Creative Speculation

if they exist at all. Finding planets that could likely support some kind of life is probably hard. Finding planets with intelligent life is probably very, very hard to find. In the 4 billion years of Earth's history, intelligent human life has been here on the planet (that we know) only for the tiniest fraction of time. Finding planets with intelligent life that have managed to become space-faring cultures on a grand galaxy wide scale is probably quite rare.

But there only has to be one. The Milky Way has existed for over 13 billion years. There are more than 300 billion stars in the Milky Way. I'm not a mathematician but I would guess that there would be at least a very, very likely chance of at least one very advanced, very old civilization among the billions of possibilities. One intelligent civilization more than a billion years old might have had time to evolve into that Type III civilization according to the Kardashev scale, the one that Michio Kaku and many other scientists describe as one that has harnessed extreme types of energy such as a Dyson sphere (harnessing the energy of a star) and even of a supermassive black hole. That level of energy would probably allow for space travel approaching the speed of light and many other things we haven't dreamed of. Members of such a civilization probably would have long shed their organic bodies and done away with such things as lungs, a heart, and a circulatory system as it allows only life in a very narrow zone and is too prone to dangers and inefficiencies. Those beings probably long-ago melded with and evolved into machines and the machines themselves resemble organic structures, not rigid and heavy metallic structures, but flexible, lightweight, and adaptable and self-regenerating (like organic skin, muscle, and bone) bodies. The members of such a society may have become virtually immortal and may have evolved into a group mind, no longer existing as independent thinking entities. Space-faring cultures of a billion years of age and more would probably have long left their original planet and found themselves at home in deep space. Such old cultures would long ago have set about to exploring all parts of the galaxy and, given the exponential spread of their kind over a very long period of time, eventually made their way to all 300 billion stars of the Milky Way.

I think it's very likely that at least one such old and very advanced civilization exists and that it have spread throughout the galaxy just as humankind has spread throughout planet Earth. My doubt however is that they have actually come to Earth, although they would surely be aware of it. That's why I marked "not sure".