If the number of advanced civilizations is perhaps high, why aren't all the galaxies lit up with the light of these civilizations? Some say the time of outward radiance might be limited by the same tech we use of lower energy connects like WiFi and wires that no longer emit radiation (I Luv Lucy always will be zooming her shows at the speed of light orange radiance waves out to others who may say, Rise and shine on other worlds, just like here, yet more! "Did you make this up"?) Even so about the light from worlds with advanced machines, like 257 million stations, just as lots of pollution is emitted by chemical synthesis, ect. I find it hard to believe that advanced civilizations wouldn't have light pollution. Extra energy is needed for an advanced society to be advanced and light is not so expensive, It's just light. Strike a match, and you have much. Accidental leaks would be common. At any rate many advanced civilizations might leak light as part of common business of life.

 On the other hand I believe as Carl Sagan said that advanced civilizations might have a way to conceal themselves from us. I think this is possible by way of Einstein's EPR, "the spooky action at a distance". There is evidence for the EPR, and I believe it may be because the lower energy fields being a bit lighter than light may have a phase change, or ect. and go faster than light. It's lighter than light so may move faster than light. This is my hoped for Generalization of Maxwell's Method.

  I believe if we take an initial low amplitude source of the waves and then focus them on the distant realm where we or others might hope to smooth the light, we might be able to render it less obvious to outside sensors. Note that the light would be lower energy than the phase change from emission to the light zone we hope to edit, thus travelling faster than light for most of it's travel, catching up with the light at higher speed. Only when the zone where the waves are focused is reached would the "virtual" light be real, as in a laser light at a concert. If the musician at a heavy metal show says, what's making all the noise in here! One problem with using this method might be that the others might also find the high speed waves too, but then so could we, and use this also to find them.

I believe in the EPR enough to consider this, at least till more experiments are done to completely prove or disprove Einstein's idea.There are new experiments being engineered to find out. Even so it may not be possible, in which case, we may indeed find lights of advanced civilizations without them all being with too many editors, no crosswords, all shall be well!

So too even though I believe even if faster than light starship travel may be possible, it may never be economical. To move a lighter mass like a wave faster may be much easier than a massive starship, because of no phase change. The mass augment of SR seems to come from friction, more speed, more resistance, more mass. Einstein believed not that faster than light was impossible, just that only waves or masses already moving at  FTL could move at that speed. I would think he believed in the EPR because he realized intuitively that the EPR is lighter than light so it might be FTL. If friction slows a massive starship, this may be much tougher to untangle from the field, and so it would have a high cost to an advanced civilization to colonize other planets, perhaps too high to be viable. Faster than light for some mass doesn't mean it will be cheap for all. Even so I've believed like others that we might be able to smooth these field interactions, in essence reducing friction by using part of the wave like some torpedoes go much faster by pumping exhaust to the nose and this smooths out the wave so the machine is faster, yet it still may not be either or or only moderately cheap.

There are those who calculate that it would take a telescope millions of times larger than the Hubble to see the lights of the cities of advanced civilizations. For lower energy radiation like microwaves, I had proposed using using either Jupiter's field which bends the waves around or magnetic bubbles (filled with gas to bend the waves; magnetic fields alone don't bend the waves).
Even so light is "heavier", and not so easy to bend.


HOW TO FIND THE LIGHTS OF DISTANT SHORES

 I propose we send out beams of light in a great wheel of the light ray that forms the sensor of the telescope. Like a laser, these are set up in their rest frame as standing waves. By using two slightly overlapping waves, the waves are balanced so they have internal cohesive tension.The tension acts to multiply up the incoming light's effect on that point of the ray. It could be tuned in frequency to refract light the right amount to the sensor. Light at high energy behaves like a heavy particle so one or more a standing waves would be like a lense of considerable density. The telescope observes the ray as it sweeps out 360 degrees at a suitable distance, and the ray's increased sensitivity observes the distant star, planet, or other lights. This could make huge cheap telescopes possible.

I believe advanced civilizations are rare for three reasons; rarer than some have believed.

Overcrowding caused by over hunting of evolution's innocence, causing increased competition for decreasing resources, causing stress and unnatural illness also, reducing the civilization. After all, competition and resources are at the foundation of territory. History shows that people who lose their land are gone in history. Click Here  for Complete Page. I think this may be the main problem most advanced civilizations may face. Competition and Resources are simple. On the link I list ways we might reduce the overcrowding gradually without so much grief.

Second, new research shows that giant gravity at the center of each galaxy makes only a zone about halfway out where life has time to evolve.Too far in too much radiation for life. Too far out no stars forming by the radiation and plasma ect. This means there is a smaller zone in each galaxy where life or advanced civilizations can exist. A reduced zone means perhaps 2/3 reduction in advanced civilizations too.

Third, It's believed the moon was captured. With no moon, no tides and less volcanoes, so less water. Most life lives today within five miles of the ocean. 99% of the fish are 5 miles from the shore tho most not inland 5 miles or land fish, saying, "All ashore that's going ashore!". 3/4 of the people are by the shore. Life is believed to have started in estuaries with the tide sloshing in and out like a computer. With no moon, there would be less lava so less steam via the moon's influence on volcanoes. (2/3 not 1/3 of volcanoes are within the first 10 days of of the month, more earthquakes too are in spring and fall, when tides are higher, and so on.) Less water and less water and nutrients sloshing in and out of tidal pools computing cycle after cycle to form life. Less life, fewer advanced civilizations. The moon may have also brought the world out of ice ages in ways not found  on other worlds by not allowing it to form large ice caps and not tilt over permanently, at least if the Earth like future advanced world already has enough spin to right itself by way of the moons spin. The moon is unusually large (1/81 the earth's mass) and so these worlds with just a bit less spin than enough even if with the unlikely moon capture would become tidally locked. Tidally locked worlds are known, and some are so hot on one side the rocks melt then condense on the other side, literally raining molten rocks if there were weather reports on these worlds.

I believe it would be improbable to have a moon so large compared to Earth, unlike other "families of planets in the solar system"click here for why.