bobng
2009-04-27 19:40:36
So to simplify this we will rely on 3 constants:
The universe is finite - It is expanding therefore it is finite
Time is infinite - Time wont just stop any time soon
The doctor would live forever - He wont just die of old age
So. Assuming the universe is finite, therefore there are a finite number of points in space in it. Just like a box. This space is filled with general crap, like planets, stars and things like that. Now normally this is fine, people live for a finite time and die. No problem there.
But the moment you introduce a time-traveling never-aging doctor then things go a bit wrong. To put this simply, the doctor can travel from the start of the universe to the end, and back again. Therefore given enough time, he will occupy every point in time and space in our universe.
To make it easier to understand, imagine that Dr Who could only time travel when the universe was about to end. So assuming he started at the start of the universe he would occupy space in the universe from the start of the universe to the end. Wherever he is you can find him, he exists. So when the universe ends he travels back to the start again. Now throughout time there are two blue police boxes floating around throughout the univserses time span. Now if you repeat this enough times the universe would be full of police boxes. Because it isn't, he must die.
Simple!
The universe is finite - It is expanding therefore it is finite
Time is infinite - Time wont just stop any time soon
The doctor would live forever - He wont just die of old age
So. Assuming the universe is finite, therefore there are a finite number of points in space in it. Just like a box. This space is filled with general crap, like planets, stars and things like that. Now normally this is fine, people live for a finite time and die. No problem there.
But the moment you introduce a time-traveling never-aging doctor then things go a bit wrong. To put this simply, the doctor can travel from the start of the universe to the end, and back again. Therefore given enough time, he will occupy every point in time and space in our universe.
To make it easier to understand, imagine that Dr Who could only time travel when the universe was about to end. So assuming he started at the start of the universe he would occupy space in the universe from the start of the universe to the end. Wherever he is you can find him, he exists. So when the universe ends he travels back to the start again. Now throughout time there are two blue police boxes floating around throughout the univserses time span. Now if you repeat this enough times the universe would be full of police boxes. Because it isn't, he must die.
Simple!