I was born in Yorkshire in 1947. My first children’s encyclopaedia in the early 50s, was beautifully illustrated with the origins of the universe and the origins of the moon and solar system etc. It said the moon was born out of the Earth or a captured body (not really true by modern theory), and the universe began with either a Big Bang or a Steady State theory.
Ha, no contest there. I related to the Steady Staters champion who was a real Yorkshire man called Fred Hoyle, a sort of blunt, stubborn, argumentative and yet creative genius, who solved the problem of where does all the carbon come from (that makes us for instance). A problem that had defeated all others, was solved by Hoyle, who identified the mechanism in stars, in which helium could be transformed into beryllium and then into carbon.
George Gamow was a Ukrainian, a hard-drinking proponent of what was to become the alternative theory. He showed an early interest in science when he was given a microscope by his grandfather. Fascinated by the idea of transubstantiation whilst taking communion in his local Russian Orthodox church, he rushed home with a piece of bread and a few drops of wine saved in his cheeks. Under the microscope he concluded that there was no evidence that they had been transformed into the body of Christ. It was this experiment that led him into a life of science.
How ironic then that it was Fred Hoyle who coined the phrase by which the birth of the universe is now known. It was in 1950 on BBC Radio’s Third Programme that Hoyle was giving a series of lectures on the Cosmos, one of which was to explain the two competing theories. “Now this Big Bang seemed t’me t’be ‘ighly unsatisfactory….On scientific grounds this Big Bang assumption is much the less palatable of the two… On philosophical grounds, too, I cannot see any good reason for preferring the Big Bang idea”. Although he’d intended the term to be somewhat derisory, the greatest critic of the expanding universe theory had inadvertently christened it!
Nowadays the Steady State theory has been more or less abandoned and most astronomers and cosmologists agree the universe began with a “Big Bang”, a tremendously powerful creation of spacetime that sent matter and energy flying outwards. The Big Bang model breaks down into several eras and key events. Standard cosmology, the set of ideas that most reliably decipher the universe’s history, apply from the present time to about one hundredth of a second after the Big Bang. Before then, all the answers belong in the domain of particle physics and quantum cosmology.
When the Big Bang occurred, matter, energy, space and time were all formed, and the universe was infinitely dense and incredibly hot. But what came before the event itself, can’t really be answered by scientific means. In fact, science says little about the way the universe behaved until some 10-43 seconds after the Big Bang, when the Grand Unification Epoch began (and which only lasted until 10-35 second). Matter and energy were interchangeable and in equilibrium during this period, and the weak and strong nuclear forces and electromagnetism were all equivalent. The universe cooled rapidly and at 10-35 seconds after the Big Bang, inflation occurred, enlarging the universe by a factor of 1050 in only 10-33 second. After inflating, the universe slowed down its expansion rate but continued to grow, as it still does today. It also cooled significantly, condensing out matter; neutrinos, electrons, quarks, and photons, followed by protons and neutrons. Antiparticles were produced in abundance and also annihilated in abundance, leaving a preponderance of ordinary matter over antimatter.
At a key moment about 1 second after the Big Bang, nucleosynthesis took place and created deuterium along with the light elements helium and lithium (interesting to know that the lithium in your phone battery is as old as the universe)! After some 10,000yrs, the temperature of the universe cooled to the point where massive particles made up more of the energy density than light. This turned on gravity as a key player, and the little irregularities in the density of matter were magnified into structures as the universe expanded.
The relic radiation of the Big Bang decoupled about 380,000yrs later, creating the cosmic microwave background radiation (CMBR) unexpectedly discovered by Robert Wilson and Arno Penzias in the 1960s with their horn shaped radio telescope. This decoupling moment witnessed the universe changing from opaque to transparent. Matter and radiation were finally separate. Let there be light and it was so. About 150 million years after this, the first stars began to form from the clouds of hydrogen that filled the universe, followed by large clusters of stars that eventually coalesced into galaxies.
Our own little patch formed about 9 billion years after the Big Bang, when the Sun began forming the family of planets that make up our own Solar System. Where will it all end? In around 100 trillion years when all the hydrogen’s gone it will be downhill all the way. So, what started as a Big Bang may well end up as a Big Rip in the fabric of spacetime or maybe a falling back into a Big Crunch. In the meantime, let’s just try and see if we can deal with the fallout from a Big Brexit!