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Biggest void in space is 1B light years across (2007)

newscientist.com

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Re: Biggest void in space is 1B light years across (2007)

#61

Post by deepsun »

phaedrus wrote: post #29
mmazing wrote: post #13

Imagine being a civilization on the edge of a galaxy on the edge of the void. One direction, nothing whatsoever. The other direction, billions upon billions of galaxies. Would be neat!

Imagine being a civilization alone in the void, and not even a generation ship could make contact with anyone else, even if they knew which direction to send it.

Well, even one galaxy is too big for anyone. As one astronomer said, even one local arm of Milky Way is enough to fit all and every science fiction ever imagined. There's just too much stuff, that you don't need to think about other galaxies.

Re: Biggest void in space is 1B light years across (2007)

#62

Post by ncmncm »

michaelmrose wrote: post #42
ncmncm wrote: post #27

Earlier quoted context omitted.

The whole concept of Dyson Spheres, or anything even vaguely like that, is totally absurd. (Even Dyson said so.) Any space-faring culture will have mastered controlled fusion long ago, and have entirely left behind any material dependence on stars. The best places to live, then, are out in the Kuiper belts and beyond, where unlimited room and cold are available for free, and valuable gases are lying about, frozen. In…

>Expanding menace civilizations will run up against overwhelmingly more advanced stable cultures before long and be contained or destroyed, so odds are none could get here before that happens. This seems like an interesting thought experiment care to expand on that?

An expanding menace culture will also be young, just because anything growing fast can't have been doing it for long. By comparison, a stable culture can stay that way indefinitely, spending its resources accumulating knowledge and skills instead of on expanding, and so can accumulate a very great deal of both over a vast stretch of time. It has perhaps less access to materials, but a solar system has a great deal of material to start with, and it is not stretched thin.

When an expanding menace tries to absorb the ancient stable culture, it has key disadvantages. Its attention is spread over activities on a large periphery, and its stores of knowledge and weaponry are limited. The ancient culture has been found by many menaces before, and survived them all. It knows of other old, stable societies, and they may even have evolved a common plan for dealing with menaces.

It is conceivable that the expanding menace would try to flow around the old stable societies, like a river around rocks, without threatening them enough to provoke a backlash, but that runs against the logic of expansion.

So, odds are any expanding menace will encounter one of them, or more than one, if needed, before it gets to us. Each such encounter will be an existential challenge at bad odds, which multiply out increasingly close to zero.

Thus, the stable condition of a galaxy is a sparsely occupied archipelago of deeply ancient, unassailable cultures not interested in expansion, so not visiting, e.g., us, with the occasional rash of menace, dealt with firmly.

Re: Biggest void in space is 1B light years across (2007)

#63

Post by ncmncm »

m4rtink wrote: post #35
ncmncm wrote: post #27

Earlier quoted context omitted.

The whole concept of Dyson Spheres, or anything even vaguely like that, is totally absurd. (Even Dyson said so.) Any space-faring culture will have mastered controlled fusion long ago, and have entirely left behind any material dependence on stars. The best places to live, then, are out in the Kuiper belts and beyond, where unlimited room and cold are available for free, and valuable gases are lying about, frozen. In…

Unless you can harvest interstellar medium at scale stars are where most mass is locked up, conveniently in a single place even. Outer belt objects are quite small in volume in comparison and inconveniently far from each other.

The outer belt objects are small compared to planets, but are enormous considered as extracted volume, and uncountably numerous; whereas on inner planets you are effectively limited to the solidified skin at the bottom of an annoying gravity well, bathed in heat that must be shed.

Kuiper belt distances are inconvenient only when you are in a hurry and have limited speeds. Given fusion propulsion, nothing inside a solar system is especially far from anything else. But a large volume to operate in, which grows as r^3, is valuable, and an unlimited sink of cold, moreso.

If you need more mass, Neptune is right there.

