Sunday, July 11, 2021

Einstein's General Relativity

 

Scientists say that 13.8 billion years back, there was a Big Bang explosion from a single point which has created our expanding Universe.

The mystics reminded them that this was pretty close to the writings in the Rig Veda (1500-2000 BC), the oldest Hindu book of knowledge “There was neither non-existence nor existence then; there was neither the realm of space nor the sky which is beyond. What stirred? Where?” 

This stirring started the game "Leela" called existence. A single golden seed called Hiranyagarbha exploded to begin the formation of our cosmos. Like the acorn has the potential to create a huge Oak tree, so too, the seed Hiranyagarbha had the potential of the Universe.

The Big Bang 13.8 billion years ago and the expansion of the Universe




Mankind has always been fascinated with the study of the cosmos that is so mysterious, vast and unfathomable. In 1609, Galileo made his rudimentary 37mm dia telescope. Since then, scientists have been using rapidly evolving tools and technology to study the Space outside. The James Webb Space Telescope (JWST) is now being made by NASA, which is thousands of times more powerful than earlier telescopes. It will give scientists the opportunity to clearly 'see' cosmic events, as they happen. The Hubble Telescope has been travelling on the Earth’s orbit, while JWST will go all the way out to locations that are 1.5 million kms away and follow the orbit of the Sun. The Universe is revealing more and more. 


Soon the galaxy will open up for more intense scrutiny

All this while, a genius called Einstein was thinking, “Events, even the minutest, take place at specific locations and at certain time. For example, a simple event like brushing one’s teeth or having a bath happens by occupying a certain space and within a particular time line. Thus every event has four dimensions – the three dimensions of space (length, height and depth) and the fourth dimension of time.Our Universe is a space-time continuum that is constantly expanding, thus creating a three dimensional space over a period of 13.8 billion years”. This space and time are interwoven into a single continuum known as space-time, which can be visualised a flat grid. 

In 1915 Einstein realized that this flat space-time grid does not consider the gravitational force of large objects. Massive objects in space like the earth, planets, sun, stars caused a distortion in space-time as the gravity of that object curves the grid. Imagine setting a large cricket ball in the center of a trampoline. The ball would press down into the fabric, causing it to dimple. A marble rolled around the edge would spiral inward toward the body, pulled in much the same way that the gravity of a planet pulls at rocks in space.This is the essence of Einstein's General Theory of Relativity.


Image result for black hole sketch

The gravitational force in some objects in the Universe becomes so powerful and pulls down the space-time grid to such an extent that creates “Black Holes” that are so deep and dark that, even light cannot get out. Celestial bodies including stars collapse in these black holes. Because no light can get out, people can't see black holes. They are invisible. Black holes can be big or small, ranging from less than an atom to “supermassive” that are more than 1 million suns together.



Suppose that there is a star about 20 times more massive than the Sun. When this star runs out of fuel, the gravity will overwhelm the natural pressure that the star maintains to keep its shape stable. As the pressure from nuclear reactions collapse, gravity will violently overwhelm and collapse the core. Other layers will be flung into space called supernova. The remaining core collapses into a gravitational singularity- a one-dimensional point which contains infinite mass in an infinitely small space, leading to tremendous energy. The gravity becomes infinite and space-time curves infinitely, and where the laws of physics, as we know them, cease to operate. 





A mention of the black holes was also made in the ancient Indian scripture, Mandukya Upanishad (400 BC) which talks about Vishwaruchi that absorbs everything in the Universe - black hole.
Vedic cosmology has so many eerie parallels with the Western knowledge of the Universe, that Nobel Prize winner and nuclear scientist Niels Bohr once wrote, “I go into the Upanishads to ask questions.” Thus, scientists have started coming round to the view that the mystics were on the right track. They have stopped smirking and their minds have opened to the possibility that the Rishis could be right.

The Puranas- spiritual texts of the mystics (500 to 1500 BC), describes the many worlds or parallel Universes that exist in different planes. It is now that science has started accepting that there could be parallel Universes called Multiverse. “There are vibrations of different Universes right here, right now. We’re just not in tune with it. There are probably other parallel Universes in this living room – this is modern physics. This is the modern interpretation of quantum theory, that many worlds represent reality” says Michio Kaku, one of the greatest modern scientists.



Maybe the time has come for the mystics to assert themselves. 

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