There are biological, psychological, and social differences between a 25 year old and a 45 year old, none of which are in favor of the 45 year old. For example

There are biological, psychological, and social differences between a 25 year old and a 45 year old, none of which are in favor of the 45 year old. For example, the highest prize in Mathematics is the Fields medal, awarded every 4 years to the most outstanding mathematician under 40. Only once was there a problem with the age limit as all the important work in mathematics is done by young minds, anyway. The almost exception, by the way, was 41.