Hydrogen may be the most abundant element in the cosmos, but scientists are now using it for a unique purpose.
The faint radio glow of hydrogen in the distant past of the universe has provided a beacon of hope for unraveling the nature of the mysterious "dark energy" that is the driving force behind the accelerating expansion of the universe.
The new approach, which came to the fore with the discovery of this glow by scientists working for the "Canadian Hydrogen Density Mapping Experiment" (CHIME) project, not only offers a faster and much cheaper way to study dark energy, but also represents a major milestone for CHIME.
The CHIME instrument was specifically designed to investigate dark energy and its pervasive influence.
For about 25 years, scientists have accepted that the expansion rate of the universe is being accelerated by a mysterious force called "dark energy". This view is based on supernova observations used to measure distances to distant galaxies and was crowned with the Nobel Prize in Physics in 2011.
Dark energy makes up about 70 percent of our universe and is thought to drive the growth of the cosmos following the Big Bang 13.8 billion years ago. However, it remains unclear where exactly this mysterious power comes from.
How and when the world will end has been a matter of curiosity for centuries. Scientists consider several possibilities. The "Big Crunch" theory, in which the universe collapsed into itself as dark energy began to run out, was put forward. It is estimated that the first signs of the Big Crunch will be in the sky.
Experts suggest that at the end of this process, the universe itself will turn into a single huge fireball, all living things will perish, and time and space will be completely erased from existence.
Dark energy, the mysterious force accelerating the expansion of the universe, is a “problematic” issue for scientists because it began acting on the fabric of space soon after the expansion triggered by the Big Bang stopped.
According to the example on Space.com, this is like pushing a child on a swing, watching it stop, and then the swing starts moving again without any pushing. In fact, the swing begins to swing faster and faster. Researchers are like parents trying to figure out where this phantom push on the swing is coming from and how it will proceed.
If this pushing on the swing continues, the child may be thrown into the bushes. In space, the strengthening of dark energy could also lead to the cold death of the cosmos and even a "Big Rip" scenario in which space is torn apart.
Alternatively, if dark energy weakened and allowed gravity to take over again, the universe could collapse in on itself, resulting in a "Great Crunch" in which the universe was compressed into a singularity like the beginning of time.
"Hydrogen is the most common element in the universe and is the raw material from which stars are formed." "Its faint radio emission acts like a cosmic tracker, revealing how matter is distributed across space," said scientist Arnab Chakraborty, a member of the CHIME team. he said.
CHIME has now shown that it can map the radioluminescence of hydrogen entirely on its own, and the research team has begun to take steps in this direction, using only a tiny fraction of the existing CHIME data.
Using 94 nightly observations from 2019, scientists managed to detect a hydrogen signal when the universe was only 5 billion years old.
"Our data indicate that roughly 2 percent of the hydrogen in the universe at that time was in neutral atomic form, which is highly consistent with other measurements. By measuring how this hydrogen is distributed and clustered, CHIME gives us a new way to test our understanding of how galaxies form and evolve," said CHIME fellow Shabbir Shaikh of Arizona State University. he said.
CHIME has collected 7 years of data so far, and the research team hopes to study the distribution of hydrogen back up to 3 billion years after the Big Bang.
