The hot Big Bang occurred 13.8 billion years ago, and there’s no other possible answer consistent with what we know today.

So where did the antimatter go?
This question is one of the biggest mysteries of modern science, and the answer is unknown. Something happened in the earliest moments of the universe to make the antimatter disappear. From our best current measurements of the primordial radiation of the Big Bang (called the cosmic microwave background radiation, or CMB), something tilted the scales in favor of matter, with the ratio of for every three billion antimatter particles, there were three billion and one matter particles. The two sets of three billions cancelled and made the CMB, and the remaining tiny amount of matter went on to form the stars and galaxies that we see in our telescopes today. For this to happen, some physical process had to favor matter over antimatter.
While Einstein’s theory says that matter and antimatter should exist in exactly equal quantities, in 1964, researchers found that a class of subatomic particles called quarks slightly favor matter over antimatter. Quarks are found inside the protons and neutrons at the center of atoms. While this was an important observation, the differences between matter and antimatter quarks were too small to explain the dominance of matter we see in the universe.
There’s some irony in the fact that the darkest objects in the sky — black holes — can be responsible for some of the Universe’s brightest light. Simulations of the magnetic fields surrounding black holes and neutron stars have now provided new insights into their astonishing brilliance.
Astrophysicists from Columbia University in New York have developed a model that shows how electrons taking a cosmic roller coaster-ride through magnetic turbulence can generate surprisingly energetic waves of radiation.
Applied to the swirling chaos surrounding dense objects such as black holes, it helps to explain why we see them glow with a ferocity that so far defies explanation.
The current Lambda CDM model may explain a great deal about the evolution and the chronology of the events that occurred in our Universe but it doesn’t paint the complete picture.
We know of the cosmic inflation that happened followed by the Big Bang itself however how these two are coherently connected has so far defied all our attempts to explain.
During the inflationary period, within less than a trillionth of a second, our universe grew from an infinitesimal point to an octillion (that’s 1 followed by 27 zeroes) times in size, which was followed by a more conventional and gradual period of expansion, nevertheless violent by our standards, which we know as the Big Bang.
The universe is filled with billions of galaxies and trillions of stars, along with nearly uncountable numbers of planets, moons, asteroids, comets and clouds of dust and gas – all swirling in the vastness of space.
But if we zoom in, what are the building blocks of these celestial bodies, and where did they come from?
Hydrogen is the most common element found in the universe, followed by helium; together, they make up nearly all ordinary matter. But this accounts for only a tiny slice of the universe — about 5%. All the rest is made of stuff that can’t be seen and can only be detected indirectly. [From Big Bang to Present: Snapshots of Our Universe Through Time].