[mojo]

The Fermi paradox or Fermi's paradox, named after Enrico Fermi, is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations, such as in the Drake equation, and the lack of evidence for such civilizations.[1] The basic points of the argument, made by physicists Enrico Fermi (1901–1954) and Michael H. Hart (born 1932), are:

    There are billions of stars in the galaxy that are similar to the Sun [2][3] including many billions of years older than Earth.[4][5]
    With high probability, some of these stars will have Earth-like planets,[6][7] and if the Earth is typical, some might develop intelligent life.
    Some of these civilizations might develop interstellar travel, a step the Earth is investigating now.
    Even at the slow pace of currently envisioned interstellar travel, the Milky Way galaxy could be completely traversed in about a million years.[8]


Source

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Fermi's basic question of 'Where are they', was made during lunch with several other scientists. The implications of the question were fairly obvious to those who heard them with out his needing to break down the meaning of the question. Every one understood he was talking about why the Earth doesn't have recorded proof, known to the public, of some other galactic civilization in existence. The basics were, why haven't we been visited and why don't we know about it.

The basics behind the statement are that if a civilization developed a star drive of some sort, even a generation ship and colonized a new planet, and if that planet as well as the host planet that launched the ship then created another when they had the capabilities, within a million years or so of geometric progression, the entire Milky Way galaxy should be populated. Given that at some point we should have had a knock on the door so to say.

Yet everything we've done, gives no clue that we are not alone as far as an intelligence goes. We've tried radio searches, we've tried sending a message through both a wandering interstellar space craft (which admittedly won't be seen by other intelligences even if they exists for thousands of years), we've tried beaming a signal at what we believe to be the most likely candidates for life, we've listened to the galactic bands, but nothing we've tried has given forth results that indicate anything other than we are alone. So where are they?

We can go wild in speculation of 'what ifs' but the real thing comes down to we only know one kind of life that is proven to exist; ours. If there are other kinds of life, such as silicon based, rather than carbon based, it is speculation, no more, no less, with no proof of any kind such can/does happen. This is why NASA and all the other space agencies look for life as we know it. It's the one proven way.

Sometimes I like to speculate on the why's of this. For instance I believe there is a window if such another civilization exists, where contact is possible. Outside that window, there is no chance to recognize an alien signal as being from an intelligence. The most obvious example of this is a technological progression. You can't send a radio signal to a caveman and expect an answer. The caveman is simply not equipped to receive much less answer.

In the same way an advanced civilization wouldn't be recognized either as intelligent communications. In the era of the late 1800's early 1900's we are communicating with ships by Marconi's morse code with the new technology of wireless communications. The stronger the broadcast signal, the further you could reach out to sea to contact a ship. Those made sure that we had started an ever expanding globe of radio signals leaving this planet. Then came radio, where voices could be heard and code was no longer necessary. This followed in fairly rapid progression with TV, where not only were voices heard but images as well. Each time signals were ever more powerful as well as on different bands of the spectrum. Each advance complicated the signal but still appearing to the watchful as from an intelligent source.

Then came satellite bounces from earth to satellite back to earth. Only now the signals are less strong and they are being redirected back inwards, not outwards. Those signals being directed towards the satellite are now narrow band and unless you just happen to be in the right place, with super sensitive equipment, you're not going to receive them, if you were our alien equivalent looking for signs of intelligence. But it doesn't stop here.

Along comes pay for view and the broadcast companies need some way to keep people who don't pay from watching. So encryption comes along to answer that and suddenly your signal no longer makes so much sense. This progression keeps happening. It gets faster and faster to the changes as time goes along. Next thing you have is encoded signals where two signals are buried in one transmission. Think of it as two different stations on the same broadcast. One polarized differently than the other. Now we are looking at quantum entanglement. The idea that if two electrons are entangled, that time is not a factor in telling the difference in states. It's the basis for the next instantaneous communications with distant objects and theoretically should work should we have a colony on a different planet that there would be no time lag at all in communications. While the technology is still in it's infancy today, that's our future. How would you intercept this so called signal to tell it was communications?

This is my point on a window where communications are possible to be detected of an alien race. You try outside that window and you get nothing. One side or the other is incapable of recognizing the signal as being from intelligence.

[MSL]

 Some comments of mine:

1. I know about it earlier and when I read it -- nothing surprised me. Everything is pretty logical and scientific, so I think for the educated people it's even sort of boring (but I don't mean 'useless').

2. Why only cavemen? I think more advanced, but strictly religious civilizations (Earth's Taliban like or Amish like) will also stay in one and the same level and they will be also unable to detect high-tech signals.

3. From all the animals on Earth currently only 1 (Homo Sapiens) is able to think of signals, aliens, etc. From all the planets in the Solar system, only in one (most probably) there is life. So, we may conclude that the existence of life is difficult and the existence of clever life is more difficult.

