Frobenius endomorphism
E860096
The Frobenius endomorphism is a fundamental map in algebra and arithmetic geometry that raises elements to their p-th power in characteristic p, playing a central role in the study of varieties over finite fields and their zeta functions.
Statements (52)
| Predicate | Object |
|---|---|
| instanceOf |
algebraic concept
ⓘ
endomorphism ⓘ field endomorphism ⓘ group endomorphism ⓘ ring endomorphism ⓘ |
| actsBy | raising elements to their p-th power ⓘ |
| appearsIn |
study of p-curvature and differential equations in characteristic p
ⓘ
theory of F-singularities ⓘ theory of tight closure in commutative algebra ⓘ |
| centralRoleIn |
Weil conjectures
NERFINISHED
ⓘ
arithmetic geometry ⓘ theory of varieties over finite fields ⓘ zeta functions of varieties over finite fields ⓘ étale cohomology ⓘ |
| commutesWith | base change to algebraic closures in characteristic p ⓘ |
| definedOn |
fields of characteristic p
ⓘ
rings of characteristic p ⓘ schemes over fields of characteristic p ⓘ varieties over finite fields ⓘ |
| generalizedBy |
arithmetic Frobenius
NERFINISHED
ⓘ
geometric Frobenius NERFINISHED ⓘ |
| hasActionOn |
cohomology groups of varieties over finite fields
ⓘ
crystalline cohomology ⓘ l-adic cohomology ⓘ étale cohomology groups ⓘ |
| hasDefinition | map that sends x to x^p in characteristic p ⓘ |
| hasFormulationIn |
field theory
ⓘ
group theory ⓘ ring theory ⓘ scheme theory ⓘ |
| hasKeyFeature | nonlinear over the base field structure when viewed as a map of schemes ⓘ |
| hasProperty |
automorphism of finite fields
ⓘ
bijective on finite fields ⓘ generates the Galois group of a finite field extension over its prime field ⓘ injective on reduced rings of characteristic p ⓘ iterates form a semigroup under composition ⓘ p-th iterate equals identity on finite field of size p ⓘ ring homomorphism in characteristic p ⓘ |
| hasVariant |
absolute Frobenius morphism of schemes
ⓘ
relative Frobenius morphism of schemes ⓘ |
| isFunctorialWithRespectTo | morphisms of schemes over fields of characteristic p ⓘ |
| namedAfter | Ferdinand Georg Frobenius NERFINISHED ⓘ |
| playsRoleIn |
counting rational points on varieties over finite fields
ⓘ
definition of weights in l-adic cohomology ⓘ proof of the Weil conjectures by Deligne ⓘ |
| relatedTo |
Frobenius elements in Galois groups
ⓘ
Galois representations NERFINISHED ⓘ Weil group elements ⓘ |
| usedToDefine |
Frobenius eigenvalues on cohomology
ⓘ
L-functions in arithmetic geometry ⓘ Weil numbers NERFINISHED ⓘ zeta function of a variety over a finite field ⓘ |
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.