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The Incredible Foresight of ETTORE MAJORANA Haim Harari Erice, September 1, 2006. Neutrino Masses, Leptogenesis and Beyond. The Foresight. Can you tell a neutrino from an anti-neutrino ?. MAJORANA. n may be its own antiparticle !. Is n Massless or Very Light ?.
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The Incredible Foresight of ETTORE MAJORANA Haim Harari Erice, September 1, 2006 Neutrino Masses, Leptogenesis and Beyond
The Foresight Can you tell a neutrinofrom an anti-neutrino? MAJORANA n may be its own antiparticle !
Is nMassless or Very Light? “Direct” experiments m (ne) < few eV Theory No good reason for massless n. Simple argument for very light n. n is the only “chargeless” particle. All quarks and leptons “Dirac Mass” n also “Majorana Mass”
0 m m L Is nMassless or Very Light? M1 ~ O(L) M2 ~ O(m2/L) “See-Saw” L m n Majorana Mass Gell-Mann, Ramond, Slansky, Yanagida
Solar Neutrinos The sun emits 1038n per second. 1029 go to direction earth. Per 100 ton detector - 40 hits per month Homestake n + Cl37 e +A37 400 ton C2Cl4 Mikheyev-Smirnov-Wolfenstein
Kamiokande Super - Kamiokande Kamiokande n+ n e + p 50,000 ton/clean water
GALLEX n + Ga71e +Ge71 30 ton
GALLEX n + Ga71e +Ge71 30 ton SNO 1000 ton D2O (+2 ton Salt) 10,000 phototubes ne + d e + p + p (charged Current) nx + dnx + p + n (Neutral Current) nx + e nx +e (Elastic Scattering) Count total n – flux and ne - flux
Solar Model is Right! Neutrinos Oscillate Neutrinos have Mass m(nm) ~ 8 meV q12Large
Kamland – Japan R R KAM R R L ~ 180 km E ~ O (MeV) Probe: ∆m2<<eV2
KAMIOKANDE: N(nm) N(ne) = 1.2 !!! m(nt) ~ 50 meV Cosmic Radiation Energetic protons arrive p Pions created in atmosphere In p-decay: N(nm) N(ne) atmosphere p = 2 m e ne nm nm earth
The Universe 70% Dark Energy 25% Dark Matter 4% H, He 0.5% Heavy Nuclei 0.5% Neutrinos m(nt) ~ 50 meV m(nm) ~ 8 meV m(ne) ~ smaller Large angles! Also K2K, MINOS,others
meV meV eV keV MeV GeV TeV -6 -5 -4 -3 -2 -1 -0 1 2 3 4 5 6 7 8 9 10 11 12 2nd 3rd Generation 1st Q c u t 2/3 s d b -1/3 Quarks ne? nm? nt? 0 m t e -1 Leptons ( ) ( ) ( ) u d c s t b “The Standard Model” ( ) ( ) ( ) ne e nm m nt t
meV meV eV keV MeV GeV TeV -6 -5 -4 -3 -2 -1 -0 1 2 3 4 5 6 7 8 9 10 11 12 2nd 3rd Generation 1st Q c u t 2/3 s d b -1/3 Quarks nt nm ne? 0 t e m -1 Leptons ( ) ( ) ( ) u d c s t b “The Standard Model” ( ) ( ) ( ) ne e nm m nt t
Why are we here? B-Violation (also L-Violation) CP-Violation Non-equilibrium (also no “wash-out”) Sakharov-1967 B-Violation (and L-Violation) p-decay GUT scale or higher Not seen (but SN87A!) n-oscillations and mass CP-Violation KM phase for quarks (requires 3 generations) CP-violation in leptons (requires 2 generations) WHEN AND HOW DID IT HAPPEN?
