(Please find the audio link on YouTube at the end of the article)
Hello Earthlings !
Do you think that the light : your sun, the stars, the galaxies are the only forms of matter in the of Universe ? All the darkness of the night is just empty space ?
I find your lack of faith disturbing !
All you can see and understand is merely 4% of the Universe !
Let Lord Vader teach you about your 96% Ignorance !
The Universe is basically Dark. Nobody understands it !
You might know about the gravitational force: the force due to which two massive bodies attract each other. This is the same force which keeps earth going around the sun and moon going around the earth.
Have you tried rotating a heavy object by a rope ? The rope gets tighter and tighter as you rotate faster and faster. The rotational motion needs a force, which is the tension in the rope. For rotation of earth around the sun, this force is provided by gravitational force. Gravitational force depends on the mass of the involved objects and the distance between them.
Astronomer Fritz Zwicky discovered that the stars in a cluster of glaxay, called coma cluster were moving much faster than they should be.
[The Coma Cluster]
How can a human know how stars “should” be moving, you ask ? This is the power of Physics ! Physics teaches you the way of the force using which you can calculate the speeds of stars. All you need is masses and the distances of involved objects . The speed at which the stars were moving was much faster. At such speeds the stars should just fly apart, because gravitational force of visible mass is not strong enough to hold them together.
Astronomer Vera Rubin by her meticulous and very precise measurements of rotation curves of galaxies, confirmed that the visible mass is not enough to account for the observed speed of stars in the rotating galaxy. Let me digress a bit to tell you a bitter truth. You humans, because of your ignorance of deeper ideas of universe, suffer from the disease of gender discrimination against women, which makes you lose brilliance like hers. The Force knows no such difference. She is one with the FORCE. You better start treating every child of yours with respect and honor and nurture the scientist in each of them if you want a chance to the greatness in the cosmos,
[Vera Rubin working with her measuring engine in 1974]
[Rotation curve of a spiral galaxy, Triangulum Galaxy . The blue and yellow dots show what is observed speed on y-axis in km/s and the dashed line shows what are possible speeds if we only consider the visible matter. You can clearly see observed speeds are much higher than they should be. The x-axis is distance from center of galaxy in light years, 1 light year distance traveled by light in one year. 1ly ~ 10 trillion km]
(Image Source: https://en.wikipedia.org/wiki/Galaxy_rotation_curve)
So now you know that the stars are moving so fast that they should fly apart. What keeps the stars together in the galaxy ? THE DARK MATTER! The Matter which you cannot see because light does not interact with it, but it exerts the gravitational force because it has mass. To explain the observed speed of stars, there must be a lot of dark matter. More than six times the ordinary matter.
Realize the importance of Dark Matter! It is responsible to keep the stars, including your sun, from flying apart! It binds the Universe together. The very existence of the Universe in its current form is due to DARK MATTER! There is so much Dark Matter in our Universe that it is passing right through you at this instant.
What can Dark Matter possibly be ? No one knows, but there are various theories and the search for the Dark Matter is ON! I will enlighten you about some possible candidates:
Weakly Interacting Massive Particles (WIMPs): These particles interact “weakly” hence may miss out on interaction with light and appear dark. But they do have mass so they can form dark matter. Primary candidates are neutrinos, axions and neutralinos. If these names scare you, contact the members of this blog, trying to write my script and they can point you to more resources.
MAssive Compact Halo Objects (MACHOs): They are objects which are ordinary matter, but they do not shine like stars to give off light, hence they appear dark and can explain the dark matter. The candidates are black holes, neutron stars or brown dwarf stars. Again, if these names scare you, contact the members of this blog. You must take into account though there is no evidence that the Universe has enough MACHOs to explain all the missing mass.
Scientists all around are trying to detect the Dark Matter. One set of schemes is to directly detect it by using very sensitive detectors buried deep underground, to avoid noise from other sources. Another set of schemes is to produce the Dark Matter itself by colliding high energy particles, like in Large Hadron Collider (LHC) !
I hope you will soon understand the mysteries of Dark Matter and come in terms with the Dark Side.
See you next time !
May The Force be with You !