Hello, and Welcome to Zombie Physics 101
Jan. 23rd, 2007 09:33 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
raegan_1For lo, I am a geek obsessed with zombies, even while playing with special relativity. The question is behind the cut.
In 2234, we discover that a satellite between us and the sun is carrying the zombie virus. It is going to explode soon and the virus will be sent toward Earth. At the same time, we learn a satellite carrying the anti-virus is at resting in space in the exact opposite direction, but is also set to explode. We get in a spaceship and head toward the satellite with the antivirus. When we reach the midpoint between the satellites, we see both explode simultaneously. (a) Will the virus and the anti-virus, both traveling at 0.10c, reach us at the same time? (b) The antivirus, once taken, will immunize us against the virus. However, it is not a cure and once infected by the virus, the anti-virus does nothing. What is the fate of those left on Earth? What is the fate of those on the ship if the Earth is the only inhabitable planet within range?
In 2234, we discover that a satellite between us and the sun is carrying the zombie virus. It is going to explode soon and the virus will be sent toward Earth. At the same time, we learn a satellite carrying the anti-virus is at resting in space in the exact opposite direction, but is also set to explode. We get in a spaceship and head toward the satellite with the antivirus. When we reach the midpoint between the satellites, we see both explode simultaneously. (a) Will the virus and the anti-virus, both traveling at 0.10c, reach us at the same time? (b) The antivirus, once taken, will immunize us against the virus. However, it is not a cure and once infected by the virus, the anti-virus does nothing. What is the fate of those left on Earth? What is the fate of those on the ship if the Earth is the only inhabitable planet within range?
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no subject
on 2007-01-25 11:39 pm (UTC)no subject
on 2007-01-26 04:04 am (UTC)And as for an answer: would you like the answer, or was that more of a "Wish I had the time to actually sit down and figure this out myself" kind of wanting an answer?
no subject
on 2007-01-26 12:53 pm (UTC)no subject
on 2007-01-29 01:53 am (UTC)A-------R---E----V------S
The Rocketship is travelling toward the antivirus when both satellites go boom. We see the light of the explosions at the same time, because at that point in time, we are halfway between both satellites. Earth is not so lucky, but we'll get to that in a moment.
When the satellites blow, they send out the virus and the antivirus at the same speed, 0.10c, which is 1/10 the speed of light (meaning the light reaches us ten times as quickly as the virus/anti-virus would, if we were at rest.) Because we're traveling in the direction of the anti-virus, as we continue flying after the explosion, we are getting closer to the anti-virus and farther from the virus, and the anti-virus will reach us first. That means that all of those on the ship are not and will never be zombies. Yay, us!
But back on Earth, which was closer to the satellite with the virus, the virus hits quite a while before the anti-virus, and the population of the world is flooded quickly by zombies. This is bad, for them, yes, but also bad for us, because our rocketship has no place to go now but back to the zombie-infested Earth. The answer to (b) is that we are all doomed. Woobie.
The answer to (a) is that, no, the virus and the anti-virus won't reach the rocketship or the earth at the same time, because they travel at the same speed across different distances.
The figure above will look something like this when the anti-virus/virus reach us/Earth.
A----R------E----V------S