<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Meta</i>
<br />With erroneous assumptions such as "Gravity bends light near mass"<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Who has made such an assumption? Certainly not science, which has repeatedly <i>measured</i> light-bending by the Sun.
The earliest measures were of questionable accuracy: optical measurements of stars during eclipses of the Sun by Eddington in 1918). But this experiment has been repeated many times since (so often that it is no longer publishable) with better weather, controls, instruments, filters, and measuring apparatus. The end result is no longer in doubt, and is now sometimes used as a lab project for training graduate students.
But modern observations have rendered the optical measurements of historical interest only. This began with Phys.Rev.Lett. 24, 1373-1376 (1970): "Measurement of the of 9.602-GHz radiation from 3C279 in the solar gravitational field", G.A. Seielstad, R.A. Sramek & K.W. Weiler. The position of radio source [quasar] 3C279 was interferometrically monitored during its annual occultation by the Sun in October 1969 to determine the deviation of its 9.602-GHz radiation in the solar gravitational field. Repeated instrumental calibration and negligible coronal refraction enabled the measurement of the general relativity “light bending" deflection. The result was 1.77” +/- 0.20” at the limb of the Sun, as compared with the predicted value of 1.75”.
More recently, we have D.S. Robertson et al., Nature 349 (1991) 768: 74 radio sources, over 300,000 VLBI observations; fitting not just deflection at the limb of the Sun, but the amount and functional form of deflection as a function of distance from the limb. The result at all angular distances agrees with relativity, whose prediction is verified to within a standard error of 0.2%.
Or D.E. Lebach et al., Phys. Rev. Lett. 75 (1995) 1439: VLBI measurements of two extragalactic radio sources at three frequencies; a total of over 20,000 measurements; standard error of less than 0.2%.
Finally, we have the coup de grace of experimental measurements of light-bending by mass: See
physicsweb.org/article/news/7/9/14
or Nature 425, ix & 374-376 (2003). Using signals from Earth to the Cassini spacecraft, the magnitude of the predicted light-bending effect produced by the Sun was shown to agree with GR predictions to within 23 parts per million.
Calling a solidly established experimental result an "assumption" sounds like someone with a falsified theory or idea clinging to hope and ignoring all counter-evidence. But the key to making intellectual progress is to let pet theories go when the first solid evidence goes against them. The opposite is just another form of bias, such as mainstream science is riddled with. -|Tom|-
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