Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

I don't think that it matters if the food you're importing is a luxury or a drug. People will always prefer to grow it themselves rather than importing it at a much higher cost.

By the time people are building starships, they have almost certainly already mastered O'Neil colonies and arcologies. If they don't have the natural conditions necessary to grow the luxury/cash crop, they will create artificial conditions that replicate the original environment. All they will need is some seeds (or cell-lines for cloning) and data on the growing environment.

Also, don't count out the possibility of synthetic substitutes for drugs. Unless biotech is stuck at TL8, they should be able to synthetically produce nearly any drug that a living thing can grow.


The exceptions will be newly discovered organisms that haven't been cultivated outside the colony yet, and bizarre things like Arrakeen sandworms that just cannot be cultivated at all.



Like Johnny said, exceptionally expensive manufacturing that requires enormous infrastructure is the main thing people would still want to trade.

Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

And that mostly works in the direction of colonies importing things, not exporting them, since the homeworld is ahead on infrastructure.

Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

How can you know that? Aging is poorly understood and only irregularly studied in humans. Anumal aging is even less studied partly because animals live so much shorter lives that they don't make good models for humans.

Nevertheless there are studies that claim that slowing your metabolism down by eating less will extend your lifespan. By everything I understand slowing your metabolism to 10% should slow all your metabolic processes proportionately and aging I a metabolic process.

Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

The fundamental problem with trade of that sort is what do the customers pay with? Finding something rich high tech places have that third world places want a lot isn't difficult, it's finding something with an equal value density goes the other way that's hard. If the colonies don't have something equally valuable to send home in the same number of ships, they don't have the money to buy infrastructure heavy imports with.

Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

There's considerable research on aging in animals (and even hyper-aging animal models) exactly because they have shorter lives and thus it's actually possible to run experiments on them. (Plus all the other usual problems with human experimentation.) There are a number of tricks that look pretty good for life extension in rodents, actually. Of course, whether any given approach crosses over to humans is impossible to really say without many decades of testing.
You're 'understanding' a lot more than we actually know, I think. It's very unlikely you can slow all metabolic processes at once by 90% by any means other than chronostasis.
Realistically, space colonization doesn't particularly work economically. The only things a low-development colony can reasonably buy imports with are subsidies and very-long-term credit.

Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

Exactly, and if there's no trade there's no way for people to go there which kinda makes the whole thing pointless. Plus the people who bankrolled the colony will want a return on their investment

Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

Absent TL^ stuff, colonization at these distances is always going to be a vanity project; the return on investment is the prestige you get out of its success.

Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

The simplest solution for getting the required delta-V is to just use staging.
A basic TL9 fusion rocket design (i.e. single fusion rocket engine with 13 hydrogen fuel tanks)
provides approx 250mps. Each stage burns through it's fuel in approx 2 month of continuous operation. Just stack these one over the other for whatever performance is needed.
Personally I would design this ship as a-SM11 automated cargo vessel.
It don't require exotic fuel which may be difficult to produce in a still developing colony. The craft is relatively cheap (43 mil SM9 stage, 140 SM10 stage, 430mil sm11 stage) So approx 610mil (not including hydrogen cost) for 750mps
Final stage would SM8 (4mil cost) and include a control room.
if this is a shipment from earth to another planet it would have two soft-landing systems (since destination doesn't necessarily have infra to go get the shipment from orbit) and contains 850 tons of cargo.
That's a shipment cost of less than 1mil per ton of cargo. (we pay more than that to launch to low earth orbit).

Hope this helps
Adi

Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

If you take a long enough view and have very limited domestic growth options, that doesn't have to be so.

Re: [Space/Spaceships] Getting the velocity/Delta V I want with the tech I want
 

True, but in that case it's likely that you're okay with a 40 year transit time instead of a 4 year transit time, and that reduces the energy budgets by a factor of 100.