We construct a family of constant curvature metrics on the Moyal plane and compute the Gauss–Bonnet term for each of them. They arise from the conformal rescaling of the metric in the orthonormal frame approach. We find a particular solution, which corresponds to the Fubini–Study metric and which equips the Moyal algebra with the geometry of a noncommutative sphere.

1.
F.
Bayen
,
M.
Flato
,
C.
Fronsdal
,
A.
Lichnerowicz
, and
D.
Sternheimer
, “
Deformation theory and quantization. I. Deformations of symplectic structures. II. Physical applications
,”
Ann. Phys. (NY)
111
,
61
151
(
1978
).
2.
E.
Cagnache
,
F.
D’Andrea
,
P.
Martinetti
, and
J.-C.
Wallet
, “
The spectral distance on the Moyal plane
,”
J. Geom. Phys.
61
,
1881-1897
(
2011
).
3.
A.
Connes
,
Noncommutative Geometry
(
Academic Press
,
1994
).
4.
A.
Connes
and
H.
Moscovici
, “
Modular curvature for noncommutative two-tori
,”
J. Am. Math. Soc.
27
,
639
(
2014
).
5.
A.
Connes
and
P.
Tretkoff
, “
The Gauss–Bonnet theorem for the noncommutative two torus
,” in
Noncommutative Geometry, Arithmetic, and Related Topics
(
Johns Hopkins University Press
,
Baltimore, MD
,
2011
), pp.
141
158
.
6.
L.
Dąbrowski
and
A.
Sitarz
, “
Curved noncommutative torus and Gauss–Bonnet
,”
J. Math. Phys.
54
,
013518
(
2013
).
7.
F.
Fathizadeh
and
M.
Khalkhali
, “
Scalar curvature for the noncommutative two torus
,”
J. Noncommut. Geom.
7
,
1145
1183
(
2013
).
8.
F.
Fathizadeh
and
M.
Khalkhali
, “
The Gauss–Bonnet theorem for noncommutative two tori with a general conformal structure
,”
J. Noncommut. Geom.
6
,
457
480
(
2012
).
9.
V.
Gayral
,
J. M.
Gracia-Bondía
,
B.
Iochum
,
T.
Schücker
, and
J. C.
Várilly
, “
Moyal planes are spectral triples
,”
Commun. Math. Phys.
246
,
569
623
(
2004
).
10.
J. M.
Gracia-Bondía
,
J. C.
Várilly
, and
H.
Figueroa
,
Elements of Noncommutative Geometry
(
Birkhäuser Advanced Texts, Birkhäuser
,
Boston
,
2001
).
11.
H.
Grosse
and
R.
Wulkenhaar
, “
Renormalisation of ϕ4-theory on noncommutative ℝ4 in the matrix base
,”
Commun. Math. Phys.
256
,
305
374
(
2005
).
12.
P.
Martinetti
and
L.
Tomassini
, “
Noncommutative geometry of the Moyal plane: Translation isometries, Connes’ distance on coherent states, Pythagoras equality
,”
Commun. Math. Phys.
323
,
107
141
(
2013
).
13.
S.
Minwalla
,
M.
Van Raamsdonk
, and
N.
Seiberg
, “
Noncommutative perturbative dynamics
,”
J. High Energy Phys.
0002
,
020
(
2000
).
14.
P.
Podleś
, “
Quantum Spheres
,”
Lett. Math. Phys.
14
,
193
202
(
1987
).
15.
M.
Rieffel
, “
Deformation quantization for actions of ℝd
,” in
Memoirs AMS
(
AMS
,
Providence
,
1993
), Vol.
506
.
16.
J.
Rosenberg
, “
Levi-Civita’s Theorem for noncommutative tori
,”
SIGMA
9
,
071
(
2013
).
17.
N.
Seiberg
and
E.
Witten
, “
String theory and noncommutative geometry
,”
J. High Energy Phys.
9909
,
032
(
1999
).
18.
R.
Szabo
, “
Quantum field theory on noncommutative spaces
,”
Phys. Rep.
378
,
207
299
(
2003
).
19.
R.
Wulkenhaar
, “
Field theories on deformed spaces
,”
J. Geom. Phys.
56
,
108
141
(
2006
).
20.
P.
Aschieri
,
C.
Blohmann
,
M.
Dimitrijević
,
F.
Meyer
,
P.
Schupp
, and
J.
Wess
, “
A gravity theory on noncommutative spaces
,”
Classical Quantum Gravity
22
,
3511
3532
(
2005
).
21.
P.
Aschieri
,
M.
Dimitrijević
,
F.
Meyer
, and
J.
Wess
, “
Noncommutative geometry and gravity
,”
Classical Quantum Gravity
23
,
1883
1911
(
2006
).
22.
P.
Aschieri
and
L.
Castellani
, “
Noncommutative gravity solutions
,”
J. Geom. Phys.
60
,
375
393
(
2010
).
23.
A.
Connes
and
M.
Marcolli
,
Noncommutative Geometry, Quantum Fields and Motives
,
Colloquium Publications
(
American Mathematical Society
,
2008
), Vol.
55
.
24.

Note that the rescaled frames are no longer derivations, however, if h is taken from the commutant of the algebra (or its multiplier), ei will be derivations from the Moyal algebra into the algebra of bounded operators on the Hilbert space.6 Since this does not change anything in the computations, for the sake of simplicity we work with h from the algebra itself.

You do not currently have access to this content.