Quick Calculation 14.4b | A First Course in String Theory

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Massive level in the open superstring

Consider the first and second excited levels of the open superstring ( and ). List the states in NS sector and the states in the R sector. Confirm that you get the same number of states.

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When , by Equation (14.54), the possible states are

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For , the number of states is 8.

For , the number of states is .

For , the number of states is .

For , the number of states is .

For , the number of states is 8.

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However, since each of and has 8 possible values, there is an additional multiple of 8.

The total number of states is .

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You can check this answer against Equation (14.67):

— Me@2018.02.20 10:57 AM

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2018.02.20 Tuesday (c) All rights reserved by ACHK