 I think someday it's possible people to invent some kind of very powerful new generation telescope (or whatever they will call it), which will give the opportunity to see clearly the planets in other Solar systems. Then it will be more obvious what are the chances of the extraterrestrial (exo-) life to exist.
 But I still think that the priorities on Earth right now should be: reducing the wars and the tensions between nations; discovering some cure for cancers and other terrible diseases. First things first.

[mojo]

The reason for using the caveman as an example is everyone gets it right away. You don't have to explain that another culture isn't equipped because of religion or historical limitations. They understand on the spot about the caveman without further explanations.

Yes, there is nothing in this that is really revealing, only some it never occurs to. Either from lack of interest in the topic or it has to be laid out in a logical sequence to be seen and grasped for it's essence.

The rarity of life, not intelligent life, just life seems to be a step that is jumped over when people go to speculating about there being alien life in the universe elsewhere. Usually the first objection to intelligent life and we being alone is numbers. That's been partially covered in another previous post.

The new generation telescope is already on the distant horizon. Not in being made but the how to do. On a smaller scale we already do astronomical observations in the same manner on Earth today. The key here is the size of the aperture. How much gathering ability you have to observe with. One telescope (be that radio, visual, infrared, etc.) is limited by the size of it's collector. To increase the size, several points on the earth in different locations, with the same types of observatories, hook up to computers to balance the varying differences in time, etc and come out with a collector the size of the Earth in essence.

To increase this size means going into space with them. Picture two, three, or four, at different places across the solar system, spaced in opposition. More than enough to spot an Earth sized planet in a system. The biggest problem at this point isn't being able to gather the observing data, it's the glare of the star in the system being observed, which tends to blank everything else out in a globe of visual light, magnetic field, and the output of the star in the varying frequencies used to observe. Software and hardware has helped a lot in this providing a black spot to take out the interference provided by the star in the system being observed.

[mojo]

Seems I left something out in my answer. I'd like to address the last part of your post. The reason why to push on this now and not later after the many problems we suffer from here on earth.

One reason is non-renewable resources. By definition, non-renewable means once they are gone, there is no more to be had. If we wait till we solve all the problems on Earth, we'll never be able to leave to do this. We'll run out of the ability to make the things needed to get us there. For another, we will never solve all the problems on Earth. Our past history tells us this, for we have never, ever, solved all the problems in any civilization that has ever existed on Earth. As soon as one problem is solved, there's another at the door.

Typically in history, mines here on Earth has at best gotten around 12% return on mining. That 12% being the material actually being gone after. All the rest has been the stuff you have to move out of the way to get to it or what can not be obtained by technology we don't have yet to economically do it.

In contrast, were we able to mine our asteroids and comets, the purity of the elements there runs in the 90% range. Meaning that very little smelting and other processes have to be used to get the material that here on earth is bound up in other combinations. This in addition to some materials are not available on earth without extensive extra processes.

But let's look at one other major unrealized benefit that almost no one takes unto account till it shows up. From NASA's drive to develop the technology needed to address various problems we have all benefited from. Spin offs happen that provide untold and unthought of benefits to everyone. Things that just make your life easier, more capable, or better. Some have not showed up yet with useful applications in your life but are still in the pipeline coming. Others are now part of everyday life. None of which would have existed without the space effort. There's no way to calculate these benefits and what they mean to us.

It's like comparing life before electricity to after in some of them. So altering that no one can envision life without it after having lived with it all their lives.

Freeze dried foods, space blankets, modern medical advances such as vascular bypass, memory foam, the aerodynamic suits for the Olympics, Tang, velcro, and teflon only to name just a few of the thousands of spin offs we see in everyday life. None of us think of where they came from, no one thinks of life without them. Yet none would have existed without the space effort.

I've not even talked about what weightless means to drug manufacturing or to phyisical properties in materials that can not be made here on Earth.

[MSL]

 The caveman example is something like litotes (http://www.oxforddictionaries.com/definition/english/litotes), but I took it literally and used it as a base for my extensional examples (comparisons), because I want to emphasize how some people/communities do not develop their potential, because of religious reasons. Some calls them 'ahistorical' people, because they stay in one and the same level for centuries or longer. (That's why 'Why only cavemen?' was a rhetorical question.)
 I haven't something else to add about the rest of your reply, but I want to share something a bit off-topic and to ask about your opinion:
 It was in the early 80's. I listened to a translated Soviet science radio show in which the ordinary Soviet citizens asked questions and got answers. I still remember one question (but not the answer), because it was, I think, a very genial question. A man asked: "Can we cover the Moon surface with mirrors and then to use the sunlight in the night?" If it's possible, do you think it'll be useful to have some additional days every month? (If it's a mirror-covered Moon, during the Full moon lunar phase, it will be maybe 70%+ daylight bright here, on Earth.)
 (I see you have another reply; I'll see it and answer it next time, because I'm a bit busy right now. Now I'll post only this one.)
 

[mojo]

I'm having a bit of a problem with understanding why we might want to cover the moon's surface with solar collectors. To me, it just doesn't make sense. What have I missed?

