This is a candidate for the Great Filter: interstellar civilizations that come into contact destroy one another.
[0] https://en.m.wikipedia.org/wiki/The_Dark_Forest
[1] https://bigthink.com/scotty-hendricks/the-dark-forest-theory...
The expanse seems “lighter” or less hard. The last book, deaths end i found to be particularly “hard sci-fi”.
Dropping a black hole, even a smallish one, into a star would seem to eliminate the central pressure needed to sustain fusion, and turn it off pretty suddenly, by astronomical timescales.
Although, it doesn't really make sense. Like a puncture in the wall of a pressure vessel, the pressure at the event horizon would be zero. It is hard to see how an accretion disc could form in pure plasma at such density. The fluid dynamics of plasma under such conditions is entirely intractable, so it is also hard to believe in any claimed solution.
But temporarily multiplying the output of a star might work just as well to eliminate a pesky alien infestation.
If I understood correctly, and that is conventional practice in calculations about black hole accretion discs, there is a great deal of nonsense published on the topic.
Compared to a Dyson sphere - which only requires a tiny, tiny, tiny fraction of the energy absorbed to build and launch the orbiting platforms that make-up the sphere.
You can "ignite" a gas-giant by maneuvering a black-hole into position inside the gas-giant, but (as far as we know) there are far more gas-giants than there are black-holes, and the distances involved are tremendous (nearest black hole: 3,000ly, nearest gas-giant: 6 to 9e-5 light-years). It just doesn't strike me as feasible or even worthwhile even if it was feasible.
Maybe as the heat-death of the universe approaches, the last band of remaining humans (don't ask) try to ignite the gas-giants to keep the lights on?
We don't build bonfires in our cars, as used to be done in steam locomotives; we oxidize carbon differently, and generate a pressure differential by entirely different means. Why should advanced aliens do things the clumsy way?
Anyway there isn't enough material in a solar system to build one. If you can get elsewhere to gather the stuff, why bother to bring it back?
Say you are a few million year old civilization and you detect radio from a civilization 100k light years away takes 500k years for you fleeting arrive. You are still millions of years ahead in technology. If you are a stagnant civilization you probably stay home cause the other side would overtake you, but then again that motivation to get to them as early as possible. In any event presumably as your fleet get closer you would have a better idea of the technology difference and can just do a U turn
The longer they go without contact, the wider their reach, and the greater their odds of contact.
We might suppose that the technology necessary to obliterate another civilization is arrived at early, and is hard to counter despite long subsequent development. Alternatively, civilizations that succeed in suppressing weaker ones eventually meet their match.
You'd need trillions of them per galaxy, but that's well within the capability of a type III civ.
It reminds me of the extra solar object detected a couple years ago that buzzed the Earth and then mysteriously ACCELERATED out of the system.
So assuming we were just detected and assuming there's a berserker in the system already (likely in an outer orbit) that would imply we have only a couple decades left.
Just to give some background, I watched that movie not realizing what it was based off of, just knowing it was a chinese sci-fi. And I remember being amazed at how big the ideas were and thinking China must have a culture of exceptional sci-fi writers. Afterwards I did some research and realized who it was.
Cixin Liu is the author and he's so good at big ideas. I can't recommend his stuff enough.
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link
Will check out the wandering earth. Thanks.
I realize there exist people who like sci-fi and think The Three Body Problem is good, but... I can’t understand what they see in it. The last 50 pages or so was at least an ok short story...
The last 50 pages of the third volume were not worth the paper.
One of the things it did really well was the idea that it takes everyone pulling in the same direction to be effective.
Civilizations would get to a level of science where they find out and even if they could reach us before the reset, there'd be no point. Like when you're playing a video game and you get "server shutdown in 30 minutes", you log off right away or mess around until it happens.
The Great Filter is only limited by our imagination and doesn't even have to involve us at all.
There's a planet that's trying to achieve peace. They're in the middle of a cold war, looking rather like earth, half hour ends with the failure of talks and a nuclear war. Camera pulls back to two alien teens playing an intergalactic arcade game, now showing "game over".
Perhaps the one playing the sim got bored and started star killing their own solar systems.