Extraterrestrial Minds.

              The universe is not only stranger than we imagine, it is stranger than we can imagine.
              Haldane. Possible Worlds and Other Papers (1927), p. 286 [1].

                                          1. ExtraterrestrialMinds
                                          2. Drake Equation
                                          3. Search For Other Worlds - The Kepler Mission.
                                          4. Alien Civilizations.
                                          5. SETI and CETI.
                                                The Omega Number.
                                          6. Von Neumann Robots
                                          7. Galactic Net
                                          8. Rise Of The Machines.
                                          9. Communication with Enhanced Super Minds.
                                          10. Boltzmann Brains.
                                          11. Matrioshka Minds.
                                          12. NeutronStar Computer.
                                          13. Baby Universe.
                                          14. Nick Bostroems Simulation Argument.
                                          15. Quantum Computers.
                                          16. Quantum Gravity Computers.
                                          17. Conscioussness in 4+ Dimensional SpaceTimes?

1. Extraterrestrial Minds.

We don't know what is out there.

But, according to Ellie Arroway (i.e. Carl Sagan): I'll tell you one thing about the universe, though. The universe is a pretty big place. It's bigger than anything anyone has ever dreamed of before. So if it's just us... seems like an awful waste of space. Right? [2].

So, what could be out there?

Well, this is what this page is all about! But the list here is of course no way near complete. How could it be?
But it is an attempt to list some of the different kinds of intelligences that might lurk out there in deep space and beyond.

Brains in the middle world - what can we know?

According to biologist Richard Dawkins we humans live in the ''middle world''.
We are not small like atoms, and we are not big like galaxies. We are in the ''middle''. And obviously, our brains were designed to live in ''middle world'', and to understand ''middle world''. Our brains were not designed to understand the world of the very small or of the very large.
In the middle world newtonian physics rules. Not weird quantum physics (small world), or general relativity (the world of the large).

This said, can we then hope to ever understand anything about life in small world or in large world?

Concerning minds in the (small) quantum world, we know that things must be very strange there.
Indeed, in small world we have (Vedral, june 2011):
''Space and time are two of the most fundamental classical concepts, but according to quantum mechanics they are secondary.
The entanglements are primary.
... They interconnect quantum systems without reference to space and time.''

Weird, certainly. But Vedral thinks that ''small world'' physics might also apply to us. For some reason we just see don't see it that way. Fuzzy, certainly. But maybe it will be understandable one day...?
(Still, replacing the simple ''one solution'' pattern of our middle world memories with the ''many solutions'' pattern of the small quantum world will probably take a little getting used to though).

Life in large world has been described by several authors:

In Greg Egans ''Incandescence'' we get a very thorough tour of what it would be like to live under other gratitational circumstances. But, certainly, without the explanations at gregegan.net, most people struggle to make heads or tails of the chapters concerning general relativity?

In Fred Hoyles ''The Black Cloud'' an immense cloud of gas is heading for the solar system. A cadre of astronomers and other scientists is then drawn together in Nortonstowe, England, to study the cloud and report to the British government about it. The behaviour of the cloud proves to be impossible to predict scientifically, the team at Nortonstowe eventually come to the conclusion that it might be a life-form with a degree of intelligence. In an act of desperation, the scientists try to communicate with the cloud, and to their surprise succeed in doing so. The cloud is revealed to be a superorganism, many times more intelligent than humans. The cloud is surprised to find intelligent life-forms on a solid planet.

Sure, some lifeforms might be to big for us to phantom. And indeed, when light speeds are relavant, sequences becomes observer dependent - and the mind boogles. Still, authors like Fred Hoyle and Greg Egan lets us believe that we don't need to give up completely. That we might actually understand something about what is going on in large world?

So, maybe there is hope? Maybe our middle world brains might actually understand a little bit about what brains in other worlds might be all about? We just need to find these brains!

Zoo hypothesis.

