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## Main Question or Discussion Point

Prof Ramamurti Shankar has this Youtube video 'Introduction to Relativity' at

And in it he derives the Lorentz Transforms something like this, at about 58 minutes into it.

|------------------------- t ----------------------| time

|-----ut---------------|---------- x' -------------|

|--------------------------- x --------------------|

x' = (x - ut)Ɣ

x = (x'+ ut')Ɣ

Ɣ = 1/(√(1 - (u²/c²)))

x'= (x - ut)/(√(1-u²/c²))

I thought I understood but I now find I don't. Because when I look at that last equation it seems to me that x' is going to increase in length as speed increases.

There's a failure in my understanding somewhere. Can someone please point it out to me?

And in it he derives the Lorentz Transforms something like this, at about 58 minutes into it.

|------------------------- t ----------------------| time

|-----ut---------------|---------- x' -------------|

|--------------------------- x --------------------|

x' = (x - ut)Ɣ

x = (x'+ ut')Ɣ

Ɣ = 1/(√(1 - (u²/c²)))

x'= (x - ut)/(√(1-u²/c²))

I thought I understood but I now find I don't. Because when I look at that last equation it seems to me that x' is going to increase in length as speed increases.

There's a failure in my understanding somewhere. Can someone please point it out to me?