Since time immemorial, people have been entertaining themselves by retailing and detailing stories and listening to anecdotes narrated by others. Among them are stories about how everything in the world started. Most of them are religious creation myths and some others, irreligious folklore or urban myths without a semblance of realistic grounding anent scientific temper.
But there is one story, propped up by evidence, for us to say that it is our own story and the best story any one has ever told. The story reveals how everything, including us: humans, came about almost or perhaps, literally from nothing. The story is mind-blowing, but not mere fiction.
People have dibs on fact or fiction stemming from what piques their interest, but evidence is staring in the face of the discerning people that societies progress by leaps and bounds when people take their decisions individually and collectively predicated upon empirical evidence if science-based advancement is any comparator of social progress.
Empirical evidence
 The timeline of the universe |
The primacy of empirical evidence for progress, socially or otherwise, is undergirded by the modern scientific edifice, as attested by 20th century legendary cosmologist, Prof. Carl Sagan’s axiom: “Claims that cannot be tested, assertions immune to disproof are veridically worthless, whatever value they may have in inspiring us or in exciting our sense of wonder”, corroborated by 18th century philosopher, David Hume’s maxim: “A wise man proportions his beliefs to the evidence,” and in character with the pristine doctrine of the greatest of all sages from the sixth century BC, Gautama Buddha, whose Kalama Sutta among other things, posits: “Do not believe in anything simply because you have heard it. Do not believe in anything simply because it is spoken and rumoured by many. Do not believe in anything simply because it is found written in your religious books. Do not believe in anything merely on the authority of your teachers and elders. Do not believe in traditions because they have been handed down for many generations. But after observation and analysis, when you find that anything agrees with reason and is conducive to the good and benefit of one and all, then accept it and live up to it.”
Hold your horses! Philosophising on the efficacy of the empirical method in the epistemological domain aside. To ponder that epic story, first look up and see what is out there.
You see the vast cosmos teeming with billions of stars and galaxies. Turn back the clock over 13 billion years, and our universe was a very different place. Back then, it was so small that it could fit inside the palm of your hand. From this infant universe, everything would be created: stars, galaxies and building blocks of life itself, calcium in our bones, iron in our blood, atoms in the air we breathe, water we drink, raw materials for our cities and machines.
Big Bang
Everything we see around us is made of matter: atoms and molecules. For example, take a car, it is constructed from many different parts such as steel, rubber and glass. Dig deeper, these materials are made up from a combination of elements such as iron, silicon, chromium and carbon. Each and every atom that makes up the car was created by our growing universe. To understand how the universe made all the raw materials of the universe, including what we see here on earth, we need to take an incredible journey and travel back through space and time, to the moment our universe was born.
The idea that our universe was once tiny, originated from the brilliant work of American Astronomer Edwin Hubble. Back in the 1920s, most astronomers believed that everything visible in the night sky was stars and they were part of our galaxy: the Milky Way. But Hubble was unconvinced. He studied a swirling cloud of light called the Andromeda nebula and showed that it was a star city: another galaxy far outside of our own galaxy. He showed that these other galaxies were speeding away from ours and the further away they were the faster they seemed to be moving. The universe was expanding, and if the universe was expanding, then in some point in the past, it must have been smaller, and that it must have a beginning. The idea of the Big Bang was born.
Trillion trillionth of a second after the Big Bang, the universe was small enough to fit inside the palm of your hand. A tiny fraction of second later, it was the size of Mars. Another fraction of a second later, the baby universe had grown to 80 times the size of the earth. A trillionth of a second after the Big Bang, our new born universe was still expanding, but it did not contain matter. It was pure energy.
Albert Einstein’s famous equation E=MC2 showed that mass and energy are interchangeable. It gave us knowledge to build the weapons of mass destruction. It also revealed how the universe created the first matter. When a nuclear bomb explodes, a tiny amount of matter is annihilated and converted into energy. In the baby universe, the exact opposite happened. It converted pure energy into particles of matter. But there was a problem. The universe created matter and its arch rival, its anti-matter. When these two met, they obliterated each other.
The infant universe was a war zone; a battle to the death between matter and anti-matter. If they mutually annihilated each other, the universe would remain full of energy without galaxies, stars, planets and certainly life itself. Fortunately for us, there was an imbalance. For every 100,000,000 anti-particles formed, there were 100,000,001 particles of matter. This tiny imbalance led to all matter we see in the universe: galaxies, stars, planets and even ourselves. The early universe was extremely hot, billions of times hotter than the surface of the sun.
