Elementary-Particle Physics Revealing the Secrets of Energy and Matter (1998) / Chapter Skim
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9 Interactions with and Connections to Other Branches of Physics and Technology
9 Interactions with and Connections to Other Branches of Physics and Technology
Pages 121-134
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From page 121... ...
This chapter indicates some of the strong areas of overlapping interest between elementary-particle physics and the disciplines of cosmology, astrophysics, nuclear physics, atomic physics, condensed-matter physics, fluid dynamics, and mathematical and computational physics. COSMOLOGY Unlike accelerator-based experiments, which are limited by available beam lines and interaction regions, the universe is an ever open laboratory.
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From page 122... ...
Indeed, astronomical and astrophysical studies may very well be a way to study some aspects of particle physics beyond the Standard Model. Particle physics interacts with cosmology on three important topics: dark matter, structure formation, and baryogenesis and nucleosynthesis.
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From page 123... ...
Elementary-particle physics provides unique insight into the nature of this component of dark matter. Candidates include neutrinos with mass, supersymmetric particles, anions, and magnetic monopoles.
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From page 124... ...
WIMPs in the halo of our galaxy that annihilate can produce high-energy positrons and gamma rays or low-energy antiprotons that can be detected by instruments placed above the atmosphere. These indirect methods complement direct detection efforts in searching for particle dark matter within our galaxy.
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From page 125... ...
As mentioned earlier, particle physics has provided several interesting possibilities for dark matter, and two attractive and very different possibilities for the origin of density inhomogeneities have been suggested. The first is that these inhomogeneities arose from quantum mechanical fluctuations during a very early, rapid period of expansion known as inflation; the second is that the seeds are topological defects, such as cosmic strings or textures, formed in a very early cosmological phase transition associated with breakdown of the symmetry between the fundamental forces.
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From page 126... ...
There is an important interplay between particle physics and big bang nucleosynthesis. The formation of light nuclei such as deuterium, 3He, 4He, and 7Li depends critically on the properties of neutrinos, such as the number of light neutrino flavors, and their mass and mixing parameters.
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From page 127... ...
The theoretical understanding of the Sun has thus been significantly advanced, leading to the strong suspicion that the physics of the neutrino itself is likely responsible for the observations. Supernovas The theory of supernova explosions depends partly on the Standard Model.
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From page 128... ...
The Telescope Array Project would view cosmic-ray initiated particle cascades in the atmosphere via their fluorescent glow. NASA is funding a 2-year feasibility study for a project to place an optical detector in Earth orbit that looks down and detects particle cascades in the atmosphere initiated by cosmic rays with energies greater than 102° eV.
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From page 129... ...
Ongoing efforts in nuclear physics study fundamental processes and symmetries with nuclei and include solar neutrino studies and tritium beta-decay experiments sensitive to neutrino masses, studies of double beta decay, and tests of parity and time-reversal violation. These areas have greatly benefited from fruitful interactions between particle physics and nuclear physics.
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From page 130... ...
There are several examples of particle physics done at atomic energies. One of the most rigorous tests of quantum electrodynamics comes from precision measurements of the Lamb shift, a slight shift in atomic energy levels due to fluctuations in the vacuum.
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From page 131... ...
For example, Richard Feynman first applied his path-integral techniques to quantum electrodynamics, the foremost particle physics problem of its day, then later to solve basic CMP problems, such as the behavior of superfluid liquid helium. Feynman diagram techniques are now universally applied in both CMP and EPP.
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From page 132... ...
This gives a description of the mass generation of all quarks, leptons, and gauge bosons, and the rest of the machinery of the Standard Model performs beautifully in all experimental tests to date. Yet, the Higgs mechanism is really just a "black box" concealing a deeper mechanism that we do not yet understand, just as the Landau-Ginzburg model was a black box containing the BCS theory.
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From page 133... ...
For example, some of the imaging techniques used in particle physics detectors could be adapted relatively easily to perform extremely fast tracking of particles seeded in a turbulent flow. Such an application would be a major boon to high Reynolds number research because the Lagrangian path of a seeded particle could be observed directly, something impossible to do today.
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From page 134... ...
Theoretical particle physicists decided to design and build parallel computers specifically for lattice gauge theory. They came up with elegant solutions to the coordination and communication problems, and the resulting machines are among the first practical examples of massively parallel computers.
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