The sequence of events in the history of the Universe is nicely summarized in a web site at "Talk Origins". Note that in the chart at this site an expression such as 5x10^4 means five time ten to the fourth power seconds, which is 5000 seconds, or 1x10^-43 means one times ten to the negative forty-third power which is: 1/10,000,000,000,000,000,000,000,000,000,000,000,000,000,000 of a second!!
The 1x10^-43 is "scientific notation" and is much shorter than the former fraction!

Go back to Lecture 7