Cosmic horizon: Beyond the edge of observable Universe

There are a lot of us who have one time or another entertained the thought of trying to un-puzzle the mysteries of the universe; and then there is a portion of us who remain for ever inquisitive about the origins of everything that crawls or moves or flies because it has a life and wondering why and how come that we do not have all the answers about life itself. As for the galactic and the majestic skyline, we, as a population of the planet earth; the humans, are still trying to understand or rather, learn and solve the unknown equation of the beginning of the vast universe. Yes, most have tried to read the maps of the night sky with telescopes or binoculars and other primitive instruments like the ancient astronomers but with modern instruments that only adds foggy images in our minds with limited answers. There is a moment, in a dark field within open spaces in the cities or far from any town, when the Milky Way stops being a photographic foggy image and starts being a place. As a child and now as an adult I have had that moment more times than I can count, lying on my back in the damp grass of many places and more frequently by Hyde Park in central London not far from my house by South Kensington tube station and trying to study the night sky. To put it bluntly, the stars do not care that I am desperately trying to study everything within sight and more or should I dare say, mapping the sky. They simply shine, and I simply look, and somewhere in that exchange the questions begin to form—not as tidy academic enquiries, but as a kind of gravitational pull. What is out there, beyond the galaxies we already know? What is beyond the edge of what we can ever see? And if we found the ruins of something ancient and intelligent, something that rose and fell before our solar system was even a cloud of dust, what then would we do with that knowledge?

I did not set out to write a book about any of these, I set out to understand it for myself, because the questions would not leave me alone. The more I read, the more I realised that the material was scattered across disciplines that rarely spoke to one another—cosmology, archaeology, theology, engineering, philosophy. Each had a piece of the puzzle, but nobody was putting the pieces side by side. The cosmologists were mapping the observable universe with astonishing precision, yet their maps stopped at a boundary they admitted was arbitrary. The engineers were dreaming of starships, yet their dreams kept crashing into the hard wall of physics. The philosophers were debating the meaning of humanity's place in the cosmos, yet they rarely engaged with the actual data from telescopes or the actual constraints of propulsion. I wanted a single conversation that held all of these threads at once, and I could not find it. So I started having that conversation with myself, in notebooks and on long walks, and eventually I decided to invite you into it.

I have attempted to inform the reader cautiously that this book is written by a curious amateur, not by a credentialed expert, and I want to be honest about that from the start. Some people will see that as a weakness. I have come to see it as a strength, because expertise can sometimes build walls as well as bridges. After reading a lot about this subject, I have noticed that the expert knows what is known; the amateur is free to ask what is not known, and to ask it in plain language that does not require a doctorate to parse. There is a tradition of this, and I take comfort in it (ha ha ha), The great questions of the cosmos have never belonged exclusively to the professionals. They belong to anyone who has ever looked up at the night sky and felt a pull toward something larger than the self. I am writing for that person, and in fact, I am trying to comprehend the whole quagmire and hence, I feel that I am that person.