قالب وردپرس درنا توس
Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ The gravitational waves will settle the cosmic conundrum

The gravitational waves will settle the cosmic conundrum



3.8 billion years. Its current rate of expansion, known as the "Hubble Constant", gives the time that has elapsed since the Big Bang.

However, the two best methods used to measure the Hubble constant have contradictory results, suggesting that our understanding of the structure and history of the universe – the "standard cosmological model" – may be incorrect. The study published today in Physical Review Letters shows how new independent data from gravitational waves emanating from binary neutron stars is called "standard sirens" will interrupt the deadlock between contradictory measurements once and for all.

"We calculated that, by observing 50 binary neutron stars over the next decade, we will have enough data on gravitational waves to determine independently the best measurement of the Hubble Constant Constants," said lead author Dr. Steven Feeney of the Center for computational astrophysics at the Flatiron Institute in New York. "We must be able to find enough mergers to answer this question within five to ten years."

The Hubble Constant, product of the work of Edwin Hubble and Georges Lematter in the 1920s is one of the most important numbers in cosmology, Constant is essential to assess the distortion of space and the age of the universe as well as the study of its destiny, "said co-author of the UCL study, Professor of Physics and Astronomy Hiranya Peiris

. using two methods – one observation of Cepheid stars and supernovae in the local universe, and second use of measurements of cosmic background radiation from the early universe – but these methods do not give the same values, which means our standard hair a model may be defective

Feeney, Peiris and colleagues have developed a universally applicable technique that calculates how gravitational wave data will solve the problem.

Gravitational waves emit when binary neutron stars stop at each other before they collide in bright light can be detected by telescopes. UCL researchers were included in the opening of the first light of a gravitational wave event in August 2017.

Events of binary neutron stars are rare, but they are invaluable in providing another way to track the expansion of the universe. The gravitational waves they emit cause space-time waves that can be detected by LIGO gravity wave observatories and Virgo experiments that accurately measure the distance of the system from the Earth.

By further detecting the light from the accompanying explosion, astronomers can determine system speed and therefore calculate the Hubble constant value using Hubble's law.

For this study, the researchers modeled how many such observations would be needed to solve the exact matter of constant Hubble measurement. "This, in turn, will lead to the most accurate picture of how the universe is expanding and helping us to improve the standard cosmological model," concluded Professor Peiris.


See also:
Can gravitational waves reveal how fast our universe expands?

More Information:
Stephen M. Feeney, Hiranya V. Peiris, Andrew R. Williamson, Samaya M. Nissanke, Daniel J. Mortlock, Justin Alsing and Dan Scolnic, "Perspectives to Resolve Standard Harsh Pressures on Hubble" will be published in Physical Review Letters on Thursday, February 14, 2019.

Journal Title:
Physical letters for review

Submitted by:
Simons Foundation


Source link