# Galilean transform and Lorentz transform questions

• rgtr
In summary, the Galilean transform relates the positions of two objects in different rest frames, while the Lorentz transform takes into account the effects of special relativity. Both transformations can be used to switch between the rest frames of two objects, but they are not interchangeable. To practice questions about Galilean transforms, you can try searching for practice problems online or consulting a textbook on classical mechanics.

#### rgtr

Homework Statement
I am just curious about the Galilean transform and the Lorentz Transform
Relevant Equations
## x = x'+vt ##
## x = gamma(x'+vt') ##
I have a quick question about the Galilean transform. If I have Alice running and Bob stationary. The Galilean transform will tell me the position of Alice from Bob's stationary position. Also if I have Alice's position which is moving it will tell me Bob's stationary position.

If I want Bob moving and Alice stationary that is not what the Galilean transform does. Is this correct?

I have not gotten to it yet but previously have read a little bit about the Lorentz transform for position the same logic applies as above.

If I want Bob moving and Alice stationary that is not what the Lorentz transform does. Is this correct?

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rgtr said:
The Galilean transform will tell me the position of Alice from Bob's stationary position. Also if I have Alice's position which is moving it will tell me Bob's stationary position.
No, it will not. It will tell you how the coordinates of an event in Alice and Bob’s rest frames relate to each other.

rgtr said:
Homework Statement:: I am just curious about the Galilean transform and the Lorentz Transform
Relevant Equations:: ## x = x'+vt ##
## x = gamma(x'+vt') ##

If I want Bob moving and Alice stationary that is not what the Lorentz transform does. Is this correct?
No. Both going back and forth between their rest frames are Galilean/Lorentz transformations (which depending on whether you do classical mechanics or special relativity).

Thanks for that clarification. Any idea where I could practice a few questions about Galilean transforms?