The Physics
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Opus in profectus

The Standard Model

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Problems

practice

  1. How many confirmed elementary particles are there in the standard model?
  2. Write something.
  3. Write something.
  4. Write something.

conceptual

  1. The most common isotope of lithium is 73Li. How many of each of the following items are found in one of these atoms if it is electrically neutral?
    1. electrons
    2. baryons
    3. pentagons
    4. bonbons
    5. hadrons
    6. neutrons
    7. leptons
    8. morons
    9. protons
    10. borks
    11. sporks
    12. quarks
  2. Given locality, causality, Lorentz invariance, and physical data acquired since 1860, show that the Lagrangian describing all observed physical processes (except gravity) can be written as…

    ℒSM = − 12∂νgaμ∂νgaμ − gsfabc∂μgaνgbμgcν − 14g2sfabcfadegbμgcνgdμgeν + 12ig2s(q̅σiγμqσj)gaμ + G̅a∂2Ga + gsfabc∂μG̅aGbgcμ − ∂νW+μ∂νW−μ − M2W+μW−μ − 12∂νZ0μ∂νZ0μ − 12c2wM2Z0μZ0μ − 12∂μAν∂μAν − 12∂μH∂μH − 12m2hH2 − ∂μφ+∂μφ− − M2φ+φ− − 12∂μφ0∂μφ0 − 12c2wMφ0φ0 − βh[2M2g2 + 2MgH+ 12(H2 + φ0φ0 + 2φ+φ−)] + 2M4g2αh − igcw[∂νZ0μ(W+μW−ν − W+νW−μ) − Z0ν(W+μ∂νW−μ − W−μ∂νW+μ) + Z0μ(W+ν∂νW−μ − W−ν∂νW+μ)] − igsw[∂νAμ(W+μW−ν − W+νW−μ) − Aν(W+μ∂νW−μ − W−μ∂νW+μ) + Aμ(W+ν∂νW−μ − W−ν∂νW+μ)] − 12g2W+μW−μW+νW−ν + 12g2W+μW−νW+μW−ν + g2c2w(Z0μW+μZ0νW−ν − Z0μZ0μW+νW−ν) + g2s2w(AμW+μAνW−ν − AμAμW+νW−ν) + g2swcw[AμZ0ν(W+μW−ν − W+νW−μ)− 2AμZ0μW+νW−ν] − gα[H3 + Hφ0φ0 + 2Hφ+φ−] − 18g2αh[H4 + (φ0)4 + 4(φ+φ−)2 + 4(φ0)2φ+φ− + 4H2φ+φ− + 2(φ0)2H2] − gMW+μW−μH − 12gMc2wZ0μZ0μH − 12ig[W+μ(φ0∂μφ− − φ−∂μφ0)− W−μ(φ0∂μφ+ − φ+∂μφ0)] + 12g[W+μ(H∂μφ− − φ−∂μH)− W−μ(H∂μφ+ − φ+∂μH)] + 12g1cwZ0μ(H∂μφ0 − φ0∂μH) − igs2wcwMZ0μ(W+μφ− − W−μφ+) + igswMAμ(W+μφ− − W−μφ+) − ig1 − 2c2w2cwZ0μ(φ+∂μφ− − φ−∂μφ+) + igswAμ(φ+∂μφ− − φ−∂μφ+) − 14g2W+μW−μ[H2 + (φ0)2 + 2φ+φ−] − 14g21c2wZ0μZ0μ[H2 + (φ0)2+ 2(2s2w − 1)2φ+φ−] − 12g2s2wcwZ0μφ0(W+μφ− + W−μφ+) − 12ig2s2wcwZ0μH(W+μφ− − W−μφ+) + 12g2swAμφ0(W+μφ− + W−μφ+) + 12ig2swAμH(W+μφ− − W−μφ+) − g2swcw(2c2w − 1)Z0μAμφ+φ− − g1s2wAμAμφ+φ− − e̅λ(γ∂ + mλe)eλ − ν̅λγ∂νλ − u̅λj(γ∂ + mλu)uλj − d̅λj(γ∂ + mλd)dλj + igswAμ[− (e̅λγμeλ) + 23(u̅λjγμuλj) − 13(d̅λjγμdλj)] + ig4cwZ0μ[(ν̅λγμ(1 + γ5)νλ) + (e̅λγμ(4s2w − 1 − γ5)eλ) + (u̅λjγμ(43s2w − 1 − γ 5)uλj) + (d̅λjγμ(1 − 83s2w − γ5)dλj)] + ig2√2W+μ[(ν̅λγμ(1 + γ5)eλ) + (u̅λjγμ(1 + γ5)Cλκdκj)] + ig2√2W−μ[(e̅λγμ(1 + γ5)νλ) + (d̅κjC†λκγμ(1 + γ5)uλj)] + ig2√2mλeM[− φ+(ν̅λ(1 − γ5)eλ) + φ−(e̅λ(1 + γ5)νλ)] − g2mλeM[H(e̅λeλ) + iφ0(e̅λγ5eλ)] + ig2M√2φ+[− mκd(u̅λjCλκ(1 − γ5)dκj) + mλu(u̅λjCλκ(1 + γ5)dκj)] + ig2M√2φ−[mλd(d̅λjC†λκ(1 + γ5)uκj) − mκu(d̅λjC†λκ(1 − γ5)uκj)] − g2mλuMH(u̅λjuλj) − g2mλdMH(d̅λjdλj) + ig2mλuMφ0(u̅λjγ5uλj) − ig2mλdMφ0(d̅λjγ5dλj) + X̅+(∂2 − M2)X+ + X̅−(∂2 − M2)X− + X̅0(∂2 − M2c2w)X0 + Y̅∂2Y + igcwW+μ(∂μX̅0X− − ∂μX̅+X0) + igswW+μ(∂μY̅X− − ∂μX̅+Y) + igcwW−μ(∂μX̅−X0 − ∂μX̅0X+) + igswW−μ(∂μX̅−Y − ∂μY̅X+) + igcwZ0μ(∂μX̅+X+ − ∂μX̅−X−) + igswAμ(∂μX̅+X+ − ∂μX̅−X−) − 12gM[X̅+X+H + X̅−X−H + 1c2wX̅0X0H] + 1 − 2c2w2cwigM[X̅+X0φ+ − X̅−X0φ−] + 12cwigM[X̅0X−φ+ − X̅0X+φ−] + igMsw[X̅0X−φ+ − X̅0X+φ−] + 12igM[X̅+X+φ0 − X̅−X−φ0]

    Source: Thomas D. Gutierrez, 1999