How do you observe the position of an electron?

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    Electron Position
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Discussion Overview

The discussion revolves around the methods of observing the position of an electron, particularly through the use of x-rays and the implications of such observations on understanding electron behavior. It touches on theoretical and experimental aspects of electron detection and measurement, as well as the limitations imposed by quantum mechanics.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions the use of x-rays for observing electron position and inquires about the effects of x-rays on electrons in atomic orbitals.
  • Another participant suggests that focusing x-rays on a small area can help determine the origin of a kicked-out electron, but acknowledges the challenge of measuring its velocity.
  • A participant raises a question about the resolution capabilities of current x-ray technology in relation to atomic dimensions.
  • There is a discussion about the distinction between speed and velocity of electrons, with a participant comparing it to billiard balls and questioning the relevance of velocity at impact.
  • One participant claims that if terminal velocity and detector position are known, it could allow for solving the velocity at collision and inferring position, challenging the uncertainty principle.
  • Another participant counters that measurements come with degrees of error and emphasizes that certainty in predictions is not achievable.

Areas of Agreement / Disagreement

Participants express differing views on the implications of measuring electron position and velocity, particularly in relation to the uncertainty principle. There is no consensus on the validity of the claims made regarding measurement techniques and their implications.

Contextual Notes

The discussion highlights limitations related to measurement accuracy, the dependence on definitions of velocity and position, and the unresolved nature of quantum mechanical principles in this context.

Helicobacter
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How do you "observe" the position of an electron?

Do you use x-rays?

If so, what happens when you hit the orbital of a given atom with x-rays? Will it just accelerate the electron(s) out of the orbital? Also, how can you then infer the position the electron had initially occupied? Do you just have detectors set around the bombarded atom? Since you know everything about your fired x-ray (intensity, wavelength etc.), you can solve for the position at impact? EDIT: You probably can't, because which detector is hit by the electron depends on the velocity and position of the electron at impact (neither of which you know). EDIT2: But if you know the temperature of the atom, then do you not know at what velocity the kicked-out electron moves? EDIT3: You only know speed but not the actually direction of motion?

Then, when this experiment was repeated a lot of times, the probability density functions were established?
 
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X-ray is just one of the solutions.
You may focus your X-ray on a very small area. So if you notice the electron kicked out - you are sure it got kicked from the focus point.

You may also build pretty small detector to catch electrons. Actually, such detector may be not much bigger than single molecule.

If you don't need such accuracy - watch TV (old-fashioned, CRT, not a flat one) As the electron hits the screen it flashes.
 


xts said:
X-ray is just one of the solutions.
You may focus your X-ray on a very small area.

With current technology, at what resolution can we focus an xray beam (in units of a hydrogen atom diameter, say)?

xts said:
So if you notice the electron kicked out - you are sure it got kicked from the focus point.

But you don't know what the velocity of the electron was. You might know speed but not velocity. Is it not like Billiard balls? Does the velocity of the electron not matter (e.g., if the xray photon [the cue] hit the electron [8-ball], does the velocity of the 8-ball not matter at impact?
EDIT: Nevermind, you're right. You do not measure the final electron velocity or even which detector was hit - just the fact that is was kicked out, and the knowledge of which region within the orbital you beamed away.

EDIT2: What if you did measure terminal velocity (at detection) and terminal detector position? We know xray photon velocity, speed of electron at impact (from room temperature), velocity of electron at detection, detector position that's being hit by the electron - we can solve for velocity at collision. Also, from your inference we can determine position simultaneously. Therefore, I claim that the uncertainty principle is bogus. Where is my mistake?
 
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you know it only with a degree of error, the smaller that error for velocity the greater the error for its exact position. Also you seem to be inferring that we can predict one thing from the result another, but we cant, not with certainty.
 

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