Delayed choice quantum eraser – Yoon Vs Walborn experiment/paper

In summary: You can only manipulate it or set it up in different ways. In summary, the delayed choice quantum eraser experiments conducted by Yoon and Walborn show different ways of manipulating the path of the p-photon. While the Yoon paper does not manipulate the p-photon, the Walborn experiment does. This results in different patterns of interference/non-interference, and raises questions about the nature of quantum randomness and the ability to control it.
  • #1
San K
911
1
Delayed choice quantum eraser – Yoon Vs Walborn experiment/paper

is it true that in the Walborn experiment we manipulate p, but in Yoon paper we do not?

The below link discusses the Walborn paper:
http://grad.physics.sunysb.edu/~amarch/


[PLAIN]http://grad.physics.sunysb.edu/~amarch/PHY5657.gif

s = s-photon, p = p-photon
s-photon is going down and detected by detector Ds
p-photon is going up and detected by detector Dp
The delay (path length) for p is such that s is detected at Ds well before p reaches the polarizer.
Case 1:
The polarizer/eraser is kept there and the experiment is repeated same way for say a million photons (sent one by one)
Case 2:
The polarizer/eraser is removed AFTER s is detected at Ds (and before p reaches the polarizer) and the same sequence of events is repeated same way for say a million photons (sent one by one)

Questions:
a) Will the pattern in case 1 (after correlating the entangled pairs and removing noise) be that of an interference pattern?
b) Will the pattern in case 2 1 (after correlating the entangled pairs and removing noise) be that of a non- interference pattern?


c) In case 2 (or even case 1) when s arrives
a. its position is marked? On the screen of Ds
b. However we do not know which one is the real s till we correlate with p? (i.e. remove noise)
c. Why can we not figure out s simply via timing (velocity, distance, time calculation), without having to correlate with p?

d) Case 2 is interesting because this is different from the experiment by Yoon where we do not mess with p?
Yoon paper is discussed on http://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser

In the Yoon paper the path of p is not “controlled” ….hence when s strikes Ds, one could conclude that the path of p has been fixed (probabilistically) at the time struck Ds.

However the Walborn paper is different -- where we still play with P (after s has struck Ds) by keeping or removing the polarizer/eraser.

Thus

Yoon-kim = DCQE with p allowed to follow whatever path it will take
Walborn = DCQE with manipulation of p?

Yoon = one could still conclude that once s is detected, the path of p is fixed ("probabilistically")
Walborn = we are "operating" on p after s is detected, thus s that has happened in the past is showing results that correlate with p that is (being manipulated) in future?
 
Last edited by a moderator:
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  • #2
San K said:
Delayed choice quantum eraser – Yoon Vs Walborn experiment/paper

is it true that in the Walborn experiment we manipulate p, but in Yoon paper we do not?

The below link discusses the Walborn paper:
http://grad.physics.sunysb.edu/~amarch/


[PLAIN]http://grad.physics.sunysb.edu/~amarch/PHY5657.gif

s = s-photon, p = p-photon
s-photon is going down and detected by detector Ds
p-photon is going up and detected by detector Dp
The delay (path length) for p is such that s is detected at Ds well before p reaches the polarizer.
Case 1:
The polarizer/eraser is kept there and the experiment is repeated same way for say a million photons (sent one by one)
Case 2:
The polarizer/eraser is removed AFTER s is detected at Ds (and before p reaches the polarizer) and the same sequence of events is repeated same way for say a million photons (sent one by one)

Questions:
a) Will the pattern in case 1 (after correlating the entangled pairs and removing noise) be that of an interference pattern?
b) Will the pattern in case 2 1 (after correlating the entangled pairs and removing noise) be that of a non- interference pattern?


c) In case 2 (or even case 1) when s arrives
a. its position is marked? On the screen of Ds
b. However we do not know which one is the real s till we correlate with p? (i.e. remove noise)
c. Why can we not figure out s simply via timing (velocity, distance, time calculation), without having to correlate with p?

d) Case 2 is interesting because this is different from the experiment by Yoon where we do not mess with p?
Yoon paper is discussed on http://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser

In the Yoon paper the path of p is not “controlled” ….hence when s strikes Ds, one could conclude that the path of p has been fixed (probabilistically) at the time struck Ds.

However the Walborn paper is different -- where we still play with P (after s has struck Ds) by keeping or removing the polarizer/eraser.

Thus

Yoon-kim = DCQE with p allowed to follow whatever path it will take
Walborn = DCQE with manipulation of p?

Yoon = one could still conclude that once s is detected, the path of p is fixed ("probabilistically")
Walborn = we are "operating" on p after s is detected, thus s that has happened in the past is showing results that correlate with p that is (being manipulated) in future?

The answer might be that you cannot really control the randomness of the quantum/photon.
 
Last edited by a moderator:

Related to Delayed choice quantum eraser – Yoon Vs Walborn experiment/paper

1. What is the Delayed Choice Quantum Eraser experiment?

The Delayed Choice Quantum Eraser experiment is a thought experiment that illustrates the principles of quantum mechanics, specifically the concept of wave-particle duality. It involves a photon being split into two entangled particles, one of which passes through a double-slit apparatus and the other is measured by a detector. The results of the detector determine whether the path of the photon through the double-slit is known or unknown, demonstrating the role of observation in the behavior of particles.

2. Who conducted the Yoon Vs Walborn experiment?

The Yoon Vs Walborn experiment was conducted by physicists Jaewan Kim, Yoon-Ho Kim, Seung-Woo Lee, and Waldir A. Rodrigues Jr. in 1999 at the Korea Advanced Institute of Science and Technology.

3. What were the results of the Yoon Vs Walborn experiment?

The Yoon Vs Walborn experiment confirmed the predictions of quantum mechanics by showing that the behavior of the photon in the Delayed Choice Quantum Eraser experiment is dependent on the actions of the observer, even after the photon has passed through the double-slit apparatus. This supports the idea that particles can exist in multiple states until observed, and observation plays a role in determining the outcome.

4. How does the Yoon Vs Walborn experiment relate to quantum entanglement?

The Yoon Vs Walborn experiment involves the use of entangled particles, which are two or more particles that are connected in a way that their properties are correlated regardless of the distance between them. In this experiment, the entangled particle that is not observed determines the behavior of its entangled partner, demonstrating the phenomenon of quantum entanglement.

5. What are the implications of the Yoon Vs Walborn experiment?

The Yoon Vs Walborn experiment, and other similar experiments, have significant implications for our understanding of quantum mechanics and the nature of reality. It challenges the classical view of cause and effect, as well as the idea that the observer is separate from the observed. It also has potential applications in quantum technologies, such as quantum computing and cryptography.

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