Double Slit, Delayed Choice, Quantum Erasure Experiment and Determinism

A couple of days ago, Robin and I took a trip to Piers Gorge, a beautiful stretch of the Menomonee River near Norway, Michigan, in the Upper Peninsula. The river splits Wisconsin and Michigan, and at this point forms a series of Rapids that could almost be called falls. They call these formations “piers”, and they can be accessed by a hiking trail that goes along the river. Robin and I, walked down the quiet paths and marveled at each pier.

It was the third pier we found the most impressive, perhaps because there was a rocky outcrop very close to the water level that jutted out into the river. I ventured out on the rock and sat cross-legged and just watched the water as it tumbled along, making it’s inevitable way through lake and stream to the wide ocean. Out of nowhere that hymn by Isaac Watts that begins, “Time like an ever flowing stream…” started going through my mind.

So I sat there for some moments and prayed for friends and family while that tune went through my mind, but then my mind drifted on to other matters, and as sometimes happens, I started to think about the double slit, delayed choice, quantum eraser experiment. I was associating all that flowing water, the apparent motion of time and the movement of the water with flying photons, wave forms and the implications of all this on theology.

Now, it is important to clarify here that I have pretty much no training in particle physics, and by the same token I am no Augustine, nor Karl Barth, but my mind touches on their domains enough now and then to do a little research and perhaps more dangerously a little contemplation. And here I sat by the river thinking about both physics and theology at the same time. I think it was only the calming effect of the rushing stream that was keeping my head from exploding.

In basic terms, the delayed choice, quantum eraser experiment indicates something remarkable. It shows that something that occurs in the present might be able to affect something that happened in the past. It does this by measuring or not measuring a photon after it has passed through a double slit, causing its wave to collapse or not collapse while an entangled photon at an earlier time is shown to be a wave or particle that coincides with the later event. For a more detailed explanation you can read about it at Wikipedia (https://en.wikipedia.org/wiki/Delayed-choice_quantum_eraser). PBS spacetime has a good video on it as well (https://www.youtube.com/watch?v=8ORLN_KwAgs).

The point for me is not so much that what happens now might affect the past, rather it might be that Calvin was right: that what happens now as well as in the past is predetermined. Calvin’s ideas about determinism (double and otherwise) were based on his understanding of Grace, and its irresistible nature (https://en.wikipedia.org/wiki/Irresistible_grace). But this might extend to all things. God has already determined that the wave form of a photon will be measured, so it will always and forever be collapsed, predestined to be so.

Now, I have heard that this is a hard-hearted idea. If God has already predetermined the outcome of our lives, where does that leave freewill? I think it leaves us in the same place as our photon traveling at light speed through time and space. That photon has innate qualities and those qualities just happen to be cognizant with an outcome that is already predetermined.

But unlike photons, we have consciousness and though the outcome is predetermined we don’t know what that outcome might be, but knowing that we have a gracious God, we must make our evident choices coincide with the will of our gracious God, a God that only wants the best for us.

Amen.

05/05/21 – I recently watched a video about this by Arvin Ash ((1) Entanglement Theory may Reveal a Reality we can’t Handle – YouTube) and found out that John Stewart Bell proposed the idea of Superdeterminism way back in the 1960s. Pretty interesting stuff.