I’m fascinated by holograms. We see them all the time, these days, mostly on credit cards. A three dimensional image appears on a two-dimensional surface. As you turn the credit card in your hand, the little dove on the silvery stamp in the corner turns as though it were a real object in your hand, rather than a little picture of the bird. Some credit-card holograms are tiny depictions of the Earth.
The image is not a photograph. It is not, properly, even a picture. It is a reproduction of the way light from two different perspectives is “scattered” by the presence of the object, diffracted when the two light beams interact, and then perceived from a third perspective. If we change the third perspective by turning the hologram in our hand, our eye perceives the image changing as though the object was turning.
Scientists worked for decades to create useful holograms, starting with our growing knowledge of how the human eye perceives all images — both real and reproduced — applying new knowledge of the physics of radiation in the late 1940s, then exploiting the special qualities of lasers developed in the early 1960s. Our knowledge of the physics continued to improve and lasers got cheaper and more controllable over the next decades. In March of 1984, National Geographic Magazine ran a hologram of an eagle on its cover, “embossed” on the same sort of reflective surface used on credit-card holograms, much larger and in very high resolution. Hundreds of thousands of people were suddenly holding in their hands the first hologram they had ever seen, turning it this way and that, watching the eagle turn as though it were an object rather than an image.
It was poetic that the magazine that first carried modern photographic technology into some of the world’s most remote regions would also bring holographic technology — a brand new sort of image — into the mainstream for the first time.
A photograph reproduces an image from a single perspective, the camera’s lens. The camera records the light bouncing off the scene. A hologram records the light field surrounding an object. When we look at a holographic reproduction our eyes are exploring that light field.
Every minute point in the light field contains as much information about the object as a photograph. The scene could be reproduced from each minute point of light, like a tiny photo. Each tiny photo is subtly different because it was recorded at a different point in the light field.
When our eyes look at a scene, they perceive the light bouncing off each minute detail of the objects in that scene. As we move, or the objects move, our eyes catch tiny variations in each minute detail. Those variations give us our three-dimensional perception of objects and motion. We can admire a beautiful mountain range, ski through a grove of aspen or drive a car.
The light field recorded in a hologram provides our eyes with the same kind of information. It presents the scene from thousands or millions of minutely different perspectives. Our eyes read those myriad perspectives and perceive three-dimensional objects. As we look at the hologram from different angles, our eyes perceive the same changes in the light field they would perceive if we were moving around the original scene.
My conviction that we need a better vision for our future led me to consider the way we form images, which led me to holograms. Humanity’s perception of its present world and its vision for its future are formed from billions of individual perspectives. Each individual human being possesses a unique vision, a single point in the light field. Each perspective records the person’s place in space and time. Each point of light forms a complete image, a complete vision for the future. When we reproduce the light field projected by those billions of unique visions, we get a three-dimensional picture of humanity’s combined vision. Effectively, we can’t perceive the future in three dimensions without taking into account the entire light field.
So if we are to create a new vision for our future, we need to illuminate it from more than one perspective. Our vision needs to exist in an infinitely complex field of perspectives.
We’re discouraged by the scale of this challenge.
But maybe if we approach the problem as a physicist would, it will prove more soluble than we expect.
No one could build a hologram by hand, recording each minute point with its tiny variations across the whole light field. But by shining the right kind of light on the scene from a couple of different perspectives and then perceiving it from precisely the right position, we may be able to form an image that appears sharp and real from any of the infinite number of perspectives from which it might be viewed.
For the purposes of illuminating a vision, statements of fact are unreliable. Facts change with perspective. A dollar is worth a dollar, yet that dollar is much more valuable in the hand of a child in a Tijuana slum than it is in the shops along Rodeo Drive in Beverly Hills. The 10-pound dumbbell that’s trivial to us when we’re 25 years old presents a formidable physical challenge at 85. If the value of a dollar or the burden of 10 pounds of steel vary dramatically with perspective, then less substantial, more subjective facts must be even less reliable. Our estimations of deforestation, desertification, climate change and acid rain vary wildly with our perspective.
So if we are to help billions of people illuminate a new vision, facts are not necessarily the most useful sources of light. For these purposes, simple queries might be more utilitarian.
I’m suggesting four questions that may serve as sources of light. Shone on our endeavors, perceived from billions of unique perspectives, they might serve to illuminate a vision.
Is it fair?
Is it repeatable?
Is it beautiful?
Does it create abundance?
Photo by Bryan Welch