86

We can examine what a full K-type "difference" looks like in the current context. While we cannot look up yet (there are no K-type 1.7+ civilizations as far as we can see), but we can look down. Humanity is K-type 0.7 as of 1973, and since then has added rounding error. So we are talking about what a modern industrial war looks like to a K-type -0.3 ...


47

Do rats care about human war? Other answers have focused on powerlessness and how the Ⅱs may be accidently trampled by the Ⅲs, as (Zibbobz points out) like the source of the expression of mice and men. But I want to focus on the idea that this presents a background that’s no different than any uncontrollable nature. The rats avoid the battles, and then ...


42

The easiest Problem to deal with is quite simple: they're wrong. A civilization like that presumably has some direction they believe they are going along. They're hopefully not just wandering aimlessly among the stars, using up the full energy of a galaxy here and there. They have to have some plan that's guiding them. What if that plan is wrong? What ...


34

The best the KII civilization can do is to attempt to shield themselves from collateral damage caused by whatever the aliens are using. This is problematic since they could be using principles and physics which have not even been discovered yet by the KII civilization. In that regard, the question is somewhat like asking what effective steps Knights could ...


31

Isolation and collapse to Kardashev Level 2 Civilization If current theories about the Universe, Dark Matter, and Dark Energy are correct; then we're beginning a period of ever increasing acceleration of objects away from each other. What this means is in the future, galaxies accelerate away from us so that they fall outside our light-cone. Eventually we ...


29

A Kardeshev Type II civilization capable of transitioning to a Kardeshev Type III should no longer be bound to a particular planet or even a single solar system. They should already be able to move populations from world to world with little effort having already mastered the ability to harness energy from thousands or even millions of stars in their ...


29

Stagnation An understanding that as they're no longer challenged they're no longer changing. As they're no longer changing, they're no longer evolving. Like the old tree, their civilisation is rotting from the inside out and will in due time collapse under its own weight, leaving the space for the smaller civilisations to take their place in the universe. ...


25

The Foo are, simply, boring. Extending the forest analogy, the Foo are the towering redwoods, the biggest, best thing around. As time goes on, the trees just keep growing; while at first they reach towards the heavens, eons later they are surrounding entire suns to capture the energy. A Dyson sphere, after all, is at its soul merely a really efficient tree - ...


22

Here is some perspective. Human power consumption is 1.23e13 W or 3.87e20 J/year. An 1 Megaton nuclear weapon goes pop with 4.2e15 J of energy, or 5 orders of magnitude less than our yearly consumption. A type III civilization can harness the power output of a galaxy, or 4e37 W = 1.3e45 J / year. At the same ratio of power, an alien super-weapon would hit ...


20

This is not a reasonable depiction of a Dyson Sphere. First of all, it must be stated that this kind of Dyson Sphere - a solid "Dyson Shell" - while a popular description, is universally regarded as unrealistic by serious writers, even in the context of a civilization capable of building solar system sized megastructures. Even if the absurd amounts of ...


15

What is missing is parsing the requirement accurately. Type II definition includes "capable of utilizing and channeling the entire radiation output of its star", and then continues to discuss the energy utilization. This does not require actually capturing all solar radiation of their star. For example, we could harness the equivalent energy to all ...


14

While I admire the Foo civilization, I do pity the individual Foo. As you describe, they already have achieved everything. What's left to do? Nothing. So, with such a context, how to fill your life? I predict lethargy will take over. Turning into depression all too often. That means major effort will go into recreational drugs and gaming. And that real ...


14

Inferiority Complex It strikes me that the main issue that such a vastly advanced race could face (one that would require the immediate construction of an entire artificial universe in order to come up with some truly "out of the box" thinking) is that they suddenly learned that they were trapped inside a box. Let's say that your Foo scientists are ...


12

The most logical explanation that springs to mind for me is that a Dyson Sphere or Dyson Swarm is not something you can build overnight. It's a gigastructure far beyond anything humanity would have constructed up to that point. Even with your futuristic technology, I wager it would take years, if not decades, to build. Now, that wouldn't be enough to put ...


12

Basically, you're asking how to suck the heat out of a while dwarf without sucking all the mass out. That's really hard. The classic three methods of heat transport are radiation, convection, and conduction. A white dwarf already emits essentially all of the radiation it can from its surface, so there's not much more you can do with radiation, other than ...


