Atomic Theory History Question

Did the Greeks discover atoms?

Democritus lived about two hundred years before Aristotle and Plato, and is often credited with originating the concept of the atom. He was a philosopher, and his idea was to try to explain why different materials had different properties, such as why are liquids flexible and solids less flexible. We know now that the atoms, for example in ice, water, and steam are all made of the same kinds of atoms. Many Greeks of the time thought that the highest form of research was thinking about things, because the mind and ideas are superior to the world and the senses, or something like that. The word "atom" means indivisible, and in that sense, the Greeks were sort of correct. I would argue they really had no idea what atoms really are.

John Dalton, in the early 1800's, more than 2,000 years after Aristotle, formulated the first modern version of atomic theory, and by then he had enough scientific data to actually do a pretty good job of describing an atom as we now understand it. Still, there was no direct evidence to prove the existence of atoms, and Dalton's atomic model was primitive by modern standards.

It wasn't until 1905 that Albert Einstein published a paper that actually proved the atomic theory, and even since then, the model of the atom has been corrected and improved many times. Murray Gell-Mann, a physicist who lives in Santa Fe, won the Nobel Prize in Physics for his research into the inner structure of protons and neutrons.

Manhattan Project questions from a high school student.

          I was tempted to send you off to do your own research, but after poking around a little, I realize that your questions fall into some difficult holes in the published record.

1.  How many employees worked in Los Alamos and what did most do?

There were several thousand people living in Los Alamos at the end of the war. Most of them were support staff; technicians, clerical workers, the army, etc. I haven't come across an actual figure yet. According to Wikipedia.org, there were 130,000 people working in the entire Manhattan Engineering District across the country by that time.

2.  How much later after the bomb was dropped did the world find out about Los Alamos?

Little Boy was dropped on Hiroshima on Aug 6, 1945. Chapter 12 of the Smyth Report (Atomicarchive.com), released to the public on August 12, 1945, describes Los Alamos' work in developing the atomic bombs. OTOH, the city and lab were still highly secret for many years. I have a USGS map of Bandelier National Monument  in my office dated 1953 that shows White Rock, NM. but not a trace of Los Alamos.

3.  Where was most of the uranium found for the bomb?

Much of the Manhattan Project uranium came from pitchblende mined in the Belgian Congo (the Democratic Republic of Congo today.) I believe most of the uranium used at that time came from Africa. The uranium mining industry in America came later.

Good luck with your project!