Beyond the God Particle
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15. Fermilab is playing an active role in this development with a trial liquid argon detector experiment called MicroBooNE: “ArgoNeuT,” http://www.fnal.gov/pub/science/experiments/intensity/argoneut.html; “MicroBooNE,” http://www-microboone.fnal.gov/ (sites last visited 3/26/2013). Liquid argon-based time-projection chambers are also under active study for dark matter and neutrinoless double-beta decay detection, addressing the issue of Majorana vs. Dirac neutrino masses.
16. See “Proton decay,” http://en.wikipedia.org/wiki/Proton_decay (site last visited 3/26/2013).
CHAPTER 11. PROJECT X
1. “The Shutdown Process,” http://www.fnal.gov/pub/tevatron/shutdown-process.html (site last visited 3/26/2013).
2. John Matson, “Life after Tevatron: Fermilab Still Kicking Even Though It Is No Longer Top Gun,” Scientific American (January 2012), http://blogs.scientificamerican.com/observations/2012/01/31/life-after-tevatron-fermilab-still-kicking-even-though-it-is-no-longer-top-gun/ (site last visited 1/23/2013). The lessons from the Tevatron are interesting. The top quark was initially thought to be light, about 90 GeV, and it should then have been seen in the first year of running. However, the top quark has turned out to have a very large mass of 172 GeV, and this required several years of patient searching until evidence for it finally emerged at the Tevatron, followed by a bona fide discovery in 1995. Had the top quark been about 60 GeV heavier we may never have found it at the Tevatron.
It was estimated in 1991 that, if the Higgs was lighter than about 140 GeV, the Tevatron could see it with 30 inverse femtobarns of data. The Tevatron luminosity increased significantly, due to the heroic efforts of the Fermilab Accelerator Division, to the point that it became clear the Higgs could have been seen with a concerted effort by the lab. The prediction for the required luminosity turned out to be right on the nose, but unfortunately the Tevatron ended operations, having delivered one-third of the required Higgs discovery's integrated luminosity. Still, the decay mode, by which there is now some evidence of the Higgs boson at the Tevatron, is the decay of Higgs into a b quark + anti–b quark final state. This decay mode is very important to our understanding of the Higgs properties. But this mode, and other “matter decay modes,” of the Higgs will be established in the all-important LHC run, due to commence January 1, 2015.
3. See Fermilab's Project X website: http://projectx.fnal.gov/; in particular, one can access the “Project X Book” at this site, which gives comprehensive literature on the experimental program and machine and detector designs. See also “Project X (accelerator),” http://en.wikipedia.org/wiki/Project_X_%28accelerator%29; “Fermilab's Project X Could Offer Potential Energy Applications,”http://www.symmetrymagazine.org/breaking/2011/04/12/fermilabs-project-x-may-have-a-potential-energy-application (sites last visited 1/23/2013).
4. “Muon Storage Ring”: http://www.cap.bnl.gov/mumu/studyii/final_draft/chapter-7/chapter-7.pdf; “Muon Ring Could Act as a Neutrino Factory,” http://cerncourier.com/cws/article/cern/28043 (sites last visited 1/23/2013).
5. “The E821 Muon (g-2) Home Page,” http://www.g-2.bnl.gov/; “Muon g-2,” http://muon-g-2.fnal.gov/ (sites last visited 6/24/2013).
6. See “Neutrino Factory,” http://en.wikipedia.org/wiki/Neutrino_Factory (site last visited 4/3/2013).
7. See “Muon collider,” http://en.wikipedia.org/wiki/Muon_Collider (site last visited 4/3/2013).
8. The charged-kaon decay mode has been previously studied by the Brookhaven E787/949 experiment using a high- intensity stopped-kaon technique to yield a total of seven candidate signal events. The NA62 experiment at CERN is currently pursuing a new in-flight technique with the aim of achieving a 100-event sensitivity at the Standard Model level. The process KL → π v v is a purely CP-violating process, that is predicted in the Standard Model theoretically at the 1 percent level of precision. The observation and precise measurement of this rare process will constitute a major triumph in kaon physics with the potential of discovering discrepancies. The KOTO experiment at J-PARC in Japan is pursuing a staged approach to reach single-event sensitivity, with an ultimate goal of reaching 100-event sensitivity, at the Standard Model level. This establishes the need for a multi-1,000-event future Project-X-based experiment.
9. See “Quantum electrodynamics,” http://en.wikipedia.org/wiki/Quantum_Electrodynamics, “Richard Feynman,” http://en.wikipedia.org/wiki/Richard_Feynman, “Julian Schwinger,” http://en.wikipedia.org/wiki/Julian_Schwinger, “Sin-Itiro Tomonaga,” http://en.wikipedia.org/wiki/Sin-Itiro_Tomonaga (sites last visited 4/3/2013).
