Albert Einstein developed the two parts of the theory of relativity between 1905 and 1915.
Click on image for full size
Courtesy of Tracey Keifer. Emilio Segre Visual Archives. American Institute of Physics.
The Theory of Relativity
Albert Einstein was one of the most famous scientists of all time. Einstein thought up one of the most famous scientific theories ever. That is the theory of relativity.
The theory of relativity has two parts. The first part is the special theory of relativity. Einstein published the special theory of relativity in 1905. The second part is the general theory of relativity. Einstein came up with the general theory between the years of 1907 through 1915.
The two parts of the theory of relativity have very new, different, and strange things to say about the Universe.
The theory of special relativity says that strange things happen when objects move very, very fast. Light moves incredibly fast, around 300,000 kilometers per second (about 186,000 miles per second). If objects move almost as fast as light, strange things begin to happen. What kinds of strange things? Time slows down, the length of an object becomes shorter, and the mass of the moving object gets larger. If two people pass each other moving very fast, they may not agree that two events happened at the same time. Have you ever heard of Einstein's famous equation, E = mc2 ? That equation is also part of the theory of relativity. The equation says that it is possible to turn matter (the "m" in the equation) into energy (the "E" in the equation).
The second part of the theory of relativity is the general theory of relativity. It says that the "shape" of space can be curved near large objects that have a lot of gravity. Even rays of light curve when they pass near a massive object. That is why black holes can "suck up" light that passes close to them.
Shop Windows to the Universe Science Store!
Our online store
includes issues of NESTA's quarterly journal, The Earth Scientist
, full of classroom activities on different topics in Earth and space science, as well as books
on science education!
You might also be interested in:
Scientists use the word theory differently than nonscientists. "It’s just a theory," you hear people say. When speaking casually, people often use the word "theory" to mean a "guess" or a "feeling". In...more
Some ideas are used in many, many places throughout science. We have grouped these "starting points for science" into three clusters: space, time, and matter. "Space" is the word we use for everything...more
If there are other planets in the Universe that are like Earth, then they might be places where life could survive. However, the search for planets like Earth is not easy. Most of the planets found outside...more
Radiation comes in two basic types: electromagnetic radiation transmitted by photons, and particle radiation consisting of electrons, protons, alpha particles, and so forth. Electromagnetic radiation,...more
Carbon-14 dating (also called "radiocarbon dating") is used to determine the age of materials that contain carbon that was originally in living things. It is often used in archeology and some...more
The force of magnetism causes material to point along the direction the magnetic force points. As shown in the diagram to the left, the force of magnetism is illustrated by lines, which represent the force....more
The Earth is a good example of a planetary dipole, where the lines of force point in a direction out of the South (magnetic) Pole and into the North (magnetic) Pole. Planets can also show evidence of quadrupoles...more