Superstrings

Question 1

What is the normal ordering constant in the R sector?

Answer 1

It is zero because the infinite sums are the same for the alpha and the d terms in M^2 and the d operators anti-commute.

Question 2

in a spacetime supersymmetric theory the number of bosonic dof in the spacetime low energy field
theory equals the number of

Answer 2

fermionic dof

Question 3

Fermions in superstring theory have a lower index that is (-,+). What does this determine?

Answer 3

It determines the fermion number. To solve the tachyon and numbering problems the NS sector is truncated to the NS+ sector (no tachyon) and the R sector is truncated to the R- sector

Question 4

Name the open superstring sectors and the closed superstring states

Answer 4

Open: R-, NS+
Closed: (NS+,NS+), (NS+, R+), (R-, NS+), (R-,R+)

Question 5

In what closed string sector does the Rarita Schwinger fields (for supergravity) exist?

Answer 5

in (NS+, R+)

Question 6

String theory IIB and IIA are produced from the (R-, NS+) [or (R-, R+-)] closed superstring sector. What is their difference?

Answer 6

IIB has two fields with the same chirality. (R-,NS+), (NS+, R-)

Question 7

Only one of IIA and IIB is chiral. Which one?

Answer 7

IIB is chiral