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arXiv · hep-ph/0603254

Negative Pressures in QED Vacuum in an External Magnetic Field

H. Perez Rojas·E. Rodriguez Querts
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Abstract

Our aim is to study the electron-positron vacuum pressures in presence of a strong magnetic field $B$. To that end, we obtain a general energy-momentum tensor, depending on external parameters, which in the zero temperature and zero density limit leads to vacuum expressions which are approximation-independent. Anisotropic pressures arise, and in the tree approximation of the magnetic field case, the pressure along $B$ is positive, whereas perpendicular to $B$ it is negative. Due to the common axial symmetry, the formal analogy with the Casimir effect is discussed, for which in addition to the usual negative pressure perpendicular to the plates, there is a positive pressure along the plates. The formal correspondence between the Casimir and black body energy-momentum tensors is analyzed. The fermion hot vacuum behavior in a magnetic field is also briefly discussed.

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H. Perez Rojas, E. Rodriguez Querts. 2006-03-30. Negative Pressures in QED Vacuum in an External Magnetic Field. https://doi.org/10.1142/s0217751x06031715

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