Gravitational waves

[lcwelch]

Since gravity in GR is a result of the distortion of the space-time fabric of the universe and any experimental equipment is embedded in that same fabric why is is it not recognized that gravitational waves may distort the experimental equipment such that detection is impossible? As an analogy, I think of taking a piece of rubber sheet (a "pseudo-2-D universe") and making two marks "exactly" one meter apart. If one stretches the rubber the marks, which define a meter, move apart. Only a meter stick OUTSIDE of that pseudo-universe could detect the stretching.

[Q-reeus]

Quite a while back I made the same argument. There is a standard counterargument e.g.: https://www.aapt.org/doorway/tgrutalks/ ... 0waves.pdf
[following link now seems dead: http://gw.aei.mpg.de/images/Saulson_199 ... 65_501.pdf]
Along the lines that while space stretches and squeezes (rigid ruler frame), the temporal component is unaffected. Which leads to light but not rigid matter stretching and squeezing.
More technical articles:
http://arxiv.org/abs/0910.4372v1
http://arxiv.org/abs/1103.4783
but note the many following 'Searching for' articles that author made or contributed to: http://arxiv.org/find/gr-qc/1/au:+Corni ... /0/all/0/1
The notion of a GW distorting space but not time is imo badly mistaken. Sorry but won't go into details. Meanwhile, the long wait for detection gets ever longer.

[lcwelch]

Certainly gravity affects time. Perhaps the argument boils down to that a gravitational wave will equally retard and advance time so that the net effect is zero?

[Q-reeus]

Certainly gravity affects time. Perhaps the argument boils down to that a gravitational wave will equally retard and advance time so that the net effect is zero?

Huh? So if 1 + -1 = 0, why not just say 0 in the first place? The standard quadrupole GW formula explicitly has only the spatial components effected (time appears only as wave propagation parameter). And, to square with the rigid ruler outlook, the only way to interpret them is as tidal accelerations - 'g' forces. Which in my book is far different than transversely uniform fluctuations in the spatial metric giving the + or × mode 'shear' distortions shown in many illustrations. Things don't really add up and the logical answer imo is there is no such thing as quadrupole mode GW's.