Question

Heya!!

# Contact Quality Required #

Question no .1.

What is gravity? (describe in full)

Question no .2.

How did the universe begin?

Thanks.. :))

Answer 1

1. GRAVITY:-

Newton described gravity as the force which acts between every particles in the universe. He described that gravity is one of the fundamental force of nature.

He said every particles in the universe attracts each other by a force which he called it gravity which is directly proportional to the product of their masses and inversely proportional to the square of distance between them but his assumptions was wrong. even he couldn't describe it's mechanism.
Newton's law of gravitation is wrong, because it cannot account for a number of phenomena we observe in the universe around us, such as the perhelion advance of Mercury, or the bending of starlight near the limb of the Sun. Newtonian gravitation is an approximation to a broader theory, the general theory of relativity which is not, as far as we know today, in error. In the limit of low gravitational field strengths and low velocities, general relativity and Newtonian gravitation theory are indistinguishable.any theory is provisional in the sense that it is a hypothesis. it doesn't matter how many times the result of experiment agrees with the theory's prediction. On the other hand if you find even a single phenomenon of which result theory can't predict, the theory will be proved wrong.

Newtons laws are correct for speeds < 0.01c(c=speed of light) but once we cross this border, Einsteins Special Relativity must be used. The Einstein's theory of gravitation, the theory of general relativity, is more accurate than Newton's law of gravitation. Experimentally, Newton's law of gravitation has been proved wrong due to for example the anomalous perihelion precession of Mercury, which matches instead with Einstein's theory of gravity.

Now what is Einstein's theory of gravity.
He said gravity is not a force at all. he said that acceleration and gravity are the same things. he also described the mechanism of gravity. according to him gravity is just a effect of distortion of space time due to mass or energy.
A massive object generates a gravitational field by warping the geometry of the surroundingspacetime.
Spacetime in the presence of masses is curved.he said matter tells space time how to curve and space time tells matter how to move.

How gravity works?
as Einstein described that when any mass distorts the space time it generates a gravitational field.

Quantum description of gravity:

Gravity is just the exchange of bosons named as graviton according to quantum mechanics.
But, I have a counter agreement against this theory.
When we think of gravity as an exchange of bosons, there are problems. We have said that you can think of exchange of graviton between matter particle and earth particle. but because all these gravitons Are also exchanging graviton among themselves mathematically this is messy.
According to me it is an illusion or phenomenon created by all the forces of nature when they work together.

This is just a preview of my research on gravitation. Uh may check out the whole here:
exoticexplorer.blogspot.in

2. HOW DID THE UNIVERSE START:-

One of the most interesting questions considered by astrophysicists deals with the start of our universe. Indeed, there is a great deal of speculation on the subject, with different theories about how the universe began, and what may have existed before the universe came into being.

Several prominent astrophysicists around the world are interested in answering these questions. In one paper, No-Boundary Measure of the Universe, published, Published mainly by James Hartle, Stephen Hawking and Thomas Hertog, they calculated the probabilities that the no-boundary wave function predicts in terms of classical space-time possibilities.

This answer is not complete due to the word limit on a answer. So, I would be writing the rest in the comments. Be sure to check that out too ;)

Hope This Helps :)

Answer 2

hye

====================================

what is gravity

Gravity is a force which tries to pull two objects toward each other. Anything which has mass also has a gravitational pull.

 The more massive an object is, the stronger its gravitational pull is
. Earth's gravity is what keeps you on the ground and what causes objects to fall.

Gravity is what holds the planets in orbit around the Sun and what keeps the Moon in orbit around Earth.

The closer you are to an object, the stronger its gravitational pull is.
 Gravity is what gives you weight.

It is the force that pulls on all of the mass in your body.

who found it:_

Newton realised that every object in the Universe attracts every other object in the Universe. Even an apple tugs slightly at everything around it.


why is not gravity in space:-?

actually ,there is some amount of gravity in space

 
gravity is not so obvious in space is because objects tend to orbit planets instead of hitting them.

 Orbiting just means that an object falls towards a planet due to gravity and continually misses it.

 Because space is so large and planets are so small by comparison, it's actually very hard to hit planets.

so only If a spaceship travels far enough from Earth, it will eventually escape the planet’s pull completely. 

----------------------------


2) How did the universe begin?

According to ous standard theory our universe sprang into existence as singularity around 13.7 billion years ago.

 Singularity and zones which defy our current understanding of physics.

 They are thought to exist at core of black holes. The pressure are thought to be intense that infinite matter is acutally squished into infinite density

. After its initial appearance it apparently inflated expanded and cooled. It continues to expand and cool to this day and we are inside of it: incredible creatures living on a unique planet, circling a beautiful star clustered together with several hundred billion other stars in a galaxy soaring through the cosmos, all of which is inside of an expanding universe that began as an infinitesimal singularity which appeared out of nowhere for reasons unknown. 

this is also big bang thorey

=================
hope i thelps u ..........