What is Dark matter?
Dark matter is a hypothetical invisible mass that is thought to be responsible for adding gravity to galaxies and other celestial bodies. Dark matter makes up about 27% of the universe, while visible matter (like stars and galaxies) only accounts for 5%. Dark matter is called “dark” because it doesn’t interact with electromagnetic force, making it very hard to detect. The only way it can be detected is through its gravitational effects.
The rest of the universe, about 68%, is made up of a mysterious substance called dark energy. Dark energy is also a hypothetical invisible force, much like dark matter, but it’s believed to be responsible for the accelerating expansion of the universe. Like dark matter, dark energy cannot be directly detected, but its existence is inferred based on its effects on the motion of galaxies and other celestial bodies.
To detect dark matter, astronomers used a special type of radiation called the Cosmic Microwave Background (CMB). They observed how the CMB radiation interacts with the gravitational field of massive objects such as galaxy clusters and lumps of dark matter. The gravitational field of these objects bends and distorts the light that passes through them, and this bending of light helps in detecting dark matter. Essentially, by observing how the CMB radiation is distorted by these massive objects, astronomers can map out the distribution of dark matter in the universe.
Astronomers have recently created the most detailed map of dark matter to date, using data from the universe’s very first light (known as the CMB radiation). This new map shows the enormous tendrils of dark matter that formed soon after the Big Bang, and the shapes of these tendrils match those predicted by Einstein’s theory of general relativity/gravity.
This is a significant finding because it contradicts previous dark matter maps that suggested the cosmic web was less clumpy than Einstein’s theory predicted. Einstein’s theory of gravity, has been the subject of an ongoing debate in cosmology.
Some scientists have proposed alternative theories of gravity that might better explain the observed phenomena, while others argue that general relativity is still the best explanation we have.
One of the main challenges to general relativity is the phenomenon of dark matter. The theory of general relativity predicts the existence of dark matter, but it has been difficult to directly observe or detect. Previous maps of dark matter had suggested that it was less clumpy than predicted by general relativity, which led to some doubts about the theory’s validity.
The map was created using the Atacama Cosmology Telescope, located in the Atacama Desert of northern Chile. Its goal is to study how the universe began, what it is made of, and how it evolved to its current state.
The importance of dark matter lies in its gravitational force, which prevents stars in our Milky Way from flying apart. Understanding dark matter and its properties is key to understanding the universe’s formation and evolution