Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

In quantum mechanics, uncertainty principle states that we can only measure the quantity of spin in one axis but not others.

Then what about in superstring theory? As quantum mechanics is basically three-dimensional world, this does make sense, but superstring theory adopts more than three-dimensional space...

share|improve this question

1 Answer 1

up vote 0 down vote accepted

The properties of spin in higher dimensions mean that you can measure d/2 spin directions simultaneously, corresponding to a set of maximally commuting rotation planes. For example, in 4d, you can measure the spin in the x-y rotation plane and the z-w rotation plane, simultaneously, but not the spin in the x-y and x-w planes.

The angular momentum of objects in string theory obeys the same commutation relations as in any other quantum theory, so in string theory, the spins are restricted as above--- you can measure as many of these simultaneously as there are independent rotation planes.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.