Thermal radiation produced by the expansion of the Universe

  title={Thermal radiation produced by the expansion of the Universe},
  author={Leonard Parker},
I show here that the expansion of the Universe can create particles with a black-body distribution. I give a simple model in which the creation of particles in an initially empty space time leads at very early times to a Friedmann expansion dominated by hot relativistic particles (probably including gravitons) having a black-body spectrum, even before classical thermalising processes have had a chance to act. If the particle creation occurs near the Planck time, the entropy produced is… 
Thermal particle production in a radiation dominated Robertson-Walker universe
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Creation of quantized particles, gravitons, and scalar perturbations by the expanding universe
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Cosmological particle production: a review
  • L. Ford
  • Physics
    Reports on progress in physics. Physical Society
  • 2021
This article will review quantum particle creation in expanding universes by focusing on the basic physical principles and on selected applications to cosmological models.
Non-gaussianities and the Stimulated creation of quanta in the inflationary universe
Cosmological inflation generates a spectrum of density perturbations that can seed the cosmic structures we observe today. These perturbations are usually computed as the result of the
Inflation in the Universe, circa 1986
The hot big bang cosmology, or the standard cosmology as it is appropriately known, is a highly successful model, providing a reliable and tested accounting of the Universe from 0.01 s after the bang


Black hole explosions?
QUANTUM gravitational effects are usually ignored in calculations of the formation and evolution of black holes. The justification for this is that the radius of curvature of space-time outside the
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The problem of quantized scalar field creation in an anisotropic spatially homogeneous background universe is reexamined from a Schr\"odinger-picture point of view. For each mode a complete set of
Black Holes and Entropy
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Particle creation by black holes
AbstractIn the classical theory black holes can only absorb and not emit particles. However it is shown that quantum mechanical effects cause black holes to create and emit particles as if they were
Standard model of the early universe
It would be unjust to brush aside the reservations-ably summarized by Burbidge (1971)-of those who do not whole-heartedly believe in a universe of finite age. Or the reservations of others who do not
The Penetration of a Potential Barrier by Electrons
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Adiabatic Invariant of the Harmonic Oscillator
The problem of a vibrating harmonic oscillator whose frequency is changing in time is considered in the case where the frequency $\ensuremath{\omega}$ is initially constant, varies in an arbitrary
  • P. S. Epstein
  • Mathematics
    Proceedings of the National Academy of Sciences of the United States of America
  • 1930
The purpose of it was to answer the question whether it is permissible to apply the ordinary rules for constructing the path of a ray to problems of radio-telegraphy, since certain layers of the atmosphere possess a considerable conductivity.