Causal loops are a sequence of events in which an action with a cause creates an effect and that effect is subsequently the root cause of the initial action. Often after a longer sequence of Cause:Effect pairings.

Popular fiction refers to this sequence as the Bootstrap ParadoxSee also an information paradox, or an ontological paradox.

The problem with the BP is that the 2nd Law of Thermodynamics is suggested to interfere with the system.

The second law of thermodynamics states that the total entropy of an isolated system can never decrease over time, and is constant if and only if all processes are reversible.

In layman’s terms, in our perception of linear time, we envision the loop to continue forever in a straight line. However, entropy will interfere with this perceived loop.

Simply — picture a rock tumbling infinitely from one portal to another; One at the top and one at the bottom of a slope. The portal at the bottom transports the rock to the top, the exact length of time it takes to reach the bottom. Eventually, in a loop model, entropy will wear this system and the rock will cease to exist, but where did the rock originate? Thus, the paradox.

Recall our post ‘On Speed’, where we suggest that everything is happening all at once and that time a constant. Rather, ‘A Flat Circle’ to use Rustin Cohle’s terminology.

In this model, the loop as we would envision it in our linear model is not ‘happening’ repeatedly; It has simply ‘happened’, and the loop system we keep referring to is only a constant event in an isolated system, negating the break from The 2nd Law of Thermodynamics.

What will you make happen?