# And it still means the same thing

The ” & ” sign was created by putting the letters E and t together. Et in Latin was the word for ‘and’.

(The Great Courses – Writing and Civilization:From Ancient Worlds to Modernity)

# The REAL equation

The most famous equation in physics is probably E = m times c squared.That is true for a stationary objects. The full equation is really                                                                                                          E squared = (p times (c squared) squared) times (m times c squared) squared) where p is momentum. When an object isn’t moving then momentum is zero and you get the abbreviated and more famous equation.

(The Great Courses – The Theory of Everything)

# You are mostly potential energy

The mass of every person can be calculated by adding up the mass of all the protons and neutrons from each atom in us. HOWEVER…protons and neutrons are made up of quarks and when you add up the mass of the quarks they are only about 2% the mass of an atom. Quarks move at incredible speeds inside a very small area in a proton and neutron so they store a great deal of potential energy and because of the equivalence of energy and mass that is where the extra mass is located.

(The Great Courses – The Theory of Everything: The Quest to Explain All Reality)