Larmor precession of an electron in a magnetic field?

In summary, Larmor precession is a phenomenon where the spin of an electron in a magnetic field rotates around the direction of the field. This is due to the interaction between the electron's magnetic dipole moment and the external magnetic field. The gyromagnetic ratio, which relates the electron's magnetic dipole moment to its spin angular momentum, determines the frequency of the precession, known as the Larmor frequency. Factors such as the strength of the magnetic field, the electron's mass and charge, and interactions with other particles or fields can affect this frequency. Larmor precession is observed in everyday devices such as NMR and MRI machines, as well as compasses and other navigation tools. In quantum mechanics, it is a fundamental phenomenon
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how does one describe the Larmor precession of a spin 1/2 particle in a magnetic field in terms of quantum field theory?
In QFT where the electromagnetic field is mediated by virtual photons, is it possible to describe the larmor precession of an electron as a series of emission and absorption of virtual photons? how does the spin angular momentum "evolve" over a series of events? This feels like a challenging question.. I really appreciate a helpful answer thank you.
 
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An external classical field in QED is described as a coherent state. In perturbative terms it's given by the corresponding resummation of the "soft-photon ladders". For details see Weinberg, Quantum Theory of Fields, vol. 1.
 
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FAQ: Larmor precession of an electron in a magnetic field?

What is Larmor precession?

Larmor precession is the phenomenon where a charged particle, such as an electron, rotates around the direction of an external magnetic field at a specific frequency.

How is Larmor precession related to the spin of an electron?

Larmor precession is directly related to the spin of an electron. The spin of an electron creates a magnetic moment, which interacts with an external magnetic field, causing the electron to precess.

What is the equation for the Larmor precession frequency?

The equation for the Larmor precession frequency is f = γB, where γ is the gyromagnetic ratio and B is the strength of the external magnetic field.

How is Larmor precession used in scientific research?

Larmor precession is used in a variety of scientific fields such as nuclear magnetic resonance (NMR), electron spin resonance (ESR), and magnetic resonance imaging (MRI). It is also used in particle accelerators to control the trajectory of charged particles.

Can Larmor precession be affected by external factors?

Yes, Larmor precession can be affected by external factors such as temperature, pressure, and other magnetic fields. These factors can alter the precession frequency and direction of the charged particle.

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