Albert Einstein, along with Sir Isaac Newton, is generally regarded as the greatest physicist of all time. He played a major role in the development of modern physics, and his theories have changed the way we view and think about the universe. When people think of Einstein, they generally think of E = mc^2, probably the most famous equation ever written down. This equation is a result of one of his theories, the special theory of relativity.

The results of special relativity can be confusing and strange to someone who looks at the theory for the first time. We won't go into the development or derivation of the theory here, but rather introduce the main results of the theory and how they apply to a high energy physics experiment such as CDF.

Special relativity arises from two postulates. One of these postulates that Einstein assumed to be true in our universe is that light travels at one speed, the speed of light (186,000 miles per second!), which is a constant no matter where you measure the speed from. It is the ultimate speed limit for all the objects we see in our universe. This is different from what we would be lead to believe from Newton's theories of motion, where no limit is placed on the speed of an object. Why would Einstein think the speed of ligh t is the ultimate speed in the universe? What happens when ordinary matter gets close to the speed of light that prevents it from surpassing it?

It turns out strange things happen to objects as they move about space and time. The "biggies" are:

• the object's mass increases
• the object's length decreases
• time slows down for the object

As weird as these sound, we now know they're true! And some of the experimental evidence that these are real effects comes from Fermilab and experiments like CDF.

Quantum Theory >

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