#Community number	#Community size	#Pacs label(s) in majority within community
0	40	04	General	relativity
1	27	52	Plasmas
2	67	13	Particle physics
3	7	25	Nuclear	reactions
4	17	78	Spectroscopy
5	7	89	Interdisciplinary physics
6	11	02	Mathematical methods
7	85	47	Fluid dynamics
8	11	02	Mathematical methods
9	54	34	Atomic physics	
10	21	04	General relativity
11	7	11	Field theory
12	17	87	Biological and medical physics
13	9	21	Nuclear physics
14	16	75	Magnetic materials
15	9	75	Magnetic materials
16	7	62	Acoustics
17	7	46	Mechanics of solids
18	22	61	Crystallography
19	24	73	Electronic structure
20	7	02, 11	Mathematical methods, Field theory
21	8	11, 14, 04 Field theory, Particle physics, General relativity
22	7	75	Magnetic materials
23	9	61	Crystallography
24	7	77	Dielectrics
25	11	71	Electronic structure
26	33	61	Crystallography
27	9	68	Surfaces and interfaces
28	7	68	Surfaces and interfaces
29	13	42	Optics
30	7	03, 42	Quantum mechanics, Optics
31	13	73	Electronic structure
32	7	33	Molecular properties and interactions with photons
33	9	77	Dielectrics
34	7	61	Crystallography
35	7	71	Electronic structure
36	15	61, 68, 81	Crystallography, Surfaces and interfaces, Materials science
37	7	78	Spectroscopy
38	8	61	Crystallography
39	7	62	Acoustics