The Dynamic Frequency Ratnadeep Das Choudhury

Lepton Epoch is the 7th phase according to the Chronology of the Universe. It’s the very next step of Hadron Epoch. Lepton Epoch was started 1 second after Big Bang and lasted up to 3 minutes after the big bang.

If you haven’t read my article on Hadron Epoch then, I suggest you to read that first as it will help you understand this article fully…..

After Hadron Epoch, majority of hadrons and anti-hadrons annihilated each other. So, during Lepton Epoch majority of the mass was dominated by Leptons.
Even during the start of this epoch, the lepton and anti-lepton were existed as pairs but after 10 seconds after the big bang the temperature was low enough to trigger the process of annihilation reactions between leptons and anti-leptons.

Soon, all of the anti-leptons were destroyed but a very small amount of leptons remained and those remaining leptons ultimately made our universe.  Just like in Hadron epoch, photons in Lepton epoch also collided to form electron-positron pairs.

Feynman Diagram Showing annihilation of positron and electron and production of photon in the process The Dynamic Frequency Ratnadeep Das Choudhury
Feynman Diagram Showing annihilation of positron and electron and production of a photon in the process

Leptons like tau, Muon which are otherwise known as third-generation leptons believed to exist along with its antiparticle twin for a few seconds during this epoch. Today, these particles exist for a few seconds as they quickly decay through weak force into electrons and positrons, neutrinos and anti-neutrinos which are lighter and more stable than those leptons.

For example, massive tau lepton decays into one down quark and one up antiquark as well as some other particles. But more about it in my future posts….

Lepton Epoch is followed by Nucleosynthesis phase. My upcoming blog will be on it…..

I have also written a crisped introduction on Leptons in my Introduction to Standard Model of Particle Physics post….so, if you want to know about them in detail then please to this post. More detailed posts about particles are coming soon on this website so, stay tuned to us and subscribe this website…..


To know basics of quantum world, astronomy and space exploration you can check out my book "Through the wormhole" on amazon kindle.

You can directly talk with me on Instagram
To meet more physics Enthusiasts please join our Facebook Page 
Also for latest updates of my posts join me on Twitter

Thanks for reading.....

See you next time!!!


                                                                      -Ratnadeep Das Choudhury
                                                      Founder and Writer of The Dynamic Frequency


0 Comments