So this is kind of a speculative question but it is something I have long wondered about. I know that if I were to suddenly find myself transported backward in time, say 5000 years, or transported to a primitive earth like planet, chances are that I would probably die in no time at all. I possess no amount of wilderness survival skills, serious science training or much of anything useful at all. Basically I am entirely dependant on the life support system that modern civilization creates. But, what i am wondering is, what about you, or any significantly informed person? Would you or they be able from a beginning of nothing but rocks and wood and all the basic elements of the earth be able to rapidly recreate some semblance of modern technology?. Lets say you had a whole team even. Could you figure out how to obtain and smelt bronze? iron? steel? Could you build that beginning up to where you could create plastics and silicon. Build a radio? a generator? a computer? Plumping? roofing materials? Plaster? nails? tools? explosives? an atomic bomb? Would sufficient knowledge be enough to recreate all this starting from nothing or would you also be hamstrung and lost without the modern world to supply materials and components and tools for you to work with?