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Questions about Measurement/Observations of Quantum Systems

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I've been reading up on some QM lately and one of the things that gets my mind tied in knots is the how the measurement of an electron affects it's path in the double-slit experiment.

 

Isn't our own observation with our own eyes, which uses light in the environment, a form of measurement? If some detector placed within the experiment affects the path of the electron, then how does our own measurements with our own senses, which can be thought of being detectors, affect the path of the electron? We use reflected light as a source of information about the world. Does this light in the environment interact with the electrons in any way? If our own observation with our eyes, that uses light, collapses the wave function, then how does the light in the environment without any observer affect the path of the electron? I hope my question makes sense.

 

Also, when it comes to "spooky action at a distance", physicists tell us that two particles can relay information instantaneously. How do we know that they are actually separate particles, and not one large particle if the measurement of one affects the other? I think that our minds tend to spread out space-time in such a way, and also creates arbitrary boundaries creating separate particles, or objects, that they seem like different things themselves. Does physics, and quantum mechanics specifically, take into account our own brains and sensory systems and how they may interfere, or skew, the results of any observation we make?

Edited by Trajk Logik

note: I am the resident clown, so please wait for a professional to answer your questions.

 

Isn't our own observation with our own eyes, which uses light in the environment, a form of measurement? If some detector placed within the experiment affects the path of the electron, then how does our own measurements with our own senses, which can be thought of being detectors, affect the path of the electron? We use reflected light as a source of information about the world. Does this light in the environment interact with the electrons in any way?

 

You would think so, but whatever glitch is happening seems to require direct atomic scale knowledge. The quantum eraser experiment (as well as this one: https://www.physicsforums.com/threads/double-slit-detectors-question.890825/#post-5604049 ) proves its not the detectors effecting the outcome.

 

If our own observation with our eyes, that uses light, collapses the wave function, then how does the light in the environment without any observer affect the path of the electron?

 

 

I assume that they don't collapse ..they just continue being in a energy wave state until they hit something

 

Also, when it comes to "spooky action at a distance", physicists tell us that two particles can relay information instantaneously. How do we know that they are actually separate particles, and not one large particle if the measurement of one affects the other?

 

 

Entangled particles are thought to be of the same particle ..well, a complex two-particle system with an indeterminate state

 

Does physics, and quantum mechanics specifically, take into account our own brains and sensory systems and how they may interfere, or skew, the results of any observation we make?

 

 

QM is the study of what we are allowed to know

Isn't our own observation with our own eyes, which uses light in the environment, a form of measurement? If some detector placed within the experiment affects the path of the electron, then how does our own measurements with our own senses, which can be thought of being detectors, affect the path of the electron? We use reflected light as a source of information about the world. Does this light in the environment interact with the electrons in any way? If our own observation with our eyes, that uses light, collapses the wave function, then how does the light in the environment without any observer affect the path of the electron? I hope my question makes sense.

 

 

Yes, using our eyes is an act of observation. If we see photons that have interacted with the electron, then that changes the behaviour of the electron. (Actually, the fact a photon interacted with the electron probably counts as an "observation" anyway).

 

 

 

Also, when it comes to "spooky action at a distance", physicists tell us that two particles can relay information instantaneously. How do we know that they are actually separate particles, and not one large particle if the measurement of one affects the other?

 

In fact, it is more accurate to say that the "two particles" are a single system. So there is no need for faster than light communication between them.

 

You would think so, but whatever glitch is happening seems to require direct atomic scale knowledge. The quantum eraser experiment (as well as this one: https://www.physicsforums.com/threads/double-slit-detectors-question.890825/#post-5604049 ) proves its not the detectors effecting the outcome.

 

I would say that this shows that the detectors do affect the outcome. But the effect is non-local in time as well as space.

I would say that this shows that the detectors do affect the outcome. But the effect is non-local in time as well as space.

 

 

You think it does some back-to-future action? I'm in the camp that claims it is the divulgence of information that is effecting it.

The measurement effect is separate from the Heisenberg uncertainty principle. So while bouncing a photon off of an electron has an effect, there is a separate uncertainty about its position and momentum.

 

You think it does some back-to-future action?

 

 

There is a standard interpretation of QM called "retrocausality" which describes it this way. So, yes, if you like.

 

 

 

I'm in the camp that claims it is the divulgence of information that is effecting it.

 

Is it lonely in that camp? :)

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