There is an odd streak in the universe – and we still don’t know why

An anomaly in the temperature of the universe has long perplexed physicists, and a new analysis of the data of several radio-tescopes only alled the mystery of what causes it.

This strange sequence is seen in the remanence of the Big Bang – the radiation which has been heading towards us since the start of time, called Cosmic microwave (CMB). Physicists agree that our point of view of the universe, or the position inside, should in no case be exceptional, so they expect the CMB to be almost the same in all directions. But the measures show the opposite: there is an axis along which the CMB goes from colder to warmer. This is called a dipole, and Lukas Böhme at Bielefeld University in Germany and its collaborators have now shown how deeply it is by turning to the data of RadioTelescopes.

Böhme says that the existence of a dipole in the CMB is not surprising in itself, but its size does not correspond to our strongest cosmology models. The radiation emitted from a source in motion or measured by someone who moves – and the earth, our solar system and all our galaxy move – will move to be warmer or colder depending on this movement, due to the Doppler effect and other relative movement effects which arise from the theory of special relativity. But the dipole that researchers have observed for decades corresponds to a movement approximately ten times faster than expected.

To have a better vision of this divergence, Böhme and his colleagues analyzed the data of six telescopes which collect radio waves. After a meticulous analysis, they reduced the data to the three they found the most precise and analyzed them according to a new model where the radio waves come from in the sky. Böhme says that their approach was similar to the division of the sky into pixels and carefully determine how many sources of radiation are contained in each. However, even with this meticulous adjustment, the dipolar mystery has persisted.

Dragan Huterer of the University of Michigan says that the new observation is interesting exactly due to the prudence of the analysis of the team. This is a fairly important step towards creating the dipole as an undeniable fact on the CMB, which would be a big problem, he said. Indeed, this would imply that we do not understand something about the structure of our neighborhood in the cosmos, or the whole universe is not like even if our most successful theories suggest. However, Huterer says that the measures of radio-astronomy are notoriously difficult to make precise so that there can still be systematic errors in the data.

Part of the challenge comes from the fact that all radio signals collect telescopes are low, explains Böhme. “It’s a really small thing we want to measure. It is really difficult to calibrate your [radio] The investigation is so precise, ”he says. But this is not the only proof of the dipole that we have. The infrared radiation from Quasars seems to strengthen the measures of the radio waves, but it will really be up to the future telescopes to add more precision.

Reference: Physical examination lettersforthcoming