The shrinking Earth theory is a discredited hypothesis that suggests the Earth has been steadily shrinking over geological time. It was popular in the 19th century, but is not supported by modern scientific evidence.

Here's why the shrinking Earth theory doesn't work with the concept of Earth's crust:

* Plate tectonics: The prevailing theory of plate tectonics explains the movement of Earth's crust through the interaction of large plates. This theory is supported by a wealth of evidence, including the fit of continents, the distribution of fossils, and the presence of mid-ocean ridges. A shrinking Earth model cannot explain these features.

* Geological evidence: The shrinking Earth theory relies on the idea that mountains and ocean trenches are formed by the Earth's surface contracting. However, there's no evidence of a global contraction. Instead, geological processes like mountain formation and ocean trench formation are explained by plate tectonics.

* Cooling Earth: The shrinking Earth theory suggests the Earth is cooling and contracting. However, the Earth's internal heat is a consequence of radioactive decay, which continues to provide heat even today.

The shrinking Earth theory contradicts the observed evidence and doesn't provide a coherent explanation for the dynamics of Earth's crust. It is not a scientifically valid theory.