The time is 10^-43 seconds. All the energy in the universe was packed into a tiny point where it explodes out. The four forces, gravity, nuclear strong force, nuclear weak force, and electromagnetic force, were all combined into one super force that existed only for a moment to hold the universe together.
At the time of the explosion, the universe expanded at a factor of 10^78 in fractions of a second. Once the universe expanded a bit and cooled down, the gravity force was the first to separate from the three other forces. The nuclear strong force was the second to separate from the other two remaining forces.
Expansion
Theories say that the reason why the universe could expand so fast in mere fractions of a second was. When the initial expansion happened, the universe was expanding much faster than the speed of light. We know that nothing can travel faster than the speed of light though so how did the expansion of the universe travel faster than the speed of light?
The law that nothing can travel faster than the speed of light only applies to the movement of objects through space. The rate that space expands has no limit to its speed since space expanding is just the fabric of space time stretching, hence why the universe could travel faster than the speed of light at its initial expansion. If you want to learn more then contact me here
table
Time
Name
Temperature
What happened
10^-44s
Big Bang
10^32°C
Plank Temperature
10^-43s
Planck Time
10^15°C
The Universe is Created
10^-35s
Inflation
10^27°C
Universe Expands
10^-6s
Taking Shape
10^13°C
Inflation Slows
1s
Formation
10^8°C
Neutrinos, Protons, Quarks
3 Mineuts
Nucleosynthesis
800m°C
P+ & N form helium
After The Big Bang
After the events of the Big Bang, the universe cooled down and entered its dark ages. 300 million years later the first stars began to form. It was also around this time where there were super massive black holes. With all of the matter floating around in space it was practically a feeding ground for black holes to become massive.
Stars at the beginning of the universe were massive, because of all the matter floating around it would clump up and create super giant stars. It would take 2 billion years for galaxies to begin forming. Most hypergiant stars have gone supernova since the matter isn't as spread out far more than it used to be, along with their lifespan being relatively short.
Summary
This is the timeline in order again but with more descriptive text.
Big Bang: The universe is a singularity and has infinite temperature. Due to quantum fluctuations the singularity explodes out and expands to create the universe we know today.
Planck Time: The universe is 10^-44 seconds old. The universe at the time was 10^-33 cm in length which is the limit of how small you can get.
Inflation: The universe expanded so fast that it created a vacuum of energy that expanded the fabric of space by a factor of 10^78 in a fraction of a second.
Formation: The universe is 1 second old, protons and electrons are forming. The temperature was around 10^8°C and was cooling down at a rapid rate.
Nucleosynthesis: The universe has cooled down to the point where protons and nutrons combine to form hydrogen and helium with a very small chance of producing lithium (1 in 10,000,000,000 atoms).
Theories
Here are some of the most common theories that you will find about the Big Bang and how the universe might end.
Big Freeze: The universe will end with no light to keep it warm, expanding forever with emptiness.
Big Crunch: The universe reverses its expansion and begins to decrease in size causing a new Big Bang.
Big Rip: The expansion of the universe will rip apart all the matter in the universe as the universe expands.
Cold Big Bang: The universe didn't start super hot, but rather at absolute zero. This was canceled when the CMBR was discovered