[lif]

Unpopular take, and note, I am not an expert:

There seems to be an overabundance of sci-fi that is hyperoptimistic with regard to tech advances. The 2nd law of thermodynamics is not understood by most, or waved away as 'overcome thru future science'.

fwiw, here's a few works I've found to be less the above:

book: Kim Stanley Robinson's _Aurora_

short stories: Damon Knight's _Stranger Station_ Larry Nivens' _Inconstant Moon

[Calwestjobs]

Exactly ! Just simple : Do we have any complex mechanism which works for last 100 years nonstop without fail ? Answers question of generational ships towards other solar systems. XD

[aleph_minus_one]

> Do we have any complex mechanism which works for last 100 years nonstop without fail ?

For the following examples, this question is open, and you might have a different opinion whether they fit your opinion of "complex", but the following are candidates that I am aware of:

The 10,000 Year Clock (Clock of the Long Now)

https://en.wikipedia.org/wiki/Clock_of_the_Long_Now

https://www.10000yearclock.net/index.html

The organ in the St. Burchardi church in Halberstadt (Germany) that is used to play the ORGAN²/ASLSP (As Slow as Possible) by John Cage

https://en.wikipedia.org/wiki/As_Slow_as_Possible

https://www.aslsp.org/

[Calwestjobs]

lets say they fit, but they do not work, people expect for them to work. but yes they are designed to work that long in stress free environment.

your ship needs to be repaired on the way, do you need to have repair tools, materials, for that on board ? Seafaring cargo ship can not be going 100 years without repair. I bet space ship can not go either. What if your 3d printer on board which makes your repair tools brakes... etc etc.

you "can" fly 99.99% of speed of light to get there sooner, but you smash into grain of dust and what happens? either radiation burst or explosion. space is not vacuum as a 0 particle space.

[Ukv]

> your ship needs to be repaired on the way, do you need to have repair tools, materials, for that on board ? Seafaring cargo ship can not be going 100 years without repair. I bet space ship can not go either.

Seems clear that yes, you would take tools and materials to allow for repairs, along with redundancies for any essential systems. If "your 3d printer on board which makes your repair tools brakes" you'd fix it using tools you already have available or printed out from one of your other 3D printers (even the ISS, far closer to Earth, has multiple).

It's true that creating, launching, and maintaining a generational ship would be a massive engineering undertaking, and underestimating the level of redundancy/repairs needed for some system could be what ends up causing a catastrophic issue, but the idea that we'd take zero tools for maintenance, expecting no repairs to be made at all, feels a frivolous reason to rule out generational ships.

[Sevii]

This is really a question of slack. How long can it fail for? For a 100 year mission you likely want at least a month of slack in your air supply. Things are going to break. You build in redundancy.

[rcxdude]

I mean, we have systems of government and other organizations which have lasted (significantly) longer than that. I think that's an important indicator of such questions.

[nottorp]

I wouldn't ever classify Kim Stanley Robinson as "optimistic". With maybe the lone exception of the Mars books which are at least not completely pessimistic.