In 2023, Chae's initial study of wide binaries - pairs of stars gravitationally bound but separated by vast distances - revealed unexpected orbital accelerations. These findings indicated that, at accelerations below approximately 1 nanometer per second squared, the orbital motions of these binaries were greater than what Newtonian physics would predict. This deviation became more pronounced, reaching a boost factor of around 1.4, at accelerations below 0.1 nanometer per second squared. Such anomalies in acceleration could not be accounted for by dark matter, given the constraints posed by galactic dynamics and cosmological observations.

Remarkably, these observations align closely with predictions from modified Newtonian dynamics (MOND) theories like AQUAL, proposed over 40 years ago by physicist Mordehai Milgrom and the late Jacob Bekenstein. These theories suggest alterations to Newtonian physics under specific conditions, such as the low accelerations observed in wide binaries.

Chae's recent independent investigation focused on a meticulously chosen sample of 'pure' wide binaries. By excluding systems potentially containing unobserved stars, Chae aimed to eliminate the need for calculating hidden gravitational effects, thereby enhancing the accuracy of the results. Out of a conservative selection of 2,463 pure binaries - less than 10% of the earlier study's sample - Chae's approach was stringent, given that at least half of all binary systems are expected to be pure.

Employing two distinct algorithms to test gravitational theories, Chae's study reaffirmed the 2023 findings. Both algorithms showed consistent results, with a clear deviation from Newtonian predictions starting at separations of about 2,000 AU and accelerations around 1 nanometer per second squared. This deviation intensified at greater separations or lower accelerations, with a nearly constant acceleration boost of 40 to 50 percent, up to the observed limit of about 20,000 AU or 0.01 nanometer per second squared.

The significance of these findings is underscored by their agreement with independent results from Xavier Hernandez's group, who employed a completely different sample and algorithm. This convergence of evidence from independent studies adds considerable weight to the observed gravitational anomalies.

Chae commented on the importance of these findings, expressing a sense of awe at the direct evidence for the low-acceleration gravitational anomaly and the emerging mysterious reality of gravity. He also addressed the quality of the new sample, emphasizing its freedom from data quality concerns raised in previous literature.

Chae's response to recent contradicting claims by Indranil Banik and coauthors highlights issues with their methodology, particularly the exclusion of crucial Newtonian-regime binaries and the neglect of velocity errors in their statistical modeling. He asserts that these factors invalidate their conclusions.

The observed gravitational anomalies, consistent with MOND-type gravity phenomenology, open exciting possibilities for theoretical physics and mathematics. Echoing the historical significance of Mercury's perihelion precession, which led to Einstein's relativistic gravity theory, Chae suggests that these wide binary anomalies could herald a similar paradigm shift in our understanding of gravity.

Research Report:Robust Evidence for the Breakdown of Standard Gravity at Low Acceleration from Statistically Pure Binaries Free of Hidden Companions

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