In this post, we will do a brief history lesson on the term natural philosophy and the branches of sciences that sprang from it. From there, we will look more closely at the world of physics
Natural philosophy was a catch-all term for the study of nature. Some of the fields associated with natural philosophy include biology, astronomy, and even medicine. With time, as knowledge grew, various subjects began to be spun off from natural philosophy into their own separate area of expertise.
For example, the subjects under natural philosophy have been divided into the natural sciences such as zoology and botany, and the physical sciences such as chemistry and physics.
The term physics comes from the Greek word “phusis,” which means nature. Therefore, physics is the study of nature or reality because nature is what many people consider to be real. Physics, in particular, has been further divided into classical and modern physics.
Classical physics covers the topics and discoveries of physics from the Renaissance until the end of the 19th century. As such, classical physics covers what the average person encounters in their day to day life and can be understood intuitively. The explanations that classical physics provide must fall under the following assumptions…
- Matter must move at a speed less than 1% of the speed of light or about 3,000,000 meters per second.
- The objects dealt with must be large enough to see with the naked eye.
- Only weak gravity, like earth’s, can be involved.
Again, this is where life is for most of us. Classical physics must be understood before trying to understand modern physics. Modern physics throws out the three assumptions above with two main contributions, which are the theory of relativity and quantum mechanics.
Einstein’s theory of relativity states that the measured length of an object traveling at high speeds is shorter than an object at rest. By high speeds, we are talking about faster than 1% of the speed of light (this is breaking the first assumption mentioned above). For example, time, which is a measure of change, moves slower for an object traveling above 1% of the speed of light compared to an object at rest. This means that if you could travel this fast, you would age slower than someone at rest. Gravity can also affect time as satellites in space have to readjust their clocks to sync with the earth. This is called dilation.
Quantum mechanics deals with the very small, which is breaking the second assumption. We are talking about objects on the atomic and subatomic levels. The rules at this level are often bizarre because these tiny particles can travel almost the speed of light, thus breaking assumption 1. As such, this area of physics has its own distinct rules.
Natural philosophy is perhaps a term that many people are not familiar with. This is because the term has been chopped up and divided into many different branches of science. Within the sciences, even physics has several subdivisions as people continue to learn more about the world around them.