Understanding Lorentz Transformations: The Role of \bold \tau

[Gyroscope]

It's just a simple question.
In the Lorentz Transformations what means the variable $\bold \tau$?

Thanks, I am deducing this transformations for coordinates, but now I come for this $\bold \tau$ and I cannot deduce if I don't know what it is.

 

[MeJennifer]

It's just a simple question.
In the Lorentz Transformations what means the variable $\bold \tau$?

In principle a variable can stand for anything, but it is conventional in relativity for it to stand for the proper time interval, that is the time interval as measured in the local restframe.

 

[Gyroscope]

Yes, it stands for time.
Is it too difficult for an high school student to derive the Lorentz Transformation for time? For x it was very easy. But I am having problems with time.