A Bizarre New Form of Dark Matter Could Uncover the Mysteries of Gravity—And Our Universe
A new study proposes self-interacting dark matter as a potential solution to long-standing cosmic mysteries, including the 'scar' on the GD-1 stellar stream. Researchers at UC Riverside argue this form of dark matter could explain observable structures and gravitational effects, unlike traditional collisionless models.
Scientists may have uncovered a new clue to observing dark matter, a mysterious substance believed to make up 85 percent of the universe’s matter. A recent study published in *Physical Review Letters* suggests dark matter could be 'self-interacting,' meaning its particles collide with each other instead of passing through one another undetected. This theory, led by physicist Hai-Bo Yu from the University of California, Riverside, proposes that such interactions could create dense cores and explain cosmic structures visible through telescopes. The idea challenges the long-held assumption that dark matter is 'cold' and collisionless. Yu’s research indicates self-interacting dark matter could resemble a crowd of people bumping into each other, producing energy dense enough to leave observable marks in space. However, current supercolliders lack the power to detect these particles, leaving direct proof elusive. One key piece of evidence supporting this theory is the 'scar' on GD-1, a stellar stream 25 light-years away. Yu and his team previously suggested in *Astrophysical Journal Letters* that the scar’s size and density could only result from a collision with a self-interacting dark matter object. Traditional cold dark matter models fail to explain this phenomenon. Yonatan Khan, a physicist at the University of Toronto, notes that while self-interacting dark matter isn’t new, detecting it remains difficult due to observational limitations. The challenge lies in identifying the right astrophysical signatures that distinguish this form of dark matter from others. If confirmed, the discovery could solve puzzles about gravity and the universe’s structure, offering a breakthrough in cosmology.
This content was automatically generated and/or translated by AI. It may contain inaccuracies. Please refer to the original sources for verification.