How The Life Begin

Planck epoch Times shorter than 10 −43  seconds ( Planck time ) Main article:  Planck epoch The  Planck epoch  is an era in traditional (non-inflationary)  Big Bang cosmology immediately after the event which began our known universe. During this epoch, the temperature and average energies within the universe were so high that everyday subatomic particles could not form, and even the four fundamental forces that shape our universe— electromagnetism ,  gravitation ,  weak nuclear interaction , and  strong nuclear interaction —were combined and formed one fundamental force. Little is understood about physics at this temperature; different hypotheses propose different scenarios. Traditional big bang cosmology predicts a  gravitational singularity  before this time, but this theory relies on the theory of  general relativity , which is thought to break down for this epoch due to  quantum effects . In inflationary models of cosmology, times before the end of inflation (roughly 10 −32  

Further information:  Timeline of cosmological epochs ,  Timeline of natural history ,  Geologic time scale ,  Timeline of the evolutionary history of life , and  Timeline of the far future Further information:  Graphical timeline of the universe ,  Graphical timeline of the Big Bang ,  Graphical timeline from Big Bang to Heat Death , and  Graphical timeline of the Stelliferous Era Earliest stages of chronology shown below (before neutrino decoupling) are an active area of research and based on ideas which are still speculative and subject to modification as scientific knowledge improves. "Time" column is based on extrapolation of observed  metric expansion of space back in the past. For the earliest stages of chronology this extrapolation may be invalid. To give one example,  eternal inflation  theories propose that inflation lasts forever throughout most of the universe, making the notion of "N seconds since Big Bang" ill-defined. The radiation temperature re

The universe as it appears today. From 1 billion years, and for about 12.8 billions of years, the universe has looked much as it does today. It will continue to appear very similar for many billions of years into the future. The  thin disk  of  our galaxy  began to form at about 5 billion years (8.8 bn years ago),and the  solar system  formed at about 9.2 billion years (4.6 bn years ago), with the earliest traces of  life  on Earth emerging by about 10.3 billion years (3.5 bn years ago). From about 9.8 billion years of cosmic time,the slowing expansion of space gradually begins to accelerate under the influence of  dark energy , which may be a  scalar field  throughout our universe. The present-day universe is understood quite well, but beyond about 100 billion years of cosmic time (about 86 billion years in the future), uncertainties in current knowledge mean that we are less sure which path our universe will take.