Common Elementary Particles
Several estimates imply that practically all the matter, when measured by mass, in the visible universe (not including dark matter) is in the protons of hydrogen atoms, and that roughly 1080 protons exist in the visible universe (Eddington number), and roughly 1080 atoms exist in the visible universe. Each proton is, in turn, composed of 3 elementary particles: two up quarks and one down quark. Neutrons and other particles heavier than protons, as well as helium and other atoms with more than one proton, are so rare that their total mass in the visible universe is much less than the total mass of protons in hydrogen atoms. Lighter particles of matter, although equal (electrons) or vastly more (neutrinos) numerous than protons, are so much lighter than protons, that their total mass in the visible universe is again much less than the total mass of all protons.
Some estimates imply that practically all the matter, when measured by numbers of particles, in the visible universe (not including dark matter) is in the form of neutrinos, and that roughly 1086 elementary particles of matter exist in the visible universe, mostly neutrinos. Some estimates imply that roughly 1097 elementary particles exist in the visible universe (not including dark matter), mostly photons, gravitons, and other massless force carriers.
Read more about this topic: Elementary Particle
Famous quotes containing the words elementary particles, common, elementary and/or particles:
“Listen. We converse as we live—by repeating, by combining and recombining a few elements over and over again just as nature does when of elementary particles it builds a world.”
—William Gass (b. 1924)
“A man of rare common sense and directness of speech, as of action; a transcendentalist above all, a man of ideas and principles,Mthat was what distinguished him.”
—Henry David Thoreau (1817–1862)
“Listen. We converse as we live—by repeating, by combining and recombining a few elements over and over again just as nature does when of elementary particles it builds a world.”
—William Gass (b. 1924)
“The atoms of Democritus
And Newton’s particles of light
Are sands upon the Red Sea shore,
Where Israel’s tents do shine so bright.”
—William Blake (1757–1827)