/sci/ - Science & Math

For human colonization of space, are space colonies such as O'Neill cylinders and Stanford torus's actually viable options for permanent human presence, or are all space stations too weak and fragile for humans to live on, requiring an entire planet that can take and sustain the abuse that humans make? In other words, if you can't detonate a nuclear bomb on/in it, then it isn't good enough for human living.

Is it economically feasible to construct an L5 colony?
>Guestimate mass required for colony: 10,000,000 metric tons
>@ $100/kg = $1,000,000,000,000 dollars
>Roughly 5% of current GDP for the US
>This is assuming the $100/kg is coming from Earths surface rather than from the moon which would undoubtedly be significantly cheaper per kg (implying we already had infrastructure for large scale mining and processing)