[MSL]

I'm having a bit of a problem with understanding why we might want to cover the moon's surface with solar collectors. To me, it just doesn't make sense. What have I missed?

Ah, it's not solar collectors, it's MIRRORS (https://en.wikipedia.org/wiki/Mirror). His question was about why not (what if) the Moon is covered with ordinary mirrors. Then they reflect the sunlight and we have a brighter Moon (like a second small Sun). I wonder if this may be beneficial for the Earth (like more 'daylight', more Solar energy) or it will just disturb the environment?

[MSL]

 Good afternoon! Let me read now the rest of it and to say something, as I promised yesterday.
 I see the point. I know sometimes in the fundamental science there are surprises -- you're searching for some A or B, but you end up discovering X or Z. I don't exclude the possibility searching for extraterrestrial life, mankind finds another source of energy or something else.
 I don't mean to solve all the problems on Earth. I meant that it's much better at first to focus and to concentrate money on medicine (for example -- the nanorobots that may cure everything and to have some day panaceic nanorobot). I think it's less costly, too. But there are opinions that the Earth will be (or 'is already') overpopulated and it's not necessary to have medicines, it's useful to have more wars, more death cases and so on neo-Malthusianism. (There are even conspiracy theories that some viruses and others are artificial and they are produced just to kill more people, etc.) If something like this is true (for instance, if the elite that has the power to decide the budgets really thinks that we're already overpopulated and we need only to think about birth control and more resources), then what I speak here doesn't matter and it's just an ideal.

[mojo]

We don't really need the moon to provide light at night. The Town That Created Its Own Sunlight. We don't really need the moon to provide light as has been shown by this town.
I question whether the moon would actually help all that much. Mainly because of the Inverse square law would take much of the benefit away before it got to us. Still there would be enough on clear nights to provide a good illumination at night.

What would be the problem would be getting those clear nights in the winter especially in many parts of the globe. Another issue with that would be long term. Plants do a sort of hibernation over night to conserve their energy for when the sun comes up. Providing light while plants around the night time side of the Earth could well give us unexpected results. Like maybe the corn quits growing without a night of rest.

There are some indications that plants, animals, and other living creatures don't just evolve over long periods of time but also at times evolve rather quickly given changed enviroment.

[Gay]

It's a very interesting thread. So useful information. Thank you, thank you!

Mojo didn't put any link in the 'Town that creates its own sunlight' and I edited it with this knowledgenuts.com link. If he want me to change it with another link, just tell me.

[MSL]

 Thanks for your answer! I was thinking something like these you mentioned above. I like the way you describe it. Good answer.

[Alexa]

So far... no aliens.

[mojo]

If he want me to change it with another link, just tell me.

Actually I had intended to link to that page. I'm still getting used to this new track ball mouse that replaced the old one. In particular, it seems my co-ordination only hits once every 5 seconds with it. I've had to change from drag to highlight to click, drag, click, in order to capture those links as a result. That takes some getting used to after all these years of doing it differently.

So thank you for covering my screw up, Internet!

[Gay]

My pleasure.

That nonorobotics technology is an interesting topic. We see it in a post above. What do you think about it?

[mojo]

One of the advantages of new tech is almost always it allows you to do things never before possible. The applications that nanorobotics could open up are still on the drawing board. Until the technology matures, there is no telling where this will take us.

One of the tin foil hat groups will tell you of the fear of the grey goo. Basically technology gone berserk and without control.

One the other side, medical techniques such as have always been considered impossible because of that lack. Remember the movie, Fantastic Voyage? Instead of reducing an entire submarine crew along with the machine, what say we just do away with the crew and the machine. Instead you use nanotech to do the job. Or say cancer, where you have a vaccine that is only used if it is needed and exactly where it is needed as opposed to sending it everywhere through the body just to get those few offending cells. Many of the complications resulting in toxic type materials used in such vaccines would no longer be needed to be filtered out by the kidneys, removing putting those organs at risk.

Another foreseeable possible, is something akin to a Von Neumann machice. When you send a population to Mars, they don't have to bring any construction equipment with them, because when they arrive, the things they would have build for living quarters, machine shops, excavators, and the like have already been built and are waiting on them to just move in. Along with a store of water and oxygen.

The idea here isn't to send the equipment ahead of the arrival of the colonists. It's to send a very small package of self replicating bots in nanosize. At first the bots make copies of themselves which in turn make more copies, till there's literally a factory of nanobots. Then they start making specialized bots that do just one thing, and then more that do something else. At nano size or smaller, they could mine the planet without having a mine. Creating machines able to break down molecular compounds into elements to reuse to create other compounds needed for such construction. Some where in all this would be needed a master program or plan on what to build when, how much is enough, when to schedule the altering of replication into specialized nanobots for certain tasks and when to do it. But theoretically, what you could pack into a 5 gallon bucket would be enough to start it all, given time.