Hyperphysics: Hafel-Keating experiment

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http://hyperphysics.phy-astr.gsu.edu/HBASE/relativ/airtim.html#c5

I don't understand the approximation T0 = -TS that they make in the final step of the section "Kinematic Time Shift Calculation". From this, and the other equations in this section, I get

[tex]-T_0=T_0\left ( 1+\frac{R^2\omega^2}{2c^2} \right )[/tex]

[tex]-1=1+\frac{R^2\omega^2}{2c^2}[/tex]

[tex]c^2=\frac{R^2\omega^2}{-4}[/tex]

[tex]c=\pm \frac{R\omega}{2i}[/tex]

but how can this be when c is a constant positive real number, not dependent on the product of the rotation of the Earth with its radius? And

[tex]T_A=T_S-T_S\left ( \frac{2R\omega v+v^2}{2c^2} \right )[/tex]

[tex]T_0\left ( 1+\frac{R^2\omega^2}{2c^2} \right )=-T_S\left ( -1+ \frac{2R\omega v+v^2}{2c^2} \right )[/tex]

[tex]T_0\left ( 1+\frac{R^2\omega^2}{2c^2} \right )=T_0\left ( -1+ \frac{2R\omega v+v^2}{2c^2} \right )[/tex]

[tex]4c^2= 2R\omega v+v^2 - R^2\omega^2[/tex]

[tex]c=\frac{\sqrt{(R\omega+v)^2-2R^2\omega}}{2}[/tex]

which can't be right, since c doesn't depend on these arbitrary variables: radius of the earth, etc.
 
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Rasalhague said:
http://hyperphysics.phy-astr.gsu.edu/HBASE/relativ/airtim.html#c5

I don't understand the approximation T0 = -TS that they make in the final step of the section "Kinematic Time Shift Calculation". From this, and the other equations in this section, I get

[tex]-T_0=T_0\left ( 1+\frac{R^2\omega^2}{2c^2} \right )[/tex]

[tex]-1=1+\frac{R^2\omega^2}{2c^2}[/tex]

[tex]c^2=\frac{R^2\omega^2}{-4}[/tex]

[tex]c=\pm \frac{R\omega}{2i}[/tex]

but how can this be when c is a constant positive real number, not dependent on the product of the rotation of the Earth with its radius? And

[tex]T_A=T_S-T_S\left ( \frac{2R\omega v+v^2}{2c^2} \right )[/tex]

[tex]T_0\left ( 1+\frac{R^2\omega^2}{2c^2} \right )=-T_S\left ( -1+ \frac{2R\omega v+v^2}{2c^2} \right )[/tex]

[tex]T_0\left ( 1+\frac{R^2\omega^2}{2c^2} \right )=T_0\left ( -1+ \frac{2R\omega v+v^2}{2c^2} \right )[/tex]

[tex]4c^2= 2R\omega v+v^2 - R^2\omega^2[/tex]

[tex]c=\frac{\sqrt{(R\omega+v)^2-2R^2\omega}}{2}[/tex]

which can't be right, since c doesn't depend on these arbitrary variables: radius of the earth, etc.

HK is poorly explained using SR, a correct explanation requires GR. I am quite sure that I gave a GR-based explanation for HK somewhere in this forum. It is simply calculating the proper time [tex]\tau[/tex] by integrating the expression in coordinate time t. The expression can be derived straight from the general Schwarzschild metric setting:

[tex]dr=d\theta=0[/tex],
[tex]\frac{d\phi}{dt}=\omega +\frac{v_1}{R}[/tex]
[tex]\frac{d\phi}{dt}=\omega -\frac{v_2}{R}[/tex]

depending on the direction of plane motion
 
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