Talk:Ringworld

"...the tensile strength of the material required would be on the same order as the nuclear binding force..."

Who wrote this? I'm not so sure of its accuracy. If the rotation of the ring is set to its keplerian velocity, i don't see why you need so big an strength, unless someone calculated that the differential gravity would be so high. Did someone really calculate this? AN

I wrote it. If by "keplerian" velocity you mean orbital velocity, keep in mind that the Ringworld is _not_ in orbit; it is rotating far faster than orbital velocity in order to produce centrifugal pseudogravity. My admittedly somewhat hazy memory tells me that Niven's ringworld rotated at 770 km/s. I'll dig up some specific numbers when I get home if nobody beats me to it. -BD

OK. I had forgotten to consider that. A high tensile strength is indeed necessary.--AN

How about a "Tubeworld" rotating at orbital velocity with transparent "roof" and dark "floor" to keep in the atmosphere and capture the heat (greenhouse effect). Would this get around the tensile strength problem?

I'm sorry, I know this isn't the place to redesign Niven's creation, but I can't resist. It seems to me that my proposed tube structure, if made rigid, would still result in an unstable orbital equilibrium; but, what if we put in a series of flexible "expansion joints" to restore the stability that would be enjoyed by independent segments at orbital velocity?

We could even spin the tube to provide artificial gravity, without undo stress, if we were to spin about the tube’s longitudinal axis rather than about the orbital axis. Admittedly, this might put some stress on the materials and energy loss since the tube has a slight curvature in its longitudinal axis and the materials would have to expand and contract slightly (would this be negligible because of the very large radius of curvature?). --SRWenner

I want to link "nuclear binding force" to the appropriate Wikipedia entry but not sure which it should be.

Anybody?

Having a wild stab and setting it to weak nuclear force :-) --Anders Törlind

I'm not sure whether it's supposed to be the strong nuclear force or the weak one, I'll have to reread an article or two about the Ringworld to dig up better specifics. -BD

Not a Ringworld expert, but I would think that the strong nuclear force would be closer to what is commonly called the "nuclear binding force".

Niven claims he was "forced" to write the sequel Ringworld Engineers, because he didn't realise the Ringworld was not actually in a stable orbit. He says that at a science fiction convetion he attended the halls were full of MIT students shouting, "The Ringworld is unstable! The Ringworld is unstable!" Ah fandom. :-)

If only fandom had used its powers to force him to _not_ write Ringworld Throne... :) (the third book is widely considered to be vastly inferior to the original)

LOL