Big Bang era Comparison Table

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Big Bang era comparison table

Subject has start time has definition is preceded by has density has synonym is followed by has duration has temperature

Big bang crossover effect 10¹² s The epoch during the radiation era when the universe switched from being radiation-dominated to being matter-dominated. world point

hadron era 10^-43 s after Big Bang The Big Bang era during which quantum and general-relativistic effects are expected to modify each other in an unknown way. Planck era ρ = 10⁹³ g cm^-3 hadron barrier lepton era 10^-5 s

inflation era 10^-35 s Big Bang era in which the infant universe went through a brief period of extremely rapid (exponential) expansion, after which it settled back into the more leisurely rate of expansion of the standard model. The period of rapid expansion began and ended when the universe was still much less than a second old, yet it provides a physical explanation for the flatness and horizon puzzles. The inflationary universe model also suggests that the universe is vastly larger than the portion of it that is visible to us. (See exponential expansion.) world point

lepton era 10^-5 s after Big Bang The Big Bang era when the temperature had dropped to about 10¹² K and when the Universe consisted mainly of leptons and photons. It lasted until the temperature fell below 10¹⁰ K. At this stage, the characteristic photon energy fell below the rest mass energy of an electron, and the abundance of electron-positron pairs fell by many orders of magnitude. Only one electron survived for every 10⁸ photons. The universe was subsequently radiation-dominated (substantial numbers of neutrinos were also present, but they did not interact directly with the matter or the radiation). hadron era world point nucleosynthetic era 1 s 10¹⁰ K to 10¹² K

matter era 10¹² s The release of photons from constant collisions with massive particles as the universe expanded and its matter density diminished. See decoupling. radiation era decoupling era > 10¹⁰ years 3 K to 3000 K

nucleosynthetic era 1 s after the Big Bang The Big Bang era when neutrons were produced and helium and deuterium were synthesized. At t = 200 sec, nucleosynthesis began rather abruptly and virtually all deuterium was synthesized to helium. lepton era world point radiation era 1000 s

Planck era 0 s after Big Bang The Big Bang era, prior to which Einstein's theory of gravitation breaks down and a quantized theory of gravity is needed. Density was so high that gravitational force acted as strongly as the other fundamental forces on the sub-atomic scale. Big Bang world point hadron era, inflation era 10^-43 s or the time at which the size of the universe was roughly the Planck length (the time it takes light to travel the Planck length; G h bar / c⁵)^1/2 where G is Newton's constant of gravitation, h bar is Planck's constant, and c is the speed of light

radiation era 10 s after Big Bang The Big Bang era when the temperature had dropped to 10⁹K and the rate of electron-positron pair annihilation exceeded the rate of their production, leaving radiation the dominant constituent of the universe. nucleosynthetic era world point matter era 10¹² s 10⁹K

Subject	has start time	has definition	is preceded by	has density	has synonym	is followed by	has duration	has temperature
Big bang crossover effect	10¹² s	The epoch during the radiation era when the universe switched from being radiation-dominated to being matter-dominated.			world point
hadron era	10^-43 s after Big Bang	The Big Bang era during which quantum and general-relativistic effects are expected to modify each other in an unknown way.	Planck era	ρ = 10⁹³ g cm^-3	hadron barrier	lepton era	10^-5 s
inflation era	10^-35 s	Big Bang era in which the infant universe went through a brief period of extremely rapid (exponential) expansion, after which it settled back into the more leisurely rate of expansion of the standard model. The period of rapid expansion began and ended when the universe was still much less than a second old, yet it provides a physical explanation for the flatness and horizon puzzles. The inflationary universe model also suggests that the universe is vastly larger than the portion of it that is visible to us. (See exponential expansion.)			world point
lepton era	10^-5 s after Big Bang	The Big Bang era when the temperature had dropped to about 10¹² K and when the Universe consisted mainly of leptons and photons. It lasted until the temperature fell below 10¹⁰ K. At this stage, the characteristic photon energy fell below the rest mass energy of an electron, and the abundance of electron-positron pairs fell by many orders of magnitude. Only one electron survived for every 10⁸ photons. The universe was subsequently radiation-dominated (substantial numbers of neutrinos were also present, but they did not interact directly with the matter or the radiation).	hadron era		world point	nucleosynthetic era	1 s	10¹⁰ K to 10¹² K
matter era	10¹² s	The release of photons from constant collisions with massive particles as the universe expanded and its matter density diminished. See decoupling.	radiation era		decoupling era		> 10¹⁰ years	3 K to 3000 K
nucleosynthetic era	1 s after the Big Bang	The Big Bang era when neutrons were produced and helium and deuterium were synthesized. At t = 200 sec, nucleosynthesis began rather abruptly and virtually all deuterium was synthesized to helium.	lepton era		world point	radiation era	1000 s
Planck era	0 s after Big Bang	The Big Bang era, prior to which Einstein's theory of gravitation breaks down and a quantized theory of gravity is needed. Density was so high that gravitational force acted as strongly as the other fundamental forces on the sub-atomic scale.	Big Bang		world point	hadron era, inflation era	10^-43 s or the time at which the size of the universe was roughly the Planck length (the time it takes light to travel the Planck length; G h bar / c⁵)^1/2 where G is Newton's constant of gravitation, h bar is Planck's constant, and c is the speed of light
radiation era	10 s after Big Bang	The Big Bang era when the temperature had dropped to 10⁹K and the rate of electron-positron pair annihilation exceeded the rate of their production, leaving radiation the dominant constituent of the universe.	nucleosynthetic era		world point	matter era	10¹² s	10⁹K

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