It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Some features of ATS will be disabled while you continue to use an ad-blocker.
1) the experiment is executed.
2) the experiment finishes.
3) the non-interference pattern appears on the screen.
4) the which-path info is erased.
5) the interference pattern appears on the screen.
The flow of events is: 1) the experiment is executed. 2) the experiment finishes. 3) the non-interference pattern appears on the screen. 4) the which-path info is erased. 5) the interference pattern appears on the screen. In other words, an event that happens after another event affects that event.
No, it's not a logical fallacy. Things happen when we don't look.
But the particles have already hit the screen before the erasure happens, so the non wave pattern is already on the screen. It is there, it's set, it shouldn't be changeable, yet when the wich path info is erased, it does show the intereference pattarn when they look at the screen for the first time.
The experiment has two stages: first the experimenter marks through which slit each photon went, without disturbing their movement, and demonstrates that the interference pattern is destroyed. This stage shows that it is the existence of the "which-path" information which causes the destruction of the interference pattern. The second stage goes by erasing the "which-path" information, and demonstrating that the interference pattern is recovered. It does not matter whether the erasure procedure is done before or after the detection of the photons.
Quantum eraser experiment
Originally posted by masterp
reply to post by RandomEsotericScreenname
You are correct that the availability of the 'which path' determines the particle status as a wave, but you are wrong that this has to do with human consciousness. The particle regains its wave status simply because the information is erased, not because a human observes it.
reply to post by followingpythagoras
reply to post by djmarcone
They erase the which path data, the interference pattern returns because the information is gone. Does the pattern return because a human CAN NOT view the data or DOES NOT view the data? In other words, if the experiment runs unattended does the pattern show up? Or is that a moot point because if it is unattended there is no-one to see the pattern either....
The pattern does not magically change. It is only observed at the end of each experiment.
Originally posted by masterp
Originally posted by RandomEsotericScreenname
reply to post by masterp
You haven't got a clue have you. The wich path info is erased AFTER the particles have already hit the screen when the wich path info was still available.
Then the info is erased, but the pattern associated with the info being known should be on the screen, because it is erased afterward.
Yet when the experimenter looks, it shows an interference pattern. This is impossible.
It is not impossible at all. In the quantum world, causality can be violated. The theory of relativity has not yet been linked to quantum physics.
The presence of an experimenter is irrelevant. It is the properties of the quantum world that do this.
A new experiment may prove that it is possible to send information back in time:
In this experiment, the outcome of an event is present before its cause.
Consciousness has nothing to do with it (because consciousness actually does not exist, it is simply the thought processes of the brain).
Please respond to my claims about the Quantum Eraser Experiment, wich is what this thread really is about like I clearly said.
reply to post by phishyblankwaters
In physics, the term observer effect refers to changes that the act of observation will make on the phenomenon being observed. This is often the result of instruments that, by necessity, alter the state of what they measure in some manner.
The delayed choice quantum eraser, allows the decision whether to measure or destroy the "which path" information to be delayed until after the entangled particle partner (the one going through the slits) has either interfered with itself or not. Doing so appears to have the bizarre effect of causing the outcome of an event after the event has already occurred. In other words, something that happens at time t apparently reaches back to some time t - 1 and acts as a determining causal factor at that earlier time. However, the interference pattern can only be seen retroactively once the idler photons have already been detected and the experimenter has obtained information about them, with the interference pattern being seen when the experimenter looks at particular subsets of signal photons that were matched with idlers that went to particular detectors.
The delayed choice quantum eraser, allows the decision whether to measure or destroy the "which path" information to be delayed until after the entangled particle partner (the one going through the slits) has either interfered with itself or not. Doing so appears to have the bizarre effect of causing the outcome of an event after the event has already occurred. In other words, something that happens at time t apparently reaches back to some time t - 1 and acts as a determining causal factor at that earlier time.
By proving that the detectors which don't give path information have an interference pattern, and the detectors which do provide that information don't, they were able to prove that the resulting pattern is determined by the ability to determine the path information.
The detectors that show the the wich path info don't show an interference pattern, the detector screen does.
The signal particles go directly to the screen, the idlers, or entangled partners go to the detectors that show either "wich path" info available, or not.
I think that what this shows is complex. It does not show that "human consciousness" controls all things, because it relies on the physical act of measurement