And hope that we don't live in some kind of cosmic zoo, where we are really the only intelligent beings around.
In ''Phase Space'', acclaimed SF author, Stephen Baxter writes about the Zoo Hypothesis:

                  According to ''The Planetarium Hypothesis: A Resolution of the
              Fermi Paradox'' (Journal of the British Interplanetary Society,
              vol 54 May/June 2001) we might live inside a ''bubble'':

                  How could we really prove that the stars and galaxies, we see
              on the night sky, aren't simulated on a great shell that
              surrounds the entire solar system? A shell that simulates not only
              photons, but also such exotica as cosmis rays and neutrinos etc. ???
                  And beyond the shell lies the REAL universe. A universe that
              we know absolutely nothing of....!
                  According to this, ''planetarium hypothesis'', the ''controllers'' might
              have created our little ''zoo'' for the sanity of the human mind!?
                  Or they might be fastforwarding humanity inside some exclusion zone,
              to see how it turns out? Perhaps the universe, we know,
              is some elaborate illusion that protects us from a more fearful reality?

              See full text [3] for more...

Let the search begin.

So, if we don't live in a zoo and with our middle world bias mentioned (and well, many other reservations could probably have been mentioned here), we can proceed with caution. Optimistic that we might actually find something out there, and that we could actually understand at least some of the things out there.

2. The Drake Equation.

The Drake equation is an equation used to estimate the number of detectable extraterrestrial civilizations in the Milky Way galaxy.

N = the number of civilizations in our galaxy with which communication might be possible;
and
R = the average rate of star formation per year in our galaxy.
fp = the fraction of those stars that have planets.
ne = the average number of planets that can potentially support life per star that has planets.
fl= the fraction of the above that actually go on to develop life at some point.
fi = the fraction of the above that actually go on to develop intelligent life.
fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space.
L = the length of time for which such civilizations release detectable signals into space.

Drake and his colleagues gave the following values back in 1961 :
R = 10 stars formed per year, on the average over the life of the galaxy.
fp = half of all stars formed will have planets.
ne = each star with planets will have 2 planets capable of developing life.
fl= 100% of these planets will develop life.
fi = 1% of which will be intelligent life.
fc = 1% of which will be able to communicate.
L = each civilisation will last 10,000 years.

Drake's values give N = 10 x 0.5 x 2 x 1 x 0.01 x 0.01 x 10,000 = 10.

But in some slightly more optimistic numbers, and you get 20.000 civilisations. With the nearest one only 350 light years away.... With all of this radio silence they must be pretty scared out there?
I.e. an alien civilization might feel it is too dangerous to communicate, either for us or for them. After all, when very different civilizations have met on Earth, the results have often been disastrous for one side or the other, and the same may well apply to interstellar contact. Even contact at a safe distance could lead to infection by computer code. Yes. even ideas themselves by unsafe.

Or maybe we are already in contact. As Leo Szilard once suggested: ''The extraterrestrials are already among us, they call themselves hungarians''.

3. Search For Other Worlds - The Kepler Mission.

Kepler [4], [5], [6] is a NASA spacecraft equipped with a space observatory designed to discover Earth-like planets orbiting other stars.
On 2 February 2011, the Kepler team announced the results from the data of May to September 2009. The Kepler results included 68 planetary candidates of Earth-like size and 54 planetary candidates in the habitable zone of their star. The team estimated that 5.4% of stars host Earth-size planet candidates and 17% of all stars have multiple planets.

So:
When will we observe the first Earth-like planet (Earth twin) outside our own solar system?

Must be rather close now....? See discussion here!

Indeed, Kepler could make you believe that questions like:
1. When will we discover the first certain signs of life outside Earth?
2. When will we have the first signal from exo life?
3. When will we have our first signal from intelligent exo life?

might be answered within our lifetime!
Indeed, those alien civilizations might be closer than we think!

4. Alien Civilizations.

So, what are the alien civilizations going to be like?
According to Dr.Michio Kaku there are (at least) 3 types of alien civilisations:

''Type 1'' Civilisations.
Anything planetary they control. The weather. Earthquakes.

''Type 2'' Civilisations.
They use the power of their sun itself to energize their civilization.

''Type 3'' Civilisations.
They go galactic. They harness the power of many stars.

So, what are we on this scale? We are ''type 0''. We get our energy from dead plants. We will be ''type 1'' within the next 100 years. Then, we will have a ''type 1'' language, english, and a ''type 1'' culture, Hollywood etc.

What is ''type 3'' civilisations capable of? Well, for starters, they might be able to create babyuniverses in their local labs. Maybe, put in some slightly different physical parameters in these ''baby universes''? I.e. they might be able to create ''designer baby universes''. Probably, complete with Big Bang radiation, where you can find messages from the creators? And, commercials from your galactic Walmart?