10. We say that electric fields are vectors (they reflect like velocities or position vectors in mirrors); magnetic fields are “pseudo-vectors” and reflect with an opposite sign in mirrors. One has to be a little careful with this, because with vectors it depends upon the orientation of the system and of the mirror.
11. Also, it should be noted that EDM experiments provide very sensitive limits on the existence of electric dipoles and have already bitten the theorists in the pants. The current upper limit on the existence of the electron EDM is about 10-27 e-cm coming from studying “polar molecules” like Yb-F (see, e.g., “A New Upper Limit on the Electron's Electric Dipole Moment,” Physics Today 12 [August 2011]). This result already severely constrained the Minimal Supersymmetric Standard Model (MSSM) model, before the LHC arrived on the scene. We believe that supersymmetry has a very good chance of being true, but perhaps only at extremely high and inaccessible energy scales, and perhaps in a novel form that no one has yet conceived of.
12. See “Electron electric dipole moment,” http://en.wikipedia.org/wiki/Electron_electric_dipole_moment, “Neutron electric dipole moment,” http://en.wikipedia.org/wiki/Neutron_electric_dipole_moment (sites last visited 4/3/2013).
13. See “Proton therapy,” http://en.wikipedia.org/wiki/Proton_therapy (sites last visited 4/7/2013).
14. “Accelerator Driven Subcritical Reactors,” http://www.academia.edu/1684005/Accelerator_Driven_Subcritical_Reactors; “Accelerator-Driven Nuclear Energy,” http://www.world-nuclear.org/info/Current-and-Future-Generation/Accelerator-driven-Nuclear-Energy/#.UVX7efKbFXs (sites last visited 4/3/2013). Much more can be found by searching online for “accelerator driven subcritical reactors.” See also R. P. Johnson et al., “GEM*STAR—New Nuclear Technology to Produce Inexpensive Diesel Fuel from Natural Gas and Carbon,” Proceedings of IPAC2013, Shanghai, China.
15. “Muon Accelerator Program,” http://map.fnal.gov/ (site last visited 4/7/2013).
CHAPTER 12. BEYOND THE HIGGS BOSON
1. For in introduction to the cosmological theory, see Steven Weinberg, The First Three Minutes (New York: Basic Books, 1977). Search online for “cosmology” and “big bang” for various wiki articles.
2. See “Nimitz-class aircraft carrier,” http://en.wikipedia.org/wiki/Nimitz-class_aircraft_carrier, “Gerald R. Ford–class aircraft carrier,” http://en.wikipedia.org/wiki/Gerald_R._Ford-class_aircraft_carrier; Ronald O'Rourke, “Navy CVN-21 Aircraft Carrier Program: Background and Issues for Congress,” http://www.history.navy.mil/library/online/navycvn21.htm (sites last visited 4/7/2013).
3. Estimated shale oil alone is 1.5 trillion barrels, which at $100/bbl is $150 trillion. See, e.g., http://dailyreckoning.com/oil-shale-reserves/; see also http://abcnews.go.com/Business/american-oil-find-holds-oil-opec/story?id=17536852#.UVcVQPKbFXs. Note the word “estimated” is key here, since proven reserves are significantly less and don't include shale. Estimated coal and natural gas reserves are comparable (sites last visited 4/7/2013).
4. See, e.g., http://rutledgecapital.com/2009/05/24/total-assets-of-the-us-economy-188-trillion-134xgdp/. This article essentially asks the sensible question “Why are we sweating the $17 trillion debt when we have $200 trillion in assets?” (site last visited 4/7/2013).
5. See http://www.forbes.com/forbes-400/list/ (site last visited 4/7/2013).
6. “Conjecture on the Physical Implications of the Scale Anomaly,” invited talk on the occasion of the 75th bir
thday celebration of Murray Gell-Mann (“Murraypalooza”), Christopher T. Hill (2005), downloadable pdf file at http://arxiv.org/pdf/hep-th/0510177.pdf and references therein.
7. Steven Weinberg, “The Crisis of Big Science,” New York Times Book Review, May 10, 2012, http://www.nybooks.com/articles/archives/2012/may/10/crisis-big-science/ (site last visited 3/8/2013).
