Science

Homeopathic solutions to the Fermi paradox

Homeopathy: for those who have never learned the details, claims that the potency of a treatment can be increased by repeatedly diluting it. There are many scales — the C-scale is “how many times has this been diluted by a factor of 100”, the X-scale “…by a factor of 10”. I’d say “clearly nonsense”, but I fell for it when I was a teenager.

Fermi paradox: there are so many stars in the observable universe — tens of sextillions (short scale) — that even fairly pessimistic assumptions imply we should be surrounded by noisy aliens… so why can’t we see any?

One of the most common resolutions to the Fermi paradox is that there are one or more “great filters” which make it entirely unlikely that any of those stars have produced intergalactic expansionist civilisations. There are good reasons to expect direct intergalactic expansion rather than starting with ‘mere’ interstellar expansion, and (rather more surprisingly) good reasons to think we’re within spitting distance of the technology required, but that only makes the non-technological problems all the more severe. There are a lot of unknowns here, obviously we’ve only got ourselves as an example, so the space between “where we are now” and “owning the universe” is filled entirely with underpants gnomes, and that’s where homeopathy fits in, in two separate ways.

First, as a categorical example. Homeopathy represents an archaic way of thinking, yet it’s very popular. It’s simple, it’s friendly, it is a viral meme. There are many of these, some of them are quite destructive, and while it’s nice to think nature is in a balance — especially when we’re thinking of something we’re really proud of such as our own minds — the truth is nature (including humans) often goes off the deep end and only sometimes recovers. It’s very easy for me to believe that an anti-rational meme such as homeopathy can either destroy a civilisation entirely, or prevent it developing into a proper space-faring civilisation.

Second, as an analogy. Dilution. It’s not the first dilution of a homeopathic preparation which removes all atoms of active ingredients from the result, but the repeated dilution. If there are, say, twenty things which have an independent 50% chance of holding back or wiping out a civilisation out before it can set up a colony — AI; bioweapons; cyber-warfare; global climate change (doesn’t matter if artificial warming or natural ice age); cascade agricultural collapse; mineral resource exhaustion; grey goo; global thermonuclear war; cosmic threats collectively from noisy stars whose CMEs make electricity impractical to asteroids and gamma ray bursts; anti-intellectualism movements, whether deliberate or not; feedback between cheap genetic engineering and genetically-defined super-stimulus making all the citizens a biologically vulnerable monoculture … — twenty items each with a 50% chance adds up to million-to-one odds (million-ish, but if you care about the difference you’re taking the wrong lesson from this).

Yes, one-million-to-one is almost irrelevant compared to ten sextillion. Odds of (100e9)^2-to-one would require 73 such events, not 20, but this combines with the previous Fermi estimates, it doesn’t replace them. 20 such events reduces the overall problem by a factor of a million, no matter what your previous estimate was, and both 20 events and 50% chances are just round numbers, not a real ones. Unfortunately, we don’t know how many small-filters we might face: as the Great Recession was starting, someone said that no two recessions are the same because we learn from all our mistakes and so each mistake has to be a new one. Sadly it’s worse even than that, as humanity as a whole does repeat even its economic mistakes, so even if we weren’t re-rolling some of our previously-successful dice because we keep thinking “we’re too big to fail“, humans don’t know all the ways we can fail to survive.

The Great Filter doesn’t have to be something that civilisations encounter exactly once and in much the same way a sentence encounters a full stop — it can be the death of a thousand paper-cuts.

If we do finally reach the stars, we may find the universe is much more interesting than it currently seems. Instead of Vulcans and warp drive, we might find hippy space-elves communing with their trees via mind-warping drugs… and if we don’t, instead of wiping ourselves out, we might become the hippy space-elves that some sentient octopus discovers while going boldly where no sentient octopus has gone before.

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Futurology, Technology

Hyperloop’s secondary purposes

I can’t believe it took me this long (and until watching this video my Isaac Arthur) to realise that Hyperloop is a tech demo for a Launch loop.

I (along with many others) had realised the stated reason for the related–but–separate The Boring Company was silly. My first thought for that was it was a way to get a lot of people underground for a lot of the time, which would reduce the fatalities from a nuclear war. Other people had the much better observation that experience with tunnelling is absolutely vital for any space colony. (It may be notable that BFR is the same diameter as the SpaceX/TBC test tunnel, or it may just be coincidence).

A similar argument applies to Hyperloop as to TBC: Hyperloop is a better normal-circumstances transport system than cars and roads when colonising a new planet.

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Science, SciFi, Technology

Kessler-resistant real-life force-fields?

Idle thought at this stage.

The Kessler syndrome (also called the Kessler effect, collisional cascading or ablation cascade), proposed by the NASA scientist Donald J. Kessler in 1978, is a scenario in which the density of objects in low earth orbit (LEO) is high enough that collisions between objects could cause a cascade where each collision generates space debris that increases the likelihood of further collisions.

Kessler syndrome, Wikipedia

If all objects in Earth orbit were required to have an electrical charge (all negative, let’s say), how strong would that charge have to be to prevent collisions?

Also, how long would they remain charged, given the ionosphere, solar wind, Van Allen belts, etc?

Also, how do you apply charge to space junk already present? Rely on it picking up charge when it collides with new objects? Or is it possible to use an electron gun to charge them from a distance? And if so, what’s the trade-off between beam voltage, distance, and maximum charge (presumably shape dependent)?

And if you can apply charge remotely, is this even the best way to deal with them, rather than collecting them all in a large net and de-orbiting them?

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Futurology, Technology

Musk City, Antarctica

One of the criticisms of a Mars colony is that Antarctica is more hospitable in literally every regard (you might argue that the 6-month day and the 6-month night makes it less hospitable, to which I would reply that light bulbs exist and you’d need light bulbs all year round on Mars to avoid SAD-like symptoms).

I’ve just realised the 2017 BFR will be able to get you anywhere in Antarctica, from any launch site on Earth, in no more than 45 minutes, at the cost of long-distance economy passenger flights, and that the Mars plan involves making fuel and oxidiser out of atmospheric CO₂ and frozen water ice so no infrastructure needs to be shipped conventionally before the first landing.

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Space rockets are Big.

Those quaint little pictures that show them next to Nelson’s Column or the Eiffel Tower don’t do them justice, partly because… well. I didn’t even realise how big the Eiffel Tower is until I visited it a few years ago.

So, here’s what the first stage of the SpaceX Falcon 9 rocket looks like, next to Nelson’s Column. Take a close look at the bottom, both photos have people in them.

Falcon 9.jpg

The image of Nelson’s Column [linked here] is licensed as Creative Commons Share Alike, which requires that “If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original.”

Fortunately, the image from SpaceX [link] was licensed as CC0 1.0 Universal (CC0 1.0) Public Domain Dedication, which doesn’t interfere with my ability to release this as CC-SA-3.

Science, Technology

Falcon 9 to scale

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