Young galaxies have surprisingly strong magnetic fields

The origin of magnetic fields in galaxies remains a mystery to astronomers. The usual hypotheses for reinforcing magnetic fields continuously for billions of years. However, the latest results from Simon Lilly's group contradict the above assumption and reveal that young galaxies also have very strong magnetic fields.

Simon Lilly, professor of astronomy at ETH Zurich, explains: 'There is a joke in astronomy that' in order to understand the universe, we understand galaxies about radiation, gas and heat. degree, chemical organism and more; anything we cannot explain then we attribute to the magnetic field '' . The formation of magnetic fields in the galaxy is still a mystery. Until now, it was deduced that the galaxies that formed after the Big Bang 13.8 billion years ago had very weak magnetic fields but then increased the exponential magnetic field intensity for several billion years. At least that's what the theory of dynamo is often used to explain the development of magnetic fields - conveying.

Statistical methods for accurate evidence

In Nature, Martin Bernet, Francesco Miniati and Simon Lilly discussed the topic of magnetic fields in young galaxies. The results are surprising: In contrast to the popular dynamo interpretation model, the team was able to demonstrate that even very young galaxies also have strong magnetic fields based on astronomical data analysis methods. available learning as well as newly obtained. Technically, it is difficult and extremely time-consuming to determine the magnetic field strength located billions of light years from Earth. This is probably one reason why the magnetic field has almost never been studied before.

However, by using the Faraday rotation parameter (Faraday Rotation - FR), the magnetic field strength can be deduced from the light polarization in the radio wave field. If linearly polarized light spreads when passing through the magnetized gas cloud, the polarization of the light changes. The variation in the polarity of light depends on the magnitude as well as the strength of the magnetic field . Michael Faraday described this effect for the first time in 1845. The researchers used quasars as radiation sources to determine the magnetic fields of the galaxies in question. Quasars are powerful glowing entities, their radiation can be explained by the existence of a great black hole at the center of the galaxy.

Observation in Chile

To get their analysis, scientists together with Lilly used FR quasar measurements made by astronomer Philipp Kronberg of the University of Toronto. Martin Bernet, a postdoctoral student of Lilly and Miniati, explored the relationship between the Faraday Rotation and the redshift of red crystallization light for 300 of FR measurements. In astronomy, the red shift is used to determine the age and distance of galaxies.

Picture 1 of Young galaxies have surprisingly strong magnetic fields

What makes the magnetic fields of galaxies close to similar to quasars located billions of light years away?Large picture: 'Whirlpool' galaxy;thumbnail: OC-65 quasar.(Photo: mpifr-bonn.mpg.de )

Researchers have formed a hypothesis from the statistical arrangement of the values obtained: 'The observed observational quasar rotation is stronger with a stronger redshift in the long-distance more and can be attributed to the ability to connect with other larger galaxies' . To verify the hypothesis, astronomers selected 76 quintiles from the original Kronberg model and then used a very large telescope (Very Large Telescope - VLT) in Chile to see how much the spectral spectrum is. sugar absorbs magnesium. From previous studies we learned that most galaxies located along the quasar light pathway (light lines between quasars and telescopes) are capable of absorbing magnesium.

So researchers are able to determine how many galaxies lie between our galaxies and quasars and ascertain the galactic magnetic field by comparing the FR value of the line of sight and not. capable of absorbing magnesium. For galactic magnetic fields, calculations give a value of about 10 aGauss; in other words, the magnetic field is about a million times weaker than the Earth's magnetic field. This, though much, corresponds well to the magnetic field value of our galaxy - 'The Milky Way'. The results enabled researchers to prove that young galaxies located far away also have strong and strong magnetic fields.

It was at the time that the universe was only 1/3 the age of today. What comes from the new study contradicts the popular dynamo theory, whereby the magnetic field gradually builds itself exponentially through billions of light-years thanks to regular reinforcement. Lilly explains: 'The magnetic field of a galaxy must be formed much faster during its development than what we have speculated. At that time, long-term equilibrium occurred at a relatively early stage. '

Astronomers are aware of magnetic fields

The scientific community has sometimes been skeptical of bullshit. Kronberg also repeatedly expressed doubts about this existing model during his 30-year FR test. However, there is still a lot of evidence so far. According to Lilly, the latest issue in Nature reveals all the quality of the VLT dollars and is the clear answer to the original question that is rare in astronomy.

Lilly argues: 'I can imagine that the method we just introduced and the combination of the Faraday rotation method and the telescope data like VLT can open the door to new. the universe is far away '.

According to the conclusion of the authors of the Nature paper, the results also make people reconsider the current astronomical practice where magnetic fields are often ignored. Lilly and her team will continue to explore the door they've just opened while searching for the mysteries of the magnetic field. They were allowed to have more time to observe with the VLT telescope. The next step to achieving a more comprehensive understanding of the 'mystery of magnetic fields' will be to increase the quasar and accurately locate the magnetic field in galaxies.

Kinetic theory

The magneto turns mechanical energy into magnetic energy. The dynamo theory is used to explain some entity's magnetic field mechanism in the sky . For large entities such as planets, stars or galaxies, the diamorphic effect occurs if there are disturbed currents and heterogeneous revolutions. The so-called alpha-omega ginseng can generate large magnetic fields, even when the original field is very chaotic.