108
society
× 5 |
10
physics
|
5
futurology
× 2 |
3
government
|
52
electricity
× 3 |
10
electromagnetism
|
5
aliens
× 2 |
3
underwater
|
48
politics
× 2 |
10
computers
|
5
travel
× 2 |
3
interspecies-relations
|
44
energy
× 3 |
10
data-storage
|
5
religion
× 2 |
3
crime
|
29
economy
× 4 |
9
population
|
4
moons
× 2 |
2
weapons
× 2 |
28
reality-check
× 7 |
9
earth-like
|
4
trade
|
2
immortality
|
20
warfare
× 4 |
9
planets
|
4
psychology
|
2
space-debris
|
17
space
× 3 |
8
technology
× 3 |
4
teleportation
|
2
natural-disasters
|
16
mars
× 2 |
8
culture
× 3 |
4
alternate-worlds
|
1
military-defense
|
15
science-based
× 3 |
7
law
× 2 |
4
communism
|
1
technological-development
|
15
atmosphere
× 2 |
7
cities
|
4
solar-system
|
1
time-travel
|
11
humans
× 2 |
6
biology
|
3
architecture
|
1
light
|
10
civilization
× 2 |
5
near-future
× 3 |
3
earth
|
1
transportation
|