Tagged Questions
8
votes
0answers
121 views
Compactifying on a circle and the exchange of R and NS sectors
I've noticed a general phenomenon in compactifying on a circle where if you start with, say, an NS field, then the KK fields with an index along the circle will be in the R sector, and those without ...
1
vote
0answers
54 views
Folded and/or compacted dimensions in M-theory?
I've on many occasions that there are various numbers of 'extra' dimensions above the 4th. However, I've heard that they are 'compacted' or 'folded' tightly and unimaginably small. Now, as I ...
5
votes
2answers
163 views
Why would a particle in an extra dimension appear not as one particle, but a set of particles?
I was reading an article in this months issue of Physics World magazine on the three main theories of extra dimensions and stumbled across something I didn't quite understand when the author began ...
3
votes
2answers
304 views
How can one imagine curled up dimensions?
Actually I'm learning String Theory, and one of its proposals is that there are actually 25+1 dimensions of which only 3+1 are visible to us-- and the remaining are curled up. However, superstring ...
3
votes
2answers
206 views
Measuring extra-dimensions
I have read and heard in a number of places that extra dimension might be as big as $x$ mm. What I'm wondering is the following:
How is length assigned to these extra dimensions?
I mean you can ...
1
vote
2answers
149 views
What is the relation between extra dimensions and unification of theories?
One of the most used methods in unification of theories is the use of higher dimensions. How does it actually work? If these dimensions are extremely small curled up, how does it affect the universe. ...
7
votes
1answer
34 views
Are lens spaces classified via a Weinberg angle?
I am thinking about Kaluza Klein theory in the 3 dimensional lens spaces. These have an isometry group SU(2)xU(1), generically, and in some way interpolate between the extreme cases of manifolds $S^2 ...
1
vote
1answer
120 views
equivalence principle and nontrivial compactifications
it is commonly argued that the equivalence principle implies that everything must fall locally in the same direction, because any local variation of accelerations in a small enough neighbourhood is ...
4
votes
3answers
316 views
Why (in relatively non-technical terms) are Calabi-Yau manifolds favored for compactified dimensions in string theory?
I was hoping for an answer in general terms avoiding things like holonomy, Chern classes, Kahler manifolds, fibre bundles and terms of similar ilk. Simply, what are the compelling reasons for ...
9
votes
1answer
277 views
Measurement of kaluza-klein radion field gradient?
I've been very impressed to learn about kaluza-klein theory and compactification strategies. I would like to read more about this but in the meantime i'm curious about 2 different points. I have the ...
