- #1
nomadreid
Gold Member
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Given my limited background in Physics, I am restricted to the popular literature on M-theory. After going through this literature (including articles from the very helpful "annotated list of useful literature for String Theory" posted in this rubric of the Forum), I am still puzzled by the following. M-Theory has both open and closed strings, whereby the open strings are attached to D-branes, either on one or two ends. Photons are open strings, gravitons are closed strings. However, for quarks and leptons, I am still confused. In some places they are referred to as open, and some as closed. So:
(a) can they change, being sometimes open, sometimes closed? If so, what does this depend on? If not, which are they?
(b) Are they just one or the other according to which string theory is being used by the particular application of M-theory?
Sorry if the question appears naive, but there is a quantum jump in mathematics requirements between the popular literature and the literature with the deeper results; for those persons in the middle, there is a dearth.
(a) can they change, being sometimes open, sometimes closed? If so, what does this depend on? If not, which are they?
(b) Are they just one or the other according to which string theory is being used by the particular application of M-theory?
Sorry if the question appears naive, but there is a quantum jump in mathematics requirements between the popular literature and the literature with the deeper results; for those persons in the middle, there is a dearth.