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arXiv · 0903.0426

A "toy" model in QFT with no lower bound to the energy

Dan Solomon
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Abstract

In quantum field theory, it is generally assumed that there is a lower bound to the energy, which is normally assumed to the the vacuum state. While this may be a reasonable assumption for a free field it is not necessarily the case for interacting fields. In this paper I will examine a "toy" model of a neutral scalar field interacting with a charged scalar field and show that there is no lower bound to the energy in this case.

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Dan Solomon. 2009-03-14. A "toy" model in QFT with no lower bound to the energy. https://arxiv.org/abs/0903.0426

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