According to new observations from the James Webb Space Telescope, our universe is expanding about eight percent faster than previously thought.

There is a long-standing discrepancy between the observed rate of expansion of the universe and the rate we thought possible based on our knowledge of the universe, known as the Hubble tension.

Now, according to a new paper in The Astrophysical JournalNew measurements from Webb confirmed that the Hubble voltage is not caused by some error in our observations, but potentially by the influence of dark matter and dark energy.

“The discrepancy between the observed rate of expansion of the universe and the predictions of the Standard Model suggests that our understanding of the universe may be incomplete,” study co-author Adam Riess, a Nobel laureate and professor of physics and astronomy at Johns Hopkins University. , he said in a statement.

“With NASA’s two flagship telescopes now confirming each other’s findings, we have to accept that [Hubble tension] a very serious problem – it’s a challenge, but also an incredible opportunity to learn more about our universe.”

In the paper, the researchers describe how they analyzed data from JWST’s first two years in space to calculate the rate at which the galaxies were moving away from each other.

This new data confirms findings from the Hubble Space Telescope that the universe is expanding faster today than it did during its first few billion years.

The rate at which the universe is expanding is a figure known today as the Hubble constant, which is usually measured in units of kilometers per second per megaparsec (km/s/Mpc), where a megaparsec (Mpc) is about 3.26 million light years. .

Based on our knowledge of the universe, the Hubble constant should be lower than the value observed by the Hubble Space Telescope by about 5–6 km/s/Mpc. This difference, which cannot easily be explained by random errors or uncertainties, is the Hubble voltage.

The JWST measurements were found to be in close agreement with the Hubble measurements, meaning that the strain was not caused by an error in the Hubble instrument.

“The Webb data is the first high-resolution look at the universe and really improves the signal-to-noise ratio of the measurements,” co-author Siyang Li, a graduate student at Johns Hopkins University, said in a statement.

The Hubble stress must therefore be due to unknown gaps in our knowledge of the physics of the universe.

When was the James Webb Telescope launched?

The James Webb Space Telescope was launched on December 25, 2021 aboard an Ariane 5 rocket from the Guyana Space Center in French Guiana.

As part of a collaborative project between NASA, ESA (European Space Agency) and CSA (Canadian Space Agency), JWST was sent to its operational location at the second Lagrange point (L2), approximately 1 million miles from Earth, and became fully operational for scientific observations in July 2022.

Observations in the late 1990s revealed that the rate of expansion of the universe has been accelerating since the big bang about 13.8 billion years ago due to the influence of dark energy.

Dark energy is a mysterious and poorly understood form of energy that makes up approximately 68 percent of the total energy density of the universe. It appears to have a repulsive gravitational effect, counteracting the attractive force of gravity, resulting in the acceleration of the universe’s expansion.

“One possible explanation for the Hubble tension would be if there was something missing in our understanding of the early universe, such as a new component of matter—early dark energy—that gave the universe an unexpected kick after the Big Bang,” Marc Kamionkowski, a Johns Hopkins cosmologist involved in the calculation of the Hubble constant, who was not involved in this new study, said in a statement.

“And there are other ideas like the funny properties of dark matter, exotic particles, the changing mass of electrons or primordial magnetic fields that can help. Theorists are allowed to be pretty creative.”

Reference

Riess, AG, Scolnic, D., Anand, GS, Breuval, L., Casertano, S., Macri, LM, Li, S., Yuan, W., Huang, CD, Jha, S., Murakami, YS, Beaton, R., Brout, D., Wu, T., Addison, GE, Bennett, C., Anderson, RI, Filippenko, AV, & Carr, A. (2024). JWST validates HST distance measurements: Supernova subsampling explains differences in JWST local H0 estimates. The Astrophysical Journal, 977(1), 120. https://doi.org/10.3847/1538-4357/ad8c21