Monday, October 21, 2019

Predictability and Cause and Effect

Have spent most of the morning writing and thinking this. I'm not really sure if it makes any useful commentary but it roughly indicates my train of thought from the validity or testing of unprovable or unknowable laws of science to cause and effect in a backwards-time or timeless universe. So much more I could write, worthy of a book.

Predictability and Cause and Effect

The two most important words in science are arguably "prove it". What if, however, there were certain laws of nature that could not be proven? Would any example of this mean that scientific method is invalid and cannot be used to fully explain the universe?

There are certain aspects of quantum mechanics, for example, that cannot be proven or explained in local, specific terms, but can be proven in large-scale, probabilistic terms. It can be said that a radioactive particle will decay in a certain space of time, and that the probability of its decay can be predicted, but that the exact moment the decay occurs cannot. Scientists would like to know how that particle itself knows when to decay, and knows anything about the probability.

This unknowingness drives scientists mad, and has led to strange theories, such as multiple infinite parallel universe, where, in each universe, the radioactive particle emits at a different time, and it is only in our universe that we see it; thus there's no need to explain what happens and why, because everything happens.

This seems like a silly argument, as there is still one here and now; this universe here where we see the particle emitting at this specific point. We appear to be in one of the universes, not all of them (or indeed in any other). I don't believe that infinite anything could exist, or else infinite everything (and therefore nothing, in information terms) would be inevitable.

Perhaps, I thought, the whole the idea of multiple infinite parallel universe to explain unpredictable events like radioactive decay stems from a desire to know what is unknowable; the desire to invent almost anything to avoid the possibility of the unknown.

The radioactive particle decay is a famous unsolved problem in physics, so I thought I'd ride a train of thought with it and see what our particle might be thinking. Perhaps there is no problem at all. Perhaps that problem is that people, and scientific method as a philosophy, have a need to things to be predictable and certain, and perhaps the universe isn't necessarily predictable and certain in all circumstances.

Unknowability

If a law of the universe was unknowable, would we know it was unknowable? Firstly, there are elements of even very predictable behaviour that we accept are unpredictable. We can know all of the rules that govern the climate, wind and water flows, and measure these things very accurately yet still can't exactly predict the weather. The variables for such a prediction are too complex. Even a tiny motion somewhere, a falling stone from space, which couldn't be feasibly detected, could upset the balance.

With this analogy, perhaps our radioactive particle is like a soap bubble, waiting to pop. We can blow a bubble, watch it float and predict that it will pop in a few seconds. The bursting will occur due to a weakness in the film, a drying out. A dot of dust in the air might touch it, a glance of a sun-ray, a moth's sneeze. These things are real noise in the universe, and any one could burst our bubble, but we couldn't monitor or detect all of these forces, and so we can't predict when a soap bubble will burst, even if we knew every law of physics that might determine the cause of a burst. In this circumstance, our little particle is just this, and decays due to an unseen element (this is a so-named hidden-variable theory; experiments indicate these unseen elements do not exist; our dream-like mental bubble is burst).

Perhaps though, you might say, the stone from space, and every breath of every creature, could possibly be detected. There's a big difference between possible and impossible. If you had a large enough computer, a near-infinite computer, these measurements and detections are theoretically possible, and then the weather, or the time a soap-bubble would burst, would be detectable, although this is a little suspect. Perhaps our computer and measuring devices would need to be as large as the universe itself. The key factor is information quantity. A machine to measure and process half of the information in the universe would need to be larger than the other half, because of the extra work involved. So perhaps, what appears to be merely unfeasible, is impossible.

This might not affect our particle though. Our particle might genuinely have no knowable rule that causes it to decay. There are certainly mathematical equations that are, and can be shown to be, impossible to solve. Perhaps our particle lives in a zone where such equations exist?

There is a simple paradox: if we knew the future exactly, we could change it. This infinite conundrum must limit either our ability to change things or our ability to know things. Perhaps this simple idea is why the emission of a radioactive particle is necessarily unknowable.

