Am I crazy or is my book wrong?

  • Context: Undergrad 
  • Thread starter Thread starter yjl
  • Start date Start date
  • Tags Tags
    Book Physics
Click For Summary

Discussion Overview

The discussion revolves around a potential discrepancy between a participant's calculations and the equations presented in a professor's LaTeX textbook regarding the Klein-Gordon equation and plane waves. Participants explore the correctness of the equations and the implications of any errors in the text.

Discussion Character

  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions the accuracy of the equations in their textbook, noting a difference in their results, specifically regarding the absence of a term involving c to the power of 4.
  • Another participant confirms that the equation should be ##\omega^2 = c^2 k^2 + c^2 \mu^2## and suggests that if this matches the participant's findings, then their calculations are correct.
  • There is a suggestion that the textbook may have omitted the term μ in one of the equations, which is supported by another participant.
  • Participants express concern about providing feedback to the professor regarding the potential errors in the textbook.

Areas of Agreement / Disagreement

Participants generally agree on the correctness of the equation ##\omega^2 = c^2 k^2 + c^2 \mu^2##, but there is uncertainty regarding the completeness of the textbook's equations. The discussion remains unresolved regarding the overall accuracy of the textbook.

Contextual Notes

The discussion highlights the potential for errors in educational materials, particularly those that are still in development. There is an acknowledgment of the need for feedback on such materials.

Who May Find This Useful

Students and educators involved in physics, particularly those studying wave equations and the Klein-Gordon equation, may find this discussion relevant.

yjl
Messages
8
Reaction score
0
Hey all,

My book says/does the following.

Use the following equation for a plane wave
Aantekening 2019-09-07 020126.jpg

Fill it in the klein-gordon equation
Aantekening 2019-09-07 020112.jpg

To get
Aantekening 2019-09-07 020151.jpg

Which results in
Aantekening 2019-09-07 020201.jpg


Is this right? I got something different and no matter how hard I try I can't replicate the same answer. I've gotten the last equation, but without the c to the power of 4. I also feel like they just flat out forgot μ in the third equation.
 
Physics news on Phys.org
yjl said:
I've gotten the last equation, but without the c to the power of 4.
It should be ##\omega^2 = c^2 k^2 + c^2 \mu^2##, where ##k^2 = k_x^2 + k_y^2 + k_z^2##; if this is what you got then you did it correctly
yjl said:
I also feel like they just flat out forgot μ in the third equation.
Yes.

By the way, what book is this?

Jason
 
jasonRF said:
It should be ##\omega^2 = c^2 k^2 + c^2 \mu^2##, where ##k^2 = k_x^2 + k_y^2 + k_z^2##; if this is what you got then you did it correctly

Yes.

By the way, what book is this?

Jason
Yes, thank you!

That's what I kept ending up on. :-)

It's not a book that's publicly available. It's my professor's LaTeX book that he wrote for the course. He did say that it's still very much a work in progress, but still..
 
yjl said:
It's my professor's LaTeX book that he wrote for the course
I hope you'll tell him about this, politely. If it were me, I would appreciate the feedback. :oldwink:
 
  • Like
Likes   Reactions: vanhees71 and weirdoguy
jtbell said:
I hope you'll tell him about this, politely. If it were me, I would appreciate the feedback. :oldwink:
Yes, I e-mailed him. Wonder if he'll appreciate or find it annoying to be honest
 
yjl said:
Yes, I e-mailed him. Wonder if he'll appreciate or find it annoying to be honest

If he finds it annoying that someone pointed out a mistake in his text, then he has no business being a physicist, or an educator for that matter.

Zz.
 
  • Like
  • Love
Likes   Reactions: vanhees71, jrmichler, berkeman and 3 others

Similar threads

  • · Replies 10 ·
Replies
10
Views
1K
Replies
25
Views
3K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 17 ·
Replies
17
Views
2K
  • · Replies 11 ·
Replies
11
Views
2K