Re: Biggest void in space is 1B light years across (2007)

#64

Post by michaelmrose »

ncmncm wrote: post #62
michaelmrose wrote: post #42

Earlier quoted context omitted.

>Expanding menace civilizations will run up against overwhelmingly more advanced stable cultures before long and be contained or destroyed, so odds are none could get here before that happens. This seems like an interesting thought experiment care to expand on that?

An expanding menace culture will also be young, just because anything growing fast can't have been doing it for long. By comparison, a stable culture can stay that way indefinitely, spending its resources accumulating knowledge and skills instead of on expanding, and so can accumulate a very great deal of both over a vast stretch of time. It has perhaps less access to materials, but a solar system has a great deal of…

Are you arguing that the expanding menace culture must be young because such cultures wouldn't last long because of conflict? I think a lot depends on how densely populated the universe is. At a limit imagine one long lived intelligence per galaxy. You could have a poisonous disease the size of a galaxy 10 million years old sending out spores to poison adjacent galaxies. Maybe we are even the present genesis of this.

As you adjust down you could trivially and likely have tens of light years between cultures or even hundreds on average if intelligent cultures are short lived or particularly rare. Expanding menaces could be automated and self replicating and designed to create an expanding zone of safety for an old stable society in a way that isn't easily traceable to the old stable society.

Re: Biggest void in space is 1B light years across (2007)

#65

Post by YeGoblynQueenne »

nmcveity wrote: post #31
sharkweek wrote: post #30

Earlier quoted context omitted.

Sounds like you have a sci-fi novel to write!

https://en.wikipedia.org/wiki/Against_a_Dark_Background Paints a bleak picture of a civilization in this situation. Great book though.

Came here to look for this comment :)

Re: Biggest void in space is 1B light years across (2007)

#66

Post by ncmncm »

michaelmrose wrote: post #64
ncmncm wrote: post #62

Earlier quoted context omitted.

An expanding menace culture will also be young, just because anything growing fast can't have been doing it for long. By comparison, a stable culture can stay that way indefinitely, spending its resources accumulating knowledge and skills instead of on expanding, and so can accumulate a very great deal of both over a vast stretch of time. It has perhaps less access to materials, but a solar system has a great deal of…

Are you arguing that the expanding menace culture must be young because such cultures wouldn't last long because of conflict? I think a lot depends on how densely populated the universe is. At a limit imagine one long lived intelligence per galaxy. You could have a poisonous disease the size of a galaxy 10 million years old sending out spores to poison adjacent galaxies. Maybe we are even the present genesis of this.…

> "Are you arguing that the expanding menace culture must be young because such cultures wouldn't last long because of conflict?"

It's young because it's expanding. To first order, divide the radius by the rate of expansion and you get when it started. The society that bides its time for millions of years and then turns menace does not pass the smell test. Every year they go without menacing, the less likely they ever will.

Anyway, whoever's (1) inside the perimeter, (2) is a bad trading partner, and (3) not burnt is a pretty good bet for who's responsible. If there are two plausible candidates, they are better both dealt with.

It's also true that they don't last long because of conflict, but that's secondary.

A sorcerer's apprentice scenario is conceivable only in the short term. To maintain expansion demands adaptation to an increasing variety of new challenges, whose variety and strength increase as the fourth power of expansion radius. (Three dimensions for space, one for age of opponent.)

One can invent myriad obscure scenarios, of decreasing likelihood. It's a big universe, rashes happen, but it's a big universe, so they mostly happen somewhere else.

Re: Biggest void in space is 1B light years across (2007)

#67

Post by ncmncm »

m4rtink wrote: post #35
ncmncm wrote: post #27

Earlier quoted context omitted.

