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Thesis Title:



Aberration Effect Thought Experiment


T. Tsujioka

Aberration Effect
Logical Thought Experiment


This thesis is for those who only admit the following thought experiment and logic --- treating light as EM (electromagnetic) waves.

Consider the situation such that Observer A and B both see star light, coming from a star far away in the distance. Observer A is stationary to the star, a distant light source. Suppose that Observer B in a moving frame (e.g., a fast spaceship) now crosses the stellar light as in Fig.1(a). The moving Observer B inside sees the light ray, coming through the window and going out through the opposite window, shift as indicated in Fig.1(b). Since the light ray comes in from one window and goes out from the opposite window to the outside in the same time span as that of the laser ray inside, Observer B cannot but conclude that the passage of the light ray is longer than the reference length that he has set up via the laser ray parallel to the incoming stellar light at the incept. In other words, the speed of light coming from an external source observed inside the moving frame is observed faster than that of the laser ray emitted inside of the spaceship. Inside of the spaceship in which Observer B resides, he must tilt the telescope (by ; tan = v/c) in order to catch the stellar light due to the movement of the frame as in the Bradleyfs observational fact. (Annual Stellar Aberration in 1727; only about 20.5hobserved on the Earth, of which orbital speed is 0.01% of c.)

1(b) Moving observer sees a shift










1(a) Observer Afs standpoint

Fig. 1 Simple Thought Experiment of Aberration Shift

This phenomenon tells that the source of waves is seen in a shifted direction by the observer in a moving frame. Moreover, the number of waves must be the same since the frame of Observer B just crosses the light ray, the length ought to contain the same number of waves. Thus, it follows that the frequency is the same, and the wavelength becomes elongated, or, as it were, waves are observed esliding.f Like the Doppler effect, I call Aberration Effect, which is to hold for waves in general. (General characteristics of waves are: 1. the propagation speed of waves through a given medium is constant, and 2. waves, once emitted from the source, propagate independently of the source.) What makes these effects is the energy difference between the frame of light source and the observer.


Copyright by T. Tsujioka,
who is entirely responsible for the content.

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