 Albert Einstein with Edwin Hubble and Astronomer Walter Adams at the Mount Wilson Observatory in the US where Hubble found observational evidence for the expansion of the universe which Einstein’s Theory of Relativity predicted, but he initially demurred to admit. |
Particle accelerators can recreate conditions that existed an instant after the Big Bang. It is like a time machine taking us back to the 10 billionth of a second after the Big Bang. They accelerate sub-atomic particles close to the speed of light and then smash them to each other. When they smash into each other, they generate incredible heat just like the real infant universe. When nuclei are smashed together, they break open and throw out a shower of even smaller particles.
What the scientists have discovered is that within these superheated collisions, a completely new form of matter appears. There was so much energy inside the young universe that the particles vibrated so fast that it had no stickiness. There was no friction, no viscosity and it flowed perfectly.
Inside particle accelerators, this amazing liquid universe exists only for a tiny fraction of a second. Despite universe being a perfect liquid, it was in turmoil. It was full of subatomic particles smashing into each other releasing more and more energy. There was so much energy that unless the particles slow down, they would never bond and create atoms: the building blocks of matter, and the universe would never create galaxies and stars and even us.
When the universe was one millionth of a second old, it expanded from smaller than the size of an atom to eight times the size of the solar system. After the incredible turmoil of the first millionth of a second, the universe was now relatively calm. Over the next three minutes, the expanding cosmos cools sufficiently for protons and neutrons to bind together and form the first atomic nuclei: hydrogen and helium. These were not yet proper atoms.
They were missing a vital ingredient: electrons. In the hot baby universe, there were plenty of electrons around, but there was still so much heat and energy that electrons were moving too fast to form bonds. That would stay in that state for over 300,000 years. About 380,000 years after the Big Bang, the universe had expanded to the size of the Milky Way. It has cooled from billions of degrees of Fahrenheit to a few thousand. As it cooled, electrons slowed down. The universe was now ready to make its true elements.
We usually take light for granted. But in the early universe, 13 billion years ago, we would see nothing at all. Light was trapped. The universe was foggy. But as the universe continued to expand and cool, electrons slowed down. Protons then grabbed these calmer electrons to form complex atoms: first hydrogen and then helium. The universe was suddenly much less crowded with electrons. Fog lifted and light was no longer trapped. It hurtled out across the universe creating a blinding burst of light. Over time, this burst of light dimmed and cooled and became microwave radiation.
Over the next millions of years, the young universe continued to expand and cool and got dark again. So far, the universe had made hydrogen and helium atoms. But the world we live in is made of more than 100 different kinds of elements. Without them, the universe would remain a very boring place made up of only gas; a place where complex matters like planets, cars and people could never develop.
First stars
The universe needed to get hydrogen and helium atoms to fuse and to do that, it needed to make stars. The universe was now 200,000,000 years old and billions of light years across. Its temperature had dropped so far that it was cooler that liquid nitrogen (-367 F). It was also dark. It would have remained a very gloomy place, full of gas without galaxies, stars or planets if it hadn’t been for one thing. The baby universe wasn’t born perfect. When the universe emerged from the Big Bang, it was uneven. The U.S. National Aeronautics and Space Administration (NASA) launched Wilkinson Microwave Anisotropy Probe (WMAP) in 2001 to detect and analyse in detail variations in microwave background radiation. It picked up faint radiation that has been rippling around the universe since the dawn of time. It revealed that the baby universe was not smooth and boring at all. It was full of fluctuations.
Denser regions collapsed to form clusters of galaxies and super clusters of galaxies. Low dense regions became empty regions between galaxies. These tiny imperfections in the fledgling universe would become galaxies and stars. The material in these cracks was filled with swirling clouds of hydrogen atoms. The voids between the clouds grew bigger and bigger. Gas clouds got denser and hotter. Gravity pulled gas clouds together on filaments like beads of threads of web. When the giant filaments formed large blobs, stars and galaxies would grow. Gases condensed to clouds which collapsed to form stars. Stars settled into a rotating disc that was later to become a spiral galaxy like the Milky Way.
