A repulsive force that exists in quantum mechanics between identical fermions due to the Pauli exclusion principle.

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Exchange interaction and time evolution of reduced density matrix

Given a system of two spin 1/2 coupled via exchange interaction $$ H = \Delta\epsilon S_2^z + J(t)\mathbf{S}_1\mathbf{S}_2$$ which is allowed to be time dependent, but different from zero only for ...
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How does magnetic field leverage exchange interaction?

A 1 Tesla magnetic field corresponds to the energy of less than a millielectronvolt. However, fields of that order seem to saturate the magnetization of many solids, be they ferromagnets or ...
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Outside of string theory, can exchange particles be understood as being one-dimensional?

I'm pretty new to quantum, without any formal education therein, so forgive my general layman ignorance when I ask how it is that point-like exchange particles can be modeled in Feynman diagrams as ...
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What are the possible reasons of deviation from Curie Weiss behavior well above Tc?

I think existence of other weak interactions which have higher transition temperature than the observed prominent interaction(ferro/antiferro) can perhaps lead to such result but I am confused when ...
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spin conservation in exchange polarization process

Exchange polarization is the process by which spin is transferred between an electron beam and a system of polarized atoms (with a single valence spin). The process occurs as a result of the Pauli ...
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Exchange operator in terms of rotation operator

I have studied about exchange operators and rotation operators and I know that an exchange between 2 particles in a combined state is the same as rotating each particle 180 degrees (according to ...
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114 views

Is there a point interaction model of the electron?

Is there a point interaction model of the electron? Is there a point interaction model of the electron? I imagine something like $\propto(\bar \psi\psi)^2$ (edited). Is such a thing in use? Since I ...
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138 views

Does spin alone have any effect on the physical interactions of particles?

In Hartree-Fock theory the time-independent electronic energy of a single (restricted) determinant electronic wavefunction consists of one electron terms, $h_{ii}$, Coulomb interaction energies, ...
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Simple description of exchange interaction?

What is a simple bare-bones description of exchange interaction between two electrons? For instance, it seems to me that the only necessary ingredients are the Coulomb interaction and the requirement ...
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electron hole exchange

If exchange is an interaction between indistinguishable particles, how can there be an exchange interaction between electrons and holes? I see mention of e-h exchange often in the literature.
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Are all electrons identical?

Why should two sub-atomic (or elementary particle) - say electrons need to have identical static properties - identical mass, identical charge? Why can't they differ between each other by a very ...
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Example of a wavefunction that cannot be represented by a single Slater determinant

I know that in general, interacting fermions cannot necessarily be described by a single Slater determinant. Can anyone provide a simple example of a state that has no such representation?
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How would Kohn-Sham orbitals differ from 'true' elecron wavefunctions?

How would the non-interacting electron orbitals from a perfect DFT solution for a given potential shape differ from the 'true' electron wavefunctions? Or can you only really talk about the total ...
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existing bounds on maximum density achieved by a Bose condensate

As we know, fermions are subject to exchange interactions that limit the densities they can achieve. However bosons (simple or composite) are not constrained by this, which implies physical phenomena ...