negative energy state

physics

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July 1, 2026

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In physics, the concept of a negative energy state, while seemingly counterintuitive, arises in quantum mechanics. One manifestation is the Casimir effect, where the quantum fluctuations in empty space can create a force between closely spaced objects. This effect demonstrates that "empty" space isn't truly empty but contains a "zero-point energy".123

Another theoretical aspect of negative energy states comes from Paul Dirac's extension of quantum mechanics to be compatible with special relativity. This work suggested the possibility of electrons existing with negative energy, though these states are thought to be filled and thus imperceptible. The creation of particle-antiparticle pairs, like electrons and positrons, is linked to these concepts.3

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principles of physical science
Rise of quantum mechanics
…m might exist with any negative energy between −mc² and −∞. Between −mc² and +mc², which is in relativistic theory the energy of an electron at rest, no state is possible. It became clear that other predictions of the theory would not agree with experiment if the negative-energy states were…
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…m might exist with any negative energy between −mc² and −∞. Between −mc² and +mc², which is in relativistic theory the energy of an electron at rest, no state is possible. It became clear that other predictions of the theory would not agree with experiment if the negative-energy states were…
Read More