Google kind of sucks. I am curious about how close to the speed of light we can get (in a spaceship for instance). We're not even close to 0.01c as things stand, but I have many questions: are there engineering reasons to believe we will/won't get to p*c for any p? What tech is being proposed/ruled out etc. no matter what I search, google shows me things like "why can't we/what would happen if we go faster than light?" and all sorts of intro stuff that I already know.

I think (correct me if I am wrong) that google is trying to guess what I might want to know based on data about me, based on what similar people who made similar searches eventually clicked on, etc. etc. rather than the pure output of a pagerank type algorithm. But that's very annoying because I have some specific question that a general audience wouldn't necessarily think to ask.

@ccppurcell
Fair point and I also noticed this (it's been getting much worse since about 2015).
Nowadays I mostly use Google as frontend for some forums, and simply read through the sources lists on Wikipedia (which is certainly slower and yet, somewhat ironically, more time efficient (if I can avoid getting distracted by the looming tendency to wiki-walk))

@ccppurcell I really really miss the kind of early-2000s-era search that gave you what you were searching for, not what it thought you might be searching for instead.

@jsiehler I feel like I genuinely developed some useful "googling" skills that are almost totally useless now.

@ccppurcell Bussard ramjets could get to 12% of c, but that’s future tech that still needs to be invented. IIRC an Orion drive could reach somewhere in the realm of 10% of c (that’s using nuclear fission bombs to accelerate a ship), although I could be thinking of project Icarus/Daedalus which uses fusion of deuterium pellets.

@j thanks! This is exactly the sort of thing I wanted to read about/think about.

If you feel like answering another question of mine: is the discovery of water on a habitable zone planet significant for people interested in space colonization? It's 124 light years away, to get there within 40 years (already stretching the imagination of human endurance) would mean going about 0.95c

@ccppurcell I don't believe so. If you can manage the energy requirements to travel at 0.95c, you can probably manage to build self sustaining space colonies. A rotating habitat, if sufficiently large, gives far more living space per kg than a planet.

That's not even getting into the ideas of mind uploading, virtual realties and matrioshka brains. Mind uploading, for instance, alongside improvements in computers, enabled travelling at even higher velocities—you can ditch all the meat.

@j That is a good point... do you mean rotating habitat as in using centrifugal force to simulate gravity?

@ccppurcell Yup. An extreme (and unstable) example would be ringworld. A less extreme (but still physically... difficult to achieve) would be a Culture Orbital.

If it's big enough, the coriolis force should be unnoticeable.

@j Right, like Enders Game (although if I remember correctly it's implied that in fact they are using hive queen antigravity technology and the rotation is just for show... or something)

@ccppurcell It's a common sci-fi trope for a reason: It's physically sound. Rendezvous with Rama would be my preferred example, if I'm talking about hard sci-fi. The Expanse (both book and TV series) is worth checking out too.

@j it's going on my (ever growing) reading list, thanks :)

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