Really, anything is possible (For more, see here). Indeed, it is all going to be magic for us, according to Clarkes third law:

Arthur C. Clarkes 3 laws:
1. "When a scientist states that something is possible,
he is almost certainly right.
When he states that something is impossible,
he is very probably wrong".

2. "The only way of discovering the limits of the possible
is to venture into the impossible".

3. "Any sufficient advanced technology is indisguishable
from Magic".

5. SETI and CETI.

The search for extraterrestrial intelligence (SETI) has been going on for some time now. Indeed, people have been trying to communicate (CETI) with the alien civilisations for than 100 years.
E.g. Inventor Nikola Tesla mentioned many times during his career, that he thought his inventions such as his Tesla coil, used in the role of a "resonant receiver", could communicate with other planets and even observed repetitive signals of what he believed were Extraterrestrial radio communications coming from Venus or Mars in 1899. However, these "signals" turned out to be terrestrial radiation [7].

Well, no luck sofar though.
But, if we suceeded what would we and the aliens communicate about?

In Communication with Alien Intelligences Marvin Minsky speculates about the things we might want to talk with aliens about. According to Minsky, ''the ability to solve hard problems, like the kinds a species must solve to build such things as spaceships and long-distance communication systems.'' - is key. Humans solve such problems fast (speed is really a key ingredient in intelligence!?) and we expect the aliens to have similiar capabilities.
Then, what makes us able to do such hard things fast? The following ingredients seem so essential that we can expect intelligent aliens to use them, too:

SUBGOALS ----------- to break hard problems into simpler ones.
SUB-OBJECTS ------ to make descriptions based on parts and relations.
CAUSE-SYMBOLS--- to explain and understand how things change.
MEMORIES ---------- to accumulate experience about similar problems.
ECONOMICS -------- to efficiently allocate scarce resources.
PLANNING ----------- to organize work, before filling in details.
SELF-AWARENESS-- to provide for the problem-solver's own welfare.

I.e. First up in our communication with the aliens: Work out, common notation, for solving problems generally. Then move on to specific problems and their solution.

For more than a decade after SETI's launch, SETI's organizers invited AI pioneers like McCarthy, Minsky and Michael Arbib to key SETI conferences. SETI scientists considered the AI researchers the reigning experts on the subject of intelligence, and actively sought their opinions about the nature of intelligence and the likelihood that it would evolve elsewhere.

One of the best candidates for an exterrestrial SETI signal, sofar, was the wow signal in 1977.
It lasted for the full 72-second duration that Big Ear observed it, but has not been detected again. Hard to see how the Wow signal could contain any manuals for solving hard problems though?

Omega Number.

What we really want from the clever aliens is of course the Omega Signal. A key to infinite-like knowledge.

Omega = halting probability.

I.e. according to Alan Turing you can't decide whether a (computer) program will halt. There is no mechanical procedure for doing that. As most problems can be recast as halting problems, this is pretty universal. The real number Omega is then the probability that a program generated by tossing a coin halts. The answer to whether statements (coded as Turing questions) are either true or false.

Quoting Calude:

''Omega embodies an enormous amount of wisdom in
a very small space... its first thousands digits,
which could be written on a small piece of paper,
contain the answer to more mathematical questions,
than could be written down in the entire universe.''

Receiving the first, say, couple of thousands digits of the Omega number would allow civilization on Earth to fast forward thousands of years in an instant [8], [9].

6. Von Neumann Robots.

Instead of receiving signals from deep space we might eventually meet aliens in the form of Von Neumann Robots.
Self-replicating machines that is theoretically capable of autonomously manufacturing a copy of itself using raw materials taken from its environment: Machines with the capacity to gather energy and raw materials, process the raw materials into finished components, and then assemble them into a copy of itself.

In Arthur C. Clarkes 2001 humans meet alien Von Neumann robots (in the shape of Monoliths)....
Indeed, in theory, a self-replicating spacecraft could be sent to a neighbouring star-system, where it would seek out raw materials (extracted from asteroids, moons etc.) to create replicas of itself. These replicas would then be sent out to other star systems etc.

For some, the fact that we are not walking around in alien Von Neumann robots here on Earth, is proof that we are really, truly alone in the Galaxy.
I.e. Given even a moderate rate of replication and the history of the galaxy, such probes should already be common throughout space and thus, we should already have encountered them. Because we have not, this shows that extraterrestrial intelligences do not exist.....