11

My intuition is that they will not. A Type II civilization would be able to get fusion energy, information, and raw-materials from multiple solar systems; it is capable of evolutionary intervention, interstellar travel, interstellar communication, stellar engineering, terraforming, star cluster-scale influence and can be expected to be so within 1000 to ...


11

Perhaps your best source here is the recent Ribas, Bouy, and Merín 2015 paper, distinguishing between primitive and processed disks by the mass of the stellar object. The take home point seems to be that larger stars tend to process or blow away their disks relatively quickly. The actual N-body dynamics you describe (two stars and a granular disk) are ...


11

I've spent a good deal of time thinking about this and related problems. The puzzle caused by the multidimensional linkages between growth and technological progress has been a difficult one to crack. You can look up the giants in the field of growth, such as Solow, Ramsey, Simon, Harrod, as well as the New Growth Theory. Production Possibilities Frontier ...


11

Ennui. The disaster is millions of years in the making, but for a civilization that has lived billions, it's as nothing. People have conquered every challenge available. They turn inward. Population growth is negative because nobody cares to do anything about it. War spreads as a means of entertainment. Even that grows old and the survivors give up. ...


10

I decided to start working on my own answer after I asked the question, so here's the result of a few days' work. An excellent (and very recent) paper regarding accretion is Debnath (2015), which can be applicable at least for material gathered onto the surface of the red dwarf. Debnath assumes a static1, spherically symmetric metric: $$ds^2=-A(r)dt^2+\...


10

New answer for the added questions Would it indeed be possible to travel across the Milky Way in a single lifetime, if you were willing to forsake friends and family? This is straight forward math. We know that the speed needed will be quite close to 1c. So we need the length we are traveling to be one that light will cross in a single lifetime. The ...


10

I had written up a long spiel that was going to be part of a long answer to another question, but it looks like it'll do all right here. Just so you don't think that I whipped it up in 20 minutes. Type Ia supernova Let me take a detour to look at this. In a Type Ia supernova, we would need a second degenerate body, typically a white dwarf. The first issue ...


9

Ok, I'll bite. If all you got in the area is a big cloud, mostly Hydrogen, with teensy amounts of heavies scattered about, and you're getting chilly, or wanna cook s'mores, and you need a New Star there toot sweet, as Granny Ogg would say, what can you do? Above: Very Rude Nebula. Basically asking to be subjected to some serious fusion. You could blow up (...


9

A Dyson sphere is something that would be built over the course of quite a while. It would probably start as a ring around the Sun that just keeps getting bigger as energy needs go up. It would also be using up most if not all of the extra-solar matter in the solar system in order to create this. There would be plenty of habitat area on the pieces in ...


9

As already stated in another answer, the Kardashev scale was interpolated by Carl Sagan to admit non-integer values. The formula would be the following: In this formula, K is the Kardashev's rating and P is the power the civilization uses, in Watts. This actually means that we could rate whatever civilization we want: the power will never be negative, so ...


9

Disassembling and reassembling the star The surface of a star is where all the energy gets out by radiation. In a regular sphere that is $4 \pi r²$, but it's volume $\frac{4}{3} \pi r³$ implying a surface-volume-ratio of $\frac{3}{r}$. With $r=0.0038 R_{solar} = 2643.66 km$ you'd have a ratio of $1.13479 \times 10^{-6} \frac{m²}{m³}$. If you were to change ...


8

As mentioned in the article, Kardashev does not have to be discrete. Sagan provided a formula so that the Kardashev Scale is continuously defined. On that scale, present-day Earth comes out as a 0.7 civilization. Sagan also proposed pairing that numerical value with a letter to indicate the cumulative information content of a civilization. If I remember ...


8

Here are my R calculation results. The first two columns are fractions (and multiples!!!) of $c$. Effect.Veloc.Astronaut Starship.veloc.stationary Joules.100000.kg.ship 0.01 0.01 4.50E+17 0.1 0.0995 4.50E+19 0.2 0.196 1.80E+20 0.5 ...


8

What could cause an nearly omnipotent race to need an out-of-the-box solution? A bet with another omnipotent race, of course. Suppose two such races are fighting. Instead of bombing one another, they pose each other challenge problems. If a problem cannot be solved, one race wins. The wars would last ages in human terms. The challenges would be beyond the ...


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