Search results
Results from the WOW.Com Content Network
This imbalance has to be exceptionally small, on the order of 1 in every 1 630 000 000 (≈ 2 × 10 9) particles a small fraction of a second after the Big Bang. [4] After most of the matter and antimatter was annihilated, what remained was all the baryonic matter in the current universe, along with a much greater number of bosons.
In physical cosmology, the baryon asymmetry problem, also known as the matter asymmetry problem or the matter–antimatter asymmetry problem, [1] [2] is the observed imbalance in baryonic matter (the type of matter experienced in everyday life) and antibaryonic matter in the observable universe.
The local geometry of the universe is determined by whether the relative density Ω is less than, equal to or greater than 1. From top to bottom: a spherical universe with greater than critical density (Ω>1, k>0); a hyperbolic, underdense universe (Ω<1, k<0); and a flat universe with exactly the critical density (Ω=1, k=0).
All the particles that make up the matter around us, such electrons and protons, have antimatter versions which are nearly identical, but with mirrored properties such as the opposite electric charge.
The universe, as a whole, seems to have a nonzero positive baryon number density – that is, there is more matter than antimatter. Since it is assumed in cosmology that the particles we see were created using the same physics we measure today, it would normally be expected that the overall baryon number should be zero, as matter and antimatter ...
Under current theory, the Big Bang explosion that initiated the universe should have produced equal amounts of matter and antimatter. This, however, does not seem to be the case.
[1] The lepton and baryon asymmetries affect the much better understood Big Bang nucleosynthesis at later times, during which light atomic nuclei began to form. Successful synthesis of the light elements requires that there be an imbalance in the number of baryons and antibaryons to one part in a billion when the universe is a few minutes old. [2]
Some large black holes in the universe are predicted to continue to grow up to perhaps 10 14 M ☉ during the collapse of superclusters of galaxies. Even these would evaporate over a timescale of up to 10 106 years. [17] After that time, the universe enters the so-called Dark Era and is expected to consist chiefly of a dilute gas of photons and ...