Researchers from the Max Planck Institute for Gravitational Physics (Albert Einstein Institute; AEI) in Hannover together with international colleagues have published their second Open Gravitational-wave Catalog (2-OGC). They used improved search methods to dig deeper into publicly available data from LIGO’s and Virgo’s first and second observation runs. Apart from confirming the ten known binary black hole mergers and one binary neutron star merger, they also identify four promising black hole merger candidates, which were missed by initial LIGO/Virgo analyses. These results demonstrate the value of searches in public LIGO/Virgo data by research groups independent of the LIGO/Virgo collaborations. The research team also makes available its complete catalogue in addition to detailed analysis of more than a dozen possible binary black hole mergers.

“We incorporate cutting edge methods,” says Alexander Nitz, a staff scientist at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) in Hannover, who led the international research team. “Our improvements enable discovering fainter binary black hole mergers: the four additional signals show that this works!”

The results were published in The Astrophysical Journal today.

The Earth, solar system, the entire Milky Way and the few thousand galaxies closest to us move in a vast “bubble” that is 250 million light years in diameter, where the average density of matter is half as high as for the rest of the universe. This is the hypothesis advanced by a theoretical physicist from the University of Geneva (UNIGE) to solve a conundrum that has been splitting the scientific community for a decade: At what speed is the universe expanding? Until now, at least two independent calculation methods have arrived at two values that are different by about 10% with a deviation that is statistically irreconcilable. This new approach, which is set out in the journal Physics Letters B, erases this divergence without making use of any “new physics.”

The universe has been expanding since the Big Bang occurred 13.8 billion years ago—a proposition first made by the Belgian canon and physicist Georges Lemaître (1894−1966), and first demonstrated by Edwin Hubble (1889−1953). The American astronomer discovered in 1929 that every galaxy is pulling away from us, and that the most distant galaxies are moving the most quickly. This suggests that there was a time in the past when all the galaxies were located at the same spot, a time that can only correspond to the Big Bang. This research gave rise to the Hubble-Lemaître law, including the Hubble constant (H0), which denotes the universe’s rate of expansion. The best H0 estimates currently lie around 70 (km/s)/Mpc (meaning that the universe is expanding 70 kilometers a second more quickly every 3.26 million light years). The problem is that there are two conflicting methods of calculation.

Physicists are using analog black holes to better understand gravity.

Hmmm dark matter perhaps or a still unknown type of exterrestial physics. Much like bootes which in my expert opinion is an alien dimension maybe there are still Easter eggs hidden in the fabric of our universe that can take several lifetimes to understand even with advanced technology understanding may still be like scratching at the ceiling of infinity of understanding but may not be as difficult.

It’s a mystery that’s been puzzling astronomers for years.