Dimentional reduction: branworld or Yau-calibi manifolds?

[ensabah6]

string theorists, there are two approaches to reducing 11 dimensions to 4, they are large and we are stuck on one, or they are compactified, too small to see. Which approach makes the most contact with physics?

Is it possible to have 1-2 large dimensions and a 4-folded Yau-Calbi space?

String theory has it to determine which scenario produces physics of our world -- large extra dimensions or small ones?

 

[Coin]

I would like to tack on another question to ensabah's:

Is there any context in which the "4 normal dimensions + 6D calabi yau manifold" approach and the "10d large dimensions but everything's stuck on branes" approach are dual or mathematically equivalent?

 

[Entropia]

I would like to provide a response to the content regarding dimensional reduction and the two approaches proposed by string theorists. Firstly, it is important to note that the concept of extra dimensions beyond the four dimensions of space and time is a theoretical concept that has yet to be proven by empirical evidence. However, string theory provides a potential framework for understanding these extra dimensions.

One of the main challenges in string theory is the problem of dimensional reduction, where the theory predicts 11 dimensions but we only observe four in our physical world. The two approaches mentioned - large extra dimensions and compactified dimensions - are both valid and have been extensively studied by researchers. However, it is not clear which approach makes the most contact with physics as both have their own strengths and limitations.

The large extra dimensions approach suggests that the extra dimensions are macroscopic in size, and we are simply unable to detect them due to their large scale. This approach has gained popularity due to its simplicity and potential to solve some long-standing problems in physics, such as the hierarchy problem. However, it also faces challenges in explaining why we do not observe these extra dimensions in our experiments.

On the other hand, the compactified dimensions approach suggests that the extra dimensions are extremely small and curled up, making them invisible to our current technology. This approach is supported by mathematical consistency and has the advantage of preserving the observed four dimensions of space and time. However, it also faces challenges in explaining the specific shape and size of these extra dimensions.

In terms of making contact with physics, it is difficult to determine which approach is more accurate as both have their own strengths and challenges. Perhaps, a combination of both approaches could provide a more comprehensive understanding of the extra dimensions and their role in our physical world.

As for the question of having 1-2 large dimensions and a 4-folded Yau-Calabi space, this is a possibility that has been explored in some theoretical models. However, it is important to note that these are still theoretical concepts and have not been confirmed by empirical evidence.

In conclusion, the concept of extra dimensions and dimensional reduction is a complex and ongoing topic of research in string theory. While both approaches have their own merits, it is important for scientists to continue exploring and testing these theories in order to gain a deeper understanding of the fundamental nature of our universe.