7. Timothy Ferris - Hook up to the Galactic net.

Without direct signals from the aliens homeplanet, and without any Von Neumann Robots here in our own solar system, we must seek out some other way to get in touch with the Extraterrestrial Minds....
Timothy Ferris suggest that we try to hook up to the Interstellar Internet..... An alien version of our own Interplanetary_Internet. Communication-wise, hooking up to an interstellar internet might not be all that different from other CETI communications. But if the interstellar internet has a node here in our own solar system, communication might be a lot faster.

8. Rise of the machines.

Maybe it will not be all that easy to talk to the aliens? Maybe (surely), we will need intelligent machines to act as translators. Maybe, the aliens (we want to talk to) are themselves machines? Maybe the only alien intelligences, we will ever really come in close contact with, will be our own machines?

Actually, a civilizations own machines might be the solution to the Fermi paradox (the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for, or contact with, such civilizations).

When a civilization proceeds towards a Kurzweilian future (See my posts [10] and [11]), eventually, artifical super-intelligence, AI++, explodes onto the scene.
As a civilisation merges with these artificial intelligences, the civilization might end up being totally self-absorbed (not communicating with anyone).
Not unlike Pierre Teilhard de Chardins [12] Omega Point [13], in which mankind will have reached its highest point of complexification and thus its highest point of consciousness. At this point, according to Teilhard de Chardin, consciousness will rupture through time and space.
In The Phenomenon of Man Teilhard de Chardin states that the Omega Point will be:
a) Personal - i.e. an intellectual being and not an abstract idea and b) Transcendent.
- Go figure! :-)
Frank Tiplers Omega Point ([14], [15]) follows suit. Here (at Tiplers Omega Point), the computational capacity of the universe (in terms of both its processor speed and memory storage) is also capable of increasing unlimitedly.

Hugo De Garis thinks humanity might have opted out long before this though [16].

9. Communication with Enhanced Super Minds.

Well, what will really happen to Homo Sapiens, as artifical super-intelligence, AI++, explodes onto the scene?
What will happen to our small dreams about one day meaning fellow biological creatures. Creatures similar to us - with limited intelligence, limited lifespans etc. Someone who really understand what it is to be like us...

Surely, the superpowers of the future will not understand such desires, but will have their own agenda:

Let an ultraintelligent machine be defined as a machine that can far surpass all the intellectual activities of any man however clever. Since the design of machines is one of these intellectual activities, an ultraintelligent machine could design even better machines; there would then unquestionably be an ''intelligence explosion'', and the intelligence of man would be left far behind. Thus the first ultraintelligent machine is the last invention that man need ever make.
I.J. Good, 1965

Indeed, according to David Chalmers and others, AI++ is coming.

Where:
AI: Intelligence of human level or greater.
AI+: Intelligence of greater than human level.
AI++: Intelligence of far greater than human level.

Because:
(1) There will be AI+ (Because there will be AI).
(2) If there is AI+, there will (soon afterwards) be AI++.
It follows:
(3) There will be AI++.

And we better simulate the whole thing first. Just in case.
I.e. there might be both benign and non-benign scenarios coming out of this.

If a post-singularity simulated world is not benign, we can try again. If it is benign, we can attempt integration (with it) in a controlled way.

But:
Q: How can we encourage AI++ to think about us, and help us meet the aliens, we so eagerly want to share our life experiences with?
Well, it has been suggested that we should:
A: Post articles on the internet and give talks about the singularity - Suggesting to future (enhanced minds), that they should keep us (or reconstruct us), to preserve their own deep past. Maybe, they will be curious, and actually do as we wish.

10. Boltzmann Brains.

Boltzmann Brains are hypothetical brains:

Resulting from thermal or vacuum fluctuations - Boltzmann Brains comes from nothing... In stark contrast to a human brain, which is the result of an evolution stretching back through most of the history of planet Earth. What are the chances then that an everyday object - a rock, a chair, you name it - could suddenly appear out of thin air? Not zero, surprisingly. In fact, given enough space and time, it is conceivable that a conscious being could arise, even if only for a microsecond.

