Our nose is older than our feet

Einstein’s relativity opened a new chapter in physics from his first notes in a treatise on the electrodynamics of light. Special relativity already raised a point that emphatically separates the new physics from traditional Newtonian physics, and that is the non-absolute conception of space and time.

Already in special relativity we find that at higher speeds time passes more slowly for us than if we were at rest. Thus, with two twins, one an astronaut and the other a civilian, the astronaut would be younger than his brother (of course, by nanoseconds). But with general relativity, exposure to gravitational fields produces the same effect. The greater the gravitational field, the slower time advances.

A rather peculiar case is that the cells in our nose age faster than the cells in our feet. We admitted this in theory and assumed it to be totally impractical, but this experiment has already been performed with ultra-precise clocks separated by a small vertical displacement.

References

1. Superaccurate Clocks Confirm Your Hair Is Aging Faster Than Your Toenails. Published on September 23, 2010. Last accessed on July 12, 2017.