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previous l 13 of 24 I next Why can't we measure the position of a subatomic particle without disturbing it? Drag the terms on the left to the appropriate blanks on the right to complete the sentences. Reset Help longer A subatomic particle is so small that we must use light to measure its position. The interacting photons will impart some momentum to the subatomic particle, thus disturbing it, The shorter the shorter wavelength of the photon, the more accurate the measurement but the longer the momentum greater imparted to the particle and the greater the disturbance. smaller My Answers Give Up Completed Part B How is this concept related to the paradox discussed in the Closer Look box on "Thought Experiments and Schrodinger's Cat Essay answers are limited to about 500 words (3800 characters maximum, including spaces) 3800 Character(s) remainingExplanation / Answer
Schrödinger developed the paradox, to illustrate a point in quantum mechanics about the nature of wave particles.
A cat is placed in a steel box along with a Geiger counter, a vial of poison, a hammer, and a radioactive substance. When the radioactive substance decays, the Geiger detects it and triggers the hammer to release the poison, which subsequently kills the cat. The radioactive decay is a random process, and there is no way to predict when it will happen. Physicists say the atom exists in a state known as a superposition—both decayed and not decayed at the same time.
Until the box is opened, an observer doesn't know whether the cat is alive or dead—because the cat's fate is intrinsically tied to whether or not the atom has decayed and the cat would, as Schrödinger put it, be "living and dead, in equal parts" until it is observed. In other words, until the box was opened, the cat's state is completely unknown and therefore, the cat is considered to be both alive and dead at the same time until it is observed.
In simple words, if you put the cat in the box, and if there's no way of saying what the cat is doing, you have to treat it as if it's doing all of the possible things—being living and dead—at the same time. If you try to make predictions and you assume you know the status of the cat, you're probably going to be wrong. If, on the other hand, you assume it's in a combination of all of the possible states that it can be, you'll be correct.
Immediately upon looking at the cat, an observer would immediately know if the cat was alive or dead and the "superposition" of the cat—the idea that it was in both states—would collapse into either the knowledge that "the cat is alive" or "the cat is dead," but not both.
At the very heart of quantum theory—which is used to describe how subatomic particles like electrons and protons behave—is the idea of a wave function. A wave function describes all of the possible states that such particles can have, including properties like energy, momentum, and position.
The wave function is a combination of all of the possible wave functions that exist. A wave function for a particle says there's some probability that it can be in any allowed position. But you can't necessarily say you know that it's in a particular position without observing it. If you put an electron around the nucleus, it can have any of the allowed states or positions, unless we look at it and know where it is.
That's what Schrödinger was illustrating with the cat paradox, relating to the fact that unless you know that a subatomic particle is moving by disturbing it, it’s position cannot be determined.