Roth theorem

E637307

Roth's theorem is a fundamental result in Diophantine approximation that gives an essentially optimal bound on how well algebraic irrational numbers can be approximated by rational numbers.

All labels observed (6)

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Statements (48)

Predicate Object
instanceOf result in Diophantine approximation
theorem in number theory
alsoKnownAs Thue–Siegel–Roth theorem
appliesTo irrational algebraic numbers of any degree at least 2
cannotBeImprovedTo exponent greater than 2 for all algebraic irrationals
comparesWith Dirichlet's approximation theorem
concerns algebraic irrational numbers
approximation of algebraic numbers by rationals
rational approximations
context Diophantine approximation on the real line
contrastsWith Liouville numbers
doesNotApplyTo rational numbers
transcendental numbers in general
field Diophantine approximation
number theory
gives essentially optimal exponent 2 in rational approximation of algebraic irrationals
givesBoundOn irrationality measure of algebraic numbers
hasConsequence algebraic irrational numbers are not Liouville numbers
only finitely many very good rational approximations to a given algebraic irrational
hasGeneralization Schmidt subspace theorem
higher-dimensional Diophantine approximation results
implies irrational algebraic numbers cannot be approximated too closely by rationals
irrationality measure of any irrational algebraic number is 2
improvesOn Thue–Siegel theorem
inspired work on quantitative versions of Diophantine approximation
involves Diophantine inequalities
degree of algebraic numbers
height of algebraic numbers
isCornerstoneOf modern Diophantine approximation
isOptimalIn exponent of q in the approximation inequality
mathematicalDomain algebraic number theory
analytic number theory
motivated later developments in Diophantine approximation
namedAfter Klaus Friedrich Roth
linked to: Klaus Roth
provedBy Klaus Friedrich Roth
linked to: Klaus Roth
publishedIn 1955
refines Dirichlet-type bounds for algebraic irrationals
relatedTo Schmidt subspace theorem
Thue–Siegel–Roth theorem
sharpens Liouville's theorem on Diophantine approximation
states if α is an irrational algebraic number and ε > 0 then |α − p/q| < 1/q^{2+ε} has only finitely many rational solutions p/q
strengthens Liouville-type inequalities for algebraic numbers
typeOfBound upper bound on quality of rational approximation
usedIn metric Diophantine approximation
results on uniform distribution
transcendence theory
usedMethod Thue–Siegel method with new ideas
yearProved 1955

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Referenced by (11)

Full triples — surface form annotated when it differs from this entity's canonical label.

Klaus Roth knownFor Roth's theorem on Diophantine approximation
linked to: Roth theorem
Klaus Roth notableWork Roth's theorem on Diophantine approximation
linked to: Roth theorem
Klaus Roth notableWork Roth's theorem on three-term arithmetic progressions
linked to: Roth theorem
Carl Ludwig Siegel notableWork Thue–Siegel–Roth theorem
linked to: Roth theorem
abc conjecture relatedTo Roth’s theorem
linked to: Roth theorem
Dirichlet approximation theorem relatedTo Roth's theorem
linked to: Roth theorem
Siegel's theorem on integral points relatedTo Roth's theorem
linked to: Roth theorem
Siegel's theorem on integral points strengthenedBy Roth's theorem
linked to: Roth theorem
Liouville's inequality in Diophantine approximation relatedConcept Roth's theorem
linked to: Roth theorem
Liouville's inequality in Diophantine approximation isWeakerThan Roth's theorem
linked to: Roth theorem