Comments for physicspages.com

This blog is for comments and reports of errors on my physicspages.com site. I will also post notifications of new articles published on the main site using this blog, so if you want  to be kept up to date, check here regularly, or else  subscribe to it for email notifications. I realize this may look like a roundabout way of organizing things, but I don’t trust WordPress with anything substantial any more.

If you’re reporting an error or want clarification of an equation in an article, PLEASE include:

  • The URL of the page – just copy this from the browser’s address bar at the top.
  • The equation number containing the error.
  • And of course, what you think is wrong with it.

Thanks, and I hope you find the new site as useful as the old one.

The original post date of each article on the physicspages blog is given at the top of that article.

For articles posted after September 2017, there will be a separate post on the comments blog (this blog), which you can locate in the ‘Archives’ list at the right. You can leave a comment on that particular article from its corresponding entry in the comments blog.

Articles earlier than September 2017 were part of the old site and don’t have
a separate post in the comments blog. If you want to comment on one of these older articles just leave a comment to this header post.

 

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Spacetime volumes

Spacetime volumes

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Twins paradox

Twins paradox

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Spacetime diagrams

Spacetime diagrams

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General boosts and rotations

General boosts and rotations

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Lorentz boosts

Lorentz boosts

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Doppler shift derived without Lorentz transformations

Doppler shift derived without Lorentz transformations

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3-Metric as a projection tensor

3-Metric as a projection tensor

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Frame-Independent Expressions for Energy, Momentum and Velocity

This is a repost of an earlier problem from Misner, Thorne & Wheeler which happens to be the same as the problem in Thorne & Blandford:

Frame-Independent Expressions for Energy, Momentum and Velocity

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Slot-naming index notation and index gymnastics

Slot-naming index notation and index gymnastics

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Numerics of component manipulations

Numerics of component manipulations

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