Theoretical physics -- where does spin 1/2 come in

Thread starter Pearly
Start date Jun 13, 2017
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Physics Spin Spin 1/2 Theoretical Theoretical physics

In summary, spin 1/2 is a fundamental property of subatomic particles that measures their intrinsic angular momentum and is quantized to specific values. It is related to the spin-statistics theorem, which states that particles with half-integer spin must obey the Pauli exclusion principle. Spin 1/2 is crucial in quantum mechanics as it affects particle behavior and interactions, such as through the exchange of virtual particles. Spin 1/2 particles can only have a spin of +1/2 or -1/2 and cannot have other values due to the quantization of spin.

Jun 13, 2017

Pearly

How did they figure out that particles have spin.where does spin 1/2 come in...how was that detected?

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Jun 13, 2017

jtbell

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The two big names here are Uhlenbeck and Goudsmit. Put "uhlenbeck goudsmit electron spin" into Google and you'll get lots of reading material.

Related to Theoretical physics -- where does spin 1/2 come in

1. What is spin 1/2 in theoretical physics?

Spin 1/2 refers to a fundamental property of subatomic particles, such as electrons and protons. It is a measure of the intrinsic angular momentum of a particle and is quantized, meaning it can only have specific values. In quantum mechanics, spin 1/2 is represented by a two-dimensional vector space, with the spin up and spin down states forming a basis for this space.

2. How is spin 1/2 related to the spin-statistics theorem?

The spin-statistics theorem states that particles with half-integer spin, such as spin 1/2 particles, must obey the Pauli exclusion principle, which states that no two identical particles can occupy the same quantum state simultaneously. This theorem has been shown to hold true for all known particles in the universe.

3. Why is spin 1/2 important in quantum mechanics?

Spin 1/2 plays a crucial role in quantum mechanics as it is a fundamental property of particles that affects their behavior and interactions. For example, the spin of electrons is responsible for the magnetic properties of materials and is essential for understanding the structure and behavior of atoms.

4. How does spin 1/2 affect particle interactions?

Spin 1/2 particles, such as electrons, can interact with other particles through the exchange of virtual particles, known as gauge bosons. The spin of these particles determines the strength and type of interaction, with particles of opposite spin exhibiting attractive interactions and particles of the same spin exhibiting repulsive interactions.

5. Can spin 1/2 particles have other values of spin?

No, spin 1/2 particles are always found to have a spin of either +1/2 or -1/2, with no other possible values. This is due to the quantization of spin, meaning it can only exist in discrete, specific values. Other particles, such as bosons, can have different values of spin, such as 0 or 1, but never 1/2.