I Am I crazy or is my book wrong?

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The discussion centers on a potential error in a professor's LaTeX book regarding the Klein-Gordon equation for a plane wave. Participants confirm that the correct equation should be ω² = c²k² + c²μ², where k² = k_x² + k_y² + k_z². One user expresses concern about missing terms in the equations presented in the book. The conversation also touches on the importance of providing constructive feedback to educators about their materials. Overall, the participants agree on the necessity of accuracy in educational resources.
yjl
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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.
 
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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:
 
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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.
 
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