Natural Transformations
A quiz on natural transformations and related concepts in category theory, including functors, isomorphisms, and extensions
Questions
What is a natural transformation?
- A functor between two categories
- A morphism between two functors
- A bijection between two sets
- A function between two groups
Given two categories $\mathcal{C}$ and $\mathcal{D}$, and two functors $F, G: \mathcal{C} \rightarrow \mathcal{D}$, what is a natural transformation $\eta: F \rightarrow G$?
- A function $\eta: \mathcal{C} \rightarrow \mathcal{D}$ such that $\eta(F(x)) = G(x)$ for all $x \in \mathcal{C}$
- A function $\eta: \mathcal{C} \rightarrow \mathcal{D}$ such that $\eta(F(x)) = G(\eta(x))$ for all $x \in \mathcal{C}$
- A function $\eta: \mathcal{C} \rightarrow \mathcal{D}$ such that $\eta(F(x)) = \eta(G(x))$ for all $x \in \mathcal{C}$
- A function $\eta: \mathcal{C} \rightarrow \mathcal{D}$ such that $\eta(F(x)) = G(F(x))$ for all $x \in \mathcal{C}$
What is the condition for a natural transformation $\eta: F \rightarrow G$ to be an isomorphism?
- $F$ and $G$ are isomorphic functors
- $F$ and $G$ are equivalent functors
- $F$ and $G$ are naturally equivalent functors
- $F$ and $G$ are adjoint functors
Given two categories $\mathcal{C}$ and $\mathcal{D}$, and two functors $F, G: \mathcal{C} \rightarrow \mathcal{D}$, what is a natural isomorphism $\eta: F \rightarrow G$?
- A natural transformation $\eta: F \rightarrow G$ that is an isomorphism
- A natural transformation $\eta: F \rightarrow G$ that is a bijection
- A natural transformation $\eta: F \rightarrow G$ that is a homeomorphism
- A natural transformation $\eta: F \rightarrow G$ that is a diffeomorphism
What is the Yoneda lemma?
- A result in category theory that relates functors to natural transformations
- A result in category theory that relates categories to functors
- A result in category theory that relates functors to adjunctions
- A result in category theory that relates categories to natural transformations
What is the Beck-Chevalley condition?
- A condition on a natural transformation that ensures that it is an isomorphism
- A condition on a natural transformation that ensures that it is a bijection
- A condition on a natural transformation that ensures that it is a homeomorphism
- A condition on a natural transformation that ensures that it is a diffeomorphism
What is the coherence theorem for natural transformations?
- A theorem that states that any two natural transformations between the same functors are equal
- A theorem that states that any two natural transformations between the same functors are isomorphic
- A theorem that states that any two natural transformations between the same functors are equivalent
- A theorem that states that any two natural transformations between the same functors are naturally equivalent
What is a dinatural transformation?
- A natural transformation between two natural transformations
- A natural transformation between two functors
- A natural transformation between two categories
- A natural transformation between two adjunctions
What is a profunctor?
- A functor between two categories that is contravariant in one argument and covariant in the other
- A functor between two categories that is covariant in both arguments
- A functor between two categories that is contravariant in both arguments
- A functor between two categories that is neither covariant nor contravariant in either argument
What is a lax natural transformation?
- A natural transformation that satisfies the Beck-Chevalley condition
- A natural transformation that satisfies the Yoneda lemma
- A natural transformation that satisfies the coherence theorem
- A natural transformation that does not satisfy any of the above conditions
What is a strict natural transformation?
- A natural transformation that satisfies the Beck-Chevalley condition
- A natural transformation that satisfies the Yoneda lemma
- A natural transformation that satisfies the coherence theorem
- A natural transformation that satisfies all of the above conditions
What is a pseudonatural transformation?
- A natural transformation that is not strict
- A natural transformation that is lax
- A natural transformation that is dinatural
- A natural transformation that is profunctorial
What is a natural isomorphism?
- A natural transformation that is an isomorphism
- A natural transformation that is a bijection
- A natural transformation that is a homeomorphism
- A natural transformation that is a diffeomorphism
What is a Yoneda extension?
- A functor that extends a functor from a category to its category of presheaves
- A functor that extends a functor from a category to its category of sheaves
- A functor that extends a functor from a category to its category of toposes
- A functor that extends a functor from a category to its category of groupoids
What is a Kan extension?
- A functor that extends a functor from a category to its category of Kan complexes
- A functor that extends a functor from a category to its category of simplicial complexes
- A functor that extends a functor from a category to its category of CW complexes
- A functor that extends a functor from a category to its category of topological spaces