Game theory, applied to aliens - Page 15

On January 07 2012 23:22 Sbuiko wrote:
The problem i have with this scenario is, that the starting conditions have been skewed to make a point. So here just a few counterpoints off the top of my head:

Precision:

The precision needed to hit a tiny planet like earth from several light years afar with an object moving at speeds unbeknown to natural stelar objects are not reachable by current technologies. in flight adjustments to the flight pattern would be needed, exorbitantly increasing energy requirements for these projectile weapons. The chance of being aggressive, but not actually destroying anything are high, and then retaliation becomes possible, destroying the basic premiss of the proposed dilemma.

Proposal of nuclear-powered near light speed flight:

The theory to use such crafts do exist, and conventional chain explosion drives have been used in space probes. The problem with nuclear ones is, that they need a shield that is nuclear explosion proof (or something that absorbs the explosion, like large materials that crumble away with each explosion). In addition, the actual projectile needs to be of a high density, to sustain constant rocking and compression from the sudden accelerations. So a largish piece of concrete would simply crumble into dust, while a steel-cube might be more useful, but immensely costly to produce. Meanwhile future acceleration steps (A-Bombs) need to be completely shielded from all explosions, as they're highly delicate machines. In addition, nuclear bombs disable themselves trough radiating away their explosives over time. As such a rocket would travel several hundreds of years at least, the bombs would need to be assembled on board(!). Of course one could use smaller explosions, or use less energy for each explosion, but that increases the acceleration time, decreases total speed, and makes the premise of these attacks being undiscoverable and non-defendable doubtful.

Our current or near future world building one of these things:

Our only acceleration method would be nuclear chain bombs, as described above. The projectile can be small-ish (in stelar measures), but then we'd need to built nuclear production facilities on the projectile itself. We also need to ship several hundreds or thousands of the current yearly uran production from earth to space, and rockets have quite a high failure rate. Fall-out from an exploding nuclear transport rocket is catastrophic immediately, while the gains of the stelar projectile are highly hypothetical. That skews the risk to reward ratio into the unsustainable. So I'd say, our current world (even 100-500 years into the future), would not be able to produce one of these projectiles, without neglecting self sustenance. Not to speak of a whole arsenal. But then, future technology, and more importantly, economical advances might remove this problem.

Assumption that other races are dangerous to own survival:

If the only thing that can reach aliens are one of the following three, then destruction of alien planets becomes unnecessary:
1. Radio transmissions at light speed
2. Almost light speed projectiles
3. Habitated space ships or robotic probes at slow speeds
Warp drives and faster then light travel notwithstanding, moving a live sustaining vessel for light years is costly beyond imagination. Sending a survivable amount of colonists to a planet is even more bonkers. Therefore destroying live on another planet would be useless to begin with, as we'd never have a need for another planet that far away. Ignoring that, bombing and then colonising such a far away planet would simply replace one adversary with another one, because control or unified acting as a single entity is simply impossible when all communication takes more then 20 years for a single question/answer (and finding a habitable planet within 10 light years is optimistic).

Radio silence:

We as a planet are not currently sending radio waves to aliens. This is due to several factors. Our radio transmissions are weak, and even tho they might reach out some, they do diminish in strength exponentially with distance. This is an effect of increasingly much space that the energy has to 'cover' in a 3-D sphere. It's like spreading butter on a bread too thin. Secondly, our radio transmissions are weak, compared to what the sun is producing. It's like using a walky-talky next to a military grade radio tower, on the same frequency. And thirdly, we don't actively try to send out centred, clear transmissions to a single space, but send radio waves that are ideal for small distances. Meanwhile, we are listening on single, high probability spaces ourselves. Why? Because sending to another planet on purpose takes a ton of energy, while listening doesn't cost almost anything at all.

In essence the proposed "dilemma" is so highly abstracted from reality, that it becomes false. Unless we discover an important use for distant planets that are habitable, this is useless at best, but actually misleading and fearmongering/uncertainty/destructive (FUD) at it's worst.

On January 09 2012 05:30 Ender985 wrote:
Probably hitting the Sun with an RKV would be much easier than hitting Earth, and the effects of doing so would be probably life-ending not only for our planet, but for all possible colonies established through the star system.

On January 06 2012 07:01 sviatoslavrichter wrote:
Why is the universe so full of stars but so silent?

EDIT #6: People keep trying to use traditional methods of game theory and int'l relations theory to think about this. The core problem here is that all these theories rest upon the assumptions of instantaneous communication and easy identification of who is responsible for the killing. Unfortunately, across interstellar distances, both are untrue, and especially compared with how fast weapon systems themselves can move, and also especially compared with how technologically hard it is to see who is doing the killing versus breaking the agreement yourself. This is why I've avoided using math in describing this post, as any game theoretic analysis I ran here would immediately be invalid because every freaking game theory principle out there rests on people being able to talk to one another..

On January 07 2012 02:36 Greentellon wrote:
Any species capable of inter-galaxy space travel will be so advanced that all they see when they meet us is ants or bacteria on a rock.

How do you communicate with an ant or a bacteria?

Let's say there is a 1 billion year old species out there that is dominant in our galaxy. Just think how much technological advancements we have done in the last 100 years. Things we have done include first steps of space travel, a planetary wide communication network where any person can soon contact any person withing few seconds, scientists are already working on making things invisible, sound-based weaponry already exists, nuclear weapons, we cure diseases with genetic modification (or try to), cloning attempts have been done with variying success..

We did that in last 100 years or so. Now think what a species can do in 1 billion years. So yeah, if that species is dominant then we are just ants on a rock compared to them.

Why is the universe so silent? Because we can't comprehend it well enough to be part of it.

The impactor that is believed to have created the Chicxulub crater delivered 4x10^23 J. Going at your recommended 0.5 c, and using the relativistic equation for kinetic energy you would need an object that has a mass of 2.9x10^7 kg. If you were to use iron, which has a density of 7,874 kg/m^3, you would need a sphere that is 380 meters in diameter. But the real problem is that iron is currently going at $0.22/lb. If you figure a 10% price break for bulk it would cost 1.4 billion dollars. And since that impact didn’t actually destroy all life on Earth, if we are aiming at an Earth sized planet we would need even more iron. So as soon as you amass, let’s say, 1.7 billion dollars I will help you research an accelerating laser to use for preemptive measures against a potentially hostile planet.

On January 11 2012 14:02 ghost_403 wrote:
So I was talking to my coworker, who has a PhD in some ridiculous field like material science or something, about the feasibility of a RKV. This is what he had to say:



tl;dr - I'm starting a collection for my research.