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BiGyElLoWhAt
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Disclaimer: This isn't a homework assignment, so maybe it shouldn't be in the homework forums. If you feel it should be located elsewhere, feel free to move it, but the template doesn't really apply to this question so...
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So I'm reading Fundamentals of Modern Physics by Eisberg, and I just got through all the Lorentz transforms for space-time coordinates.
In order to do a Lorentz transform on the velocity between reference frames, he differientated (somehow) the spacetime lorentz transforms for the ST coords.
The velocity is presumed to be exclusively in the x direction between both sets of coordinates.
He started with
##x'(x,t) = \frac{1}{\sqrt{1-\beta ^2}}(x-vt)##
and differentiated to get
##dx'(x,t)=\frac{1}{\sqrt{1-\beta ^2}}(dx-vdt)##
I have a couple questions about the legitimacy of this.
1) I think this is called the total differential (?) is this correct? It appears to take the form ##\frac{\partial}{\partial x}x' *dx + \frac{\partial}{\partial t}x' *dt##
2) Assuming this is 100% legitimate (I don't necessarily doubt that it is), when is this method applicable? What are the implications of this method?
I understand that x' is a function of x and t, (it's actually denoted simply x', not x'(x,t) in the book), so the velocity should be dependent on both differentials, but I'm not really seeing the logic behind differentiating this way.
Any help would be greatly appreciated.
Thanks
* * * * * * * *
So I'm reading Fundamentals of Modern Physics by Eisberg, and I just got through all the Lorentz transforms for space-time coordinates.
In order to do a Lorentz transform on the velocity between reference frames, he differientated (somehow) the spacetime lorentz transforms for the ST coords.
The velocity is presumed to be exclusively in the x direction between both sets of coordinates.
He started with
##x'(x,t) = \frac{1}{\sqrt{1-\beta ^2}}(x-vt)##
and differentiated to get
##dx'(x,t)=\frac{1}{\sqrt{1-\beta ^2}}(dx-vdt)##
I have a couple questions about the legitimacy of this.
1) I think this is called the total differential (?) is this correct? It appears to take the form ##\frac{\partial}{\partial x}x' *dx + \frac{\partial}{\partial t}x' *dt##
2) Assuming this is 100% legitimate (I don't necessarily doubt that it is), when is this method applicable? What are the implications of this method?
I understand that x' is a function of x and t, (it's actually denoted simply x', not x'(x,t) in the book), so the velocity should be dependent on both differentials, but I'm not really seeing the logic behind differentiating this way.
Any help would be greatly appreciated.
Thanks