So, out there in the infinite universe we have:
...Interstellar clouds of hydrogen, which happens to instantiate a particular Turing machine (Boltzmann Brain), but only for a tiny instant before it goes into another arrangement. Thus, not only will smaller systems be more frequent, but briefer systems will be more frequent; it is very unlikely that a large and long-lasting entity like a human brain will appear by chance, but rather more likely that very brief human brain-equivalent snapshots will arise, widely separated in time and space.....

Thats pretty weird. Still, You might wonder what's wrong with a few brains - or even a preponderance of them - floating around in space. For one thing, as observers these brains would see a freaky chaotic universe, unlike our own, which seems to persist in its promise and disappointment.

But here comes Boltzmann:
Suppose the universe had two choices: One is to allow the great big exception to the second law known as the history of human evolution and civilization. The second is to allow the comparatively minor exception which would have you spontaneously come into existence, for a few seconds, with all the memories, perceptions, and expectations you are experiencing right now. Case number two is the smaller breach of entropy. So we should believe that that's the truth:
You think you are part of a great big exception to entropy, but you're not. You're something like a one-second-old brain in a vat. A Boltzmann Brain .....

Well, not really, on Earth we are part of a big system that produces brains. A system with active mechanisms which lead to processes of development, with reasonable probability of producing a species such as ourselves....phew...

The take home point is, that there are some pretty weird brains out there!

11. Matrioshka Minds.

The term Matrioshka mind was invented by Robert Bradbury.
Such a structure would be composed of two or more Dyson spheres built around a star.
Many possible uses of such an immense computational resource has been suggested. One idea suggested by Charles Stross, in his novel Accelerando, would be to use it to run perfect simulations or uploads of human minds into virtual reality spaces supported by the Matrioshka mind.

So, the aliens we want to communicate with might be long dead, but simulations of them might be floating around in Matrioshka minds in deep space. Well, maybe we could one day be allowed to upload one day on Earth to such minds?

12. Neutron Star Computer.

In the article Superdense Computers Hans Moravec wrote:
Someday neutron stars may be the preferred location for monster super computers since they are common and large [17]. According to Hans Moravec, life there could exist as a pattern of bounded neutrons. With a breakneck speed of metabolism. Where organisms live and die within 10e-15 seconds. Entire civilisations might be formed within a fraction of a second.

In Mind Children from 1988 we read:
''The benefits of miniturization need not stop at the atomic scale!
While ultradense matter that is stable on Earth is just a speculation, vast quantitites of similiar stuff is known to exist in the tremendous gravity fields of collapsed white dwarfs and neutron stars. Someday, our progeny may exploit these bodies to build machines with a million million million million million (10^30) times the power of a human mind.''

(I imagine it made out of a superdense neutron star) that can model the whole surface of the Earth on a atomic scale and can run forward and backward and produce different plausible outcomes by making differenct random choices at key points in the calculation. Because of the great detail, the simulation models living things, including humans, in their full complexity. According to the pattern-identity position, such simulated people would be as real as you or me, though imprisoned in the simulator.

And Moravec had the following posted on Usenet back in 1992, where it is suggested that the moment we are now experiencing is a complete fabrication, made on some (neutron star) super computer..........:

> Pigs in Cyberspace.

> Hans Moravec
> Robotics Institute
> Carnegie Mellon University
> Pittsburgh, PA 15213
> May 1992

> ''If these minds spend only an infinitesimal fraction of
> their energy contemplating the human past, their sheer
> power should ensure that eventually our entire history
> is replayed many times in many places, and in many
> variations. The very moment we are now experiencing
> may actually be (almost certainly is) such a distributed
> mental event, and most likely is a complete fabrication
> that never happened physically. Alas, there is no way
> to sort it out from our perspective: we can only wallow
> in the scenery.''
> Hans Moravec
> Date: Sun, 4 Oct 1992 08:40:15 GMT
> Message-ID: <2siae1$6q0@nbc.ksu.ksu.edu>
> Message-ID: [18].

I couldn't see why we should stop with computers in neutrons stars. So, shortly thereafter, I was (probably) the first to suggest the following addendum (in various forums back then):

''....Advanced civilisations might create such neutron stars in order to use them as computers. Some 10e30 more powerful than the human brain....
My own addendum to this is that it would be neat to press things even further and install computers in the fabric of spacetime itself. Smash the neutron star a bit further and create a black hole, which explodes into a new universe (big bang) with the new order (computer) installed in its very fabric of space and time.''

