Dark Energy
What is dark energy?
RAKESH PANDEY
Dark energy is some kind of energy which is said to exist but scientists know very little details of it. About 14 to 15 billion years ago, when the Big Bang happened, the universe came into existence. The matter formed from huge energy started expanding due to outward force of the Big bang. From the theory of gravity postulated by Einstein, the particles having mass should attract each other and the expansion of the Universe should stop at one point of time.
However from the observations made by the astronomers, it appeared that the rate of expansion has increased after about 7 billion years. This shows that some other force is acting against the gravity which is forcing the expansion of universe instead of contraction. Scientists gave name to this unknown force as the ‘dark energy’.
It is interesting to know that what we see as the matter in the universe in the form of stars, planets, clouds of dust, only forms about 5 per cent of the universe’ mass, rest being dark energy (about 68 per cent) and dark matter (about. 27 per cent).
S P S JAIN
Former Member, Engineering, Indian Railways
Greater Noida
THIS WEEK’S QUESTIONS
Is there any effect of neutrinos when they pass through our body?Bhanu Jamwal, Jandial, Jammu & Kashmir
Why is it very difficult to burn a heap of fresh green leaves but once the leaves dry up they burn easily?
SHARATH CHANDRA
What are gravitational waves?
Chaitanya Vuddanti, Hyderabad