A Cosmological Model Based on a Quadratic Equation of State Unifying Vacuum Energy, Radiation, and Dark Energy

<table>Evolution of the density <svg height="12.175" id="M669" style="vertical-align:-3.56265pt" version="1.1" viewbox="0 0 9.2875004 12.175" width="9.2875004" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> with the time <svg height="10.3875" id="M670" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 5.9250002 10.3875" width="5.9250002" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> in linear scales. General relativity (cosmological constant) limits the decay of the density to the cosmological value <svg height="20.875" id="M671" style="vertical-align:-4.0404pt" version="1.1" viewbox="0 0 150.675 20.875" width="150.675" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>.</table>

Journal of Gravity

fig14

Figure 14

Figure 14: A Cosmological Model Based on a Quadratic Equation of State Unifying Vacuum Energy, Radiation, and Dark Energy 