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...short years ago mathematical builders of the universe got along with two fundamental particles, the proton and the electron. The proton was the nucleus of the simplest atom, hydrogen. It had a charge of positive electricity and its mass was .0000000000000000000000166 gram. The electron, which in the hydrogen atom throbbed alone around the nuclear proton, had a negative charge matching the proton's positive charge and its mass was 1,847 times less than that of the other particle. The more complex atoms of other elements were constructed from various combinations of electrons and protons...

Author: /time Magazine | Title: Science: Symmetry | 4/5/1937 | See Source »

Then, in quick succession, the neutron was discovered by Chadwick in England and the positron by Anderson in California. The neutron was about as heavy as the proton but had no electric charge. The positron had the same mass as the electron but an opposite charge. Physicists then saw that if they could add to their collection a particle heavy like the proton but negatively charged, and a particle light like the electron but not charged at all like the neutron, they would have a neat array of pairs and triplets, as follows...

Author: /time Magazine | Title: Science: Symmetry | 4/5/1937 | See Source »

MASS CHARGE Plus Minus No Charge Heavy Proton (Negative Neutron proton?) Light Positron Electron (Neutrino...

Author: /time Magazine | Title: Science: Symmetry | 4/5/1937 | See Source »

...Dirac then proposed to construct a new universe out of the leftovers. He had noticed that another scientist of imagination, Sir Arthur Stanley Eddington, had arrived at theoretical values for certain constants, such as the quantity of matter in the universe (using the proton as a unit) and the ratio of the electric to the gravitational force between proton and electron. These two Eddington values worked out at 10 78 (10 multiplied by itself 77 times) and 10 39 . Although, as Dirac says, "Eddington's arguments are not always rigorous," they nevertheless gave him "the feeling that they...

Author: /time Magazine | Title: Science: Leftover Universe | 3/15/1937 | See Source »

...square of the universe's age would therefore be equal to Eddington's other figure, 10 78 . Armed with these two fine coincidences, Dirac next proposed to dispense with the giant numbers and simply say that the ratio of electrical to gravitational force between proton and electron equals t, the age of the universe, and the amount of universal matter equals t². But the universe is not getting any younger. Thus the values dependent on t and t² are not constants at all, but get bigger with the passage of time. The quantity of universal matter...

Author: /time Magazine | Title: Science: Leftover Universe | 3/15/1937 | See Source »

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