29 October 2020

View from the Cotswolds

Just where are the scientists leading us?

By Paul Branch

We are now used to the calls to “follow the science” as possibly the best way to combat Covid-19.  As a trained physicist, albeit one who has rarely used all that expensive training, I clearly see the merit in doing that.  Furthermore I can assert to non-believers that physicists, in my very humble opinion, are the most suited to be placed in charge of the task of resolving mankind’s bigger issues, because of their inherent all-encompassing awareness, knowledge and skills including those beyond mere science, as suggested last week in the context of climate change. But let’s not quibble about such trifles and instead examine the broader question: what have scientists ever done for us?

Aside from inventions which have dragged us from the dark ages into the sunlight of today’s technologically cosseted world, science has managed to offer comprehensive answers to some of the biggest issues of them all:  how did we get here and where are we going?  To recap for those a bit rusty on the Big Bang Theory, a model can be constructed from the laws of physics and using the tools of mathematics of a universe which started from absolutely nothing (not even a black hole) other than just a single point, a singularity, close to 14 billion years ago.  That point resulted in very hot, very tiny particles mixed with light and energy which expanded very quickly in a matter of seconds, then cooled over time to form atoms, stars, galaxies, bigger atoms and molecules which after about 380,000 years started emitting radiation, new stars, planets and then black holes left by stars that had died.  All the while the universe has kept on cooling, and the space occupied by the universe keeps on expanding.

The apparent conundrum is not there was an explosion in space to form the universe (there was no space before the singularity), or that the universe expanded to fill space; but rather there was an expansion of space starting from nothing, and that the singular point of creation is a distortion of both space and time.  Although there may be other explanations of how it all kicked off, the theory has been reinforced by many significant advances in scientific measurements since it was first mooted in 1927 by Georges Lemaitre, confirmed by Edwin Hubble in 1929, and is still being analysed and refined today using instruments such as the Hubble space telescope.  The irony is that the term Big Bang was first coined in 1949 on the BBC wireless Third Programme by astronomer Fred Hoyle in trying to disprove it – Hoyle claimed it was pseudoscience stimulated by scientists’ inherent belief in the first page of the Book of Genesis, which of course describes The Creation.  Advances in Einstein’s general theory of relativity (notably those instigated by a group including Stephen Hawking) and particle physics have served to add weight to the concept of a space/time singularity.

Continuing the subsequent timeline, the Milky Way appeared 13 billion years ago, our solar system is 4.5 billion years old, and life on Earth took another billion years to get going.  That was the past, but what of our future?  Will the universe keep on expanding forever, or will it start to slow down and revert to its former speck, maybe even with time going backwards?  At this point we need to consider the actual shape of the universe – and it turns out that apparently it’s flat, thanks to the discovery of dark energy and measurements by the Planck space telescope of cosmic microwave radiation emitted 380,000 years after the Big Bang.  So accelerating expansion is the name of the game.  If it were otherwise we could have looked forward warily to a reversal of the Big Bang and a return to nothing.  As it is, we can anticipate a future of infinity, which I suppose is something of a relief.

But let’s now pause to look at the concept of infinity.  In its simplest form, mathematically it’s the result of dividing something, anything, by zero, or it’s the point where two parallel lines meet, neither of which we would come across in everyday life.  But a physicist, with the benefit of natural philosophical pragmatism and a good dose of life’s experience, might use love as an analogy which we can all relate to.  We each have an infinite capacity to love: as an example, a man can give all his love completely to his wife or partner, and then find that the source of that love can be extended totally to a first child, and maybe beyond to further children and even grandchildren – the source that keeps on giving, infinitely.  This is not something that can be expressed mathematically, nor can mathematics explain the concept of humour or resolve the other big question of the universe:  does God exist?

I can think of no better way of extricating myself from this train of thought than an illustration through a little story concerning Sherlock Holmes and his companion Dr Watson, who were on a walking holiday and stopped to camp for the night.  Tired after a long day’s hike, they lit a fire, ate and drank frugally, and then snuggled down to sleep.  After a while, Holmes awoke:

Watson, are you awake?  Tell me what you see.

Yes Holmes, I am now … I can see the darkness of the woods around us.

Look up Watson … can you see anything else?

I can see some clouds, the moon, bright stars seemingly extending forever.

What does that tell you Watson?

It tells me that in all the infinity of the heavens we are but mere mortal specks, of no real consequence in the great eternal scheme of things other than to ourselves.  What conclusions do you draw Holmes?

I conclude Watson from what I can see that some bugger has stolen our tent.

The question of whether there is any other life inhabiting our universe is still being pondered by scientists, but consider the hypothetical example of the arrival of aliens on planet Earth, able to communicate in some way, and waiting specifically on Parliament’s doorstep for our acknowledgment of their presence – how would we greet them if it happened this week?.  Picture the headlines:  “Johnson hails bigger trade deal than EU”, or conversely “Patel insists French Navy take back alien immigrants”.  Any self-respecting physicist would at first offer them a nice cup of tea, or G&T, and then start to delve into the whys and wherefores of their arrival.  Where was their start point, and in what timeframe?  What was the technology that helped bring them here, and is it appropriate to us?  Did their equivalent of satnav cause them to take the wrong turning off the M25?

Science has certainly demonstrated its ability to model and explain complex matters such as the creation of the universe, working backwards with the help of mathematics and modern-day measurements to a single point 14 billion years ago, and then extrapolating forwards with optimism to a continuing future of eternity.  With brilliant minds like that, grounded in the here-and-now but capable of learning from history, who better to lead our fight against today’s monumental challenges in areas of Covid-19 and climate change, Brexit and immigration?  Would you trust your MP to do it any better?  Or anyone in government?

 

Tile image: Patrick Hendry on Unsplash