The whole concept of Dyson Spheres, or anything even vaguely like that, is totally absurd. (Even Dyson said so.) Any space-faring culture will have mastered controlled fusion long ago, and have entirely left behind any material dependence on stars. The best places to live, then, are out in the Kuiper belts and beyond, where unlimited room and cold are available for free, and valuable gases are lying about, frozen. In…

Unless you can harvest interstellar medium at scale stars are where most mass is locked up, conveniently in a single place even. Outer belt objects are quite small in volume in comparison and inconveniently far from each other.

To add, we are only just beginning to experience a hint of the plague of excess exhaust heat. It only gets worse, and the Third Law of Thermodynamics is a harsh mistress.

Re: Biggest void in space is 1B light years across (2007)

#68

Post by serf »

ncmncm wrote: post #62
michaelmrose wrote: post #42

Earlier quoted context omitted.

>Expanding menace civilizations will run up against overwhelmingly more advanced stable cultures before long and be contained or destroyed, so odds are none could get here before that happens. This seems like an interesting thought experiment care to expand on that?

An expanding menace culture will also be young, just because anything growing fast can't have been doing it for long. By comparison, a stable culture can stay that way indefinitely, spending its resources accumulating knowledge and skills instead of on expanding, and so can accumulate a very great deal of both over a vast stretch of time. It has perhaps less access to materials, but a solar system has a great deal of…

this is an interesting observation, and it plays out exactly like this many times over in the 'Stellaris' RTS game.

Stable societies that stick to their own region while prioritizing research ('growing tall' is the name for the strategy) tend to win out in battles against those that 'grow wide', grabbing all resources and expanding into them with little regard to research and personal affairs.

Those that 'grow wide' tend to win the games through simple attrition on a long time-span at the end-game phase. Simple resource volume tends to be able to win against vastly superior forces, much like a StarCraft 'zerg-rush', and the superior force usually loses in a 'death by a thousand cuts' fashion -- but individual battles before this phase of the end-game are almost exclusively won by small civilizations that 'grow tall', much like the 'stable culture' of your example.

The 'Growing Tall' strategy tends to be the one chosen by players who like to end games early and play aggressively against the other players -- contrary to the sedentary and passive method of play that the strategy facilitates.

Re: Biggest void in space is 1B light years across (2007)

#69

Post by ncmncm »

serf wrote: post #68
ncmncm wrote: post #62

Earlier quoted context omitted.

An expanding menace culture will also be young, just because anything growing fast can't have been doing it for long. By comparison, a stable culture can stay that way indefinitely, spending its resources accumulating knowledge and skills instead of on expanding, and so can accumulate a very great deal of both over a vast stretch of time. It has perhaps less access to materials, but a solar system has a great deal of…

this is an interesting observation, and it plays out exactly like this many times over in the 'Stellaris' RTS game. Stable societies that stick to their own region while prioritizing research ('growing tall' is the name for the strategy) tend to win out in battles against those that 'grow wide', grabbing all resources and expanding into them with little regard to research and personal affairs. Those that 'grow wide'…

In Stellaris, everybody starts at the same time, right? And, close enough together that they are sure to encounter one another pretty early? And, material resources actually matter?

It seems like being equipped to, say, cause a solar flare to sterilize an offending planet would tend to discourage an aggressor before their ships got used up. Probably a flare wiping out a neighboring planet (e.g. one like Venus) first would convey the message adequately.

Re: Biggest void in space is 1B light years across (2007)

#70

Post by m4rtink »

ncmncm wrote: post #67
m4rtink wrote: post #35

Earlier quoted context omitted.

Unless you can harvest interstellar medium at scale stars are where most mass is locked up, conveniently in a single place even. Outer belt objects are quite small in volume in comparison and inconveniently far from each other.

To add, we are only just beginning to experience a hint of the plague of excess exhaust heat. It only gets worse, and the Third Law of Thermodynamics is a harsh mistress.

Well, for how bad it can get one can check Puppeteers home world in Nivens Known Space universe - that damn planet shines white in visible spectrum in many places due to waste heat and they indeed had to move it farther from their sun.
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