NSS - Mumbai Blogs

Albert Einstein, in his theory of General Relativity, proposed that Gravity is not just a force that attracts the object. Gravity is responsible for making ripples, called gravitational waves, in the spacetime fabric. These waves can be a great medium to unveil various things in space that we think don't exist.    Let's dive deep into this topic and understand what exactly gravitational waves are and how they work. What Are Gravitational Waves?  Two massive bodies creating ripples in spacetime fabric| Source : Scitechdaily.com Gravitational waves are invisible ripples or disturbances in spacetime fabric when objects move at very high speeds. But what are these ripples? The answer is directly linked to gravity. Gravity is a force that bends the spacetime curvature . Imagine that space is a rubber sheet and every massive object will cause that rubber sheet to bend. The larger the mass of the body, the larger the depression, and hence, the larger the gravitational pul...

Illustration of Black Hole B lack holes are one of the most cryptic objects in the Universe. Even after 100 years of its theoretical prediction by Einstein’s General Theory of Relativity, scant knowledge about these gravitationally massive objects. Black holes can be of many types Stellar, Intermediate, Supermassive, Miniature and Primordial Black holes. All the theoretical predictions confirmed observationally to date are related to Stellar Black holes. So what precisely are Primordial Black holes? How were they formed? What are the Observational constraints on them? And why are they considered significant for the advancement of Modern Cosmology?  In 1971, Stephen Hawking propounded that when the age of the Universe was less than a second, excessively dense regions in the Universe underwent gravitational collapse and directly formed black holes. These Black holes were known as Primordial Black holes (PBHs). Like Stellar Black holes, they do not originate from the death of a star b...

Gravitational Lensing Visualization           In the early 1900s the great German physicist Albert Einstein gave his groundbreaking theory of relativity. In the theory, he predicted that space and time is not what we had always perceived, rather, it is a 4-dimensional net-a fabric of spacetime. This fabric bent around any object existing in the fabric. The distortion increased near massive objects and was negligible around tiny bodies like us. This gave rise to a new concept of gravity. For generations gravity was considered to be the weakest of all the fundamental forces and was considered to be an attractive force between two masses. Now according to Einstein’s theory, gravity was causing a spacetime distortion, which was the new reason to explain the revolution of planets around massive bodies like sun.  Light has been a mystery since forever, but some properties were absolutely right then and are true even now. For example: light travels in straig...