How Is Age Calculated in the Twin Paradox?

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    Paradox Twin paradox
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Discussion Overview

The discussion revolves around the mathematical calculations involved in the Twin Paradox, specifically how to compute the age of the twin who remains on Earth while the other twin travels in a spacecraft for a year. The focus is on the equations used for both unaccelerated and accelerated phases of the journey.

Discussion Character

  • Technical explanation, Mathematical reasoning

Main Points Raised

  • One participant asks for the mathematical approach to calculate the age of the Earth-bound twin when the traveling twin has spent a year in the spacecraft.
  • Another participant provides equations for the unaccelerated and accelerated parts of the trip, specifically mentioning the use of T0 = t1/[squ](1-v²/c²) for unaccelerated motion and T0 = c/a * sinh(at1/c) for accelerated motion.
  • A further contribution questions whether T0 applies to the person on Earth, to which the previous participant confirms that it does.

Areas of Agreement / Disagreement

Participants appear to agree on the mathematical equations relevant to the Twin Paradox, but the discussion does not explore any competing views or unresolved aspects regarding the implications of these calculations.

Contextual Notes

The discussion does not address potential limitations or assumptions inherent in the equations provided, nor does it explore the implications of acceleration on the aging process in detail.

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what is the maths of this paradox?
or more precisely how do you compute the age of the man who stays in Earth while the other one in the spacecraft has spent a year in the vehicle?

thanks in advance.
 
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Originally posted by loop quantum gravity
what is the maths of this paradox?
or more precisely how do you compute the age of the man who stays in Earth while the other one in the spacecraft has spent a year in the vehicle?

thanks in advance.

For the unaccelerated parts of the trip, you use

T0 = t1/[squ](1-v²/c²)

For those parts where the spacecraft is undergoing acceleration, you use

T0 = c/a * sinh(at1/c)

To find v after time t1 at acceleration a:

v = c * tanh(at/c)
 


Originally posted by Janus
For the unaccelerated parts of the trip, you use

T0 = t1/[squ](1-v²/c²)

For those parts where the spacecraft is undergoing acceleration, you use

T0 = c/a * sinh(at1/c)

To find v after time t1 at acceleration a:

v = c * tanh(at/c)
does t0 for the person in earth?
 


Originally posted by loop quantum gravity
does t0 for the person in earth?

Yes.
 

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