My dad has been trying to convince me that gravity isn't real. Or that it's not what we think. His ideas are wrong, and I will never convince him otherwise because he thinks he's way smarter than he is. Anyway. I only learned what gravity was a few months ago myself. Maybe a year. But I think it's awesome. I think this is the video that originally blew my mind. By Professor Dave on YouTube. Okay this wasn't the original video, but now I understand it way better. [Special Relativity Part 1: From Galileo to Einstein](https://www.youtube.com/watch?v=rBmYUEnafok&list=PLybg94GvOJ9FAFBqQGf5-4YbfKpWbJtGn&index=9) In the land of classical physics, [[Isaac Newton]] created the first formulas for gravity by inventing [[Calculus]]. Or discovering it, rather. He called it "Action at a distance." Didn't know what it was but he could use it to predict the sky and movement of all objects. And they worked, really well. For a really long time! But then [[Albert Einstein|Einstein]] comes along with his new theories, the theory of [[Special Relativity]] and [[General Relativity]]. They were necessary because while newtonian physics worked for most practical applications, the calculations seemed to be a bit off when it came to calculating things that were very small, or moving very fast. Like lightspeed fast. And very small meant like subatomic particles. And that's because of Reference Frames. And the main conclusion of Special Relativity is that TIME IS RELATIVE! Time is not constant. Different objects experience time at a different rate. How do we know that? Because of experiments, and math. The [[speed of light]] is a fundamental law of physics. It's a universal speed limit. We had to rethink our understanding of time in order to account for our observations from Special Relativity. Okay I'm pretty sure THIS is the video I meant. General Relativity! But I'm gonna finish the series on special real quick. [General Relativity: The Curvature of Spacetime](https://www.youtube.com/watch?v=R7V3koyL7Mc&list=PLybg94GvOJ9FAFBqQGf5-4YbfKpWbJtGn&index=12) ![[23-01-09 physics basically.png]] [[Classical Mechanics]] emerges from [[Quantum Mechanics]] as objects attain more mass, and also emerges from [[Relativistic Mechanics]] as fast objects slow down. When we start considering things that are both VERY SMALL AND VERY FAST, we get into the [[Quantum Field Theory]], where a lot of exciting new physics is happening. Like in the [[Large Hadron Collider]]. what is gravity >[!NOTE] ChatGPT > Gravity is the force that attracts two objects with mass towards each other. It is the reason you stay on the ground and the Earth orbits the sun. Gravity is what gives weight to physical objects. > > The strength of the gravitational force between two objects depends on their masses and the distance between them. The more massive an object is, the stronger its gravitational pull. The closer two objects are, the stronger the gravitational force between them. > > Gravity is one of the fundamental forces of the universe and is described by the theory of general relativity. The gravitational force is always attractive, but it becomes weaker with distance. what is gravity shaped like >[!NOTE] ChatGPT > Gravity does not have a shape in the traditional sense. It is a force that acts between two objects with mass, pulling them towards each other. > > However, the effects of gravity can be represented by a gravitational field, which is a mathematical model that can be used to describe the strength and direction of the gravitational force at different points in space. In this sense, you could say that the shape of gravity is determined by the distribution of mass and energy in the universe, and how this affects the curvature of space-time. > > According to the theory of general relativity, massive objects cause space-time to curve, and this curvature determines the path that other objects will follow under the influence of gravity. So you could say that the shape of gravity is determined by the shape of space-time, which is influenced by the distribution of mass and energy in the universe.