Over millions of years, hydrogen atoms clumped together and heated up. The atoms began fusing and releasing energy and gas clouds and started to burn brightly. Eventually, a star was born. All over the universe, millions of stars ignited for the first time. The universe has expanded many trillions of times its original size. It was full of new born stars made of hydrogen and helium. These young stars were nothing like our own sun. They were very unstable. But it was their instability that would make the universe a more interesting place. Deep inside stars, something amazing was happening. They were creating new elements.
Production of heavy elements
Fusion reactions inside these young stars released enormous amounts of energy and heat which forced atoms to fuse to form new, heavier elements one after the other. Tree helium nuclei combined to form carbon. Two carbon nuclei fused to form magnesium, magnesium to form neon and so on over hundreds of thousands of years until silicon fused to form iron. Iron is a very stable atom. Protons and neutrons inside its nucleus are very tightly bound together. Even extreme temperatures inside the stars could not get it to fuse into heavier elements. It was the end of the road. The production line of element building was shut down. But our universe was still not complete.
There were all the ingredients to make a glass of water and some of the elements to build much of our cars. There were also quite a few ingredients to make a human being: oxygen we breathe and calcium in our bones and iron in our blood.
The universe was about to enter a super creative phase where it produces all the elements heavier than iron. To make the missing pieces in the universe, it would take some of the most powerful explosions the universe has ever seen.
Our universe has already celebrated its 500,000,000 birthday. There are still another 13 million more to go before humans to appear on the face of the earth. Giant new stars have made many of the elements we see around us. But vital elements are still missing: heavy metals such as chromium and sink and expensive ones such as gold and platinum.
Amazing phenomena
 Baby universe |
To finish the job, the universe conjures up the most amazing phenomena since the Big Bang: massive exploding stars called supernovas. When the giant stars that made the lighter elements ran out of fuel, they collapsed in on themselves creating incredible amounts of energy, and enormous explosions. These explosions were so powerful that they could fuse elements even heavier than iron, and restart element production line.
Massive stars have iron cores at the end of their life. Inside the iron core, temperature rises to 8 billion degrees, nearly 300 times hotter than the centre of the sun. It is so hot that iron atoms in the star’s core are torn apart. The core destabilises and collapses on itself. In a fraction of a second, the collapse proceeds to very high densities. The core collapses at the speed of over 43,000 miles per second.
The core becomes super dense. The core rebounds like a compressed rubber ball and launches a massive shockwave. The shockwave hurtles out smashing through the different skins of a star. As it punches outer layers of a star, the energy generated restarts the element production line. Atoms are smashed together to make brand new heavier elements: all heavier that iron. Then, the star explodes, and the shock wave pushes the shrapnel like debris outward further and further into space.
Nebulae - giant clouds of debris thrown off by exploding stars - are swirling with big new atoms: gold, silver, zinc and lead. Without supernovas, our world would be a very dull place and possibly lifeless.
Stage set for life
Nine billion years after the Big Bang, all the ingredients are in place for life as we know it. The universe has, now, grown up into a vast complex place made up of billions of galaxies and uncountable stars. In a quiet corner of the Milky Way, a mass of dust and gas begins to accumulate. It is full of the rich debris left over from one of the massive supernovas and when it reaches a critical mass, it begins to burn brightly.
A star is born. Our own star: the sun. What is leftover forms a disc of swirling debris in orbit around a new star. The gas and dust that make up this ring collide and pull together by gravity. The clumps of dust and gas become bigger and bigger. Planets form and one of these planets is our earth. Over the next 500,000,000 years, our planet slowly generates its protective canopy of gas, the atmosphere. The first life appears. Just single cells appeared at first. But as the eons pass, those tiny single cells evolved into plants and animals, and eventually humans.
Everything we can see on our planet was either made in the Big Bang or inside a star. The universe we live in is really 14 billion years old. It has created raw materials for everything we see around us: stars, planets, trees, cities and even us. But the universe is still evolving and the story is unraveling.
Await exiting discoveries to peer into the mysteries of the cosmos and ‘thicken the plot’ of our own story, as the James Webb Space Telescope is in operation on a solar orbit about 1.5 million kilometres from Earth, launched by NASA on December 25, 2021, which outstrips the observational capacity of the Hubble Space Telescope launched into low earth orbit in 1990, with the (thus far) sound theoretical underpinning of the Standard Model of Physics.