"How To Prove Einstein's Relativity In The Palm Of Your Hand"

From Forbes:

Cosmic rays, which are ultra-high energy particles originating from all over the Universe, strike protons in the upper 

atmosphere and produce showers of new particles. The fast-moving charged particles also emit light due to Cherenkov 

radiation as they move faster than the speed of light in Earth's atmosphere, and produce secondary particles that can be detected here on Earth.Simon 

Swordy (U. Chicago), NASA

When you hold out your palm and point it towards the sky, what is it that's interacting with your hand? You might correctly surmise that there are ions, electrons and molecules all colliding with your hand, as the atmosphere is simply unavoidable here on Earth. You might also remember that photons, or particles of light, must be striking you, too.

But there's something more striking your hand that, without relativity, simply wouldn't be possible. Every second, approximately one muon — the unstable, heavy cousin of the electron — passes through your outstretched palm. These muons are made in the upper atmosphere, created by cosmic rays. With a mean lifetime of 2.2 microseconds, you might think the ~100+ km journey to your hand would be impossible. Yet relativity makes it so, and the palm of your hand can prove it. Here's how.

While cosmic ray showers are common from high-energy particles, 

it's mostly the muons which make it down to Earth's surface, where t

hey are detectable with the right setup.

Alberto Izquierdo; courtesy of Francisco Barradas Solas

....MUCH MORE

See also Blake, William:

"To see a World in a Grain of Sand

And a Heaven in a Wild Flower 

Hold Infinity in the palm of your hand 

And Eternity in an hour..."

—Auguries of Innocence, 1803