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Updated: Jul 28, 2026

Measurement of Particle Size Distribution in Turbid Solutions by Dynamic Light Scattering Microscopy
Published on: January 9, 2017
Implications of a primordial origin for the dispersion in D/H in quasar absorption systems
C J Copi1, K A Olive, D N Schramm
1Case-Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-7079, USA.
Abstract:
We explore the difficulties with a primordial origin of variations of D/H in quasar absorption systems. In particular we examine options such as a very large-scale inhomogeneity in the baryon content of the universe. We show that very large-scale (much larger than 1 Mpc) isocurvature perturbations are excluded by current cosmic microwave background observations. Smaller-scale ad hoc perturbations (approximately 1 Mpc) still may lead to a large dispersion in primordial abundances but are subject to other constraints.
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