4 ms·

And with 7.8 billion people alive today, if someone does cure aging, we'll have a new problem: who gets to live forever? It can't be everyone, unless no more ch

And with 7.8 billion people alive today, if someone does cure aging, we'll have a new problem: who gets to live forever? It can't be everyone, unless no more children are born.

melling 6y ago
Probably have to leave the planet. the solar system is pretty big. The galaxy is incredibly large, the universe...
- ben_w 6y ago
  That isn’t as helpful as it might seem. If each person has an average of 2.4 offspring, and reproduction still requires two people, and the generation gap is an average of (say) 50 years, and if the average person has a mass of 70 kg; then after 27,000 years the biomass of humanity exceeds the mass of the universe, and after about 18,000 years you need FTL to reach that mass. That said, this remains true even if we don’t solve ageing. Exponentials grow faster than polynomials like “volume”.
  - melling 6y ago
    It’s already at 1.71 in the United States.
inglor_cz 6y ago
There might be a huge gap between finding out "how to live to be 120" and "how to live forever". So far, we can only learn about human aging from people who are at most like 117 years old, because there is no one alive now who would be older than that. So, there is a chance of doing the first steps and finding out that there are other aging-related problems beyond the age of 110-120. Some of them may prove to be unsurmountable. That would probably mean "just" a much longer generation span. People used to have their first kids at 17, in fact they still do in places like Niger or Chad. But in the rich part of the world, length of a generation is now around 30. I can see it being 60 if people live to be 120.
Qwertious 6y ago
If everyone is immortal but only has 1 child per couple, then the population will eventually cap out at double the current population. More generally, as long as the average number of children per couple is less than two, then the population will eventually cap out at a finite number.

And with 7.8 billion people alive today, if someone does cure aging, we'll have a new problem: who gets to live forever? It can't be everyone, unless no more children are born.

melling 6y ago

Probably have to leave the planet. the solar system is pretty big. The galaxy is incredibly large, the universe...

ben_w 6y ago
That isn’t as helpful as it might seem. If each person has an average of 2.4 offspring, and reproduction still requires two people, and the generation gap is an average of (say) 50 years, and if the average person has a mass of 70 kg; then after 27,000 years the biomass of humanity exceeds the mass of the universe, and after about 18,000 years you need FTL to reach that mass. That said, this remains true even if we don’t solve ageing. Exponentials grow faster than polynomials like “volume”.
- melling 6y ago
  It’s already at 1.71 in the United States.

inglor_cz 6y ago

There might be a huge gap between finding out "how to live to be 120" and "how to live forever". So far, we can only learn about human aging from people who are at most like 117 years old, because there is no one alive now who would be older than that. So, there is a chance of doing the first steps and finding out that there are other aging-related problems beyond the age of 110-120. Some of them may prove to be unsurmountable. That would probably mean "just" a much longer generation span. People used to have their first kids at 17, in fact they still do in places like Niger or Chad. But in the rich part of the world, length of a generation is now around 30. I can see it being 60 if people live to be 120.

Qwertious 6y ago

If everyone is immortal but only has 1 child per couple, then the population will eventually cap out at double the current population. More generally, as long as the average number of children per couple is less than two, then the population will eventually cap out at a finite number.