Most of these discussions are now (unfortunately) lost in cyberspace, but a few traces can be found here: [19], [20].
Back then this was pristine new territoty. And it was only much later that quantum computing, ''Big Bang lab experiments'' etc. made such thinking ''mainstream'' (See below).

13. Baby Universe.

Our visible universe might be a 3-brane floating in higher dimensions. Where branes float about in the higher dimensions of space, just as a two dimensional membrane, sheet, can float about in three dimensions.

According to Lee Smolin: ''The formation of a black hole creates ''baby universe'', the final singularity of the black hole tunnelling right on through to the initial ''big bang'' singularity of the new universe thanks to quantum effects.''
I.e. the matter in a black hole seeds a baby universe and the information goes *there*.
Certain parameters of the baby universe are close to, but not complete the same, those of the parent universe...
And here the whole thing turn wonderfully Darwinian:
Those universes whose parameters are such that many black holes are formed will have many progeny, so the constants of physics can be expected to be ''tuned'' for the formation of many black holes!

Now, a universe might be created with a) laws of physics that makes certain beings likely (!?), or b) a universe might be artificially seeded (- Not to be explored further in this chapter - See discussion above in the Neutron Star chapter about seeds in the fabric of spacetime) with entanglements that makes it compute (or be aware of?) a certain problem put in by the designers.

In John Gribbins In search of the multiverse the aliens seems rather hellbent on playing around with the laws of physics in these baby universe. Producing the ''universe-stories'' they would like to see explored as these baby-universes unfold.

It is still basicly a Smolin setup though: A black hole in one spacetime collapses and tunnels into another spacetime, the physical properties of the new spacetime, such as the strength of gravity and the values of the other constants of nature, are very nearly, but not quite, the same as in the parent universe. Just like the way in which small mutations in DNA, mean that the genome of a baby animal or plant is very nearly, but not quite, the same as the genome of the parents. The idea of natural selection of universes removes life, including human life, from centre stage im the story. And makes the proliferation of black holes the important thing?

But why have natural selection of holes, if you can have artificial selection of holes? According to Ted Harrison there are many ways a universe could be created in an alien laboratory. See, Was the Universe Created by Angels? [21].

Level 1. Manufacture black holes without any attempt to influence how the laws of physics in the new universe operate.
Level 2. Nudge the properties of the baby universes in a certain direction. E.g. make gravity a little bit stronger...Test that.
Level 3. The advanced civilisations set precisely the parameters of physics , thereby designing the baby universes in detail.

According to Ted Harrison: The superior beings who created our universe inhabited a universe not greatly unlike our own. They were not only intelligent, but intelligible, and were perhaps similiar to our distant descendants, who might also create (baby) universes.

I.e. the universe is comprehensible to the human mind, because it was designed, at least to some extent, by intelligent beings with minds similiar to our own. Fred Hoyle put it slightly differently: The universe is a put-up job ....

And:
The universe was created in the image, more or less, of the universe of the Designers.

14. Nick Bostroems Simulation Argument.

Will future civilisations have enough computing power and programming skills to be able to create ''ancestor simulations''? - that is the question Nick Bostrom asks us to consider. I.e. will someone be doing detailed simulations of the simulators' predecessors - detailed enough for the simulated minds to be conscious and have the same kind of experiences we have? Perhaps not now, or in 50 years, but within say 10 million years.

If we extrapolate the expected technological advances and think through the logical conclusions we arrive at the the simulation argument:

1. Almost all civilisations at our level of development become extinct before becoming technologically mature.

2. The fraction of technologically mature civilisations that are interested in creating ancestor simulations is almost zero.

3. You are almost certainly living in a computer simulation.

If the simulation argument is correct, at least one of these three propostitions is true (it does not tell us which).
See the Simulation argument.

Great! We are living in a simulation run by crazy aliens bored with making baby universes.

But how could we know?
Sure, the simulators could make a ''window'' pop up in mid air in front of you with the text ''YOU ARE LIVING IN A COMPUTER SIMULATION'' - think Greg Egan here - But otherwise, it would probably be really difficult to tell the difference between ''reality'' and a simulation.

According to John Barrow , if we are living inside a simulation, there ought to be clues in the form of ''glitches'' in the laws of physics: The simulation would fall victim of the incompetence of their creators. Errors would accumulate. Prediction would break down. The world would become irrational.

Have you noticed any of this recently?