APPENDIX
1. See “Quark,” http://en.wikipedia.org/wiki/Quark, “Murray Gell-Mann,” http://en.wikipedia.org/wiki/Gell-Mann, “George Zweig,” http://en.wikipedia.org/wiki/George_Zweig (sites last visited 3/13/13). When Gell-Mann proposed the term “quark,” borrowed from the passage in James Joyce's novel Finnegans Wake: “Three quarks for Muster Mark,” he thankfully broke the tradition that everything requires a Greek alphabetical symbol for nomenclature in particle physics. The idea of quarks was also independently proposed by George Zweig, a colleague of Gell-Mann at Caltech who happened to be on a visit to CERN and wrote down the idea in a famous unpublished CERN preprint. Zweig chose the name “aces.” Zweig realized that certain dynamical properties of the many newly discovered particles could be explained on the basis of the next layer of matter, the quarks.
2. See “James D. Bjorken,” http://en.wikipedia.org/wiki/Bjorken, “Deep inelastic scattering,” http://en.wikipedia.org/wiki/Deep_inelastic_scattering (sites last visited 3/13/13).
3. See “Quantum chromodynamics,” http://en.wikipedia.org/wiki/Quantum_chromodynamics; Frank Wilczek, “QCD Made Simple,” http://www.frankwilczek.com/Wilczek_Easy_Pieces/298_QCD_Made_Simple.pdf (sites last visited 3/13/13).
4. See “Generation (particle physics),” http://en.wikipedia.org/wiki/Generation_%28particle_physics%29 (site last visited 3/13/13). We actually have some understanding of the fact that the charges of a generation must add to zero because of the cancelation of the Adler-Bardeen-Bell-Jackiw anomalies, a quantum threat to the symmetries in the weak interactions that must be perfectly canceled to zero. We also have beautiful “unified theories,” such as the Georgi–Glashow SU(5) theory that “predicts” this pattern. However, in any theory, we can't be absolutely sure that the electron goes with the u and d quarks, as opposed to the t and b quarks, or some other scrambling of things.
The CP violation observed in quarks does require all three generations, for technical reasons, and we also know that some kind of CP violation is necessary for matter to exist in the universe at all. Also, all quarks and leptons are active in the early universe and play a role in the formation of the universe we end up with.
5. The number of gluons is 8 = 9 – 1. 9 is the number of (color, anti-color) pairs that we can ever possibly have. One combination, , is not an SU(3) group element. That is, it doesn't rotate anything in color space and doesn't arise as a gluon.
6. See also “Spin (physics),” http://en.wikipedia.org/wiki/Spin_%28physics%29 (site last visited 3/13/13).
7. See “Wave function,” http://en.wikipedia.org/wiki/Wave_function (site last visited 3/13/13).
8. See “Boson,” http://en.wikipedia.org/wiki/Bosons, “Fermion,” http://en.wikipedia.org/wiki/Fermion (sites last visited 3/13/13).
9. See “James Clerk Maxwell,” http://en.wikipedia.org/wiki/James_Clerk_Maxwell (site last visited 3/13/13). Maxwell, Scottish born and living only to age 48, is a towering figure in the history of science. His importance in the history of physics is comparable to that of Einstein and Newton. He was the first to recognize that light is a propagating wave disturbance of electric and magnetic fields, and was responsible for finding a solution to the equations that describe all electric and magnetic phenomena, known as Maxwell's equations. The laws of special relativity are already contained in Maxwell's theory—Einstein unearthed them by contemplating the symmetries of the equations under different states of inertial motion.
10. J. D. Jackson and L. B. Okun, “Historical Roots of Gauge Invariance,” Reviews of Modern Physics 73 (2001): 663–80; John P. Ralston (private communication); Jackson and Okun write:
Notable in this regard, but somewhat peripheral to our history of gauge invariance, was James MacCullagh's early development of a phenomenological theory of light as disturbances propagating in a novel form of the elastic ether, with the potential energy depending not on compression and distortion but only on local rotation of the medium in order to make the light vibrations purely transverse…. MacCullagh's equations correspond (when interpreted properly) to Maxwell's equations for free fields in anisotropic media. We thank John P. Ralston for making available his unpublished manuscript on MacCullagh's work.
Thus, MacCullagh actually constructed a theory of light as a propagating wave disturbance in a material medium, an “ether,” in 1839. This theory is equivalent to Maxwell's theory, of some 25 years later, and it involves the concept of an unobservable gauge field, hence MacCullagh seemed to have understood the symmetry principle that is required. But the connection of the underlying physical picture here, involving the concept of twists, or local rotations, in a material medium, to electrodynamics is remote. This discovery has gone almost completely unnoticed. MacCullagh, whose relationships with the rest of the physics community were not happy ones, and whose life ended tragically in suicide, may have been a man too far ahead of his time.
