What about time?

If you want to live 100 years, understanding time is an important and relevant task. Discover Magazine published an article about Ten Things Everyone Should Know About Time that might interest you, specially the those points:

9. Aging can be reversed. [...] Reversing the arrow of time for living organisms is a technological challenge, not a physical impossibility. [...]

10. A lifespan is a billion heartbeats. [...] Larger animals live longer; but they also metabolize slower, as manifested in slower heart rates. These effects cancel out, so that animals from shrews to blue whales have lifespans with just about equal number of heartbeats — about one and a half billion, if you simply must be precise. [...]

If you got interested, there are more interesting videos and articles on the Discover Magazine Time category, like this one: