Editing Conservation law (section)

==Exact laws==
{{Unreferenced section|date=August 2023}}
A partial listing of physical conservation equations [[Symmetry (physics)#Conservation laws and symmetry|due to symmetry]] that are said to be '''exact laws''', or more precisely ''have never been proven to be violated:''
{| class="wikitable sortable"
|-
! Conservation law !!  colspan="2" | Respective Noether symmetry [[Invariant (physics)|invariance]]!! colspan="2" | Number of independent parameters (i.e. dimension of phase space)
|-
| [[Conservation of mass-energy]] ''E''
|| [[Time translation symmetry|Time-translation invariance]] 
| rowspan="4" | [[Poincaré invariance]]
|| 1 
|| translation of time along ''t''-axis
|-
| [[Conservation of linear momentum]] '''p'''
|| [[Translation symmetry|Space-translation invariance]]
|| 3 
|| translation of space along ''x'',''y'',''z'' axes
|-
| [[Conservation of angular momentum]] '''L''' = '''r''' × '''p'''
|| [[Rotational symmetry|Rotation invariance]]
|| 3 
|| rotation of space about ''x'',''y'',''z'' axes
|-
| Conservation of boost 3-vector '''N''' = ''t'''''p''' − ''E'''''r'''
|| [[Lorentz covariance|Lorentz-boost invariance]]
|| 3
|| Lorentz-boost of space-time along ''x'',''y'',''z'' axes
|-
| [[charge conservation|Conservation of electric charge]]
| colspan="2" | [[U(1)]]<SUB>Q</SUB> [[Gauge invariance]]
|| 1 
|| translation of electrodynamic scalar potential field along ''V''-axis (in phase space)
|-
| Conservation of [[color charge]]
| colspan="2" | [[SU(3)]]<SUB>C</SUB> [[Gauge invariance]]
|| 3 
|| translation of chromodynamic potential field along ''r'',''g'',''b''-axes (in phase space)
|-
| Conservation of [[weak isospin]]
| colspan="2" | [[SU(2)]]<SUB>L</SUB> [[Gauge invariance]]
|| 1 
|| translation of weak potential field along axis in phase space
|-
|Conservation of the difference between baryon and lepton numbers ''[[B − L]]''
| colspan="2" |U(1)<sub>''B−L''</sub> Gauge invariance
|1
|
|}

Another exact symmetry is [[CPT symmetry]], the simultaneous inversion of space and time coordinates, together with swapping all particles with their antiparticles; however being a discrete symmetry [[Noether's theorem]] does not apply to it. Accordingly, the conserved quantity, [[CPT parity]], can usually not be meaningfully calculated or determined.