What is the Commutator of [x, p e^(-p)]?

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SUMMARY

The commutator of the position operator \( x \) and the momentum operator \( p e^{-p} \) is calculated to be \( i - i e^{-p} \). In quantum mechanics, \( x \) represents position and \( p \) represents momentum, adhering to the standard commutation relation. The solution involves recognizing the multiplicative factor in the exponential and applying the shortcut formula for commutators of the form \([x, f(p)]\). Expanding \( e^{-p} \) into a power series is also a valid method for solving this commutator.

PREREQUISITES
  • Understanding of quantum mechanics, specifically the operators \( x \) and \( p \).
  • Familiarity with commutation relations in quantum mechanics.
  • Knowledge of power series expansions.
  • Experience with mathematical notation and manipulation in physics.
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  • Study the derivation of the commutation relation \([x, p]\) in quantum mechanics.
  • Learn about the shortcut formulas for calculating commutators, specifically \([x, f(p)]\) and \([p, g(x)]\).
  • Explore the properties of exponential functions in quantum mechanics, particularly \( e^{-p} \).
  • Review power series expansions and their applications in quantum physics.
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Students of quantum mechanics, physicists working with operator algebra, and anyone interested in advanced mathematical techniques in quantum theory.

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Poster has been warned that he needs to show effort before he can be given help

Homework Statement


commutator of [x,p e^(-p) ]

Homework Equations

The Attempt at a Solution


answer is i - i.e^(-p)
 
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what is p in the e^(-p)?
 
If it's the usual notation for quantum mechanics, x is position and p is momentum.
 
its just the usual commutation relation of x and p with e^(-p) in multiplication.
the method of solving remains the same.
 
I will assume that the multiplicative factor which should exist next to the momentum in the exponential in order to conform with the dimensionality is presumed to be unity. There is a shortcut formula for calculating commutators of the form [x,f(p)] and [p,g(x)]. In case you never heard about it, you should then do the calculation by first expanding ##e^{-p}## into power series and use the fundamental commutation relation between x and p.
 
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Prins said:

Homework Statement


commutator of [x,p e^(-p) ]

Homework Equations

The Attempt at a Solution


answer is i - i.e^(-p)

You absolutely need to show your efforts before you can get tutorial help here on the PF. That is clear in the PF rules (see Info at the top of the page). This thread is locked. If you want to re-post your question and fill out the Homework Help Template completely, you may do that.
 

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