Why are we here? At Big Bang: B=0 , L=0 (also B-L=0) We need to create a nonzeroB (also B-L?) “Leptogenesis”(other theories: GUT, electroweak) : If we could create a nonzero L and then trade B for L, we could create a positive B. IT IS NOT ENOUGH TO TRADE B for L WE MUST ALSO CREATE B-L
B – L is conserved (and must be nonzero) B + L is violatede.g. D(B + L) = 6 is allowed B and L violation in the standard model (but no B-L) (qiqjqk) (qiqjqk) (qiqjqk) (ℓiℓjℓk) “instanton” terms: i,j,k = generations “SPHALERON”: Connecting degenerate ground states L and B can change (together) each by 3 UNITS (for Ng =3) THE STANDARD MODEL CREATES (together) B AND L
Note: • ↔ n is possible u d d u n e- Neutrino oscillations m(n) ≠ 0, very small m2 M 0 m m M Seesaw mechanism: m(n) ~ Hence: n is a Majorana neutrino <nn> ≠ 0, n-nmixing, heavy neutrino with mass M L=0 AT BIG BANG BUT DL ≠ 0 PROCESSES ARE ABUNDANT ! The universe is made of QUARKS and LEPTONS e+ n
The particle, which is its own antiparticle, is responsible for having more particles than antiparticles in the universe LEPTOGENESIS At BigBang: B = L = 0. Majorana: DL≠0 and D(B-L)≠0are allowed. Hence, the universe has L≠0 and B-L≠ 0 . LEADING TO B≠0 !!! (Elaborate quantitative estimates). e.g. Buchmueller-Peccei-Yanagida NEUTRINO COGITO ERGO SUM
And in 2056 – for Majorana’s 150th birthday . Perhaps it all happens at the subparticle level !? Warning No evidence for subquarks and subleptons. No reasonable dynamical theory
Why q and ℓhave simple charge ratios? ( +2/3, -1/3 ) (0, -1) The Quark - Lepton Connection Why p and e+ have same charge? Why SQi = 0 for q’s and ℓ’s in one generation? [ SQi = (-1) + (0) + 3(+2/3) +3(-1/3) = 0 ] Why three colors and three generations? PREONS? TOY MODELS?
Q SU(3) SU(3) N N 3(B-L) V H T C T 3 3 1 0 1 + 1/3 V 0 3 3 0 1 -1 V 0 3 3 0 -1 1 - 1/3 T 3 3 -1 0 -1 color color n d u e- VVV VVT VTT TTT (0) (- 1/3) (- 2/3) (-1) 1 3 3 1 e+ u d n TTT TTV TVV VVV (+1) (+2/3) (+1/3) (0) 1 3 3 1 “Antimatter” “Matter” e- TTT e+ TTT p TTT(TT)(VV)(VV) p TTT(TT)(VV)(VV) HH+Seiberg Rishons SU(3)H Singlets Anomaly cancellation: NH = NC = NG = 3 Buchmann+Schmid
HH+Seiberg Q SU(3) SU(3) N N 3(B-L) V H T C T 3 3 1 0 1 + 1/3 V 0 3 3 0 1 -1 V 0 3 3 0 -1 1 - 1/3 T 3 3 -1 0 -1 color color n d u e- VVV VVT VTT TTT (0) (- 1/3) (- 2/3) (-1) 1 3 3 1 e+ u d n TTT TTV TVV VVV (+1) (+2/3) (+1/3) (0) 1 3 3 1 “Antimatter” “Matter” Rishons SU(3)H Singlets TO BREAK B-L WE NEED TO BREAK N Simplest J=0, Q=0, SU(3)H – singlet, SU(3)C – singlet IS <VVVVVV> : BREAKS L, HENCE CREATES B V <VVVVVV>≠0 ERGO SUM
Measuring Masses and Angles Clues for Theory “Beyond the Standard Model” Neutrino Astronomy UHE Cosmic Neutrinos Dark Matter Z nn nin Nucleosynthesis - Less Double-Decay n- Decays n -Magnetic Moments Heavy n Sterile n
ETTORE MAJORANA WAS NO FOOL WAS BRILLIANT !!! Neutrino Masses, Leptogenesis and Beyond