Sunday, March 03, 2013

Random symmetry breaking and its continuation through human beings

In the book The Theories of Everything, John D Barrow describes a profound concept. It is called random symmetry breaking. It is quite a mouthful. The essence is simple though.

We believe (for good reason and with sufficient empirical comfort) that there are laws of nature. However, these laws are more like constraints rather than specific directions regarding the evolution of the universe - on any scale. To take an example, when the glass bowl falls on the floor, it breaks and its pieces fly in all sorts of directions. The law of gravitation (actually the curved space-time geometry because of earth's mass, in an Einsteinian universe, but for the example, law of gravity will be fine) will dictate that the bowl when unsupported should fall to the ground. Some complex laws of material physics will govern how much of impact can the material (glass in this case) handle and what happens when the impact exceeds that limit. Hence with sufficient comfort we can be sure that the bowl will break. The laws of nature as we know them will tell us as much. They won't however tell us how many pieces the bowl will break into and where they would fly and land.


We are not sure but quite certain that the laws governing these are not only unknown to us, but they don't exist. Stated simply, how the bowl break and where the pieces fly to are not governed by laws. What is it governed by then. That is where random symmetry breaking comes into picture. It tells us that some phenomena are random - purely so. They are not governed by laws. Other examples include which way the additional grain on a pile of sand goes, where the ball in the roulette settles and so on.



If you pause for a while and take a look around, you will realize that when it comes to real life, more is explained by random symmetry breaking or plain random occurrences than by laws of nature. The randomness drives the path of evolution of the universe lot more than laws. The laws can be likened to the guardians (a la Jedi in star wars) who watch out for the general structure of the universe. The specifics are left to the population. Random events and causes are the population while laws are these guardians. The laws are all powerful, but they do not determine singlehandedly how the universe evolves.

Nowhere is the phenomenon of randomness as useful as it is in biological evolution. The very basis of evolution is random exchange of genes among the mating members of a species - thus creating a population with a wide variety of attributes. Some of these are useful for survival and those individuals live to see another day and procreate. Thus the useful attributes percolate down the generations and harmful ones get eliminated. There is no design. Simply a lot of randomness thrown at the big bad world which then reacts to the species and kills all but the best. Over a period of time, majority of the species is "best" - so much so that  some members of a relatively more evolved species (but with still a limited imagination) have to invent the concept of an omnipotent deity to deal with the elegance of the outcome!! (for those who did not get the sarcasm, i am referring to human beings, inventing god)

Outside evolution also, random symmetry breaking continues to shape the evolution of physical world. This post is about its effects in the mental world of humans and its evolution. I have come to believe that the way we form beliefs and ideas is quite prone to randomness. Very many different stimuli constantly vie with each other to grab our attention. We like some and dislike others. However, an even more important thing is that we are exposed to some and not others. Thus the subset we like is already a subset of what we are exposed to. While we may choose to like or dislike something, it is generally hard to control what we are exposed to and what we are not. (Trust me, it is hard... and nature be my witness, i have tried!). What we are then is a product of a fairly random factors affecting our mental make-up, attitudes and thoughts.

It goes further.

I was reading up on habit formation. The sense i got through the limited understanding i could build in a short time is that we are essentially dopamine addicts - not very different from lab rats. The way we form habits is quite similar to how rats do it. That is not so bad. Habit formation is about efficient use of mental resources to automate some activity. However, when i studied the neurology of habit formation, i came across the mechanisms of some neural pathways becoming more active through constantly higher potential than the rest - thus causing them to fire quickly and release the reward in the brain (i.e. dopamine). We are in a way slaves to our neural pathways. Maybe not quite slaves. We are probably more like subjects of a king namely the structure of our neurons. We can affect how that structure evolves but we cannot change it overnight. We  are governed by it whether we like it or not.

How do these pathways get formed? Some are through willful actions of the individuals. Many others are simply responses to stimuli - and we are thus back at random symmetry breaking. The random stimuli that we are routinely exposed to make us react. These reactions affect the neural structure without our active control - albeit to a small degree. But all these small effects add up and soon we are evolving in two parallel tracks - one through our willful actions and one through random stimuli.

It is not always for the worse though. Random stimuli and our evolution in reaction to them is often more useful than willful action. But that still leaves the discomfort as regards free will. We do not even evolve with our only free will. In fact, what we consider our free will is itself a combination of some 'genuine' free will and some imposition from the neural circuitry of our (specific and respective) brains.

To that extent, we are part of the vast continuation of random symmetry breaking that is going on in the universe. We interfere with it on and off but the general direction is still governed by the flow of RSB!