Can a Balloon Float Inside a Hollow, Air-Filled Space Elevator?

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udtsith
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What would the problems be with having a hollow cylindrical space elevator made of carbon (e.g. recent benzene linked chains) and instead of having the payload climb to the top you filled the inside with 1 ATM of air and floated to the top via balloon?
 

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udtsith said:
What would the problems be with having a hollow cylindrical space elevator made of carbon (e.g. recent benzene linked chains) and instead of having the payload climb to the top you filled the inside with 1 ATM of air and floated to the top via balloon?

There are two problems:
1. air is not massless
2. air is compressible (see http://en.wikipedia.org/wiki/Barometric_formula )
 
Friction? The Earth and space elevator rotate so as a climber ascends it must gain speed and will put sideways forces on the tower/tether.
 
udtsith said:
What would the problems be with having a hollow cylindrical space elevator made of carbon (e.g. recent benzene linked chains) and instead of having the payload climb to the top you filled the inside with 1 ATM of air and floated to the top via balloon?
As with the atmosphere outside, there would be a gradient of pressure as you go up. To have 1ATM at the top, you would need squiilions of ATM at the bottom. At best, it would be a bomb waiting to go off and at worst, it would require a fantastic input of energy to get those conditions.
 
The high pressure and low temperature would make air solid (everywhere apart from a tiny region close to the top). Hard to float up there.
Not to mention the huge amount of mass to build a tower of solid air.