james_nicoll

I've read a few stories along the lines of A; to get the necessary elements for people's bodies to function, you'd use bioacumulation. Plants absorb trace amounts of metals from the soil; humans burn those plants and spread their ash in one tiny plot of land. Humans defecate and bury their bodies in that same plot of land, and gradually the amount of arable land with Earth-normal composition grows. Not mentioned is the fact that nasty heavy-metal elements would also bioaccumlate this way.

In the dream there was a metal poor world orbiting what in my dream was Proxima Centauri - dur - but more plausibly Barnard's Star (since it, unlike Proxima, is actually metal poor [1]), which as far as anyone knew was passed over for settlement because of the metals issue. Except as it turned out, people were living there somehow, overlooked because nobody thought to double check.


1: Unless in my dream Proxima turned out not to be part of the Alpha Centauri system. I don't think its metalicity is directly known, is it?

In the dream, this was roughly on par with discovering a community of Sivullirmiut living undetected in, oh, modern day Nova Scotia.

If a society can engineer plants to accumulate Useful Metals - whatever those are deemed to be - to be concentrated in the populated areas, presumably they can also engineer plants to accumulate Nasty Metals, which would then be hauled out away from the human zones.

The logic behind the plant haulage scheme might well escape later generations...

An interesting plot point. The genetically-engineered MethylMercury tree is beautiful, and its widespread, probing roots prevent soil erosion. Sadly, its fruit are so foul-tasting that they are inedible. By a strange coincidence, odd patterns on the skin of the fruit look like a cartoon person going "YUCK!". Its fruit also give off such a disgusting, persistant smell that you have to stuff them in the deep Caves of HazMat just to keep the area pleasant.

Someone decides that, rather than spend time hauling away all the nasty fruit, it would be easier to chop down the trees. Neurotoxicity ensues.

One of the myriad of things in tMiGE that would need to be 'fixed.' That one bugged me since I was a teen though. Along with the whole "the moties went across normal space at 7% of the speed of light! That's something that the 1st Empire couldn't do! And we're their inferiors! But wait! We just accelerated and decelerated from that speed twice without blinking twice in the space of x tens of hours!"

oy.

Like I said lots to fix.

In Richard McEnroe's Far Stars and Future Times, the tramp star ships have photon drives. A lot of the plot has to do with a WMD but nobody seems that concerned about the fact the photon drive itself isn't anything you really want lit off over an inhabited planet (although ISTR they headed out over sea before turning it on).

For people not up on photon drives: the power they need is

P= FC, where F is force and C is the speed of light.

Take a 100 tonne ship accelerating at 10 ms/s/s: that's 300 terawatts or about 20x the power all human civilization generates today or to put it another way, I think it's about five Hiroshimas per second.

If you lit off that kind of drive in an atmosphere, you'd rapidly find yourself inside something the equivalent of an expanded nuclear fireball. Maybe their vehicle has a good A/C system.

at 7% of the speed of light, how many Hiroshima's would be released by just slaming the engine into the planet?

I remember a space opera where the missles were 'disarmed' and allowed to harmlessly impact the planet's atmosphere. About half a chapter before it was noted that the missles weighed tones and were travelling at 10% c. Everybody was so thankful to the captain of the defending ship for such an eligant solution that didn't require expending any ordinance to blow them up in space.

Huh. If I have not messed up the mental math, here's a useful coincidence: at 7% C, each kilogram has a kinetic energy of roughly a kiloton.

IE If the Saurons were really losing, relativistic battle wagons are likely to have been launched at the enemy at some point. Sure, it'd be some time before they arrived, but...

Sparta gets splatted is another example of where tMiGE needs to be fixed then.

I believe the formula is correct, at least. I kept thinking the units were wrong, but it was because I persisted in reading P as momentum (it's usually written p, but then you've capitalized the c).

Upon reflection, wasn't it a meta plot point in known space that fusion drives were excellent weapons and it helped thump the Kzinti?

Was that the Kzin lesson? Named after the time a Kzin warship tried to take a human craft their telepath assured them had no weapons and the humans remembered their drive was a big old laser?

I don't recall. However, I do find it amusing that is the case. If the fusion drives are as powerful as calculated, then they ought to be pointing their fusion drives at each other rather than bothering with nukes or even the lasers mentioned. Single digit terawatt lasers are still a fraction of what a 300 TW fusion beam ought to be...