Billions of years ago an extraordinary event occurred without which nothing would exist. It was the beginning of the universe. It was the moment when a large amount of energy in an infinitely small space expanded violently and led to the creation of the universe and everything we see around us today. Understanding the history and nature of the birth of the universe can perhaps be considered the greatest scientific achievement. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay There are various views on what happened before the Big Bang, however it is a very important question. Astrophysicists argue that there is no answer to what happened before the Big Bang, however several theories exist. It is supposed that we can hypothesize because there are no tools to reach the truth. A profound and easy to understand question is the distinction between whether the universe is finite or infinite and this in terms of time and space. Other questions include whether the universe continues forever or has a limit? These questions have been asked for centuries. Archytas, Plato's colleague, said: “Imagine a warrior with a spear at the edge of the universe, and he throws the spear. Do you imagine it going on forever or hitting something and recovering? If so, what is the limit? This brings us to two possibilities, either the universe is infinite or it ends, and if it ends, what is the end? Cosmologists face the same question. When Copernicus replaced the geocentric model with the heliocentric model, it was a revolutionary move and not just an astronomical one. These ideas were incomprehensible and highly questionable in the past. The Statue of Giordano Bruno in Rome was burned at the stake by the Catholic Church not only for believing in an infinite universe but also for believing in the existence of countless stars and planets and the life around them and perhaps even in people. The next venture into the infinity of the universe was by Isaac Newton who postulated an infinite universe that was infinite in extent, time and space. He was followed by Wright who imagined infinite inhabited worlds in the universe. But this was difficult to believe conceptually. It was so because, in an infinite universe every lateral line must end in a point of light, be it a star or a galaxy. As the light from each star decreases by the square of the distance, the number of stars increases by the same factor. And so, logically, the night sky must be as bright as the day sky in an infinite universe. This was a paradox that Newton never resolved. So, it took us more time to understand how exactly the universe works and to resolve the paradox. Galaxies were once considered “Island-Universes”. Isolated realms of gas, dust, and billions of stars separated by unimaginably distant distances. In fact, no galaxy is an island, as researchers say, galaxies prefer company. The gravitational pull of a large mass of galaxies attracts nearby galaxies of similar size and smaller. Galaxies can bring together hundreds or millions of them to form a huge cluster. Another dichotomy arose when it was debated whether the Milky Way, the star system we inhabit, was the entire universe or whether other island universes existed. Herschel tried to map the universe which he knew was vast. But at the beginning of the 20th century, two very different ideas were in play. In one of them, the fuzzy nebulae were hypothesized to be star systems as distant as the Milky Way, perhaps hundreds of thousands of light-years away. However, the accepted compensatory model stated that these fuzzy patches of light were simply star formations within our great galaxy that was the universe. The problem was solved by EdwinHubble who made the revolutionary discovery by astronomically measuring the distance to a few dozen galaxies. By the end of his career, he had extended the size of the known universe by a factor of a thousand. The universe is made up of dark and mysterious material compared to the light and visible things we are familiar with called dark matter. Astronomers are confident that dark matter really exists because the law of gravity has passed many tests, and if we add dark matter into computer simulations, we evolve large-scale structures that look just like our universe. In 1964, by chance, cosmic background radiation was discovered as a relic of the early universe which, together with other observational evidence, made the Big Bang the accepted theory in science. Recent observations even seem to suggest that the expansion of the universe is accelerating. The Big Bang can be described as all space extending everywhere at once. The universe wasn't expanding into anything, space was simply expanding into itself. The universe has no boundaries, by definition, there is no outside the universe. The universe is everything that exists. In this hot, dense environment, energy manifests itself in particles for only very brief moments of time. Pairs of quarks were created from the gluons which destroyed each other perhaps after having emitted other gluons. These found other short-lived quarks to interact with, forming new pairs of quarks and gluons again. Matter and energy were not just theoretically equivalent. It was so hot that they were practically the same. Somewhere around this time matter won over antimatter. Today we are left with all matter and perhaps no antimatter. Instead of a single commanding force in the universe, there now existed several versions of it that operated by different rules. By now the universe has expanded to a diameter of billions of kilometers, which leads to a decrease in temperature. The cycle of quarks born and converted back into energy was suddenly interrupted. Quarks began to form new particles such as protons and neutrons. There are many combinations of quarks that can form all kinds of hadrons, but only very few are very stable for a reasonable period of time. The universe, having grown to a hundred billion kilometers, was then cold enough for most neutrons to decay into protons and to form the first atom, hydrogen. The universe can be imagined as an extremely hot soup, ten billion degrees Celsius, filled with countless particles and energy. Over the next few minutes things calmed down and settled down very quickly. Atoms made up of hadrons and electrons that create a stable and electrically neutral environment. Some call this period the dark ages because there were no stars as the hydrogen gas did not allow visible lights to move. When the hydrogen gas clumped together after millions of years and gravity put it under great pressure, stars and galaxies began to form. Their radiation dissolved the stable hydrogen gas into the plasma that still permeates the universe today and allows visible light to pass through. Finally there was light. However, while we talk about what happened at the very beginning, i.e. the Big Bang, we don't know what happened there at all. Our tools break, natural laws stop making sense. To understand what happened there, we need a theory that combines Einstein's Relativity and Quantum Mechanics, something countless scientists are currently working on. But this leaves us with many unanswered questions. Did universes exist before ours? Is this the first and only universe? What started the Big Bang? Or did it occur naturally? Keep in mind: this is,.