Can someone explain every points of the Theory of Relativity?

Answer 1

You're going to have to be more specific. Based on the question you asked, I'm assuming you want the entire mathematical breakdown - which is pretty difficult to explain on a site such as this. If you have more questions after I explain, shoot me an e-mail and I'll give you more details.

Essentially, the whole basis of Relativity is that the Newtonian view of the universe is incomplete. Newton says that gravity is a force which pulls things of smaller mass towards things of larger mass. Relativity explains this as a curvature in the "fabric" of space-time. But I'm getting ahead of myself. Let's start at the beginning...

We commonly view the universe as 3-dimensional. In other words, everything we see has 3 measurable dimensions (height, width, and depth). We therefore refer to space as 3D. Relativity states that there's actually a fourth dimension. You cannot talk about space without including time. Therefore, we refer to this four-dimensional data-set as "space-time." An example of this would be to look at a star. From earth, you see a star that is a certain distance away. That distance can be explained in three dimensions. However, the image we're seeing is also based on the distance to the star. We'll use our sun as an example. The sun is about 1.5x10^8 km away (which equals about 8 light minutes). This distance means that the light from the sun that's hitting the earth right now left the sun 8 minutes ago. If we expand this distance further to a star like Alpha Centauri (4.37 light years) means that the star we see in the night sky is actually 4.37 years older than it looks. We actually can use this technique to estimate the age of the universe...but that's another subject entirely. What you should take away from this paragraph is that space-time is a four-dimensional entity.

Again, Relativity states that the more mass an object has, the greater the "warp" it creates in the fabric of space-time. Think of the universe as a giant trampoline. Imagine placing a Bowling ball in the center of the trampoline and watch the fabric warp. Imagine this warp represents the effect that our sun has on the solar system. Now take a Golf ball and roll it on the trampoline. You'll see it curve around the fabric a bit before quickly rotating towards the center (or flying off the trampoline, depending on how hard you roll it). This represents the effect of orbits. Now, we all know that the earth isn't falling into the sun. What the planets are doing is orbiting at just the right speed to keep it from fall into the center of the "trampoline" or flying off of it.

Now, how can any of this be proven? Well, they devised a clever way to prove this back in the early/mid 1900s. The theory stated that not even light could escape the effects gravity had on the fabric of space-time. During a solar eclipse, the moon is placed between the sun and the earth. An experiment was conducted to photograph the sun during a solar eclipse...but they weren't really looking at the sun. The hypothesis was that a star located directly behind the sun would be visible during a solar eclipse because the light would have to travel around the warp created by the sun's gravity. The experiment was a success and overnight, Einstein became a world-renowned physicist for disproving Newton's view of the universe.

That's the basic principle of relativity. I'm not sure if you wanted me to get into all of the equations and derivations (i.e. explaining the whole E=mc^2 thing, which actually deals with mass-energy equivalence...basically combining "conservation of mass" with "conservation of energy") but if you'd like more information, just shoot me an e-mail at jimradio603@gmail.com.