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Carl Witthoft
  • Member for 7 years, 8 months
  • Last seen more than a week ago
27 votes

How many people are necessary to maintain modern civilisation?

15 votes

Is it possible for a planet to have the same seasons in both hemispheres?

13 votes

How to supply water to a coastal desert town with no rain and no freshwater aquifers?

12 votes

Biological refrigeration?

12 votes

How Would I Make an Oceanless World Feasible?

11 votes

If you open a 1ft-diameter portal between Earth and space, how fast will the air rush through?

10 votes

Why would a sleeper ship be designed to only wake one person in case of emergency?

8 votes

How much volume does a liquefied human take?

6 votes

The first McDonald's restaurant on Mars

5 votes

Reality Check on Forest Placement

5 votes

How Can An Alien Ship Harness Nuclear Energy?

5 votes

Shooting through the earth

4 votes

Anatomically Correct Creatures that can't be effectively dispatched with guns, but only swords, spears, clubs, quarterstaffs and their like

4 votes

Creating Darkness

3 votes

How would a Grey Goo robot compute given that it has no fixed form?

3 votes

Could somebody get temporarily stuck/“glued” to a wall by way of energy or some other force?

3 votes

In what era or tech level in earth's history did people have the ability to cross a super-earth's ocean 50,000 km wide?

3 votes

Is acid blood possible?

2 votes

Odd-Toed Ungulates

2 votes

How could polycephaly evolve as a byproduct of natural selection?

2 votes

How would normal colors be affected if a planet's atmosphere was green?

2 votes

Underground Base

2 votes

Designing a time thief proof safe

2 votes

Where do producers get nutrients in an airborne ecology?

2 votes

What are the challenges in containing dangerous compounds?

1 vote

Skysteading: How to build a flying city

1 vote

A sound reason for vampires to be weak to sunlight?

1 vote

How does targeting teleportation work without a pad or something?

1 vote

Firearm ammunition surviving 200 years

0 votes

How could a tree survive a volcanic blast?