The charge per unit at which the universe expands has been changing since the Big Bang , but this is not expected in the presently accepted simulation of cosmogony . Still , it seemsthis discrepancydefinitely be and new Hubble reflection support that the mismatch between the model and observations is very much existent .
The team performed elaborate observation of Cepheid varying ace , a special form of stars that have been used to estimate intergalactic distances . The team ’s work has strengthened those length appraisal and improved the value of the Hubble constant , the measurement of the expansion rate of the population . The study has been accepted for publishing inThe Astrophysical Journaland is currently usable onarXiv .
The value remains 9 percent high than what ’s expected using data from the cosmic microwave scope , radiation pass off 380,000 years after the Big Bang . The new measurement also render that the likelihood that the variance is just an error is now one in 100,000 , a pregnant betterment on the one in 3,000 suggested by previous measurement .
“ This mismatch has been growing and has now achieve a decimal point that is really insufferable to disregard as a good fortune . This is not what we expected , ” labor drawing card Adam Riess , Nobel Laureate and Professor of Physics and Astronomy at Johns Hopkins University , said in astatement .
“ This is not just two experiments dissent , ” he explained . “ We are measuring something fundamentally different . One is a measurement of how fast the universe is boom today , as we see it . The other is a prediction establish on the physics of the other creation and on measurements of how fast it ought to be expanding . If these values do n’t accord , there becomes a very unattackable likeliness that we ’re missing something in the cosmologic fashion model that relate the two eras . ”
The exact mechanics that is making this find is presently undecipherable . It might take some new purgative . investigator are concerned in reducing the uncertainty surrounding the Hubble constant . This was 10 percent in 2001 , 5 percent in 2009 , and is 1.9 percent in the current work . Their end is to land this uncertainty down to 1 percent .
Cepheid variable are star that throb with a well - defined stable period , which is linked to the star ’s true luminosity . This relationship was discovered by American astronomer Henrietta Swan Leavitt . With that value , it is potential to estimate the distance of these objects , and they have help as utilitarian calibration tools for further distances hold with supernova . By expanding our understanding of Cepheid variable , we can meliorate all the distance estimate calibrated using these stars .