And btw. What are you really supposed to do inside a simulation to make the aliens running the simulation happy?
Prove the Riemann_hypothesis?
In Arthur C. Clarkes The Nine Billion Names of God, Tibetan munks believe the Universe was created in order to note all the names of God and once this naming is completed, God will bring the Universe to an end.
They rent a computer capable of printing all the possible permutations, and they hire two Westerners to install and program the machine. Later, under a clear starlit night sky, the westerners estimate that it must be just about the time that the monks are pasting the final printed names into their holy books. They notice that ''overhead, without any fuss, the stars were going out.''

Yes. perhaps our universe is really ''Stephen Wolfram computational'', rather than being a ''physical universe''?
But why bother simulating the whole thing? Rather than simulating the complete workings of every quasar and star, why not simulate, say, the planet Earth in detail, with fake information coming into telescopes and other detectors?

It is a big place out there. Perhaps even infinite, with all of us having dobbeltgaengers running around out there. So, the aliens must really like simulations, if they want to simulate it all....

15. Quantum Computers.

According to Seth Lloyd, the universe is indistinguishable from a quantum computer [22]. Indeed, the universe supports quantum computation and can be efficiently simulated by a quantum computer. Put another way - when two physics systems can simulate each other efficiently - they are logically equivalent. No easy trick though - to simulate the entire universe - in order to it, a quantum computer would need exactly as many qubits as the universe. Talk about Jupitor sized computers.

Smaller simulations are also interesting though:
According to David Deutsch: Quantum Computers get their enormous computational power by farming out computing problems to other universes in order to achieve tractability for solutions that otherwise get bogged down by exponentially increasing demands for more time and other computational resources.

Indeed, in this multiverse quantum world, a person is a set of copies in nearby parallel worlds. ''I could have chosen otherwise'', is analysed as ''Other copies of me chose otherwise''. There are ''multiple identical copies'' of me in the multiverse. Which one am I? Deutsch answers, "I am, of course, all of them."

Some of these ''I''s are ignorant fools, not really consciouss about anything. Others are brilliant people making contact with aliens over the Big Bang afterglow radiation. Each of us has to decide, which one of them we want to be?

16. Quantum Gravity Computers.

Quantum gravity computers will be lots of fun.
I.e. Quantum gravity does away with cause and effect. In classical computing one thing follows after another.
''If'' is usually followed by ''then''. Even quantum computers has this notion of input followed by output. Quantum gravity computers will not be constrained by such considerations. Noone knows how space and time act on the scale of quantum gravity, but there will certainly be no such thing as a fixed sequence of processing steps [23].
It is probably around here that our middle world brains gets somewhat stretched....
We might not know where all the alien intelligences hang out... But surely we could ask a (quantum gravity) computer?

17. Conscioussness in 4+ Dimensional SpaceTimes?

Gamma Ray bursts (caused by colliding neutron stars or some other mechanism) is not something the human species wants to witness close-up.
Which btw. exlains the Fermi Paradox. Smart species don't want to be toast - so they left the Galaxy...... :-)

In Greg Egans ''Diaspora'' [24] things are going great for humanity in the late twenty-first century... Sure, there is a mass influx of blood and flesh humans into computers or networks of computers... All in all it is an ersatz ''Garden of Eden'' for humanity.

But then there is this nasty core blast thing.
Sure, wormholes to other galaxies might save us. But to use them, our minds might need major repair work to cope in a, say, 5 dimensional universe? Exploration will go on long after this though.... And only stop after an eon or two, when we will be ''complete''. Having played out every possibility within ourselves. Or so at least according to Greg Egan....

Yes, it is really, really weird out there....
As when approaching a singularity in space (say a black hole). Slight irregularities in distribution of matter in space(time) will become ever more magnified, and eventually chaotic. Warped spacetime will vary wildly depending on direction, and eventually shatter, splitting into droplets, "before" and "after" will loose all meaning, as will "distance" and "direction" [25] ....

And aliens might really live out there, even in the 11th dimension (Youtube Video) ?
We just need to find them .......

Posted on Usenet:
From: Simon Laub
Newsgroups: rec.arts.sf.written,rec.arts.sf.science,comp.society.futures
Followup: rec.arts.sf.science
Sent: Sunday, August 28, 2011 12:38 AM
Subject: Extraterrestrial Minds - What is out there?

-Simon

Simon Laub
www.simonlaub.net