Mil gracias a todos
Many thanks to all
Merci beaucoup à tous
Grazie mille à tutti
谢谢大家
شكرا لكم جميعا
תודה לכולכם
Obrigado a todos
Vielen Dank euch allen
Tack alla
Хвала свима
Gràcies a tots
In 1948, Fermi uncovered the origins of Cosmic Ray Acceleration. Today, the concept of Fermi acceleration is foundational in the study of cosmic ray physics. Initially, it was proposed that cosmic rays scattered off moving magnetic clouds. The underlying calculations for this theory are straightforward. Through his analysis, Fermi identified a power law spectrum. The observed power of -2.9 is connected to the mean free path of the scatters, which is determined to be 2 light years — a plausible distance.
Fermi then posed an intriguing question: "Why aren't there any electrons?" He demonstrated that in a typical galactic magnetic field measuring 10 gauss, the energy loss rate due to radiation for electrons with energy more than or equal to 250 MeV exceeds the energy gain rate. However, for protons, this energy threshold is at an astounding 3 x 10²¹ eV. This note was written in December 4, 1948.
How many π digits do we need?
3.1415 ➡️ design the finest engines
3.1415926535 ➡️ obtain the circumference of the Earth within a fraction of an inch
3.1415926535897932384626433832795028842 ➡️ measure the radius of the universe to an accuracy equal to the size of a hydrogen atom
Just walked past about 10,000+ ppl on the streets of #NYC on a Monday morning. NONE of them had a SMILE on their faces.. 🤯.
.I think I now know the SECRET to LIFE.
Quote from @geoffreyhinton :
"There are very few examples of a more intelligent thing being controlled by a less intelligent thing."
Have you looked at your:
Head of state?
Elected representative?
Pointy-haired boss?
Pastor/rabbi/imam/guru?
PhD advisor?
Cat?