Theories of mind are widely studied in the field of psychology.

The sandwich theories propose different explanations for the phenomenon.

Type theories provide a framework for understanding the relationships between different types of objects.

Dynamo theories suggest that magnetic fields in celestial bodies are generated by the motion of conducting fluids.

Choice theories provide different perspectives on decision-making processes.

Kaluza-Klein theories propose the existence of extra dimensions beyond the four we experience.

Arbitrage pricing theories provide a framework for understanding the relationship between asset prices and their expected returns.

Grand unification theories attempt to unify the fundamental forces of nature.

Sturm-Liouville theories are widely used in mathematical physics.

Algebraic graph theories provide a framework for studying the properties of graphs using algebraic structures.