Lorentz Transformations Acceleration: A simple problem

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The discussion revolves around a problem involving two spaceships accelerating near the speed of light, with one ship sending a radio signal to the other. The challenge lies in determining the position and time at which all frames—Earth, ship1, and ship2—agree the signal arrives at ship2. Participants suggest starting calculations in the Earth frame, converting proper accelerations to coordinate accelerations, and setting up equations for both ships' locations over time. They emphasize the importance of understanding how to express the equations of motion for a rocket with constant proper acceleration in the ground frame. The conversation highlights the complexities of applying Lorentz transformations in accelerated frames within special relativity.
Albertgauss
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Hi all,

I came up with the following problem myself and am trying to solve myself. I haven't seen it in any txtbook, grad or undergrad.

Suppose you have the ground frame (Earth).
Earth sees ship1 start at t=0, v=vo1, at x=xo1.
Earth sees ship2 start at t=0, v=vo2, at x=xo2

All velocities are near c. All objects travel along the x-axis only. Let ship2 start ahead of ship1, that is xo2 > xo1.

Earth sees ship2 begin to accelerate at a constant acceleration A at t=0.

If ship1 sends a radio signal (light speed) to ship2, at what position and time will all frames----- Earth, ship1, and ship 2--- say the signal arrives at ship2?

I can easily get x,t v,a for ship 2 as the Earth measures them. That's pretty common, but I can't find any lorentz-transformations for the same set of variables in the frame of ship1 or ship2. I'm willing to do the hard work, but can someone guide me to a resource or some help with how to get X,t for the different frames for such a situation?
 
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Ah yes, The great Albert Guass, one of the greatest mathematicians and physicits of the 1900s :)

I think MTW treats accelerated frames in special relativity. You might find some answers there.
 
Since you are asking for an approach I would first calculate everything in coordinate time, which would be simplest if you take the ground frame.

So you first need to convert the proper accelerations from the rockets into coordinate accelerations which are not constant but decreasing with coordinate time. Then you need to setup the equations for the two spaceships in terms of location and coordinate time. Then pick a point where you want a light signal to leave, with that you can setup the equation for the light path and use this to solve where this light meets the other rocket.

Once you got that you need to convert the coordinate times into proper times.

So the fist thing I would ask you is do you know how to express an equation for a rocket with constant proper acceleration in terms of the ground frame?
 
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MOVING CLOCKS In this section, we show that clocks moving at high speeds run slowly. We construct a clock, called a light clock, using a stick of proper lenght ##L_0##, and two mirrors. The two mirrors face each other, and a pulse of light bounces back and forth betweem them. Each time the light pulse strikes one of the mirrors, say the lower mirror, the clock is said to tick. Between successive ticks the light pulse travels a distance ##2L_0## in the proper reference of frame of the clock...

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