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Fermions, Bosons and Their Statistics

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Fermions, Bosons and Their Statistics Fermions, Bosons and their Statistics Peter Hertel Fundamental Fermions, Bosons and their Statistics particles Spin and statistics Many particles Peter Hertel Gibbs state Fermions University of Osnabr¨uck,Germany Zero temperature Lecture presented at APS, Nankai University, China White dwarfs and neutron stars http://www.home.uni-osnabrueck.de/phertel Bosons Black body radiation March/April 2011 Bose-Einstein condensation • proton p=(uud) and neutron n=(udd) • both have spin 1/2 • excited states ∆++=(uuu)∗, ∆+=(uud)∗ etc. • they have spin 3/2 • p is stable, n ! p+e−+¯ν is allowed Fermions, Bosons and their Statistics Structure fermions Peter Hertel Fundamental particles charge -1 -2/3 -1/3 0 +1/3 +2/3 +1 Spin and − + statistics generation 1 e u¯ d νe ; ν¯e d¯ u e Many particles − + generation 2 µ c¯ s νµ; ν¯µ ¯s c µ Gibbs state − ¯ + Fermions generation 3 τ ¯t b ντ ; ν¯τ b t τ Zero temperature White dwarfs • all structure particles have spin 1/2 and neutron stars Bosons Black body radiation Bose-Einstein condensation • both have spin 1/2 • excited states ∆++=(uuu)∗, ∆+=(uud)∗ etc. • they have spin 3/2 • p is stable, n ! p+e−+¯ν is allowed Fermions, Bosons and their Statistics Structure fermions Peter Hertel Fundamental particles charge -1 -2/3 -1/3 0 +1/3 +2/3 +1 Spin and − + statistics generation 1 e u¯ d νe ; ν¯e d¯ u e Many particles − + generation 2 µ c¯ s νµ; ν¯µ ¯s c µ Gibbs state − ¯ + Fermions generation 3 τ ¯t b ντ ; ν¯τ b t τ Zero temperature White dwarfs • all structure particles have spin 1/2 and neutron stars • proton p=(uud) and neutron n=(udd) Bosons Black body radiation Bose-Einstein condensation • excited states ∆++=(uuu)∗, ∆+=(uud)∗ etc. • they have spin 3/2 • p is stable, n ! p+e−+¯ν is allowed Fermions, Bosons and their Statistics Structure fermions Peter Hertel Fundamental particles charge -1 -2/3 -1/3 0 +1/3 +2/3 +1 Spin and − + statistics generation 1 e u¯ d νe ; ν¯e d¯ u e Many particles − + generation 2 µ c¯ s νµ; ν¯µ ¯s c µ Gibbs state − ¯ + Fermions generation 3 τ ¯t b ντ ; ν¯τ b t τ Zero temperature White dwarfs • all structure particles have spin 1/2 and neutron stars • proton p=(uud) and neutron n=(udd) Bosons • both have spin 1/2 Black body radiation Bose-Einstein condensation • they have spin 3/2 • p is stable, n ! p+e−+¯ν is allowed Fermions, Bosons and their Statistics Structure fermions Peter Hertel Fundamental particles charge -1 -2/3 -1/3 0 +1/3 +2/3 +1 Spin and − + statistics generation 1 e u¯ d νe ; ν¯e d¯ u e Many particles − + generation 2 µ c¯ s νµ; ν¯µ ¯s c µ Gibbs state − ¯ + Fermions generation 3 τ ¯t b ντ ; ν¯τ b t τ Zero temperature White dwarfs • all structure particles have spin 1/2 and neutron stars • proton p=(uud) and neutron n=(udd) Bosons • both have spin 1/2 Black body radiation • excited states ∆++=(uuu)∗, ∆+=(uud)∗ etc. Bose-Einstein condensation • p is stable, n ! p+e−+¯ν is allowed Fermions, Bosons and their Statistics Structure fermions Peter Hertel Fundamental particles charge -1 -2/3 -1/3 0 +1/3 +2/3 +1 Spin and − + statistics generation 1 e u¯ d νe ; ν¯e d¯ u e Many particles − + generation 2 µ c¯ s νµ; ν¯µ ¯s c µ Gibbs state − ¯ + Fermions generation 3 τ ¯t b ντ ; ν¯τ b t τ Zero temperature White dwarfs • all structure particles have spin 1/2 and neutron stars • proton p=(uud) and neutron n=(udd) Bosons • both have spin 1/2 Black body radiation • excited states ∆++=(uuu)∗, ∆+=(uud)∗ etc. Bose-Einstein condensation • they have spin 3/2 Fermions, Bosons and their Statistics Structure fermions Peter Hertel Fundamental particles charge -1 -2/3 -1/3 0 +1/3 +2/3 +1 Spin and − + statistics generation 1 e u¯ d νe ; ν¯e d¯ u e Many particles − + generation 2 µ c¯ s νµ; ν¯µ ¯s c µ Gibbs state − ¯ + Fermions generation 3 τ ¯t b ντ ; ν¯τ b t τ Zero temperature White dwarfs • all structure particles have spin 1/2 and neutron stars • proton p=(uud) and neutron n=(udd) Bosons • both have spin 1/2 Black body radiation • excited states ∆++=(uuu)∗, ∆+=(uud)∗ etc. Bose-Einstein condensation • they have spin 3/2 • p is stable, n ! p+e−+¯ν is allowed • the photon couples to charged particles only • there are also gluons which mediate strong interactions − − • e.g. n=(udd) ! (uud)+W ! p+¯νe +e • is there also a graviton G ? • is there also a Higgs boson H ? Fermions, Bosons and their Statistics Exchange bosons Peter Hertel Fundamental particles − − − − W ν¯e e ν¯µµ ν¯τ τ ud¯ cs¯ ¯tb Spin and statistics 0 + − + − + − γ; Z e e µ µ τ τ (¯νe νe ν¯µνµ ν¯τ ντ ) dd¯ uu¯ ¯ss cc¯ bb¯ ¯tt Many particles + + + + ¯ ¯ Gibbs state W e νe µ νµ τ ντ du ¯sc bt Fermions Zero + 0 − temperature • W , γ,Z ,W mediate electro-weak interaction White dwarfs and neutron stars Bosons Black body radiation Bose-Einstein condensation • there are also gluons which mediate strong interactions − − • e.g. n=(udd) ! (uud)+W ! p+¯νe +e • is there also a graviton G ? • is there also a Higgs boson H ? Fermions, Bosons and their Statistics Exchange bosons Peter Hertel Fundamental particles − − − − W ν¯e e ν¯µµ ν¯τ τ ud¯ cs¯ ¯tb Spin and statistics 0 + − + − + − γ; Z e e µ µ τ τ (¯νe νe ν¯µνµ ν¯τ ντ ) dd¯ uu¯ ¯ss cc¯ bb¯ ¯tt Many particles + + + + ¯ ¯ Gibbs state W e νe µ νµ τ ντ du ¯sc bt Fermions Zero + 0 − temperature • W , γ,Z ,W mediate electro-weak interaction White dwarfs and neutron • the photon couples to charged particles only stars Bosons Black body radiation Bose-Einstein condensation − − • e.g. n=(udd) ! (uud)+W ! p+¯νe +e • is there also a graviton G ? • is there also a Higgs boson H ? Fermions, Bosons and their Statistics Exchange bosons Peter Hertel Fundamental particles − − − − W ν¯e e ν¯µµ ν¯τ τ ud¯ cs¯ ¯tb Spin and statistics 0 + − + − + − γ; Z e e µ µ τ τ (¯νe νe ν¯µνµ ν¯τ ντ ) dd¯ uu¯ ¯ss cc¯ bb¯ ¯tt Many particles + + + + ¯ ¯ Gibbs state W e νe µ νµ τ ντ du ¯sc bt Fermions Zero + 0 − temperature • W , γ,Z ,W mediate electro-weak interaction White dwarfs and neutron • the photon couples to charged particles only stars • there are also gluons which mediate strong interactions Bosons Black body radiation Bose-Einstein condensation • is there also a graviton G ? • is there also a Higgs boson H ? Fermions, Bosons and their Statistics Exchange bosons Peter Hertel Fundamental particles − − − − W ν¯e e ν¯µµ ν¯τ τ ud¯ cs¯ ¯tb Spin and statistics 0 + − + − + − γ; Z e e µ µ τ τ (¯νe νe ν¯µνµ ν¯τ ντ ) dd¯ uu¯ ¯ss cc¯ bb¯ ¯tt Many particles + + + + ¯ ¯ Gibbs state W e νe µ νµ τ ντ du ¯sc bt Fermions Zero + 0 − temperature • W , γ,Z ,W mediate electro-weak interaction White dwarfs and neutron • the photon couples to charged particles only stars • there are also gluons which mediate strong interactions Bosons − − Black body • e.g. n=(udd) ! (uud)+W ! p+¯νe +e radiation Bose-Einstein condensation • is there also a Higgs boson H ? Fermions, Bosons and their Statistics Exchange bosons Peter Hertel Fundamental particles − − − − W ν¯e e ν¯µµ ν¯τ τ ud¯ cs¯ ¯tb Spin and statistics 0 + − + − + − γ; Z e e µ µ τ τ (¯νe νe ν¯µνµ ν¯τ ντ ) dd¯ uu¯ ¯ss cc¯ bb¯ ¯tt Many particles + + + + ¯ ¯ Gibbs state W e νe µ νµ τ ντ du ¯sc bt Fermions Zero + 0 − temperature • W , γ,Z ,W mediate electro-weak interaction White dwarfs and neutron • the photon couples to charged particles only stars • there are also gluons which mediate strong interactions Bosons − − Black body • e.g. n=(udd) ! (uud)+W ! p+¯νe +e radiation • is there also a graviton G ? Bose-Einstein condensation Fermions, Bosons and their Statistics Exchange bosons Peter Hertel Fundamental particles − − − − W ν¯e e ν¯µµ ν¯τ τ ud¯ cs¯ ¯tb Spin and statistics 0 + − + − + − γ; Z e e µ µ τ τ (¯νe νe ν¯µνµ ν¯τ ντ ) dd¯ uu¯ ¯ss cc¯ bb¯ ¯tt Many particles + + + + ¯ ¯ Gibbs state W e νe µ νµ τ ντ du ¯sc bt Fermions Zero + 0 − temperature • W , γ,Z ,W mediate electro-weak interaction White dwarfs and neutron • the photon couples to charged particles only stars • there are also gluons which mediate strong interactions Bosons − − Black body • e.g. n=(udd) ! (uud)+W ! p+¯νe +e radiation • is there also a graviton G ? Bose-Einstein condensation • is there also a Higgs boson H ? Fermions, Bosons and their Statistics Peter Hertel Fundamental particles Spin and statistics Many particles Gibbs state Fermions Zero temperature White dwarfs and neutron stars Bosons Black body radiation Bose-Einstein condensation The Aleph detector (opened) at Cern • or helicity 1/2 and -1/2 • massless structure fermions (neutrinos) have either helicity 1/2 or -1/2 • • this explains parity violation • spin and statistics are related Fermions, Bosons and their Statistics Spin 1/2 fermions Peter Hertel Fundamental particles • massive structure fermion (quarks, electrons) have spin Spin and 1/2 statistics Many particles Gibbs state Fermions Zero temperature White dwarfs and neutron stars Bosons Black body radiation Bose-Einstein condensation • massless structure fermions (neutrinos) have either helicity 1/2 or -1/2 • • this explains parity violation • spin and statistics are related Fermions, Bosons and their Statistics Spin 1/2 fermions Peter Hertel Fundamental particles • massive structure fermion (quarks, electrons) have spin Spin and 1/2 statistics Many particles • or helicity 1/2 and -1/2 Gibbs state Fermions Zero temperature White dwarfs and neutron stars Bosons Black body radiation Bose-Einstein condensation • • this explains parity violation • spin and statistics are related Fermions, Bosons and their Statistics Spin 1/2 fermions Peter Hertel Fundamental particles • massive structure fermion (quarks, electrons) have spin Spin and 1/2 statistics Many particles • or helicity 1/2 and -1/2 Gibbs state • massless
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