One of the biggest mysteries in physics, dubbed the Hubble tension, might finally get solved by a lost type of dark matter. The Hubble tension refers to an extended contradiction in physics: The Universe is developing, but some measurements offer different results for exactly how fast is happening.
Physicists detail the expansion rate with a number, dubbed the Hubble constant (H0). H0 describes an engine of sorts that’s tearing things apart over extended lengths across the Universe. According to Hubble’s Law, the farther away an item is from us, the faster is traveling.
And there are two types of calculations for H0. You can examine the galaxies and stars, or measure directly how quickly they’re moving. Or you can explore the cosmic microwave background and afterglow of the Big Bang that covers the whole Universe, and other essential data about its development. Recently, however, a team of physicists succeeded in shedding light on the long mystery of Hubble tension.
The Lost Type of Dark Matter and the Hubble Tension
A team of physicists is now claiming that the Universe might have evolved a lot between the period after the Big Bang and today. If an early type of dark matter destroyed the existence, that loss would have turned the mass of the Universe, and with less weight, there would result in a less gravity keeping the Universe together. It would have also influenced the velocity at which the Universe evolves. Then, it would lead to the contradiction between the CMB and the direct calculations of the Universe’s development rate.
A lost dark matter’s volume would have represented an essential part of the entire mass of the Universe when it existed. It would also lead to a different development range when the CMB evolved right after the Big Bang.
Nowadays, after billions of years, it wouldn’t exist. And all the galaxies and stars we can examine would be moving away from us at a velocity determined by the Universe’s actual mass. Most attempts to solve the Hubble tension include tweaking Lambda-CDM (Cold Dark Matter) in a way. Some scientists suggested there may be issues with the actual measurements of the local Universe.
The recent study doesn’t indicate what particles the lost dark matter might contain. Still, it strongly proposes that warm dark matter might have been made of sterile neutrinos – some particles that other scientists also think are likely out there. Whatever it is, it could have changed into something more feebly and different interacting when it collapsed. If that something else was divided differently in the Universe or interacted strangely with other particles in the Universe. And then it would modify how the Universe evolved.