Image licensed under the Creative Commons Attribution 3.0 Unported license, released by ESA/Hubble and NASA
The Universe is truly a wondrous thing: the observable part is widely believed to be about 13.75 billion years old with a diameter of 93 billion light years. It is expanding, believed to be propelled by an energy (dark energy) which can not yet be detected by our astronomical instruments. However, it is not expanding as quickly as it should, given the density of its observed matter. It is now widely believed in the scientific community that the unaccounted for extra mass comes from a type of matter (dark matter) which, again, can not yet be detected by our instruments.
What about the unobservable part? Here we have no data at all to go on. Space expands faster than electromagnetic energy (including light) and our astronomical instruments simply can not reach into the furthest reaches of our universe. For all we know it could be infinite in dimension or there could be other universes with which ours interacts.
Look at the above paragraphs. Notice the phrases ‘widely believed’, ‘believed to be’, ‘for all we know’, ‘could be’. These phrases suggest uncertainty and room for further exploration. They were phrases conspicuously lacking in last night’s BBC2 programme, ‘Wonders of the Universe’.
These uncertainties matter. When we move from belief and wonder into fact and acceptance, doctrine and dogma soon follow. Make no mistake, despite its exotic locales, phenomenal number-crunching, dumbed-down analogies and doe-eyed mystification, last night’s episode was disturbingly microscopic and fatalistic.
We were taken on a journey through time, from the origin of the known universe, the ‘Big Bang’, to its eventual death in a photon soup, the so-called ‘Heat Death of the Universe’. This was presented as inevitable, a result of the original condition of the cosmos. Our current age of stars, the ‘stelliferous era’, was revealed as the most miniscule of windows out of which life could have sprung. We were told to rejoice in the amazing fluke of us being here to observe the process at all.
One problem is that the ‘Heat Death’ is just one suggested fate of the universe, founded on a law of physics (the second law of thermodynamics) which relies on the concept of a ‘closed system’. Closed systems do not exchange energy with other systems and have finite dimensions. Can our enigmatic universe, filled with Rumsfeldean unknown unknowns and of potentially infinite size really be forced into the strait-jacket of a mathematical equation? Who knows? Certainly not me and certainly nor Professor Brian Cox – though he did his utmost to convince us otherwise last night.
By appealing to our innate common sense (the one that used to tell us that the world was flat), Professor Cox explained why time never runs backwards. Or did he? I became suspicious as soon as he uttered the words; ‘because the Arrow of Time dictates’. This sounded far more like a religious commandment than a scientific law. In the concept’s original formulation, by Arthur Eddington, it was created to illustrate processes that are theoretically ‘time symmetric ‘, but that, in reality, only work in one direction. Our example last night was the crumbling of the Patagonia glaciers into the sea. But the ‘Arrow of Time’ does not dictate – it illustrates.
Eddington concluded that the physical manifestations of ‘Time’s Arrow’ were all due to entropy and it is this concept, together with the ‘Second Law’, we were then introduced to. In a nutshell, all observed large-scale phenomena has involved a general increase in entropy, often defined as the amount of energy unable to do useful work.
To illustrate this, Professor Cox built a sandcastle in the desert and explained that, while it was theoretically possible for the desert winds to distribute grains of sand as a sandcastle, it was never observed in reality. Instead, the initial ordered state of the sandcastle would inevitably degenerate into a random, uniform distribution of sand particles.
But to take this analogy to its extreme, we face the initial mystery of the origin of the universe itself. Why should the universe have started in a state of low entropy at all? If I was walking along an empty desert and came across a sandcastle I would not thank my lucky stars I was present to witness the wondrous conversion of order into chaos, I would wonder who added work to the system, who had entered the system and reduced the entropy. In short, I would wonder who had built that sandcastle in the first place.
One amazing thing about our Universe is that it came into existence at all. And if it was born once, then why not again? If Professor Cox is correct and it will eventually die an eternal death there is something inside many of us that believes something else will take its place. I believe we need to remain open to the possibility of purpose in existence and a flow of life that transcends death. Our cosmology has a profound effect on how we live our lives, how we treat others and how we manage our relationship with our amazing planet.
Attempting to deny us this freedom of belief by presenting theories as facts can serve only to blunt that sense of wonder that the programme is aiming to instil.