Linked Questions

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0answers
52 views

Left-handed and right-handed helicity, can you explained well the phenomenon of chirality simply? [duplicate]

Chirality, helicity as a projection of its spin vector .. that becomes a kind of 'virtual spin'? I often confuse them: but the particles 'spin' on the right or left, or is the projection of .. what? ...
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4answers
13k views

What's the difference between helicity and chirality?

When a particle spins in the same direction as its momentum, it has right helicity, and left helicity otherwise. Neutrinos, however, have some kind of inherent helicity called chirality. But they can ...
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2answers
2k views

The electron and neutrino spin

Can you please clarify some basic notions about spin? Can you please explain what is intended when they say that the spin of a neutrino is left-handed and equal to -1/2? Does it mean its angular ...
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2answers
666 views

Transverse polarizations of a massless spin 1 particle

Physical polarization vectors are transverse, $p\cdot{\epsilon}=0$, where $p$ is the momentum of a photon and $\epsilon$ is a polarization vector. Physical polarization vectors are unchanged under a ...
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1answer
411 views

What are the differences between chiral states and helical states in condensed matter physics?

As we know in particle physics, chirality corresponds to eigenvalues of the fifth gamma matrix, and helicity corresponds to the value of the projection of spin onto momentum. So in condensed matter ...
1
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1answer
341 views

Why is helicity important in quantum field theory?

What makes helicity an important quantity in quantum field theory? I know that one can classify particles by mass and spin. For particles without mass one uses helicity (correct me if this is wrong). ...
2
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2answers
130 views

Difference between left- and right-handed, helicity and chirality

What is the difference? I know there is the (almost) same question What's the difference between helicity and chirality? but when a particle is given as left-handed. Is it helicity or chirality?
1
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1answer
141 views

Weak interaction, parity violation, and the observer-dependence of helicity

It is said that the Weak Interaction only couples to left-handed particles which a negative spin (left-handed). However some sources say that spin or helicity is dependent on the observer's position ...
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0answers
35 views

What's the relation between the Lorenztz group and spin of particles?

I know that particles are defined in terms of irreducible representations of the Poincaré group, and that the state of a massive particle is defined by its mass and spin, which are the eigenvalues of ...