What is life? Depending on who you ask, the answer you get might be scientific, religious or philosophical. But if you take a look at it from a physicist’s point of view, you might be able to understand the universe on all levels. Why? Well, from its explosive start, the universe has evolved and, along with it, humans have too. Everything in the universe is essentially made up of particles – they’re just arranged differently for different things.
But, that is not the only unifying property between humans and the universe. Both are also subjected to the same forces during creation and destruction. Physicists have already explained the big bang, but do you know how they guess the universe will end?
In this summary readers will discover:
- Entropy and the creation of the universe
- How humans evolved and adapted for survival
- How the world will probably end – and be re-created
Key lesson one: Entropy and the creation of the universe
In physics, entropy is defined as the measure of the amount of energy that is unavailable to do work. The amount of entropy is also a measure of the molecular disorder or randomness. The higher the entropy, the more disorderly an object is. Most objects in the universe exist simply because of entropy. However, the second law of thermodynamics states that there is a natural tendency for things to degrade into disorder. This means that everything in existence has a tendency to move into a higher state of entropy. To put it simply, the only certainty in life is death.
Since everything in the universe is made up of particles in a highly organised and thus low, entropy state, what is keeping them that way? If there is a tendency to move toward disorder and a high entropy state, which, by the way, is the most common state for particles in the universe, how exactly does everything exist the way that it does? Well, it all started with a big bang 14 million years ago.
We know that the big bang was the beginning of the universe but do you know what caused it? One theory, thanks to one of Albert Einstein’s theories, is the repulsive force that gravity has. This was contrary to popular thought at the time which believed that gravity only had an attractive force. But, if we considered a small region of space filled with dark energy which has no formation, it is most likely that the gravitational force would be repulsive. This would cause an explosion of this small region of space causing it to expand. Does this sound like something familiar? The big bang caused the dark energy present in that small region to be transformed into a mist of particles that created the universe. Some areas were denser in particles than others which, of course, lead to a gravitational pull that pulled more particles towards these dense areas. These clumps of particles grew dense and hot causing the nuclear reactions which created stars. The creation of stars is essentially a move towards greater order within a gaseous core and hence, a lower entropy state. This decrease, however, is exceeded by the increase in entropy outside the core which is in line with the second law of thermodynamics. We now know that the natural tendency towards higher entropy in the universe is driven by gravitational and nuclear forces. The low entropy organizations that we are familiar with use these forces to maintain their states and balance. This is what led to the creation of planets and life.
When a star dies or collides with another star, heavy elements are released into space. It is here, that they combine with other elements which are present to form new stars and planets. The sun is thought to be such a product – created from the first stars and as a by-product of the sun’s creation, the planets of the solar system came into being. Elements that could withstand heat better clumped together to form Mercury, Venus, Earth and Mars whereas the lighter elements gathered in the cooler outer regions to form Jupiter, Saturn, Neptune and Uranus. Earth did not have an easy start though, it collided with the planet Theia. This collision caused Theia to shatter, the Earth’s crust to vaporize and tilted the Earth on its axis. The remnants of Theia became the beginnings of our moon. This series of events led to life on our planet as we know it. The tilt in the earth allows us to experience seasons, the moon controls the tides of the ocean and this collision ultimately formed our oceans. It is in the water of the oceans that life began.
Key lesson two: How humans evolved and adapted for survival
Humans are made up of particles and governed by natural laws just like the rest of the universe. However, the way we experience things and feel emotion is something different. The brain collects and collates data without us even being aware of it. When we experience something, it is a result of different intakes of data being simultaneously stitched together in our brain. This is why everyone’s experiences are unique. The fact that your brain is continuously working to achieve this means that it is always active and your thoughts are not as much your own as you think it is. The concept of free will is false. There are physical processes that occur in your brain – shifting particles that govern thought and the decisions that are made.
