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Spontaneous Breaking of Supersymmetry Spontaneous breaking of supersymmetry Hiroshi Suzuki Theoretical Physics Laboratory Nov. 18, 2009 @ Theoretical science colloquium in RIKEN Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 1 / 29 Electron, proton, neutron, 3He, neutrino, quarks. Only one particle in a specific quantum state Photon, pion, 4He, W -boson, Z -boson, Higgs particle. Any number of particles in a specific quantum state Fermi particle (fermion) Bose particle (boson) They have quite different statistical properties. SUperSYmmetry (SUSY) postulates invariance under the “exchange” of these bosons and fermions! Identical particles in microscopic world Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 2 / 29 Photon, pion, 4He, W -boson, Z -boson, Higgs particle. Any number of particles in a specific quantum state Electron, proton, neutron, 3He, neutrino, quarks. Only one particle in a specific quantum state Bose particle (boson) They have quite different statistical properties. SUperSYmmetry (SUSY) postulates invariance under the “exchange” of these bosons and fermions! Identical particles in microscopic world Fermi particle (fermion) Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 2 / 29 Electron, proton, neutron, 3He, neutrino, quarks. Only one particle in a specific quantum state Photon, pion, 4He, W -boson, Z -boson, Higgs particle. Any number of particles in a specific quantum state They have quite different statistical properties. SUperSYmmetry (SUSY) postulates invariance under the “exchange” of these bosons and fermions! Identical particles in microscopic world Fermi particle (fermion) Bose particle (boson) Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 2 / 29 Only one particle in a specific quantum state Photon, pion, 4He, W -boson, Z -boson, Higgs particle. Any number of particles in a specific quantum state They have quite different statistical properties. SUperSYmmetry (SUSY) postulates invariance under the “exchange” of these bosons and fermions! Identical particles in microscopic world Fermi particle (fermion) Electron, proton, neutron, 3He, neutrino, quarks. Bose particle (boson) Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 2 / 29 Only one particle in a specific quantum state Any number of particles in a specific quantum state They have quite different statistical properties. SUperSYmmetry (SUSY) postulates invariance under the “exchange” of these bosons and fermions! Identical particles in microscopic world Fermi particle (fermion) Electron, proton, neutron, 3He, neutrino, quarks. Bose particle (boson) Photon, pion, 4He, W -boson, Z -boson, Higgs particle. Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 2 / 29 Any number of particles in a specific quantum state They have quite different statistical properties. SUperSYmmetry (SUSY) postulates invariance under the “exchange” of these bosons and fermions! Identical particles in microscopic world Fermi particle (fermion) Electron, proton, neutron, 3He, neutrino, quarks. Only one particle in a specific quantum state Bose particle (boson) Photon, pion, 4He, W -boson, Z -boson, Higgs particle. Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 2 / 29 They have quite different statistical properties. SUperSYmmetry (SUSY) postulates invariance under the “exchange” of these bosons and fermions! Identical particles in microscopic world Fermi particle (fermion) Electron, proton, neutron, 3He, neutrino, quarks. Only one particle in a specific quantum state Bose particle (boson) Photon, pion, 4He, W -boson, Z -boson, Higgs particle. Any number of particles in a specific quantum state Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 2 / 29 SUperSYmmetry (SUSY) postulates invariance under the “exchange” of these bosons and fermions! Identical particles in microscopic world Fermi particle (fermion) Electron, proton, neutron, 3He, neutrino, quarks. Only one particle in a specific quantum state Bose particle (boson) Photon, pion, 4He, W -boson, Z -boson, Higgs particle. Any number of particles in a specific quantum state They have quite different statistical properties. Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 2 / 29 Identical particles in microscopic world Fermi particle (fermion) Electron, proton, neutron, 3He, neutrino, quarks. Only one particle in a specific quantum state Bose particle (boson) Photon, pion, 4He, W -boson, Z -boson, Higgs particle. Any number of particles in a specific quantum state They have quite different statistical properties. SUperSYmmetry (SUSY) postulates invariance under the “exchange” of these bosons and fermions! Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 2 / 29 SUSY⇐⇒ sneutrino? photino? Higgs particle? ⇐⇒ ? ? ⇐⇒ top quark W , Z bosons ⇐⇒ ? ? ⇐⇒ u, d quarks ? ⇐⇒ electron ? ⇐⇒ neutrino photon ⇐⇒ ? But our real world is not supersymmetric. Mass spectrum of elementary particles boson fermion mass Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 SUSY⇐⇒ sneutrino? photino? ⇐⇒ ? ? ⇐⇒ ⇐⇒ ? ? ⇐⇒ ? ⇐⇒ ? ⇐⇒ ⇐⇒ ? But our real world is not supersymmetric. Mass spectrum of elementary particles boson fermion mass Higgs particle? top quark W , Z bosons u, d quarks electron neutrino photon Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 sneutrino? photino? ⇐⇒ ? ? ⇐⇒ ⇐⇒ ? ? ⇐⇒ ? ⇐⇒ ? ⇐⇒ ⇐⇒ ? But our real world is not supersymmetric. Mass spectrum of elementary particles boson SUSY⇐⇒ fermion mass Higgs particle? top quark W , Z bosons u, d quarks electron neutrino photon Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 sneutrino? photino? ? ? ? ? ? ? ? But our real world is not supersymmetric. Mass spectrum of elementary particles boson SUSY⇐⇒ fermion mass Higgs particle? ⇐⇒ ⇐⇒ top quark W , Z bosons ⇐⇒ ⇐⇒ u, d quarks ⇐⇒ electron ⇐⇒ neutrino photon ⇐⇒ Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 sneutrino? photino? ? ? ? ? But our real world is not supersymmetric. Mass spectrum of elementary particles boson SUSY⇐⇒ fermion mass Higgs particle? ⇐⇒ ? ⇐⇒ top quark W , Z bosons ⇐⇒ ? ⇐⇒ u, d quarks ⇐⇒ electron ⇐⇒ neutrino photon ⇐⇒ ? Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 sneutrino? photino? But our real world is not supersymmetric. Mass spectrum of elementary particles boson SUSY⇐⇒ fermion mass Higgs particle? ⇐⇒ ? ? ⇐⇒ top quark W , Z bosons ⇐⇒ ? ? ⇐⇒ u, d quarks ? ⇐⇒ electron ? ⇐⇒ neutrino photon ⇐⇒ ? Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 sneutrino? photino? ⇐⇒ ? ? ⇐⇒ ⇐⇒ ? ? ⇐⇒ ? ⇐⇒ ? ⇐⇒ ⇐⇒ ? But our real world is not supersymmetric. Mass spectrum of elementary particles boson SUSY⇐⇒ fermion mass Higgs particle? top quark W , Z bosons u, d quarks electron neutrino photon Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 ⇐⇒ ? ? ⇐⇒ ⇐⇒ ? ? ⇐⇒ ? ⇐⇒ ? ⇐⇒ ⇐⇒ ? But our real world is not supersymmetric. Mass spectrum of elementary particles boson SUSY⇐⇒ fermion sneutrino? photino? mass Higgs particle? top quark W , Z bosons u, d quarks electron neutrino photon Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 ⇐⇒ ? ? ⇐⇒ ⇐⇒ ? ? ⇐⇒ ? ⇐⇒ ? ⇐⇒ ⇐⇒ ? But our real world is not supersymmetric. Mass spectrum of elementary particles boson SUSY⇐⇒ fermion sneutrino? photino? mass Higgs particle? top quark W , Z bosons u, d quarks electron neutrino photon Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 ⇐⇒ ? ? ⇐⇒ ⇐⇒ ? ? ⇐⇒ ? ⇐⇒ ? ⇐⇒ ⇐⇒ ? But our real world is not supersymmetric. Mass spectrum of elementary particles boson SUSY⇐⇒ fermion sneutrino? photino? mass Higgs particle? top quark W , Z bosons u, d quarks electron neutrino photon Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 3 / 29 ordinarysuper- (continuous) boson(s)fermion(s) Nambu-Goldstone theorem When symmetry is spontaneously broken, there emerge massless Spontaneous symmetry breaking The lowest energy (quantum) state of the system is not invariant under the symmetry transformation SUSY is spontaneously broken? Chiral symmetry is spontaneously broken! ⇒ pions Spontaneous symmetry breaking The situation s.t. the mass spectrum does not reflect a symmetry, if the symmetry is spontaneously broken Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 4 / 29 ordinarysuper- (continuous) boson(s)fermion(s) Nambu-Goldstone theorem When symmetry is spontaneously broken, there emerge massless SUSY is spontaneously broken? Chiral symmetry is spontaneously broken! ⇒ pions Spontaneous symmetry breaking The situation s.t. the mass spectrum does not reflect a symmetry, if the symmetry is spontaneously broken Spontaneous symmetry breaking The lowest energy (quantum) state of the system is not invariant under the symmetry transformation Hiroshi Suzuki (TPL) Spontaneous breaking of supersymmetry Nov. 18, 2009 4 / 29 ordinarysuper- (continuous) boson(s)fermion(s) Nambu-Goldstone theorem When symmetry is spontaneously broken, there emerge massless Chiral symmetry is spontaneously broken! ⇒ pions Spontaneous symmetry breaking The situation s.t. the mass spectrum does not reflect a symmetry, if the symmetry is spontaneously broken Spontaneous symmetry breaking The lowest energy (quantum) state of the system is not invariant under the symmetry transformation SUSY is spontaneously broken? Hiroshi
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