The Science Behind Time

Kofo Babalola

Time is an abstract phenomenon that keeps the human race moving. Time never stops but keeps passing by. Time is an illusion that shapes and forms our past, present and future. The foundation of the Earth was created on time. For it is written in Genesis 1:14, ‘And God said, Let there be light in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years.’ The concept of time was created for humanity by God to be a form of structure of life. It gives us a reason to wake up in the morning with the sunrise and to sleep at night as the sun sets. The daily cycle of the rising and setting of the sun in the sky repeats continuously to form the seven days in a week; approximately four weeks in a month; and the twelve months in a year. This is looking at time from a higher level. Time can be broken down into smaller units as there are twenty-four hours in a day, sixty minutes in an hour and sixty seconds in a minute. These are measurements of time that can be broken down even further to the smallest unit of time known to be the zeptosecond which is one trillionth of a billionth of a second. However, the average human being doesn’t measure time up to this point.

The illusion that is time is measured differently on Earth than in space. This was first explored by Albert Einstein in 1905 through the ‘Theory of Relativity’, which explained that the difference between time in space and on Earth was due to the effects of gravity and relative motion. These effects were based on the principle of time dilation where time appears to move slowly or quickly depending on where one is situated within the gravitational field. This means that clocks that are closer to massive objects such as planets or stars will move more slowly than the clocks which are further away. Therefore, time will move more slowly on the planet Jupiter than on Earth because it experiences a stronger gravitational pull as it has a greater mass than Earth. Where gravity is stronger, time passes much more slowly.

Time dilation also explains the reason for ageing less when travelling in space than on Earth. According to the theory of ‘Special Relativity’, the faster you move through space, the slower you move through time. When one is in a spacecraft that is propelled into space by a rocket, travelling at even a fraction of the speed of light, time appears to slow down more significantly as opposed to when one is stationary on Earth. Travelling closer to the speed of light in space makes this effect even more noticeable so one ages much less than those on Earth as less time would have passed by for them in space. This concept of time dilation leads to the ideology that time stretches and contracts to form a malleable fabric called space-time which massive objects such as the sun and planets bend to wrap around themselves.

The act of bending space described by Einstein’s theory provides a way to alter time which allows one to believe in the possibility of time travelling into the future through wormholes – that is a bridge linking two distant points in space together. The possibility of turning the clocks to propel us into the future and into a different era becomes possible through the lens of scientific geniuses like Einstein.

The reality of time travel is yet to be proven but this hasn’t stopped film-makers from allowing their imaginations to intersect with science to create artistic pieces that play on this concept such as the 1985 blockbuster film, ‘Back to the Future’, written by Michael Robert Gale and Robert Zemeckis. The directors explored this scientific theory of messing with time through the fictional characters of Doc Brown who invented the time machine that took him and Marty McFly on an adventure to rewrite time. This film took it a step further past the realms of Einstein’s theory as it allowed the characters to not only time travel into the future but to turn the clocks back in time to the past to alter the courses of their lives. This twist in the laws of physics challenges the scientific minds of those who theorised the ability to only travel into the future and not the past thereby pushing physicists such as Kip Thorne to provide evidence to back this claim of travelling into the past. This has sparked debate as this claim of reversing time was forbidden by the greatest scientist of recent times – Stephen Hawkings – and thus is yet to be proven with concrete scientific evidence.

What is known for sure is that time is speeding up as the universe gets older. This has been scientifically proven by researchers looking at data from supermassive black holes in earlier galaxies. In the beginning, the universe was moving in ‘extreme’ slow motion, but it has been discovered by scientists that over time it has dramatically gained speed. There has been evidence of space expanding which has made our observations of the earlier universe appear much slower than the flow of time today. This is the reason why time appears to be moving faster. The question now lies in where time will eventually end up as the universe continues to expand. Will there be a point where time will expand so far that information will no longer reach us here on Earth? Will we end up disappearing from existence and will everything around us be consumed by the darkness of space? What happens when all the lights of the night sky fade into the distance? Will that be the end of what we call life? Despite the uncertainty of what takes place in the universe, we hold onto what we know that is, we have a God who is in control of the great force, gravity, that determines time here on Earth and in the outer regions of space.

•Babalola is an Engineer at GE Aerospace