Delayed choice quantum eraser with actual 'choice'?

In summary, there have been experiments where the choice in the delayed choice quantum eraser was more controllable, such as using a beam splitter to make the photons indistinguishable. However, there have also been experiments where the choice was crowdsourced to internet users. The outcomes of these experiments have not been announced yet.
  • #1
greypilgrim
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Hi.

The Wikipedia article on the delayed choice quantum eraser is mostly about Kim's experiment where there's IMHO not really a 'choice' about the erasure of the path information, at least not by the experimentators. Have such experiments also been performed where this choice is more controllable, e.g. by mechanically inserting a beam splitter to make the idler photons indistinguishable (after the signal photon already hit the screen)?

If yes, how was this choice made? I guess all those experiments are faster than a human could press a button. But normal random number generators might present the same possibilities for loopholes as Bell test experiments.
 
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  • #2
greypilgrim said:
Hi.

The Wikipedia article on the delayed choice quantum eraser is mostly about Kim's experiment where there's IMHO not really a 'choice' about the erasure of the path information, at least not by the experimentators. Have such experiments also been performed where this choice is more controllable, e.g. by mechanically inserting a beam splitter to make the idler photons indistinguishable (after the signal photon already hit the screen)?

If yes, how was this choice made? I guess all those experiments are faster than a human could press a button. But normal random number generators might present the same possibilities for loopholes as Bell test experiments.

There actually was a similar experiment just a few weeks ago in which they crowdsourced random choices to internet users all around the world. I don't know if the outcomes have been announced yet though.
 
  • #3
Gan_HOPE326 said:
There actually was a similar experiment just a few weeks ago in which they crowdsourced random choices to internet users all around the world. I don't know if the outcomes have been announced yet though.
Ah, yes! The Big Bell Test -- http://www.thebigbelltest.org/
 
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1. What is the delayed choice quantum eraser experiment?

The delayed choice quantum eraser is a thought experiment that explores the concept of quantum entanglement and the role of observation in determining the outcome of an event in the quantum world. It involves a setup where a particle's behavior is affected by a measurement made on its entangled partner, even if the measurement is made after the first particle has already passed through a series of detectors.

2. How does the delayed choice quantum eraser work?

In the delayed choice quantum eraser experiment, a pair of entangled particles are created and sent in opposite directions towards two detectors. The first particle is split into two paths, one of which goes through a prism that causes the particle to behave like a wave and the other goes through a detector that measures its position. The second particle goes through a similar setup but without the prism. If the second particle is detected, it reveals information about the first particle's path and causes interference patterns to appear, but if the second particle is not detected, the interference patterns disappear.

3. What is the significance of the 'delayed choice' in the experiment?

The delayed choice aspect of the experiment refers to the ability to change the setup of the second particle's path after the first particle has already passed through the detectors. This allows for the observation to be made at a later time, and thus, the experiment challenges the assumption that the act of observation is what collapses the wave function and determines the outcome of a quantum event.

4. What is meant by 'actual choice' in the delayed choice quantum eraser?

The term 'actual choice' refers to the idea that the observer has the power to choose what information is obtained from the second particle's path. In the experiment, this is represented by the choice of whether or not to measure the second particle's path. This concept is significant in understanding the role of consciousness and free will in quantum mechanics.

5. What are the implications of the delayed choice quantum eraser experiment?

The delayed choice quantum eraser experiment challenges our understanding of causality and the role of observation in quantum mechanics. It suggests that the act of observation does not solely determine the outcome of events in the quantum world, and that the future can affect the past. It also raises questions about the nature of reality and the role of consciousness in shaping it.

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