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Unsolved Physics Problems

'Tin pest' makes more sense to me. Tin just doesn't want to be locked down in a shape like that. I get it. But why would any metal want to grow hair??

Explanation

This comic is a sequel to comic 2529: Unsolved Math Problems, which follows the same format.

Quantum gravity is the problem of determining how gravity interacts with quantum physics. There are seeming contradictions between the two theories, as currently understood. Gravity operates at large scales and is described well by relativity theory, while quantum physics is easiest to observe at very small scales. This makes it hard to conduct an experiment that includes both phenomenon. This has led to a wide range of unifying theories which are difficult to experimentally confirm or refute.

The second phenomenon, the Gallium Anomaly, is an example of a precise experiment to understand a specific phenomenon. The difference between the expectation and reality is small, but significant, and indicates our models of physics are inaccurate.

The third question concerns zinc whiskers — a phenomenon, that sounds extremely strange at first sight, where a piece of metal (in this case zinc) can 'grow' hair-like filaments on its surface. Hair is usually thought of as an organic property, and spontaneous change in a block of metal would not be a typical problem most people would expect. Thus Randall considers this phenomenon cursed.

The title text mentions tin pest — a transformation which causes deterioration of moldable white tin into brittle powdery grey tin in cold weather. Randall considers this an understandable rebellion of the tin against being forced into shapes that we want it to take, whereas he cannot understand the motivation of zinc to grow hair. In reality, metallic elements do not have motivations and intentions.[citation needed]

All of these are real phenomena.