Constancy of Speed of Light in Minkowski Diagram

This section provides a demonstration of constancy of speed of light using a Minkowski diagram.

The main assumption of the special theory of relativity is that the speed of light has the same value c measured in all inertial frames.

This assumption can be easily demonstrated by the Minkowski diagram. Let's follow a simple thought experiment described below:

Now let's assume that Amy's frame is moving at a speed of v=0.6*c:

So the speed of light is 1 (c) in both Bob's frame and Amy's frame.

Minkowski Diagram Showing Speed of Light
Minkowski Diagram Showing Speed of Light

Last update: 2014.

Table of Contents

 About This Book

 Introduction of Space

 Introducion of Frame of Reference

 Introducion of Time

 Introduction of Speed

 Newton's Laws of Motion

 Introduction of Special Relativity

 Time Dilation in Special Relativity

 Length Contraction in Special Relativity

 The Relativity of Simultaneity

 Introduction of Spacetime

Minkowski Spacetime and Diagrams

 What Is Minkowski Spacetime?

 Events Interval and Relations

 What Is Lorentz Transformation?

 What Is Minkowski Diagram?

Constancy of Speed of Light in Minkowski Diagram

 Time Dilation in Minkowski Diagram

 Length Contraction in Minkowski Diagram

 Relativity of Simultaneity in Minkowski Diagram

 Invariant Spacetime Interval in Minkowski Diagram

 Multiple Reference Frames in Minkowski Diagram

 References

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