Aliens

[William Adams]

Read it somewhere, can't recall where. It ought to be covered in writing along the lines of: https://plato.stanford.edu/entries/knowledge-analysis/

EDIT: What number of facts do you believe would be necessary to understand an encyclopedia article using no other references? Please note that the article did mention that many of these were logical conclusions such as a child must be younger than a parent.

As an example of how difficult encoding information for A.I., a recent game tried to use A.I. agents for all the characters in the game --- when they first started one up, the in-game avatar simply stayed in place and looked at itself --- when they debugged the code they determined that it had determined it was in need of food, had identified its own body as the nearest foodsource and was trying to figure out how to eat itself.

Consider the recent instance of teaching a computer to play Go --- they simply had it play a copy of itself untold millions of times --- it worked, and created a program which could beat every other program in existence, but the game play style was unusual, and that's not a technique which can be used for other problems.

[Carlos Alvarez]

It's not just "learn like humans." If we want computers to be human, we have to teach them to do things that make no sense, to make mistakes, to be unduly influenced by things that aren't real, etc etc. Actual human or even animal behavior isn't just about acquiring knowledge or following a set of possible paths. Consider that no two humans will do the same thing when confronted with an event or other input.

[Bert Kemp]

100 % true Dave if another life form has visited earth they surly know theres no intelligent life here

I would say the probability is high given the number of galaxies, let alone the number of stars. Now as for life forms visiting earth, I don't doubt it has happened. I do suspect however that they have left us alone after determining that there was no intelligent life here.

[Pat Barry]

If an alien expedition were to arrive here their only interest would be obtaining resources to ensure their own future. It is unlikely humans would be anything more meaningful to them than slave labor to extract those resources. Most likely humans would be a nuisance to them and would need to be eliminated. The question is, what resources would they want?

[Frederick Skelly]

If an alien expedition were to arrive here their only interest would be obtaining resources to ensure their own future. It is unlikely humans would be anything more meaningful to them than slave labor to extract those resources. Most likely humans would be a nuisance to them and would need to be eliminated. The question is, what resources would they want?

Blood. Immortal alien vampires!

(Sorry Pat. Your point was fair. I just couldnt resist being silly.)

[Carlos Alvarez]

If an alien expedition were to arrive here their only interest would be obtaining resources to ensure their own future. It is unlikely humans would be anything more meaningful to them than slave labor to extract those resources. Most likely humans would be a nuisance to them and would need to be eliminated. The question is, what resources would they want?

The spice. He controls the universe.

[Warren Wilson]

I am surprised no one has yet mentioned the Drake Equation, a "probabilistic argument" that estimates the number of extraterrestrial civilizations in the Milky Way with which we could communicate.

I am pasting the seven variables from the Wikipedia article -- the notion has long made sense to me, especially after seeing it featured on The Big Bang Theory (so it HAS to be correct).

1. R_∗, the average rate of star formations, in our galaxy,
2. f_p, the fraction of formed stars that have planets,
3. n_e for stars that have planets, the average number of planets that can potentially support life,
4. f_l, the fraction of those planets that actually develop life,
5. f_i, the fraction of planets bearing life on which intelligent, civilized life, has developed,
6. f_c, the fraction of these civilizations that have developed communications, i.e., technologies that release detectable signs into space, and
7. L, the length of time over which such civilizations release detectable signals,

So the final expression of N (the number of such civilizations) is the product of those variables, or

[William Adams]

Yes, but you then need to further adjust down for the distance / speed at which radio waves travel --- there's a great image showing how far ours have gotten --- rather sobering.

Unless there's a way to cheat and go FTL, we're looking at Poul Andersen's _The Boat of a Million Years_, Vernor Vinge's _Longshot_, Ben Bova's _Exiles Trilogy_ and the like being the only options for interstellar travel --- unless we can get some sort of self-perpetuating asteroid mining going, a generation ship is looking to be a planet-wide commitment (consider that no one has gotten to Mars in person yet) and asteroid mining is problematic due to the delta vee involved. We can't even work out how to get the energy and apply it to near miss asteroids.

[Carlos Alvarez]

Yes, but you then need to further adjust down for the distance / speed at which radio waves travel --- there's a great image showing how far ours have gotten --- rather sobering.

Only if you believe that's the only way to send intelligent signals. Quantum entanglement seems like a real possibility so far. And while gravitation waves are still limited in speed in the way WE see them, there's so much we don't know about gravity (and that can indeed carry a logical signal). Then there are the dimensions we can measure and not see, such as dark matter which is passing through you right now. What is it? Can we communicate with it, using it or directly at it? Is it another superimposed universe? Heck, are "ghost" sightings just a special entanglement with a dark matter universe when it somehow crosses ours in a way that renders a short connection?

Imagine a 2D ant on a sphere. It can travel that sphere indefinitely and think that its universe is infinite. But we 3D observers can see its obvious limited space. The most logical "fourth dimension" is time, which we can only perceive linearly and in a single point. Remember that time and space are the same thing; points in dimensions we can perceive. What about all of the other likely dimensions? You put a person on a tightrope and he can only walk in two dimensions, limited by his scale. Yet put an ant on a tightrope and it can travel in three dimensions. There are good theories about how scale plays into travel in various space/time continuums.

Dogs can hear sounds well above 30kHZ, so they already have a different perception of the world. Moths and bats can hear to 100k, so they have yet another view. Some animals like the Mantis shrimp can see colors we simply cannot, even inside our own limited visible spectrum. It has 12 color receptors to our 3, but at the same time appears almost color blind when we as humans test it. Is that because we can't possibly understand what it actually sees? Other animals can perceive many energy types that we cannot. Yet we think we're the hot sh!t in the universe.

Aliens...I think today that's just a catch-all term for "things we don't know exist and haven't talked to yet." Meaning that they could be dimensional travelers (purposely or accidentally), or really from our dimension and another planet, or who knows? Everything we know about what "can be" is limited by our extremely limited view of the universe plus our fears and prejudices.

[Carlos Alvarez]

IMG_0089.png

This sums up the perception problem.

[William Adams]

Controlling gravity and so forth are even further out than FTL.

The problem the with sentient ant thing is that they should have been sprayed w/ pesticides and be reacting to that as chemical warfare.

A small scale sentience would all-too-readily begin to take advantage of resources created by humanity and become a pest, see _Mrs. Frisby and the Rats of N.I.M.H._ for a discussion of this.

BTW, there's a great story (unfortunately that it is is a spoiler) about Mantis Shrimp in Fred Saberhagen's _Berserker_ canon --- highly recommended.