I suppose it depends what your t-axis is doing.

come again?

 

I only know of 3; X, Y and Z axis`

Time dude.

 

The window during which you observe the light will have an effect. You don't want to trace its path forever, so where you decide "that's enough of watching it zoom off in that direction" becomes an important consideration.

 

Or something.

well the way I picture it if you moved the beam from point A to B. and you looked down on the beam it would look like a \ that moves forwards because from the beam ON point at A it would still take time to physicaly move the laser to point B, during that time, the light from point A has traveled further.

wow, I need some more brains or something.

I have always been impressed by the knowledge of people on here such as YT2095 and read their posts with great respect and envy.

So it is a perverse pleasure to see them struggle with the concept of c being the same to all observers regardless of their position or motion relative to the source of said light. Something I finally managed to get my head around and accept some years ago.

No insults intended, it just makes me feel a little less thick when compared to the doubtless superior brains that post here.

May you all continue to amaze and educate me for years to come.