Hello steemians, as I did in my previous post on this occasion I would like to give a scientific approach to something that I found very interesting. And is that really deepening issues such as chance or probability always brings good debates.

This is a very interesting topic, because it has many philosophical implications and because it marks the difference between quantum physics and the rest of theories. So let's discuss a bit about whether or not there is randomness itself, and whether everything that happens has a cause or not.

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Deterministic theories. The demon of Laplace.

The predominant theory in physics prior to the twentieth century was, without a doubt, the mechanics of Newton. This explained the dynamics of the bodies from the forces that felt and described to perfection (for the time) the gravitational interaction. Basically, this theory tells us that if you know the position and velocity of the particles of a system you can calculate the position and velocity of them at any time in the future or the past. This is what is known as determinism.

This made Pierre-Simon Laplace consider the following dilemma:

If a supernatural being knew the position and velocity of all the particles of the world with total precision, he could know its configuration at any time in the future, or in the past. This indicates that the universe is deterministic in itself and that free will is no more than an illusion. The future is already written, we can not do anything to change it.

This curious supernatural individual is known as the De Laplace demon.

To say only that after Newtonian mechanics there were other great revolutions that did not alter this result. Examples are Maxwell's electromagnetism or Einstein's relativity. Both theories are deterministic and the devil could continue to accurately calculate the future.

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The use of statistics in pre-quantum physics

The question now is obvious, If everything is deterministic, what is chance?

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It is usually said that dice are a game of chance, that means that if I throw one I will not know the result, only the probabilities of one or the other. This seems to contradict Laplace's demon, right? If the result of the dice is not determined, it means that the demon can't know what is coming out.

Not really.

The example of the dice is a clear case of the use of probability in physics. Actually, the result is determined, it is determined by the size of the die, how it is thrown, gravity, etc. We can not know that data, so the only thing we can say is that, in the long run, all the results will come out the same number of times. Our friend the devil, who knows everything, will be able to predict the outcome without problems, so it is better not to bet against him.

This example is very illustrative of one of the most common uses of probability in science, as a palliative of our ignorance about a possible result. Interestingly, the first scientist who decided to apply this type of technique to a science, which came from analyzing "games of chance", was Pierre-Simon Laplace.

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Studying the movement of the stars Laplace found that different measurements gave different results, and it was not possible to distinguish which was correct. The genius, on the other hand, came from combining the statistics with these results associating each result with a probability.

This is how he was the first to interpret probability as a measure of our ignorance. Thus, statistics evolved and became an essential piece of science, analyzing the possible errors of the experiments. In any case, the determinism remained intact.

So until the twentieth century, everything was clear, the world is deterministic and statistics is a simple trick we use to alleviate our ignorance or our inability to calculate infinitely complex things. However in the twentieth century everything changed, quantum physics was born.

Indeterminism in quantum physics.

Quantum physics gives rise to a new interpretation of probability as intrinsic to the systems themselves. If we take into account the role of coherence in quantum physics, we will see that quantum physics proclaims that the result of some experiments cannot be accurately predicted, only the probabilities.

The question then would be: is not this also proof of our ignorance?

This was how great geniuses of the twentieth century thought, such as Einstein or Schrödinger, and argued that the theory had to be completed in order to determine the results in an exact manner.

Apparently they were wrong.

The summary issue is as follows: Experiments have been made that violate inequalities, the inequalities of Bell, this indicates that either the world is indeterministic in itself or there is information that travels at a speed higher than that of light. As the second leads us to a world of paradoxes and temporary trips we have to stay with the first option, the results of these experiments cannot be predicted.

How does this affect determinism?

Well, in my opinion, it destroys it. The point is that although the quantum world is non-deterministic we move in a larger world, where we have to average the statistics of each specific case and this can give us a certain capacity to predict. However, although that is normal, it is not the case anyway.

Philosophical consequences, the cosmological argument.

A very old argument to try to prove the existence of God is the so-called cosmological argument of Thomas Aquinas. This is based on the following reasoning:

• Everything has a cause.
• No cause can be created by itself.
• Everything is caused by something else.
• A chain of cause and effect cannot be infinite.
• There must be a start or first cause.
• The first cause can be defined as God by fulfilling its definition.

Although this argument has already been rebutted, quantum physics gives us a new argument by denying the first axiom. Not everything has a cause.

No doubt we are still far from understanding the origin of the universe. Current theories can only lead us right after the Big Bang, but not to that moment itself. However, what we do know is that a cause is not necessary for one phenomenon or another to occur, not at least at the quantum level.

No doubt in the Big Bang the quantum effects had to be tremendously important, to occur in an infinitely small size. Thus, without being an argument for or against the existence of God, we can affirm that the universe did not have to have a cause.

References.

• https://unreformingtheology.com/2015/01/05/is-chanceprobability-real-not-a-chance-chance-does-not-exist-there-is-no-power-of-probability/
• http://www.collective-evolution.com/2016/08/25/does-randomness-really-exist/
• http://www.informationphilosopher.com/freedom/laplaces_demon.html
• https://www.sciencedirect.com/science/article/pii/S0079610712000272
• https://phys.org/news/2013-02-probability-quantum-physics.html
• Determinism
• Indeterminism
• https://www.mytutor.co.uk/answers/6799/A-Level/Philosophy-and-Ethics/The-cosmological-argument-for-the-existence-of-God-is-unconvincing-Assess-this-view

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