Proving Constant Time of "If and, then"

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Homework Help Overview

The discussion revolves around proving that a specific expression related to quantum mechanics is constant in time. The original poster presents a statement involving operators and their time derivatives.

Discussion Character

  • Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Some participants question the completeness of the original poster's attempt, while others explore the implications of setting the time derivative to zero.

Discussion Status

The discussion is in an exploratory phase, with some guidance provided regarding the mathematical expression. However, there is no explicit consensus on the correctness of the approach or the completeness of the solution.

Contextual Notes

There is a lack of clarity regarding the initial conditions and definitions of the operators involved, which may affect the discussion.

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Homework Statement



. Show that if
upload_2015-12-16_16-58-2.png
and
upload_2015-12-16_16-58-2.png
, then
upload_2015-12-16_16-58-2.png
is constant in time.

Homework Equations

The Attempt at a Solution

 
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No attempt?
 
d<A>/dt=i/h x ([H,A]) + dA/dt
Therefore if
upload_2015-12-16_17-12-9-png.93406.png
and dA/dt=0 , then dA/dt=0. Is this it.? :-(
 

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