Built on Facts

Apollo 11 launch
July, 1969

Today is the 4th of July, the day the United States of America celebrates its independence. It’s a unique and beautiful country, and I’m glad I had the good fortune to be part of it.

For much of its history the country was a bit of a scientific backwater, contributing modestly to the progress of human knowledge but rarely in groundbreaking ways. The first few decades of the Nobel Prize in physics include only a few Americans. The Second World War shattered the preexisting system, and due largely to massive research efforts during the war and the emigration of scientists from Europe to America, physics in the US began its rise. The post-war economic boom and the looming threat of Soviet scientific advances kept both interest and funding for physics at a fever pitch.

The results began building on each other and the Nobel Prizes kept piling up. Feynman, Gell-Mann, Weinberg, Lamb, Mather and Smoot, Bardeen, Cooper, and Schrieffer… Today the US and its unparalleled university system keeps growing its own brilliant scientists while also serving as a place for scientists and graduate students of every nationality to study and research their own fields.

The world is a big place, and love of country in no way implies lack of respect and admiration for the others. So on this, my country’s birthday, I think it’s worth looking back with pride and hopefulness that the land of the free and the home of the brave will always continue to be thus.

Might I suggest two ways to celebrate the 4th with physics? If it’s legal in your area, the dry ice bomb is a very cool, very cheap, and VERY loud demonstration of both phase transitions, gas pressure, and the propagation of compression waves through air. Be careful! It’s less dangerous than many seemingly mundane fireworks, but there’s still substantial risk involved. A less dangerous and less noisy but prettier effect involves powdered non-dairy creamer. Get a big bottle (about $2 at Wal-Mart or similar), gently shake a thin cloud of the powder over a flame, and enjoy the fireball. Done outside away from flammable things, this is actually a lot safer than it looks. In my experience at worst you’ll singe arm hair, but I make no guarantees and gently remind you that you are responsible for your own safety and well being. It’s an interesting exercise in chemical thermodynamics, and the vast difference a large surface area to volume ratio can make in the behavior of a substance. Here’s a friend of mine (I hope he doesn’t mind!) doing this trick a few years ago. Don’t worry, the fireball only lasts about one second.

Have a happy 4th!