Exploring String Theory: Open and Closed Strings

B
Thread starter PGaccount
Start date Jul 29, 2018
Tags

Shapes String String theory Theory

In summary, open strings can be thought of as world lines, while closed strings can be compared to loops. This concept is similar to the point of view presented in Green, Schwartz, Witten superstring theory volume 2. The image of different string shapes can be found on the first page of a Google search for "open closed string world sheet."

Jul 29, 2018

PGaccount

are open strings like world lines? and closed strings like loops?

Physics news on Phys.org

Jul 29, 2018

Spinnor

Gold Member

Dibujo20150803-world-sheets-open-strings-closed-strings-string-theory-Zwiebach.png

From https://www.google.com/search?safe=...0k1j0i24k1.0.oYFwSZDIBDw#imgrc=Q_zxTiQeY4_0IM:

Aug 23, 2019

PGaccount

Is this the point of view in Green, Schwartz, Witten superstring theory volume 2?

Aug 26, 2019

DEvens

Education Advisor

Gold Member

Heh heh! I wanted to know where that picture of string shapes came from. Clicking on the Google search link produces the first hit being this very page. LOL!

1. What is string theory?

String theory is a theoretical framework in physics that attempts to explain the fundamental nature of the universe by describing everything as tiny, vibrating strings instead of point-like particles. It is a candidate for a theory of everything, as it aims to unify the four fundamental forces of nature: gravity, electromagnetism, strong nuclear force, and weak nuclear force.

2. What are open and closed strings in string theory?

In string theory, open strings are strings with two distinct endpoints, while closed strings are strings with no endpoints, forming a loop. Open strings can vibrate in various modes, while closed strings can only vibrate in one mode. The behavior and interactions of these strings are what give rise to the particles and forces in our universe.

3. How does string theory explain the concept of extra dimensions?

String theory posits that there are more than the four dimensions (three spatial dimensions and one time dimension) that we experience in our daily lives. These extra dimensions are "curled up" and too small for us to observe directly. However, they play a crucial role in the behavior of strings and can help explain various phenomena, such as why gravity is weaker than the other fundamental forces.

4. Is string theory testable?

Currently, string theory is still a theoretical framework and has not been definitively proven or disproven. However, there have been efforts to test some of its predictions, such as the existence of supersymmetric particles, through experiments at the Large Hadron Collider. Ongoing research and advancements in technology may eventually provide evidence for or against string theory.

5. What are some potential implications of string theory?

If string theory is proven to be correct, it could have significant implications for our understanding of the universe. It could potentially reconcile Einstein's theory of general relativity with quantum mechanics, provide a solution to the mystery of dark matter and dark energy, and even lead to the discovery of new particles and forces. It could also have practical applications, such as in the development of new technologies. However, until there is concrete evidence, these implications remain speculative.