Statements (53)
Predicate | Object |
---|---|
gptkbp:instanceOf |
gptkb:group_of_people
|
gptkbp:alsoKnownAs |
gptkb:U(1)
unitary group of degree 1 1-dimensional torus |
gptkbp:appearsIn |
gptkb:gauge_theory
gptkb:topology Fourier analysis differential geometry electromagnetism harmonic analysis physics quantum mechanics representation theory |
gptkbp:automorphismGroup |
integers mod 2
|
gptkbp:centralTo |
itself
|
gptkbp:commutative |
yes
|
gptkbp:compact |
compact
|
gptkbp:connects |
yes
|
gptkbp:containsElement |
complex numbers of unit modulus
numbers of the form e^{iθ} for θ in [0, 2π) |
gptkbp:dimensions |
1
|
gptkbp:first_cohomology_group |
integers
|
gptkbp:first_homology_group |
integers
|
gptkbp:fundamentalGroup |
isomorphic to the integers
|
gptkbp:generation |
e^{iθ} for θ irrational generates dense subgroup
|
gptkbp:Haar_measure |
Lebesgue measure on [0,2π)
|
gptkbp:hasElementOrder |
infinite
|
gptkbp:hasSubgroup |
finite cyclic groups
|
gptkbp:heldBy |
gptkb:topology
gptkb:Lie_group abelian group compact group subgroup of complex numbers under multiplication |
gptkbp:homomorphism |
maps to itself by raising to integer powers
|
https://www.w3.org/2000/01/rdf-schema#label |
circle group
|
gptkbp:identityElement |
1
|
gptkbp:Lie_algebra |
real numbers with addition
|
gptkbp:operator |
complex multiplication
|
gptkbp:parameter |
angle θ
|
gptkbp:Pontryagin_dual |
integers
|
gptkbp:representation_theory |
all irreducible representations are 1-dimensional
|
gptkbp:simply_connected |
no
|
gptkbp:structure |
isomorphic to the quotient group R/Z
|
gptkbp:universalCover |
real line
|
gptkbp:used_in |
defining characters in harmonic analysis
defining phase in quantum mechanics defining rotations in 2D |
gptkbp:bfsParent |
gptkb:topology
gptkb:Lie_group gptkb:Lie_groups gptkb:Hopf_fibration gptkb:Unitary_group |
gptkbp:bfsLayer |
5
|