Schrödinger's Cat: 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. Projection Postulate Quantum Physics Potentialities Classical Physics Reality

3. Projection Postulate Quantum Physics Potentialities Classical Physics Reality Collapse of wave function by what is commonly called a “measurement”.

5. NO !!!!

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

7. Measurement problem Definition 1: A measurement is something that you do with a measurement device…. Usable in the daily practice of physics, but incorrect: a problem! (von Neumann)

8. Possible solutions • Many World solution (Everett) • Deterministic solution (Bohm) • Objective Reduction (Penrose) • Radical subjective solution (Wigner, Stapp)

9. 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….. Hall, J., Kim, C., McElroy, and Shimony, A. (1977). Wave-packet reduction as a medium of communication. Foundations of Physics7 (1977), 759-767.

10. Experimental Setup Hall, 1977

11. Experimental Setup Hall, 1977 Decay

12. Experimental Setup Hall, 1977 50% of cases pre-observation

13. Experimental Setup Hall, 1977 1 µs delay

14. Experimental Setup Hall, 1977 (final) observation

15. Assumptions • Consciousness of first observer collapses the state before second observation. • Final Observer (brain) is sensitive for the difference between collapsed and non-collapsed state • Final Observer can report this verbally (consciously)

16. Weaknesses in Hall, 1977 • Assumption 1 is violated: Delay between first and second observation too short (e.g. Libet, 1979). • Assumption 3 is inconsistent: The dependent variable is a conscious verbal report, too late! • Libet et al. (1979): Subjective Referral of the Timing for a Conscious Sensory Experience. Brain 102, 193-224.

17. Hall et al. 1977 Delay 1 µs Dependent variable: verbal report Amsterdam 2003 Delay 1000 ms Dependent variable: brain signals Improvements in replication

18. First Amsterdam setup PRE-OBSERVER OBSERVER

19. First Amsterdam setup EEG measurement Deadtime 2000ms Delay 1000ms Geiger Counter OBSERVER 50% Radioactive source PRE-OBSERVER

20. Analysis procedure EEG trace Preobserved beeps NOT preobserved beeps OBSERVER

21. Analysis procedure EEG trace ERP Average EEG from onset-time of event (beep)

22. Results first Amsterdam Setup Bierman, D.J. (2003). Does Consciousness Collapse the Wave-Packet? Mind and Matter 1(1), pp. 45-57

23. Conclusions study 1 • Radical Subjective Reduction supported • A quantum-measurement is only complete when ‘acted’ upon by consciousness. • Copenhagen interpretation supported • The collapse of the wave packet occurs with measurement, creating reality from potentiality. • But wait! • Strong claims need strong evidence, so a second study was performed

24. Alternative explanations • Sensory Cueing (ultra sounds) • EM radiation • Chance

25. Amsterdam 2003 Audio Speakers 16 EEG electrodes Quantum source of measurement Amsterdam 2004 Air-pressure headphones 32 EEG electrodes Quantum & Classical source of measurement Improvements in replication

26. Analysis procedure So now we’ve got 4 different conditions:

27. Hypothesis • Effects of pre-observation in pre-conscious time-interval (0 - ±350 ms) – replication of 2003 experiment • No effects of pre-observation when source is Classic – the state-vector should already be collapsed

28. Second Amsterdam setup EEG measurement Deadtime 2000ms Geiger Counter Delay 1000ms 50% Timed Delay OBSERVER PRE-OBSERVER

29. Second Amsterdam setup EEG measurement Deadtime 2000ms Geiger Counter Delay 1000ms 50% Timed Delay OBSERVER PRE-OBSERVER

30. Results Bierman, D. J., Whitmarsh, S. (2006), Consciousness and Quantum Physics: Empirical Research on the Subjective Reduction of the State Vector. (Book Chapter) The Emerging Physics of Consciousness, The Frontiers Collection. Tuszynski, J. A. (Ed.).

31. Results

32. Results • No effects of pre-observation when source is Classic • No effects found of pre-observation (thus no direct replication of 2003 study)

33. Discussion (no effects of pre-observation) • Uncertainty about the stimulus-origin was introduced by the addition of a classical source: • Conscious observation of the stimuli did not yield a definite measurement because it remained unknown what was actually measured (a quantum or a classic event) • So Subjective Collapse by the pre-observer was actually prevented!

34. Discussion (effect of quantum/singular source) • A different state of event stimuli was still introduced (quantum/classical) • Since the pre-observer could not collapse the quantum state, the effect should still be seen on the final-observer’s EEG… • That’s what we found!

35. Exploration Quantum/Classic

36. Exploration Quantum/Classic

37. Results • No effects of pre-observation when source was Classic • No effects found of pre-observation (thus no direct replication of 2003 study) • Effect of event-origin (quantum/classic) in final-observer’s brain signals!

38. Alternative explanations • Sensory Cueing (ultra sounds) • EM radiation • Chance • Differences in ISI / decay-time distribution • Shorter intervals with quantum vs. classical events post-hoc.

39. Conclusion • Although no direct replication of the 2003 findings, • The second Amsterdam setup is still consistent with the subjective reduction solution of the measurement problem But wait… lets try to reconcile the two… (effect of pre-observer & classic source)

40. ? ! Q C C Q PRE-OBSERVER PRE-OBSERVER Reconciliation in third A’dam setup

41. Sensitivities • Care was taken to maintain exactly the same time-distributions of the quantum and classical events.

42. Preliminary Results • Analysis done over only a fraction of intended number of subjects (20 out of 64).

43. Conclusion • The support for the idea that ‘consciousness collapses the wave function’ has evaporated. • Initial results due to differences in decay-time distribution? • However, it could be that the assumptions underlying this approach are invalid • Consciousness may be not just observing, but measuring We will find out!

44. Thank you for your attention.

45. Shape of difference waves