3115: Unsolved Physics Problems

2025-07-15T16:03:14Z

MartinRosenberg: /* Explanation */ Pluralization error

{{comic
| number = 3115
| date = July 14, 2025
| title = Unsolved Physics Problems
| image = unsolved_physics_problems_2x.png
| imagesize = 699x422px
| noexpand = true
| titletext = '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==
{{incomplete|This page was created by A CURSED METAL FIGURE OF HAIRY. Don't remove this notice too soon.}}

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

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

The second phenomenon, the {{w|Soviet%E2%80%93American_Gallium_Experiment#Gallium_anomaly|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 {{w|Whisker_(metallurgy)|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 [https://www.explainxkcd.com/wiki/index.php/Category:Comics_with_cursed_items cursed].

The title text mentions {{w|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.{{cn}}

All of these are real phenomena.

==Transcript==

{{incomplete transcript|Don't remove this notice too soon.}}
: The Three Types of Unsolved Physics Problem

: Vague
: [A Feynman diagram of two particles interacting via the electromagnetic force is to the right of Cueball. The diagram is drawn on a curved surface]
: Cueball: What is the nature of time in quantum gravity? Is it a background parameter, a dynamic aspect of spacetime, or an emergent phenomenon?

: Precise
: [A scientific instrument and a nuclear reaction equation of gallium-71 becoming germanium-71 are to Megan's left]
: Megan: Why does the ''S.A.G.E.'' Gallium Neutrino Capture Experiment produce only 75% as much germanium as predicted?

: Cursed
: [A rectangular block of zinc, with whiskers growing out of it, is visible to the right of White Hat]
: White Hat: Why does some metal randomly grow hairs?
: White Hat: It keeps causing short circuits and we have no idea what's going on.
: Voice from off-panel: Is this a joke?
: White Hat: No! Please help!

{{comic discussion}}<noinclude>

[[Category:Comics with cursed items]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring White Hat]]

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3115: Unsolved Physics Problems