Linked Questions
15 questions linked to/from What is polarisation, spin, helicity, chirality and parity?
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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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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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A thought experiment about neutrinos
I don't understand all the details of Dirac mass, Majorana mass, and many other "deep" notions.
I have in mind a very simple thought experiment.
Because of neutrino oscillations we know ...
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Is photon spin and polarization the same thing?
I have posted here regarding this before. I always get conflicting information when I research about this stuff.
Some people say that a photon spins in or against it’s direction of motion…meaning if ...
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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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What is the analog to the electric field for those particles (different to photon) that have a polarisation?
Photon has a polarisation. The polarisation defines how the two components of the electric field evolves with times in the transverse plane.
Those particles, different to photon, that have a spin $s$ ...
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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 ...
user104372
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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). ...
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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 ...
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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?
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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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How do massless particles have the same chirality and helicity when they are different properties?
I read this article about chirality and helicity. At some point it says
For massless particles, chirality is the same as helicity.
But as far as I know, helicity takes form in numbers, $(-1/2, +1/2)...
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Charged fermions have both chiralities, with the same mass. Shouldn’t neutrinos, also massive, have both chiralities, though with different masses?
Thanks to answers a previous question, I have realised the difference between helicity, a non-Lorentz-invariant quantity, and the Lorentz invariant chirality.
Let me summarise what I understand, ...
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The helicity and spin conservation in the $e^+e^-\rightarrow \mu^+ \mu^-$ process
A related post was What is polarisation, spin, helicity, chirality and parity?
In $m_\mu<<E$ region, $m_\mu$ could be treated as massless particles and the conservation of helicity indicated the ...
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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 ...
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