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pawprint
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I'm learning about gravitational waves and associated matters (detectors etc.). I don't do much maths, but physics is in my bones. Totally at home with classical physics and SR; as for GR- well, I'm O.K. as long as you stay on the 'friendly' side of event horizons...
I'm comfortable with the Wikipedia article 'Gravitational waves' until halfway down the page (just below this image...)
(Wikipedia commons)
...where it states without qualification that "gravitational waves can pass through any intervening matter without being scattered significantly." I seek clarification of the term 'scattered significantly'.
The above image probably reflects a neutron star binary system with an orbital period of about 4 seconds, resulting in a wavelength around 2 light seconds and frequency of 0.5 Hertz.
Let me place the Earth in that image near the plane of greatest gravitational wave distortion. Also allow that the binary system is 40 times more rapid than shown above: It's now inspiralling significantly and has a wavelength close to one Earth diameter and a frequency around 20 Hertz.
The Earth itself is being distorted by the wave. It is immersed within and conforming to 4 dimensional spacetime, as it must. In our (The Earth's) frame of reference our clocks and rulers are being distorted but so are we as observers; we see nothing of this directly.
If the radiated spacetime wave is of sufficient magnitude an observer whose frame of reference is distant from the orbital plane of the radiating system should be able to measure these distortions. The observer might, for example, observe Doppler shifts in Earthly EM transmissions. Our Sun would show slightly broadened emission and absorbtion lines.
Since I'm stepping into a new arena I have probably not expressed myself well. I welcome suggestions and corrections.
My questions-
1) Does the above require clarification? Is anything about it inherently impossible or wrong?
2) If not does the Earth's interaction with the spacetime wave 'significantly scatter' the wave?
3) The base question- Does the gravitational interaction increase entropy?
I'm comfortable with the Wikipedia article 'Gravitational waves' until halfway down the page (just below this image...)
(Wikipedia commons)
...where it states without qualification that "gravitational waves can pass through any intervening matter without being scattered significantly." I seek clarification of the term 'scattered significantly'.
The above image probably reflects a neutron star binary system with an orbital period of about 4 seconds, resulting in a wavelength around 2 light seconds and frequency of 0.5 Hertz.
Let me place the Earth in that image near the plane of greatest gravitational wave distortion. Also allow that the binary system is 40 times more rapid than shown above: It's now inspiralling significantly and has a wavelength close to one Earth diameter and a frequency around 20 Hertz.
The Earth itself is being distorted by the wave. It is immersed within and conforming to 4 dimensional spacetime, as it must. In our (The Earth's) frame of reference our clocks and rulers are being distorted but so are we as observers; we see nothing of this directly.
If the radiated spacetime wave is of sufficient magnitude an observer whose frame of reference is distant from the orbital plane of the radiating system should be able to measure these distortions. The observer might, for example, observe Doppler shifts in Earthly EM transmissions. Our Sun would show slightly broadened emission and absorbtion lines.
Since I'm stepping into a new arena I have probably not expressed myself well. I welcome suggestions and corrections.
My questions-
1) Does the above require clarification? Is anything about it inherently impossible or wrong?
2) If not does the Earth's interaction with the spacetime wave 'significantly scatter' the wave?
3) The base question- Does the gravitational interaction increase entropy?
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