researcher have measure the gravitational red shift of the Sun with the highest precision yet , confirming a theoretical prevision made by Einstein in 1920 .
photon are particle of visible radiation that are affected by gravitative force field . The path of photons can be bent by obtuse bodies and their wavelength can stretch as they climb out of a gravitational potentiality well . This wavelength of luminance escaping a gravitative well is shifted slightly towards the redness and is referred to as a gravitational redshift . As reported inAstronomy & Astrophysics , the force is small-scale but measurable even for the Sun .
Einstein compose a hundred ago : " For the Sun , the theoretical redshift predicted is approximately two - millionth of the wavelength . Whether this effect really exists is an undetermined question , and astronomers are presently go firmly to resolve it . For the Sun , its macrocosm is difficult to judge because the effect is so small . "
The measure of the solar gravitational redshift required an ingenious approach . The first footmark was to depend at the spectrum of the Sun . In unproblematic terms , this is like using a prism and unveil all the colors that make up the light of the Sun . In the spectrum , there are dark short letter created by elements in the Sun .
The gravitational redshift move these furrow to longer wavelength than they would appear in the lab . The team focused on some of the iron contrast and used the light rebound off the Moon to make the measurement . The instrument they used was the High Accuracy Radial - velocity Planet Searcher ( HARPS ) , calibrate with a state - of - the - art laser absolute frequency comb , permit it to make extremely exact measurements .
The measurements are very much consistent with theoretical prevision of the solar gravitational redshift .
" meld the preciseness of the HARPS instrument with the optical maser frequency comb , we have been able-bodied to evaluate with high accuracy the position of the iron lines in the solar spectrum , " leave author Dr Jonay González Hernández , from the Instituto de Astrofísica de Canarias , said in astatement . " This has enabled us to verify one of the predictions of Einstein ’s Theory of General Relativity , the gravitational red shift , to a precision of just a few meters per secondly . "
The gravitational redshift phenomenonhas also been confirmedfor the stars that orbit the supermassive smutty hole at the heart and soul of the Milky Way , which was part of the work of the2020 Nobel Prize winnersReinhard Genzel and Andrea Ghez .
