Cosmological experiments in liquid helium
نویسنده
چکیده
Fast passage through a continuous phase transition is expected to result in the creation of topical defects via the Kibble mechanism. Recent experiments involving the expansion of a small volume of liquid He through the lambda (superfluid) transition, as a model of the GUT (grand unified theory) symmetrybreaking transition of the early universe, are discussed and set in context. Copious creation of quantized vortices, analogous to cosmic strings, is expected but not observed. The possibility of developing a more sensitive version of the experiment is considered.
منابع مشابه
Wavelength and polarization variations of InAs/GaAs quantum dots emission at liquid Helium temperature via microphotoluminescence spectroscopy
In this paper, we investigate variation of the wavelength, intensity and polarization of the self-assembled InAs/GaAs quantum dots emission by microphotoluminescence spectroscopy at the liquid helium temperature. The microcavity wafer sample is grown by molecular beam epitaxy (MBE) and chemically etched into the micropillar structure (with elliptical cross section - long and short axis 2µm×1.5µ...
متن کاملWavelength and polarization variations of InAs/GaAs quantum dots emission at liquid Helium temperature via microphotoluminescence spectroscopy
In this paper, we investigate variation of the wavelength, intensity and polarization of the self-assembled InAs/GaAs quantum dots emission by microphotoluminescence spectroscopy at the liquid helium temperature. The microcavity wafer sample is grown by molecular beam epitaxy (MBE) and chemically etched into the micropillar structure (with elliptical cross section - long and short axis 2µm×1.5µ...
متن کاملJu l 1 99 6 COSMOLOGICAL EXPERIMENTS IN CONDENSED MATTER SYSTEMS
Topological defects are thought to be left behind by the cosmolog-ical phase transitions which occur as the universe expands and cools. Similar processes can be studied in the phase transitions which take place in the laboratory: " Cosmological " experiments in superfluid He 4 and in liquid crystals were carried out within the past few years, and their results shed a new light on the dynamics o...
متن کاملA Cosmological Experiment in Liquid Helium
ALTHOUGH the birth of the universe is inaccessible to human experimental investigation, aspects of cosmological theories can nonetheless be explored in the laboratory. Tiny inhomogeneities in the mix of particles and radiation produced in the Big Bang grew into the clusters of galaxies that we see today, but how those inhomogeneities arose and grew is still unclear. Cosmologies based on grand u...
متن کاملReexamining the Constraint on the Helium Abundance from CMB
We revisit the constraint on the primordial helium mass fraction Yp from observations of cosmic microwave background (CMB) alone. By minimizing χ of recent CMB experiments over 6 other cosmological parameters, we obtained rather weak constraints as 0.17 ≤ Yp ≤ 0.52 at 1σ C.L. for a particular data set. We also study the future constraint on cosmological parameters when we take account of the pr...
متن کامل