Cosmology

Three roads to Dark matter : A journey in search of dark matter mystery

“The job of physics is not to invent things we cannot see to explain things we can see , but to figure out how to see what we cannot see”. 

Pioneering work of the American astronomer Vera Rubin and her colleagues in the early 1970s gave a new direction to understanding of universe . By observing stars and hot gases that ever farther from centre of galaxy , Rubin determined that these regions were moving much faster than they should have been if the gravitational force driving their movement was due to mass of all the observed objects in galaxy . Due to her work , it eventually became clear to cosmologists that the only way to explain this motion was to posit the existence of significantly more mass in our galaxy than one could account for by adding up the mass of all of this hot gas and stars .

It is easy to imagine way to hide protons and neutrons ( snowballs , planets ,…….none of them shine )  and predict that as many protons and neutrons lie in dark object as visible objects . However , when we add up how much “dark matter” has to exist to explain the motion of material in our galaxy , we find that the ratio of total matter to visible matter is not 2 or 1 , but but closer to 10 to 1 . If this is not a mistake , then the dark matter can’t be made if proton of neutrons . There aren’t just enough of them.

This implied three new lines of research that could fundamentally reilluminate the reality .

1) If these particles were created in the big bang , like the light elements , then we should able to use ideas about the forces that governs the interactions of elementary particles ( instead of the interactions of nuclei relevent to determine elemental abundance ) to estimate the abundance of possible exotic new particles in the universe today .

2) It might be possible to derive the total abundance of dark matter in the universe on the basis of theoretical ideas in particle physics , or it might be possible to propose new experiments to detect dark matter — either of which could tell us how much total matter there is and hence what the geometry of our universe . Each new elementary particle candidate for dark matter suggest new possibilities  for experiments to detect directly the dark matter particles parading throughout the galaxy by building devices on Earth to detect them as the Earth intercepts their motion through space . Instead of using telescopes to search faraway objects , if the dark matter are in diffuse bunches permeating the entire galaxy , they are here with us now and terrestrial detectors might reveal their presence .

3) If we could determine the nature of the dark matter , and in abundance , we might be able to determine how the universe will end .

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I am science enthusiast and I love to write blogs for students and youths who love science. I have deep interest in astronomy and cosmology. I believe that science is most effective tool to serve humankind. .