"Properly speaking, in 1+1 dim. no such thing as spin, but"

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In summary, the spin-statistics theorem states that in two-dimensional local quantum field theory, an anticommuting field must have half-integral Lorentz quantum numbers, and this is related to the behavior of fields under the two-dimensional Lorentz group.
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Could you please put the conclusion ("The spin-statistics theorem says that in local quantum field theory in two dimensions an anticommuting field must have half-integral Lorentz quantum numbers.") of the following quote in simpler terms if possible,

"Properly speaking, in 1+1 dimensions there is no such thing as spin, but there is a two-dimensional Lorentz group (or local Lorentz group, in the case of a generally covariant theory), and it makes sense to ask how a two-dimensional field transforms under this group. The spin-statistics theorem says that in local quantum field theory in two dimensions an anticommuting field must have half-integral Lorentz quantum numbers."

Quote from Google book search "is there a spin statistics theorem in 1 + 1 spacetime dimensions"

Bottom of page 187, https://books.google.com/books?id=_18hAwAAQBAJ&pg=PA187&dq=string theory: volume 1, introduction&hl=en&sa=X&ei=dr-yVOTQO8rasAStkIGQBg&ved=0CCwQ6AEwAw#v=onepage&q=string theory: volume 1, introduction&f=false

Also does this answer my early question about what the 2 component spinor solutions of the Dirac equation in 1+1 dimensions represent?

Thanks for any help!
 
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In simpler terms, the spin-statistics theorem states that in a two-dimensional world, there is no concept of spin, but there is a two-dimensional Lorentz group that describes how fields behave under transformations. In local quantum field theory, an anticommuting field in two dimensions must have half-integral Lorentz quantum numbers. This means that the field behaves differently under the Lorentz group compared to fields in higher dimensions. And yes, the 2 component spinor solutions of the Dirac equation in 1+1 dimensions represent the behavior of fields under the two-dimensional Lorentz group.
 

1. What does it mean when you say "in 1+1 dim. no such thing as spin?"

When we say "in 1+1 dim. no such thing as spin," we are referring to the dimensionality of space. In a 1+1 dimensional space, there are only two dimensions - one for space and one for time. In this simplified space, there is no room for the concept of spin, which is a characteristic of particles in three-dimensional space.

2. Why is spin not present in 1+1 dimensional space?

In three-dimensional space, particles have the ability to rotate around their own axis, which is known as spin. This rotation is not possible in 1+1 dimensional space because there is only one spatial dimension. Therefore, the concept of spin does not apply in this simplified space.

3. Can spin still be observed in 1+1 dimensional space?

No, spin cannot be observed in 1+1 dimensional space because it is not a property of particles in this simplified space. Spin is only observed in three-dimensional space, where particles have the ability to rotate around their axis.

4. How does the absence of spin affect particle behavior in 1+1 dimensional space?

In 1+1 dimensional space, particles do not have the ability to rotate around their axis, so their behavior is different from particles in three-dimensional space. This simplified space does not have the same physical laws and properties as three-dimensional space, so particles in 1+1 dimensional space behave differently.

5. Are there any real-world applications of studying spin in 1+1 dimensional space?

While 1+1 dimensional space is a simplified concept and does not exist in our physical world, studying the absence of spin in this space can help us better understand the behavior of particles in three-dimensional space. This understanding can lead to advancements in various fields such as quantum mechanics and particle physics.

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