Wrapping my brain around branes

[Team Bobo]

New to the forum. What a great resource. I just started learning a bit about string theory and naturally I've developed a few questions. The first thing I'm trying understand involves the idea that a string with enough energy could grow to a membrane of immense size up to the size of a universe. It follows that our entire universe may be a membrane. So far so good.

Here is the problem. If our universe is a membrane (stretched string) and a string is the smallest "element/particle/whatever you call it" then how can anything exist within that membrane?

 

[AndyW]

Hello and welcome to the forum! I am glad to hear that you are interested in string theory and have some questions about it. Let me try to address your concern about how anything can exist within a membrane universe.

First, it is important to understand that the idea of our universe being a membrane or "brane" is just one aspect of string theory. String theory is a theoretical framework that attempts to unify all the fundamental forces and particles in our universe. It proposes that the most basic building blocks of our universe are not point-like particles, but tiny one-dimensional strings. These strings vibrate at different frequencies, giving rise to different particles with different properties.

Now, going back to the idea of a brane universe, it is true that string theory suggests that our universe could exist on a higher-dimensional brane. However, this does not mean that everything within our universe is made up of strings. In fact, the strings themselves are so small that they are not directly observable. Instead, they give rise to the particles and forces that we can observe.

Furthermore, the concept of a brane universe is just a mathematical description and does not necessarily mean that our universe is literally a stretched membrane. It is just a way to visualize the idea that our universe could exist on a higher-dimensional brane.

So, to answer your question, even if our universe is a brane, it does not mean that everything within it has to be made up of strings. The strings are just the underlying fundamental building blocks that give rise to the particles and forces that we observe. I hope this helps to clarify your understanding of string theory. Keep exploring and asking questions!