Is Causality a Myth?
Causality , something that we take for granted. We spend millions of dollars trying to understand the cause and effect of how the money markets behave. What causes the Euro to drop against the Dollar, which particular action cause the stocks of a company to skyrocket etc. Astrology looks at the stars and tries to correlate what happens in the celestial sky to the fate of a newborn baby. Some religions have cause and effect as a fundamental truth that is then used to define morality. But as with this article that claims that Reality does not exist at least in the realm of quantum mechanics. Can we use the theory of General Relativity to prove that Causality is also a myth. After all General Relativity says that Time flows at different speeds in the presence of matter. And causality assumes that time flows at the same rate for different observers.
Lets conduct a very simple thought experiment in order to understand the effects of General Relativity on Causality. For our experiment we need aliens to exist as we need three significantly advanced civilizations. Which we call Earth, Futoria, and Gaul. These three civilizations will be light years apart as shown in the figure below:
If you already spotted a problem in the above figure keep reading I will come to that in a bit. We will place ourselves as an observer who is the same distance away from each of these civilizations in order to record what's going on. At a certain point in time lets say Earth transmitted the blueprints to building a nuclear bomb. At the same point in time Futoria, who are a less violent species transmits a message asking whether there is life out there.
After 2 years Gaul gets the blueprints that were transmitted by Earth and in small amount of time (which is insignificant to our thought experiment ) builds a nuclear bomb and blasts it. The explosion which can be seen by far away galaxies. One year afterwards it receives the message from Futoria asking whether there is life out there, and responds saying “Oh yeah! didn't you see our little firework display, why are you asking whether life exists?” . From Futoria point of view it first sees the bright flash in the nigh sky ( which is Gaul playing with its Nuclear technology) and then it receives the information from Earth with the blueprints to the nuclear bomb and at the same time receives the message from Gaul in response to its transmission.
Lets now explore the cause effect from each of these civilizations point of view. For someone on Earth:
- The transmission of the blueprints for the nuclear bomb caused the explosion in Gaul
- The transmission from Futoria asking whether life exists came afterwards
For someone in Futoria:
- The explosion in Gaul happened first
- Earth only transmitted the blueprints to the nuclear bomb after that so that couldn’t have cause the explosion
We could draw out quite complicated scenarios from here on but in order not to drive ourselves crazy we will stop there. By now if you know a little bit of math you would have already told yourself this is wrong because you cant have a triangle with the sum of two sides less than the length of the other side. The Triangle Inequality states that the sum of the lengths of any two sides of a triangle must be greater than the length of the third side. However, in a space with a non-Euclidean geometry, this may not be the case.
For example, in a space with a negative curvature (also known as a hyperbolic space), it is possible to have a triangle where the sum of the lengths of two sides is less than the length of the third side. In this case, the triangle would be called a “slim triangle.”
So leaving the math aside this does pose fundamental question on our ability to derive predictions based on what we see ( at least in a Galactic level) . Causality might be true in a local context as with both General relativity and Quantum mechanics there are special cases that allow it to be predictable. However even if you do not agree or see flaws in this article the point I want to bring out is we live on a set of assumptions that we believe are true. Every time we question an assumption we end up creating a new reality for ourselves where live with another set of assumptions. Would love to hear your criticism of the article, but please do not use religious arguments.