In addition to this unconscious processing, the development of language in humans contributed greatly to the success of our species. But, why exactly did we start speaking in the first place? There are actually multiple theories that exist as to why it happened. From it being an extension of social grooming that happened to maintain bonds between individuals, to a survival tactic to warn others of danger. However it came about, it led to one of the most influential human behaviours – storytelling. Storytelling helped spread the word amongst humans, helping them learn from the actions and experiences of others. This in turn strengthened their ability to recollect, to act as a result of what they had heard what to do.
This was the beginning of human intelligence and as intelligence grew, our ancestors developed tools, began farming and life became much easier. Then came the inevitable, humans began to question life. Why did things happen the way they did? Where did everything come from? Why did certain events occur? Religion or a belief in a higher power seemed to answer these questions at the time. If there was no way to explain it, there must have been a higher power involved. Religion evolved to bring groups closer together outside of their familial unit. It succeeded in allowing groups to feel as if they were a part of the same family because they share the same beliefs. This group mentality provided a safe environment due to religion normally implying that good behaviour would be pleasing to a higher power. It also led to an environment conducive to reproductive success as potential mates would be ‘religious and therefore good. Religion also helped humans in one more way. It made death easier to handle. If you weren’t worried about dying, you could focus not only on surviving but thriving.
As religions blossomed and myths and storytellings continued, humans began to do something else. They began to make, and appreciate art. The reason for this, once again, is not set in concrete. There are many theories that exist. Firstly, it could have been purely aesthetic, something different and nice to look at. Secondly, it could have aided in sexual selection. This theory is a bit far fetched, but just like the mating rituals of animals, maybe art developed to impress potential partners. Lastly, a theory supported by most scientists suggests that, once again, this behaviour contributed to human survival. Art could have reinforced bonds within groups by promoting social interactions and creating healthier and happier societies. And, we all know that a creative mind is able to solve problems easier.
Key lesson three: How the world will probably end – and be re-created
As humans continue to evolve, one thing is clear – death is inevitable. The forces of evolution and entropy continue to work to keep life as we know it stable. But how long will this stability last? And what would instability bring about?
Well, the theory goes that the sun should remain stable for the next five billion years before its core will begin to implode. This implosion will cause a huge increase in temperature that will affect the planets. Nearby planets will be vaporized and if the earth survives, chances are the oceans would dry up, and its crust turned into lava due to the intense heat. It will take the sun around 600 million years to stabilize before another implosion causes a white dwarf star to remain for a couple of billion years before turning into a dark and frozen sphere.
The earth, of course, will continue its orbit long after humans have died out before eventually being pulled into the dead sun. These deaths of large stars lead to the creation of black holes which will suck everything in its vicinity into it due to its growing gravitational pull. A black hole at the centre of the galaxy has the potential to grow until it can consume the entire galaxy and universe.
But, just as black holes form, they should disappear at some point. And, with their absence, there is a chance that life may someday start again. Space is not just space, it is filled with dark energy and as long as there are particles in the universe there is potential for life. It may take a very long time to happen given that we do not know the true extent of the universe, but if it happened once, surely it can happen again. Maybe it already has.
The key takeaway from Until the End of Time is:
The beginning of the universe and the forces that created it are fascinating. The presence of particles and the fact that they are affected by the same forces guarantee one thing – the inevitable degradation of all matter. Just as evolution is necessary for creation, so too is entropy for destruction. Humans have evolved along with the universe, each step making our lives easier and ensuring our survival. No matter what though, the universe will come to an end at some point. Nevertheless, we cannot forget that every new beginning is some beginning’s end.
How can I implement the lessons learned in Until the End of Time:
Just like our ancestors used religion to help deal with death better, try not to concern yourself with your mortality. If you spend your time worrying about your death or the death of your loved ones, you prevent yourself from truly living and experiencing life. Also, try developing a creative outlet to help develop a healthier and balanced lifestyle. This will not only make you happier but also allow your brain to function clearly and problem-solve with ease.
