Lorentz Transformations Acceleration: A simple problem

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SUMMARY

The discussion focuses on calculating the position and time at which a light signal sent from ship1 reaches ship2 in a relativistic context, where both ships are moving at velocities near the speed of light (c) and ship2 accelerates at a constant acceleration A. The Earth frame serves as the reference point for measurements, and the challenge lies in applying Lorentz transformations to derive the coordinates in the frames of ship1 and ship2. Key steps include converting proper accelerations to coordinate accelerations, setting up equations for both ships, and ultimately transforming coordinate times into proper times.

PREREQUISITES
  • Understanding of Lorentz transformations in special relativity
  • Knowledge of proper acceleration and coordinate acceleration
  • Familiarity with the concept of light signals in relativistic physics
  • Ability to set up equations for motion in different inertial frames
NEXT STEPS
  • Study "MTW" (Misner, Thorne, and Wheeler) for insights on accelerated frames in special relativity
  • Learn how to express equations for rockets with constant proper acceleration in the ground frame
  • Research methods for converting coordinate times into proper times in relativistic contexts
  • Explore the implications of light signal propagation in non-inertial frames
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Students and researchers in physics, particularly those focusing on special relativity, accelerated frames, and relativistic motion analysis.

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 Gauss, 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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