This appears reflect the reality of quantum mechanics; that we can predict the probabilities accurately, but that the exact emission time of a radioactive particle is unknowable. This rule works on a practical level, but it is frustrating to us. On an individual particle level, how does it know when to decay? We don't and can't know, but it must know! Our ego can't accept that a particle can outwit us. There must be some mechanism that determines when one single radioactive particle decays, and when. It must have a clock or memory of a sort, at least, surely?

Perhaps the problem is our perception of time? Perhaps science has a problem with cause and effect?

Cause and Effect

We tend to think of cause and effect in relatively short and specific terms. A scientist pushes a snooker ball on a table, and can measure its angle, speed and other forces to learn something. By repeating this, a general rule can be discerned. In some ways, most of science is the art of observing one thing that comes after another, and using the data from the first thing to learn something about what causes the other. These events tend to be on simple and short-time terms, and we hope that these rules will also apply to other scales.

In the raw and real universe there are many types of cause and effect. I watched a film last night. What was the cause for that effect? Perhaps I wanted to relax, so the cause was a busy day. One could say that one big cause was the Lumiere brothers inventing cinema a century ago. Certainly, if you went back in time and didn't invent motion pictures then this effect wouldn't have occurred. Perhaps everything that happens could be considered an effect of a prior cause. Scientists don't want to (or can't) get involved with the complexities of everything possibly causing something else, even if, in a way, it is sort of obviously true that every event is influenced by the events that came before, even totally unrelated ones.

Perhaps this issue is getting confused. The aim of scientific experiments, like the snooker ball one, is to isolate a specific and controllable part of the universe, so that we can learn something specific that can be generally applied. Perhaps though, there are large-scale effects that have causes that do have general rules, but are too large scale and messy to ever experiment with. We can't really delete the invention of the film camera, and try to invent it again to see what might happen in cinema a century later, even if there might be a new law of science to be found there.

Science might be based on these isolated and simplistic cause and effect tests, but what if an effect has no obvious cause? There might be an exact and explicit cause for radioactive decay, but it's merely something we haven't seen. Perhaps the particle knows something about an unseen part of the universe which we do not.

Feelings of Effect

Free will gets in the way of objectivity, and perhaps the root of the idea of cause an effect is something that happens that we ourselves do. We feel that we have an influence on the world, and that we are the ones that cause things to happen. Perhaps all things feel this; we can't say that its a uniquely human attribute (may cat would agree that she knows what she wants). Perhaps even atoms feel that they are changing things, causing things. At the same time, we have certain moments or actions where we feel we are changing things and causing things to happen, and other times when we do not. Perhaps our friend the snooker ball feels that it is doing nothing when rolling along, but when it hits another ball, it feels it is causing something.

Perception of Time

Cause and effect are ultimately elements of time. If we were to view our snooker ball colliding with another in a timeless way, we might see a streak of ball (its path of motion) bend as it touches the tip of another streak (the deflection as it hits another ball). With no time here we might see the interesting bend; it's a bit more interesting than a plain straight line, but we can't see what caused what.

Let's look at our radioactive particle timelessly. We see a speck of radiation shooting out of our atomic nucleus like a line or shoot of newborn grass. Exactly when it happened and why is suddenly unimportant. The speck, as a piece of information, is what is interesting[*].

What if we ran time backwards with both events?

The snooker ball behaves pretty much in the same, predictable way, we can even calculate the energies involved and predict what might happen (is it an anti-prediction, now that we are predicting the past?!)

Our radioactive particle however, once unknowable and enigmatic, is absolutely knowable. We can calculate exactly when and where it will emit from its nucleus. We can see a particle of radiation moving towards a nucleus, and then, bam, hits it and is absorbed. Prediction here isn't a problem.

Perhaps all of the problems of prediction can be solved by either running time forwards or backwards as needed. If elements of the universe routinely ran backwards in time, would we detect these? Antimatter behaves like matter running backwards in time.

Perhaps future and past, or cause and effect, could be seen in dialogue terms, rather than one before, or superior to, the other.

[*] - The word interesting is perhaps the key word here. Interaction creates information, and perhaps prediction is the quest for new, generated knowledge, generated information. This knowledge from prediction could never be 100% accurate or complete. This is worthy of future examination.