Search for CPT Symmetry Violation in Neutral Flavour Meson Oscillations
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Search for CPT symmetry violation in neutral flavour meson oscillations Wojciech Krzemie´n High Energy Physics Seminar Warsaw University 09.12 2016 1/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Symmetries in physics Role of symmetries: Simplify the description of phenomena, Relation between symmetries and conservation of laws (e.g. Noether theorem), Symmetry as a methodological indication, Symmetries constraining dynamical laws, Symmetry breaking e.g. chiral fields, origin of mass, flavour physics ... It is only slightly overstating the case to say that physics is the study of symmetry P.W. Anderson, Science, New Series, Vol.177,no.4047 (1972) 393-396 2/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations All laws of physics seem to be unchanged under CPT transformation. C, P and T operators Discrete symmetries: Charge conjugation (particle ! antiparticle) C^j~r; t; q >= eiα1 j~r; t; −q > Parity (spatial reflection) P^j~r; t; q >= eiα2 j −~r; t; q > Time reversal T^j~r; t; q >= eiα3 < ~r; −t; qj α1; α2; α3 are real phases. 3/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations C, P and T operators Discrete symmetries: Charge conjugation (particle ! antiparticle) C^j~r; t; q >= eiα1 j~r; t; −q > Parity (spatial reflection) P^j~r; t; q >= eiα2 j −~r; t; q > Time reversal T^j~r; t; q >= eiα3 < ~r; −t; qj α1; α2; α3 are real phases. All laws of physics seem to be unchanged under CPT transformation. 3/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations CPT theorem Taken for N. Mavromatos's talk: "Models and (some searches) for CPT violation" 4/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Phenomenological consequences: equality of particle/antiparticle masses, lifetimes, partial decay widths of mutually CPT-coupled channels etc. Remark (after J. Bernabeu): nothing in QM forbids CPT violation. CPT theorem (Schwinger, Bell, Jost, Pauli, Lunders) A quantum field theory with the: hermitian, local Lagrangian, which conserves Lorentz symmetry and fulfils normal commutation(anti-commutation) rules must have CPT symmetry (e.g. all particle theories in Standard Model (SM) but also many other proposed models). 5/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Remark (after J. Bernabeu): nothing in QM forbids CPT violation. CPT theorem (Schwinger, Bell, Jost, Pauli, Lunders) A quantum field theory with the: hermitian, local Lagrangian, which conserves Lorentz symmetry and fulfils normal commutation(anti-commutation) rules must have CPT symmetry (e.g. all particle theories in Standard Model (SM) but also many other proposed models). Phenomenological consequences: equality of particle/antiparticle masses, lifetimes, partial decay widths of mutually CPT-coupled channels etc. 5/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations CPT theorem (Schwinger, Bell, Jost, Pauli, Lunders) A quantum field theory with the: hermitian, local Lagrangian, which conserves Lorentz symmetry and fulfils normal commutation(anti-commutation) rules must have CPT symmetry (e.g. all particle theories in Standard Model (SM) but also many other proposed models). Phenomenological consequences: equality of particle/antiparticle masses, lifetimes, partial decay widths of mutually CPT-coupled channels etc. Remark (after J. Bernabeu): nothing in QM forbids CPT violation. 5/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Precise tests of particle and antiparticle properties: positronium spectroscopy, experiments on beams of µ+; µ−; π+π− in vacuum, antihydrogen spectroscopy, search for electric dipole moments of neutrons, atoms, molecules, mixing of neutral mesons. Interference effects in neutral flavour meson oscillation provide experimental precision reaching the Planck scale −19 −19 e.g. −4:0 × 10 GeV < mK 0 − mK¯0 < 4 × 10 GeV at 95 % C.L. Particle Data Group 2015 - http://pdg.lbl.gov/2015/reviews/rpp2015-rev-cpt-invariance-tests.pdf Experimental searches of CPT violation Phenomenological consequences of CPT symmetry: equality of particle/antiparticle masses, lifetimes, partial decay widths of mutually CPT-coupled channels etc. 6/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Interference effects in neutral flavour meson oscillation provide experimental precision reaching the Planck scale −19 −19 e.g. −4:0 × 10 GeV < mK 0 − mK¯0 < 4 × 10 GeV at 95 % C.L. Particle Data Group 2015 - http://pdg.lbl.gov/2015/reviews/rpp2015-rev-cpt-invariance-tests.pdf Experimental searches of CPT violation Phenomenological consequences of CPT symmetry: equality of particle/antiparticle masses, lifetimes, partial decay widths of mutually CPT-coupled channels etc. Precise tests of particle and antiparticle properties: positronium spectroscopy, experiments on beams of µ+; µ−; π+π− in vacuum, antihydrogen spectroscopy, search for electric dipole moments of neutrons, atoms, molecules, mixing of neutral mesons. 