 2

30. Amsterdam 3

31. Conclusion • The support for the idea that ‘consciousness collapses the statevector’ has evaporated. • Initial results due to differences in decay time distribution? • However it could be that the assumptions underlying this approach are invalid. • The measurement problem is more alive than ever.

32. Thanks for your attention