Modern observations show that the universe appears to be expanding, and that about 13.7 billion years ago it was much smaller and hotter. As it expanded and cooled, hydrogen and helium condensed out of the initial soup up of high energy particles. Massive clouds of hydrogen compressed by gravity gave birth to and fueled the stars. All of the elements heavier than helium are produced in fusion reactions that power the stars. The heaviest elements that make up the Earth and other rocky planets are remnants of supernova explosions of hot white stars.
Life on Earth is dependent on the debris leftover from one or more of these supernovas that occurred more than 4 billion years ago. Our bodies are about 90% stardust, and 10% hydrogen left over from the origin of the universe. Billions of years of evolution have resulted in biological organs, our brains, that have the ability to comprehend and appreciate their own existence. Our brains control a network of nerves that can animate our bodies, and experience the universe through our senses. At some point in the evolution of life on Earth our universe became self aware via unique arrangement of primordial hydrogen and stardust.
Are we Unique?
We don’t know if humans are unique in their awareness of the universe. There is some indication that some of our animal friends are aware of themselves, and a lot of evidence that they are aware of their surroundings. This is a question for another post, since subjectively we can’t prove that any individual other than ourself is self aware. It can all be in our heads and nothing else may exist. However, our objective reality tells us that our parents were here before us, and if we are fortunate our progeny will be here long after we are gone.
Higher animals, the ones with complex brains, have been around for a few hundred million years. If life is unique to Earth than the universe has been self aware for at most 3% of its existence since the origin of time.
Astronomers at the University of Auckland claim that there are actually around 100 billion habitable, Earth-like planets in our galaxy, the Milky Way, and there are about 500 billion galaxies in the universe. This means there may be somewhere around 50 billion trillion 50,000,000,000,000,000,000,000 (5×1022) potentially habitable planets. Half of them old enough for life to evolve. If life is possible on 1 in a billion, then there may be 25 trillion planets with complex brains inhabiting them, but we don’t know and we may be the only ones.
The Evolution of Intelligence
The origin of life is one of the important unsolved mysteries in science. Prof. Douglas Theobald of Brandeis University used computer models to show with overwhelming odds that all life on Earth evolved from a single celled organism that lived 3.5 billion years ago (Nature. 2010 May 13;465(7295):219-22.), which is very soon after the Earth became habitable. It may be inevitable that once a planet is habitable life soon appears, and complex neuro-systems follow. Evolution is a powerful driver of change. Once there are trillions upon trillions of one cell microbes sloshing around in a planet’s hydrosphere, all mutating and evolving, it may be hard to prevent animation from eventually happening.
Competition rewards creatures that can adapt, and the ability to process information and react provides an adaptive advantage. It took about 3 billion years for animated creatures with complex brains to evolve on Earth. Symbolic thought processes on Earth have been around for the last 0.001% of the age of the universe. The big mystery is how did it all start? It could be a one time accident. Without knowing this any estimate of life on other planets in the universe is a guess. All we can say is that there are between 1 and about 25 trillion planets inhabited by creatures that are self aware.
In summary, the universe has become self aware through the process of a hot sudden expansion that cooled and resulted in the production of stardust that collected into planets that gave rise to one celled organisms that evolved neuro-networks that became aware of the universe. I left out some steps, however, there should be no doubt in anyone’s mind that the universe has became self aware through us, and is striving to find out everything that can be known. In the process of becoming aware, the human mind has evolved with a tendency to believe itself as an awareness apart from the universe. It has developed a conflict in the form of self interest, which biases its awareness of objective reality and the truth.
Is their a collective awareness? The Gaia hypothesis, proposes that organisms interact with their inorganic surroundings on Earth as a collective organism. In this sense the universe has a lot of sensory input just from the creatures inhabiting Earth.
The Search for Knowledge
The point of all this is to filter the numerous opinions and news reports that flood the media and the internet everyday, and to avoid the trap of self interest that clouds our ability to see the truth. The reason there are radical liberals and ultra conservatives with diametrically opposed perceptions of the same events is an example of self interest clouding their ability to be objective. They are unaware that they are just animated stardust subjectively perceiving the universe they are part of.