Why does gravity pull us down and not up?

Every time we jump, we experience gravity. It pulls us back down to the ground. Without gravity, we'd float off into the atmosphere along with all of the other matter on Earth. Gravity is the reason things with mass or energy are attracted to each other. That is why apples fall towards the ground and planets orbit stars.  

There are two theories that are the most common and widely held (if somewhat incomplete) explanations of gravity. 

• Isaac Newton defined gravity as a force -- one that attracts objects to one another.  
• Albert Einstein said gravity is a result of the curvature of space-time. 

Here, we will discuss Einstein’s theory in depth to find out why gravity pulls two forms of matter together instead of pushing them apart. According to Einstein, gravity isn’t a force at all. Instead, it is a distortion in the shape of space-time. According to him, the reason why gravity pulls us towards the ground is this: All objects with mass, like the Earth, actually bend and curve the fabric of the universe, called spacetime. That curvature is what we feel as gravity. 

What is space-time? 
Space-time is the combination of the three dimensions of space – length, width and height – combined with the fourth dimension – time. Space and time are connected. If we move really fast through space, time slows down for us compared to someone who is moving slowly.  

The Theory of Relativity 
Gravity is the idea that objects in the universe are attracted to each other because space-time is bent and curved. Imagine the surface of a trampoline. If there is nothing on it, it is flat. When we put some weight on it, it creates a valley with the mass at the centre. Another lighter object placed on the trampoline will naturally roll towards the heavier object. This distortion of the trampoline’s surface is similar to the distortion in spacetime that pulls two objects together. As far as scientists know, matter always makes gravity wells and not gravity hills. 

However, what Einstein’s theory doesn’t explain is why is matter attracted toward each other and not pushed away from each other, the way opposite poles of two magnets attract but corresponding ones repel. Scientists can imagine things made of exotic matter or energy that would cause gravity to push you off into space, but so far, no one has found anything that could cause gravity to push you away from Earth.