GRAVITATIONAL WAVES
What are gravitational waves?
CHAITANYA VUDDANTI, Hyderabad
While Sir Isaac Newton visualised gravitational force as a pulling force between objects, Albert Einstein opined it to be a pushing force due to the curvature of four dimensional spacetime fabric. The curvature of spacetime stems from the dent heavy objects produce on spacetime fabric which can be compared to the dent one could see on a plastic sheet when a massive ball is placed.
Mass in motion is the source of ripples of curved spacetime that propagate away at the speed of light. These propagating ripples in spacetime curvature are called gravitational waves that arise as a natural consequence to hold the general theory of relativity proposed by Einstein.
It is well known that accelerated electric charges produce electromagnetic waves. In a similar way, an accelerated mass produces gravitational waves. Although it is a classical effect, the strength of this effect is very small. For instance, the gravitational waves emitted by a vibrating electric charge are about a trillion trillion trillion times weaker than the electromagnetic waves emitted by the same electric charge.
Although, physics supports the existence of gravitational waves, the strength of such waves even due to astronomically heavy bodies is awfully weak to be detected. In spite of technological difficulties in directly detecting the existence of the gravitational waves, attempts have been on over the years as detecting them could help unravel the secrets of nature, including the birth of our universe itself.
Dr. P. RAMESH BABU, Professor of Physics
VIT University, Vellore, Tamil Nadu
THIS WEEK’S QUESTIONS
Why is the number of meteorites striking the moon's surface quite large whereas very few reach the earth's surface?
Sharath Chandra
How do we hear sounds from internal organs
(like stomach)?
Balagangadharan, Pollachi, Tamil Nadu
What is the difference between certain medicines in tablet form and certain medicines in capsule form though both are taken orally?
T.N.Sama Rao, Thiruninravur, Tamil Nadu
Why do we experience a tingling feeling in our hands or feet when we keep them in the same place for a long time?
K.Vaishnavi, Sivakasi, Tamil Nadu
