Dec 5, 2015 - Direction of Light is Affected by the Speed of its Source. 4. .... The implication of this possible alternative is beyond this inquiry. 05/12/2015. 8.
An effort in understanding Special Relativity (4)
An Inquiry Into the Speed of Light
Ziaedin Shafiei 05 Dec 2015
Contents 1. The Speed of Light in Vacuum is Constant 2. Vector Presentation 3. Direction of Light is Affected by the Speed of its Source 4. The Reason for the Directional Effect 5. Mechanism of the Directional Effect 6. A Possible Alternative 7. Summary and Comments
05/12/2015
Inquiry Into the Speed of Light
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The Speed of Light in Vacuum is Constant π£ = Speed of IRF
π
π£
π¦ π 3 π 2
π π 1
π π₯ Figure 1
05/12/2015
Suppose a laser torch, such as ππ , ππ or ππ in an inertial reference frame (IRF), emits visible light in any direction. Based on Maxwell equations and the special theory of relativity 1. The speed of light, π, in any direction is the same for an observer within the frame 2. The speed of the IRF, π£, also does not affect the speed of light measurement by any observer outside the frame 3. That is any non-accelerating movement of the frame or torch has no effect on the measurement of π by any observer inside or outside of an IRF The speed of light is a universal physical constant Inquiry Into the Speed of Light
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Vector Presentation It is generally accepted in modern physics that: β’ Any movement of the source of light does not affect the magnitude of the speed of light measurement β’ Vector operation does not apply for light, as depicted for two parallel movement cases below. Quantity and direction of the speed of the source has no effect on c
1
Figure 2 π£
π + π£ π
π π£
π£
π
2
π β π£ π
π light and torch speed 05/12/2015
π£
Incorrect vector calculation Inquiry Into the Speed of Light
π
Measured speed 4
Direction of Light is Affected by the Speed of its Source β’ But what about the effect of the source movement on the direction of light for non parallel cases? β’ Mathematically it also should have no effect β’ However, based on SR, for an outside observer the direction of light is affected by the speed of the source π£2 π 1+ 2 π
π£ π
1/2
π£
π Incorrect speed of light
Light and torch speed
π
Accepted speed of light
π Inferred speed of light
Figure 3 05/12/2015
Inquiry Into the Speed of Light
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The Reason for the Directional Effect β’ One major reason and at the same time application for this effect is Einsteinβs light clock which is a theoretical instrument β’ Assumed travel path of light for stationary and moving clocks are depicted in Figure 4 β’ Key conclusions of SR are based on the analysis of the working assumption of the clock in various thought experiments Figure 4 Top mirror
Light pulse
πΏ
π£
Direction of light according to SR
Bottom mirror
Moving clock
Stationary clock 05/12/2015
Inquiry Into the Speed of Light
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Mechanism of the Directional Effect β’ If the direction of light beam can be changed by a moving mirror then the light direction in a moving clock should not be a uniform zigzag β’ The angle of the light beam should get smaller with each bounce as shown in Figure 5 Moving clock
π£
π2
π1
π3
β¦ < π3 < π2 < π1 < 90π¨
Figure 5 05/12/2015
Inquiry Into the Speed of Light
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A Possible Alternative β’ The working of the clock is not experimentally verified thus the accepted light behaviour may not fit the reality β’ One possibility is that light carries on its vertical direction after a bounce from the moving light clock as shown in Figure 6 β’ Only the result of an experiment can provide an affirmative answer β’ The implication of this possible alternative is beyond this inquiry π£
Top mirror
πΏ
Bottom mirror
Stationary clock 05/12/2015
Figure 6
Moving clock
Inquiry Into the Speed of Light
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Summary and Comments β’ According to SR the quantity of the speed of light is not affected by the speed of its source but its direction is β’ This is not mathematically and rationally consistent β’ The light clock is a thought equipment with no verification of its real operation β’ It is possible that the speed of the source of light has no physical effect on light, neither its quantity nor its direction β’ In that case, one can also verify the absolute speed of any IRF or any source of light perpendicular to the direction of light β’ An experiment is needed to be designed, the result of which is the scientific arbiter 05/12/2015
