quote: For example, page 307 in Singularity is near says: Lets consider where we are, circa early 2030. We ve eliminated
the heart, lungs, red and white blood cells, platelets, pancreas, kidneys, bladder, liver and more..
Page 303: Redesigning the digestive system, reasonable mature by late 2020s.-andmar74
The problem I see with singularity is near is that it assumes hard nano not only is feasible, but that it can work outside of specialized environments in manufacturing or research facilities.
IMHO, it is likely that soft nano is the only nano that is viable in a wide number of real world environments. Unless you design hard nano with a similar ease of dis-assembly and repair of components, it will have serious trouble dealing with failure of an internal component, let alone multiple components. I find it highly unlikely that energy extraction, constant high speed motion, and bombardment with external agents*(high energy particles, especially in outer-space) can be withstood for long periods of time without failure of some internal component. A biological cell can withstand countless multiple simultaneous failures of its internal components at the same time, how many can hard nanobot designs withstand before becoming nonfunctional? in case of becoming nonfunctional how easy is the dis-assembly and repair? The answers to these two questions will determine viability.
That said it is indeed likely that at least soft nano will be used to replace all of our internal organs with far superior versions. Endogenous synthesis of all vitamins, and countless beneficial compounds will occur. Long term storage of excess necessary trace elements to withstand possible suboptimal nutrition, and the ability to tolerate toxic amounts of these substances by storing some and mass disposing of unnecessary excess. Also vast detoxification capabilities for poisons, the ability to withstand prolonged oxygen deprivation without damage, higher radiation tolerance, and cancer immunity with agelessness, and vast scar free regenerative potential.
IIRC, the idea of cartridges, belts or something like that was mentioned to deal with waste and provide raw materials and nutrients, this can possibly be accomplished with soft nano too.
Theoretically a linking system towards the blood supply could be designed, with a safe plug-n-play design, that would connect the body to an external machine that could provide nutrients and take waste materials and recycle them externally while using a computer or vr technology.
IF fusion reactors can be built and miniaturized or alternatively using wireless electricity, wastes would not need to go outside the body as there would be sufficient energy to internally recycle all internal waste produced and digest 100% all food, there would be enough energy to transform excesses into anything... say flowers? Though with the advent of augmented reality food, excess consumption is unlikely.
Way I see it is likely that nutrient and waste exchange will occur while asleep, or if we do away with sleep while sitting or relaxing some, through a plug-n-play wire or if desired cartridge system, though plug-n-play wire seems less cumbersome.
Augmented reality food will dispense with most need for managing digestive waste, and aided by a system that harnesses either wireless electricity or nuclear fusion(less likely) it should be possible to handle real food without producing nonpleasant waste. Wireless electricity would also allow for sufficient energy to recycle all internal wastes.