In science fiction, the concept of a mirror universe is a prevalent one. In an universe comparable to ours, we may encounter our evil twin or a version of ourselves who really asked out our high school crush.

However, the notion of a mirror universe has been examined extensively in theoretical cosmology, and as a new study indicates, it may be useful in resolving cosmological constant concerns.

The Hubble constant, often known as the Hubble parameter, is a measure of how fast our Universe is expanding. Edwin Hubble was the first to establish this expansion, utilizing data from Henrietta Leavitt, Vesto Slipher, and others.

Measurements of this expansion over the next several decades decided on a pace of roughly 70 (km/sec)/Mpc. Give or take a few points. Astronomers expected the various approaches to agree on a single number as our observations got more accurate, but this did not happen.

In fact, during the last several years, measurements have gotten so exact that they are now incompatible. This is commonly referred to as the "cosmic tension" issue.

At this moment, the observed Hubble constant values are divided into two groups.Observations of objects such as distant supernovae offer a higher estimate, about 73 (km/sec)/Mpc, based on measurements of variations in the cosmic microwave background. Theoretical physicists are attempting to figure out why something doesn't seem to add up. This is where the mirror universe might play a role.

Theoretical physics is a place where strange ideas come and go. No exception applies to the concept of a mirror universe.

In the 1990s, it was extensively researched as a solution to the matter-antimatter symmetry problem. In the lab, we can make matter particles, but we can make antimatter. They are always sold in a set of two. Where did all the antimatter siblings go when particles first created in the early Universe?

One theory suggested that the Universe was created in pairs. Our universe is made up of matter, and there is a parallel universe made up of antimatter. The problem has been resolved. For a variety of reasons, the concept has fallen out of favor, but a new research examines how it may be used to address the Hubble dilemma.

The researchers uncovered an invariance in so-called unitless parameters. The fine structure constant, with a value of roughly 1/137, is the most well-known of them.

In essence, you may combine measurable parameters in such a manner that all of the units cancel out, giving you the same number regardless of the units you pick, which is useful for theoreticians.

The researchers discovered that when cosmological models are tweaked to fit actual expansion rates, certain unitless constants remain the same, implying an underlying cosmic symmetry. If you apply this symmetry more generally, you may regulate the rate of gravitational free-fall and the rate of photon-electron scattering to make the various Hubble measurement methods more consistent. And if this invariance is true, it means that a mirror universe exists. One that would have a little gravitational influence on our cosmos.

It should be noted that this research is primarily a proof of concept. It explains how cosmic invariance may solve the Hubble constant problem, but it doesn't prove it.

That will necessitate a more comprehensive model. However, it's a fascinating concept. And it's comforting to know that if your bad doppelganger exists, they can only have a gravitational effect on your life...