# 265: Choices: Part 2

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 Choices: Part 2 Title text: Maybe someday I'll get to write the Wikipedia article about this place! Wait, damn, original research.

## Explanation

This is a little sidetrack from the "Choices" narrative. Cueball is studying special relativity. The speed of light in vacuum (299,792,458 m/s) is denoted c. Megan and the spaceship are shown traveling at 0.2c in opposite directions. This would mean (in Newtonian mechanics) 0.4c relatively to them. But due to relativistic effects, their velocities do not simply add when the spaceship observes Megan, in reality both would measure only 0.385c ( = (u + v)/(1 + uv/c2). ) from the other's point of view. Also, time dilation influences the way time is observed WRT the two frames of reference. Megan, however, has other concerns.

In the title text Megan thinks about writing about this after-worldly place in Wikipedia, but then realizes that the content would be removed, due to the Wikipedia policy on original research. Even though her claims would be true, she would need reliable written sources to support them.

All parts of "Choices":

## Transcript

[Cueball is doing some exercises in a book. The clock on the wall says 12:50.]
Chapter 15: Special Relativity
Problem 1:
Two spacecraft transmit messages to each other while passing at constant velocities of...
Cueball: sigh
Meanwhile:
[Megan in a bubble and a spacecraft are moving towards each other. Each one has a velocity vector drawn before themselves, each showing a velocity of 0.2c.]
[They pass each other.]
Spacecraft: We observe your speed to be 38.5%c, and your time is passing at 92.3% the rate of ours. Does this mirror your observations?
Megan: Please help me. I think I'm lost.
[They continue with the same velocity vectors. Megan is looking back at the spacecraft.]

# Discussion

Created the "Choices: Part 3" page (its a bit of a fail), Please link it to here. 121.54.48.38 02:11, 14 May 2013 (UTC)

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