Question from kid in 4th grade at Wyeville Elementary School

What is meant by the sixth dimension and how that fit into Black Holes?

ANSWER:

            Modern science is composed of two theories that are seemingly incompatible. One theory, general relativity, championed by Albert Einstein, explains how big things work, like planets and galaxies. The other theory, quantum mechanics, successfully explains things that are very small, like atoms and subatomic particles. And there is a lot of  incompatibly between these two theories.

            Einstein’s Theory of Relativity is really an extension of Isaac Newton’s concept of how the world works. All the laws of nature, mass, energy, and motion that you and I experience in everyday life are explained by Newton’s Three Laws. Albert Einstein extended Newton’s Laws to things that move very fast, like close to the speed of light.            

            Einstein tried to find a single theory that would embrace all of nature’s laws; a single theory that would marry relativity, used on the astronomical level,  to quantum mechanics, used at the atomic level. Einstein spent 40 years trying, but was not successful. Discovering a single unifying theory, a single master equation, is today’s Holy Grail of science.

            Now, the talk is all about something called  “string theory”, sometimes referred as the “Theory of Everything”. These scientists are discussing eleven dimensions and parallel universes. Strings are tiny bits of energy, vibrating like strings on a guitar.

            The first three dimensions are length, width, and depth. The fourth dimension is space, the fifth dimension is time. Six dimensional space has six degrees of freedom, and uses six coordinates or points to specify a location in space. Three of these dimensions are translational along an x, y, and z coordinates and the other three are sets of rotations.

            There does happen to be a real life example of six dimensions. NASA has a spacesuit that an astronaut could fit into, and can operate outside the Space Shuttle.  This  MMU (Manned Maneuvering Unit) allowed an astronaut to move in all axis or degrees of freedom;  side to side, right to left, up and down, pitch, roll, and yaw. The astronaut is said to move in all six dimensions.

            No one really knows how many dimensions make up the universe. It is a very exciting field of research. Black holes may provide clues to aid astronomers in determining the number of dimensions that make up the universe. The extremely strong gravitational field of a black hole complicates the issue. Inside a black hole, time becomes a dimension, giving rise to the four dimensional term “space-time”.

            PBS has a three-part series called “The Elegant Universe” with author and physicist Brian Greene.  PBS also has four-part series called “The Fabric of the Cosmos” that is excellent and does a nice job of trying to explain some of these obtuse and very complex ideas.

            We’re never really sure what will be the outcome of all this research. In the 1920’s, there was lots of speculation on the value of quantum mechanics. “What good is it?” was a frequent question. It turns out that all modern electronics, smart phones,  flat screen television, GPS, lasers, microcircuits, LED’s, all came about because of the research used quantum theory.