In String Theory, what is the difference between and open an closed string and what is the significance?

Question

I'm particularly interested in the ability for one to shift to the other and the potential for superimposition...

Answer 1

Well, it's actually the Theory Formally Known as String Theory. It's been replaced by brane, membrane or just plane M theory. It adds a bunch of membranes to the soup. Think of a membrane like a surface (they can actually be 3, 4, 5 dimensional. Open strings are confined to a brane, closed strings can traverse between them.

For argument sake lets put up two walls that are parallel to each other and say that they are membranes. Let's put the universe that we know in one of the branes and put all the particles and forces that we know in it. Let's make all the strings that make up the elementary particles and basic forces (except gravity) that we know open strings. They are stuck to our brane. Think of the ends being stuck to the wall. Lets call the other membrane, the gravity brane and lets say the gravitons are closed strings and originate there. Now lets say that the two membranes ( walls ) are connected by another membrane between them like a slice of bread between them. The slice of bread can be given characteristics such that when a graviton moves from the gravity brane to ours, it's influence greatly weakens.

The basic problem with our understanding of forces is that gravity is about 10^20th weaker than the rest. In this theory, when gravitons are in the gravity brane, they interact as strongly as all the other forces. Since they're closed strings they can migrate and when they migrate to our brane they significantly weaken.

KInd of Buck Rogers stuff I know.

Answer 2

the vast Bang started the extensive outward enlargement of rely we see those days. the enlargement is counteracted via gravity. A closed universe has sufficient rely in it, so as that -finally- gravity will win and rely will initiate imploding returned: the vast Crunch. In an open universe the quantity of rely isn't sufficient to end the enlargement. the present concept is that we are in an open universe, yet slightly. a large type of the mass in our Universe seems to ensue interior the form of darkish rely. they are supposedly, created from debris different than the already accepted ones. String concept predicts the life of such extra beneficial debris.

Answer 3

open string is a string with two endpoints. and closed string is a string with no endpoints. Closed string can be in many shapes, a circle, a triangle or even a rectangle.

i think the rest i have no need to tell you. I myself learnt it from google. It should still be there.