11. See “Gauge theory,” http://en.wikipedia.org/wiki/Gauge_theory, http://en.wikipedia.org/wiki/Introduction_to_gauge_theory, “Yang–Mills theory,” http://en.wikipedia.org/wiki/Yang%E2%80%93Mills_theory (sites last visited 3/13/13). More mathematically, we can describe the gauge invariance of electrodynamics: We consider a complex phase factor, which is just an exponential, like eiθ, where θ is real, and this has a magnitude of unity, i.e., 1 = | eiθ |2. We also consider the electron wave function, which is a complex valued function of space and time, . Multiplying the electron wave function by this factor means doesn't change the magnitude of the electron's wave function, and it therefore shouldn't affect the measured probabilities .
12. See “Feynman diagrams,” http://en.wikipedia.org/wiki/Feynman_diagrams (site last visited 3/13/13).
13. See “Yang–Mills Theory,” http://en.wikipedia.org/wiki/Yang-Mills; see also “Special unitary group,” under “n = 2,” http://en.wikipedia.org/wiki/SU%282%29#n_.3D_2 (sites last visited 3/13/13).
14. See “Standard Model,” http://en.wikipedia.org/wiki/Standard_Model (site last visited 3/13/13).
aberration in lenses. See lens
accelerator. See particle accelerator
accelerator driven (subcritical) nuclear reactors (ADS), 236–237
AGS (Brookhaven National Laboratory accelerator), 182
ALICE (CERN LHC detector), 26
Alice, of Lewis Carroll, 66, 68, 78, 92, 210–215
alpha particle, 48, 198
Anderson, Carl, 60, 203
angular momentum. See spin
antimatter 198–204
Apollo 11, 84
Apollo 13, 30
ATLAS (CERN LHC detector), 20, 26, 81, 187, 277
atom, 39, 46–52
atomic nucleus. See nucleus
Bardeen, John, 102
Becquerel, Henri, 196–197, 208, 230–231, 241, 250, 275
Berners-Lee, Tim, 14, 18, 188
beta decay, 204–209, 218
beta rays, 197–198
Bjorken, James, 255
Bohr, Niels, 21, 49–50, 159, 204
Boltzmann, Ludwig, 37
Bose, Satyendra Nath, 140
Bose-Einstein condensate, 140–142, 267–268
boson, 23, 140, 256–269
Bristol, University of, 62
Broglie, Louis de, 21, 159
Brookhaven National Laboratory, 72, 182, 207, 232
C. See charge conjugation
CDF (Fermilab Tevatron detector), 184, 188, 229
CERN, 12–15, 19–28, 34, 81, 93, 147, 149, 277
Chacaltaya, in Andes, 62
charge conjugation (C), 212–215
Charpak, Georges, 188
chemistry, chemical reactions, 40–42
chirality, 117–126, 127–135, 138–148, 210, 211, 220–224
CMS (CERN LHC detector), 20, 26, 81, 187, 277
Columbia University, Columbia Accelerator, 70–80
compound lens. See lens
Congress. See US Congress
Conseil Européen pour la Recherche Nucléaire. See CERN
conservation of charge. See gauge symmetry; electric charge; weak charge
continuous wave linac (Project X), 234
Cooper, Leon; Cooper pair, 102, 268
corkscrew. See chirality
cosmic rays, 51–52, 55, 57, 60–63
Coulomb, Charles-Augustin de, 162
Cowan, Clyde, 206
CPT, 212–215
CP violation, 213–215, 233–238
cyclotron, 179–180
Curie, Marie and Pierre, 196–198, 230, 241, 250
D-Zero (Fermilab Tevatron detector) 184, 188, 229
dark matter, 246–247
Davis, Ray, 225
Davisson, Joseph, 159
Democritus of Athens, 37–39, 94–95
detectors, 188–189. See also ATLAS; CMS
Dirac, Paul, 198–204, 266, 257
DNA, 35, 46
Edwards, Helen, 229
Einstein, Albert, 20, 21, 30–31, 43, 88, 90–91, 101, 140, 159, 198
electric charge, 46–50, 74, 128, 135–140, 160–164, 174–175, 270
electric current, 174–179
electric dipole moment (EDM) 231, 235–238
electric field, 141, 160–164, 169–171, 270
electromagnetic lens. See lens
electromagnetism, 23, 46–50, 126, 136–138, 270
electron, 23, 46–50, 57–58, 64, 163–169, 185–186, 189–190, 195, 198–204, 209, 254, 269–275
electron microscope, 46, 158, 164–167
electron volt, 41–42, 46–47, 51