Bruce Gordon: So what does the “delayed choice“ quantum eraser experiment do? Well, it tries to measure which path a particle would have taken after interference in the wave function has been created that is inconsistent with that particle’s behavior. So you’ve got a splitter of some sort. It’s going to divide the quantum wave function and send it along two different paths. Then you’re going to make a measurement along one of the paths to see what’s happening.
That interference can be turned off or on by choosing whether or not to look at which path the particle has taken after the interference already exists.
Now if you don’t look, you get an interference phenomenon at the end. If you do look, the wave function instantaneously collapses and you detect the particle along that pathway. So choosing to look erases the wave function and gives the system a particle history.
This experiment has been performed under what would be called Einstein Locality Conditions. In other words, no signal could have passed — subject to the limiting velocity of the speed of light — between the components of the system to cause the effect that you’re observing.
The very fact that we can make a causally disconnected choice of whether wave or particle phenomena are manifested in a quantum system essentially shows that there is no measurement-independent and causally connected, substantial material reality at the micro physical level. It is created by the measurement itself.News, “In quantum physics, “reality” really is what we choose to observe” at Mind Matters News
Takehome: Gordon explains that the quantum eraser experiment shows that there is no reality independent of measurement at the microphysical level. It is created by the measurement itself.
Here are stories from Bruce Gordon’s previous podcast with host Michael Egnor, where he defends idealism as a way of making sense of nature:
Why idealism is actually a practical philosophy. Not what you heard? Philosopher of science — and pianist — Bruce Gordon says, think again. Is reality fundamentally more like a mind than a physical object? Many are sure of the answer without understanding the question.
A physicist and philosopher examines panpsychism. Idealism says everything is an idea in the mind of God. Panpsychism says everything participates in consciousness (thus is not just an idea). Bruce Gordon thinks that, for a thing to be conscious, there must be something that it “is like” to be that thing. Can panpsychism demonstrate that?