I'm looking at this question:'If we assume as oscillation of form

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The discussion centers on understanding the concept of operators in the context of quantum mechanics, specifically regarding the oscillation equation y = Aexp(iwt). The term "operator" is clarified as a mathematical function that can transform vectors or functions, with w representing an operator related to energy. The conversation also touches on a homework question about the spread of frequencies in relation to oscillations that decay over time, emphasizing that the definition of "spread" can vary based on the course context. The relationship between angular frequency (ω) and energy (E) is highlighted, with the operator for frequency derived from these principles. Overall, the thread seeks to clarify foundational concepts in quantum mechanics for better understanding.
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I'm looking at this question:

'If we assume as oscillation of form y = Aexp(iwt) what is the operator w? What then is the operator for frequency f?'

I have no idea what is ment by operator. I've tried looking it up in books and the net, but the explinations I am finding just aint helping me. Can anyone tell me how to find an answer to this question. (this isn't a homework question btw)


Another question (this is a homework question):

'An oscillation of frequency f dies out after approximately 10 seconds. What is the approximate spread of the frequencies.'

My question is, what is ment by spread?
 
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What course are you taking and what are the problems around this one like?

I ask that because there can be a number of different answers to your question depending on the course.

In "basic" algebra, something like "y = Aexp(iwt)" would be a function of a real number and w would be a number. In linear algebra, t might be a vector in which case w would be a function taking one vector into another: an "operator". In quantum physics (not mathatics at all) what are numerical properties of of particles (position, velocity, momentum, energy, etc.) become operators on the quantum space. Certainly if you are expected to do a problem like this, you should already have been introduced to the notion of an "operator".
 
hmm

Its for a quantum mechanics course. The course started last week, and we've not covered much yet. I'm doing my own reserch into it. That problem was found on last years exam paper. Was just curious as to what an answer would be, and how u arrive at that answer.
 
The operator for ω is related to the operator for the energy E, since E=(hbar)ω (still haven't got this Latex thing down yet).

So, ω=(1/hbar)E=(1/hbar)(i*hbar)(∂/∂t)

or ω=i(∂/∂t). The operator for the frequency follows similarly from the relation between E and f, or from ω and f, whichever you like best.
 
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