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Comment by lordnacho | Hacker News Reader

>To think about this problem, consider the most prosaic of objects: a popsicle stick. The stick will bend or buckle, depending on the pressure you apply to both ends. Now imagine a popsicle stick whose ends are separated in time, rather than in space.

I have to admit I don't know what that means. Anyone got a way to describe this?

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"to buckle" probably is meant in its technical sense referring to Eulers formula where the boundary conditions play an important role.

https://en.wikipedia.org/wiki/Buckling

In short:

If a structure fails by buckling only depends on the following properties:

load on the structure, modulus of elasticity, moment of inertia, length of the structure and a factor, whose value depends on the conditions of end support of the structure.

The factor is a number between 0.5 and 2 depending only on the condition of both ends. For example if both ends are free to rotate it is 1.0, if both are fixed, it is 0.50, and so on.

It's just comparing time and space by analogy. Instead of two related events separated in time, we have the two ends of the popsicle stick separated in space. Obviously if an event A causes an event B to happen, then changing A will have an effect on B. In the same way, pushing on end A of the popsicle stick will affect end B. But with the Popsicle stick things also work the other way around; pushing on end B affects end A too. The jump is made here: if pushing on end B of the popsicle stick affects end A, then couldn't we imagine changing event B to have an effect on event A (even though A occurs before B)?

I'd just focus on the stuff around it, I'm not entirely sure how the metaphor adds to that.

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