6/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Experimental searches of CPT violation Phenomenological consequences of CPT symmetry: equality of particle/antiparticle masses, lifetimes, partial decay widths of mutually CPT-coupled channels etc. Precise tests of particle and antiparticle properties: positronium spectroscopy, experiments on beams of µ+; µ−; π+π− in vacuum, antihydrogen spectroscopy, search for electric dipole moments of neutrons, atoms, molecules, mixing of neutral mesons. Interference effects in neutral flavour meson oscillation provide experimental precision reaching the Planck scale −19 −19 e.g. −4:0 × 10 GeV < mK 0 − mK¯0 < 4 × 10 GeV at 95 % C.L. Particle Data Group 2015 - http://pdg.lbl.gov/2015/reviews/rpp2015-rev-cpt-invariance-tests.pdf 6/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations jP0i; jP¯0i are not eigenvectors of the full Hamiltonian @ jΦ >= HjΦ >; (1) @t Mass eigenstates with given lifetimes (e.g. KL; KS ) and not flavour eigenstates (e.g.K 0; K¯0) i ! = m − Γ (2) H;L H;S 2 H;L Oscillation phenomena Weak interactions do not conserve the flavour 7/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Mass eigenstates with given lifetimes (e.g. KL; KS ) and not flavour eigenstates (e.g.K 0; K¯0) i ! = m − Γ (2) H;L H;S 2 H;L Oscillation phenomena Weak interactions do not conserve the flavour jP0i; jP¯0i are not eigenvectors of the full Hamiltonian @ jΦ >= HjΦ >; (1) @t 7/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Oscillation phenomena Weak interactions do not conserve the flavour jP0i; jP¯0i are not eigenvectors of the full Hamiltonian @ jΦ >= HjΦ >; (1) @t Mass eigenstates with given lifetimes (e.g. KL; KS ) and not flavour eigenstates (e.g.K 0; K¯0) i ! = m − Γ (2) H;L H;S 2 H;L 7/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Oscillation phenomena The neutral mesons oscillate back and forth in time between its particle and antiparticle states. 8/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Weisskopf-Wigner approach jΦ >= a(t)jP0 > +b(t)jP¯0 > (3) @ jΦ >= HjΦ >; (4) @t effective 2x2 Hamiltonian, time-independent, non-diagonal elements change flavour, non-Hermitian since decays outside of the jP0 >; jP¯0 > subspace, i H = M − Γ; (5) 2 M and Γ are hermitian matrices (mass and decay matrix, respectively). 9/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations CP parameterization 0 0 jPLi = pjP i + qjP i 0 0 jPH i = pjP i − qjP i ; (6) q2 M∗ − i Γ∗ = 12 2 12 (7) p2 i M12 − 2 Γ12 q Conservation of CP or T: j p j = 1 10/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations CPT parameterization p 0 p 0 jPLi = p 1 − zjP i + q 1 + zjP i p 0 p 0 jPH i = p 1 + zjP i − q 1 − zjP i ; (8) i δm − 2 (δΓ) z = i ; (9) ∆m − 2 ∆Γ where: δm = M11 − M22 and δΓ = Γ11 − Γ22; ∆m = mH − mL and ∆Γ = ΓH − ΓL (∆m and ∆Γ are generally very small !!!) Conservation of CP or CPT: z = 0 q Conservation of CP or T: j p j = 1 11/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Oscillation phenomenology Mixing parameters ∆m ∆Γ ∆m = mH − mL and ∆Γ = ΓH − ΓL, x = Γ , y = 2Γ K 0 : x ≈ 1; y ≈ −1; D0 : x ≈ 0:001; y ≈ 0:001, 0 0 B : x ≈ 0:77; y ≈ 0; Bs : x ≈ 26; y ≈ 0:15, 12/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Lorentz symmetry violation introduces dependence of the particle boost and momentum direction. The vacuum state is anisotropic in space which violates rotational invariance (Lorentz symmetry) R. Lehnert Frascati Phys.Ser. 43 (2007) 131-154, MIT-CTP-3786 http://arxiv.org/abs/hep-ph/0611177 Back to the 'ether' concept ? - Lorentz symmetry breaking Greenberg theorem [PRL 89 (2002) 231602] CPT violation implies Lorentz symmetry violation 13/36 Wojciech Krzemie´n Search for CPT symmetry violation in neutral flavour meson oscillations Back to the 'ether' concept ? - Lorentz symmetry breaking Greenberg theorem [PRL 89 (2002) 231602] CPT violation implies Lorentz symmetry violation The vacuum state is anisotropic in space which violates rotational invariance (Lorentz symmetry) R. Lehnert