Once upon a time, the earth was flat.
Ramesh Raskar, a researcher at MIT, has figured out how to almost freeze light particles. He has created an imaging system that has a “shutter speed” of less than two trillionths of a second. A light beam travels less than half a millimeter in that time. You can read about it in the New York Times here. Dr. Raskar is busy making time-lapse movies of light beams traveling through space.
Interestingly, this achievement is the result of an attempt to see around corners, by calculating backwards from light that escapes to an image of where it is coming from. This is looking back in time in a way similar to astronomers who look back in time on a grand scale when they gather data from electromagnetic energy that has been traveling since before an intelligent receptor was in place on earth.
The article ends with a quote from Dr. Raskar:
We’re still trying to get our heads around what this means…because no one has been able to see the world in this way before.
Our conception of the reality of our world is determined by the extent of our ability and need to perceive. Once upon a time, it was widely believed that the earth was flat. At the time it might as well have been, given the distances that any given individual could travel in a day. There was a time when most people didn’t wander more than a few miles from home for an entire life time. Why do you need a concept of a round world if that is all the distance anyone travels?
It was not until we began to navigate the seas in sufficient numbers that we had need for a concept of the world as round and ultimately came to broadly accept it as being so. It’s not that the roundness of the world was unknown to anyone. A few particularly astute individuals had figured it out. The signs were there. The math was not hard. There just wasn’t the need to know it as a people. For the needs of their daily lives it was adequate and, for the limited frame of reference, accurate to think of the world as flat. Life worked just fine with that concept.
Whenever anyone asks me to place unlimited trust in anything we know in the here and now, I remember that once upon a time the world was flat. There is no such thing as ultimate knowledge of the universe. Our ways of looking at it are constantly evolving, and more importantly, our ability and need to expand the horizons of our perception proceeds unabated. What passes for sure knowledge of how things work in the here and now is almost certain to appear naive many centuries from now. Our ways of seeing will constantly grow and we can’t begin to imagine what understandings we may have in a few thousand or even a few hundred years. Everything is open to question. Nothing can be said with absolute certainty until, and unless, our means of knowing and perceiving becomes god like. Until that time, we are left to deal with the world within the context that we know, and if we are wise, we do so with a healthy amount of humility.