For the Love of Physics: From the End of the Rainbow to the Edge of Time—A Journey Through the Wonders of Physics

a clue what that is either. The bottom line is that we’re ignorant about 96 percent of the mass/energy in our universe.

Electrons are so small that some say they have no effective size—they’re less than a thousand-trillionth of a centimeter across—and

Mercury orbits the Sun in just eighty-eight days,

Mercury orbits the Sun in just eighty-eight days,

the three isotopes of hydrogen, only one, tritium, is radioactive—it decays into a stable isotope of helium.

a clue what that is either. The bottom line is that we’re ignorant about 96 percent of the mass/energy in our universe.

Electrons are so small that some say they have no effective size—they’re less than a thousand-trillionth of a centimeter across—and

the three isotopes of hydrogen, only one, tritium, is radioactive—it decays into a stable isotope of helium.