Late times of WWI Albert Einstein’s General Theory of Relativity were published. According to the theory,
”The mass/gravitational force exerted would magnify as a lens deflecting light from straight line to curvature arcs.”
In1933 Fritz Zwicky was focusing on coma cluster located 300 million light years away. He observed the galaxies moving far too fast with the other galaxies’ gravity it should have leaded a normal orbit in 1000 km/sec, which was getting ripped. Thus it needed more gravity but what created it was unknown. He concluded that there was ‘dark matter’ which gravitationally bound the coma clusters.
Fritz Zwicky
In 1963 Vera Rubin stepped in with her collaborated Kent Forte to analyse how the galaxies spin. She undertook precautious and accurate observations when she concluded that the galaxy was like the solar system with more gravity in the center and matter was expected to fall from the edge of the galaxy. But she found that the RPM (Rotation per Minute) was the same along the edges and the center. Thus the Zwicky’s dark matter came to spotlight as it seemed to provide gravitational help in maintaining the same mass, gravity and speed throughout. Then they turned towards gravitational lensing.
Vera Rubin
Quasars are extremely bright and distant objects powered by matter falling into super massive black holes, releasing intense energy and radiation.
In 1979 Juan Quasar named q0957+561 gave a puzzle. They noticed two quasars identical and close to each other. They realized it was huge gravitational because of an identical copy of the same quasar was seen. The distant galaxies were magnified by this phenomenon. When the mass was calculated using the magnitude of distortion it was found to have more mass than the visible objects.
For many years humanity’s creativity led to the discovery or recognition of constellations. But beyond this simple structure lays every complex clusters. It contained billions of stars and galaxies.
In1970’s astronomers came up with an idea of charting up the location of the galaxies. Their thought was clear a measurement of cosmic speed due to the expansion of the universe reveals a galaxy’s distance but it means to measure individual lights of the galaxies which was created by CFA Redshift survey based on Harvard University’s center for astrophysics. It revealed that the cluster of galaxies were linked with filaments present in the structure were empty space called voids.
By Mid 1990s two astronomers John Hucra and Maragaret Geller analysed and formed a result for the CIA survey using the analysis of eighteen thousand galaxies. But then raised the question, where did these cosmic structure come from?
John Hucra Margaret Geller
Astronomers knew during the Big Bang helium and hydrogen gases forged together and smoothly spread but underlying that was dark matter.
The explosion which happened many billion years ago created ripples in space time creating slightly more dense regions. The slightly denser regions formed attraction with the help of that dark matter present at that time. Gases pooled, chunks of helium and hydrogen out of the clouds. From this cooling and collapsing gases was formed the first stars. Without dark matter any of these would not be possible and it was that as the universe expanded the dark matter kept on increasing in quantity.
When synthetic universes were created for studies by scientist the results were surprising as the galaxies which were surrounded by more dark matter which had the capability of immense gravity to form galaxies. Scientists predicted that the dark matter had to have some particular property which moved sluggishly.
Although this is all we have understood about the dark matter, understanding it deeply can even break the laws of physics we have but everything is an opportunity for the mankind to learn and prosper. This 27% of the universe is a different realm compared to ours.
Tharun R.
Batch 30