There are all sorts of resonances around us, in the world, in our culture, and in our technology. A tidal resonance causes the 55 foot tides in the Bay of Fundy. Mechanical and acoustical resonances and their control are at the center of practically every musical instrument that ever existed. Even our voices and speech are based on controlling the resonances in our throat and mouth. Technology is also a heavy user of resonance. All clocks, radios, televisions, and gps navigating systems use electronic resonators at their very core. Doctors use magnetic resonance imaging or MRI to sense the resonances in atomic nuclei to map the insides of their patients. In spite of the great diversity of resonators, they all share many common properties. In this blog, we will delve into their various aspects. It is hoped that this will serve both the students and professionals who would like to understand more about resonators. I hope all will enjoy the animations.

For a list of all topics discussed, scroll down to the very bottom of the blog, or click here.

Origins of Newton's laws of motion

Non-mathematical introduction to relativity

Three types of waves: traveling waves, standing waves and rotating waves new

History of mechanical clocks with animations
Understanding a mechanical clock with animations
includes pendulum, balance wheel, and quartz clocks

Water waves, Fourier analysis



Friday, May 27, 2011

Understanding special relativity

All postings by author next - history of relativity


Understanding special relativity

1904 image of Albert Einstein
Fig. 1a. Albert Einstein (1879-1955), German/Swiss/American physicist. One of the great physicists of the twentieth century, started much of the current "modern physics", including relativity and quantum mechanics.
relativity is unnecessarily confusing to the average person
Fig. 1b. Albert Einstein's usage of "time" and "space" makes his theory of relativity confusing to the average person.

Preview of this article

Einstein's theory of special relativity has been an unquestionable success in accounting for the behavior of very rapidly moving objects. From its beginnings to explain the behavior of light, it has been expanded to cover anything to that is moving extremely rapidly. It is particularly central to the understanding of high energy subatomic particles such as those occurring in nuclear (radioactive) events.

This posting introduces the history of this theory and goes on to explain it using an approach suggested by John Bell. This approach uses an absolute reference frame to introduce relativistic effects as an alternative to the warping of space and time which the average person finds difficult to understand. While Einstein seemed to greatly dislike the use of an absolute metric, his theory does not rule it out and its use greatly aids the introduction to relativity. This approach also leaves open the possibility of an absolute metric in the minds of students, who may someday go on to invent new physics based it. Some thoughts about the meaning of an absolute metric are also explored.

This paper presents relativity at a non-mathematical level, stressing the history, phenomena, and philosophy of relativity. Some readers might also be interested in a set of postings of a subsequent article that delve into the mathematical side of the subject.

Direct link to a summary of this article


Contents of "Understanding special relativity"

  1. Preview
  2. Contents
  3. A brief history of relativity
  4. Thought experiments
    Fig. 1c. The decay sequence for radioactive neptunium. Einstein's theory of special relativity provided the basic background knowledge that led to the understanding of the complexities of nuclear physics.
  5. The confusing aspects of Einstein's approach
  6. Lorentz transforms as a pragmatic calculational tool
  7. Several applications of special relativity
  8. Summary
  9. General relativity
  10. What is space?
  11. Is ether dead?
  12. Progression of clocks at the National Institutes of Science and Technology
  13. Advantages of including Lorentz's approach in the teaching of relativity
  14. Links and references
  15. The mathematics of special relativity
All postings by author next - history of relativity