The fundamental background energy that permeates all of the space in the universe is known as vacuum energy. It is the zero-point energy that is related to the quantum vacuum and whose effects are believed to have an impact on the behavior of the universe on cosmological scales and have been empirically detected in a variety of phenomena including spontaneous emission, the Casimir effect, and the Lamb shift.

Georges Lemaître postulated the existence of vacuum energy as the cause of the cosmological constant in 1934 using an unusual perfect-fluid equation of state. The Casimir effect gave researchers an experimental way to confirm the presence of vacuum energy in 1948; nevertheless, Evgeny Lifshitz proposed a different explanation for the Casimir effect in 1955.

The notions of broken symmetry and parity violation were established by Lee and Yang in 1957, for which they were awarded the Nobel prize. The zero-energy universe was an idea put forth by Edward Tryon in 1973. It was suggested that the cosmos might be a vast quantum-mechanical vacuum fluctuation where positive mass energy is balanced by negative gravitational potential energy.

There were numerous attempts in the 1980s to link the fields that produce vacuum energy to particular fields that attempt a grand unification theory attempted to predict, and utilize observations of the universe to support one or another interpretation. The precise makeup of the particles (or fields) responsible for producing vacuum energy at a density consistent with inflation theory is still unknown.

Vacuum energy is mathematically equal to Einstein’s cosmological constant. The modern understanding of the vacuum, based on quantum field theory, holds that vacuum energy naturally arises from the totality of quantum fluctuations—virtual particle-antiparticle pairs that come into existence and then annihilate each other shortly after in space, even though Einstein and others rejected the cosmological constant.

Although quantum field theory predicts a value of 10110 ergs per cubic centimeter, the observed cosmic vacuum energy density is 1010 ergs per cubic centimeter. Even before the existence of the far weaker dark energy was discovered, this 10120-fold difference was recognized. Although a basic solution to this issue has not yet been discovered, probabilistic alternatives have been put up as a result of the string theory and the conceivable presence of many disconnected universes.

Where did the notion of vacuum energy originate? A field in physics can be thought of as if space were filled with interconnected vibrating balls and springs, and the strength of the field is like the displacement of a ball from its resting position. The quantum field theory suggests that all fundamental fields, such as the electromagnetic field, must be quantized at every point in space. The same theory provides that the “vibrations” in such a field, or more precisely changes in its strength, must spread according to the suitable wave equation for the specific field in issue. Each of these ball-spring combinations must be quantized, i.e., the strength of the field must be quantized at each location in space, according to the second quantization of quantum field theory.

Hence, if the field is a simple harmonic oscillator at every point in space, then its quantization creates a quantum harmonic oscillator at every location. The fundamental particles of particle physics are represented by the field’s excitations. Based on the theory, even the vacuum has a remarkably complicated structure, and all quantum field theory calculations must be performed using this vacuum model.

Virtual particles, often referred to as vacuum fluctuations, which are produced and destroyed from the vacuum can also be used to conceptualize vacuum energy. These particles are always produced from nothing as particle-antiparticle pairs, which typically quickly destroy one another and vanish. Feynman diagrams can be used to map how these particles and antiparticles might interact with one another before dissipating. Be aware that this approach to calculating vacuum energy suffers from the same renormalization issues as having a quantum harmonic oscillator at each site due to its mathematical equivalent.

Scientists theorize that the entire amount of vacuum energy in our universe is very minimal, and may even be zero. The total amount of vacuum energy is thought by many theorists to be exactly zero. It is undoubtedly feasible to control vacuum energy. The quantum mechanical vacuum state is distorted by any objects (such as gravitational fields, dielectrics, and electrical conductors) that modify the vacuum energy. It is frequently simpler to compute these variations in vacuum energy than the total vacuum energy itself.

Vacuum energy has a number of implications. The existence of a modest attractive force between two closely spaced metal plates was predicted by Dutch physicists Hendrik B. G. Casimir and Dirk Polder in 1948 as a result of resonances in the vacuum energy between the plates. The Casimir effect has subsequently been widely experimentally confirmed, earning its name. Therefore, it is thought that the vacuum energy is “real” in the same way that more well-known conceptual concepts like electrons, magnetic fields, etc. Alternative theories regarding the Casimir effect, however, have since been put forth.

The vacuum energy has significant effects on physical cosmology as well. According to general relativity, energy and mass are identical, so if vacuum energy is “truly there,” it should have gravitational effects. In essence, it is anticipated that non-zero vacuum energy will contribute to the cosmological constant, which influences the universe’s expansion.

The Zero Point Module (ZPM) is a power source in the science fiction television program Stargate Atlantis that draws vacuum energy from a tiny parallel reality.

The workings of the so-called Quantum torpedo are described in the book Star Trek: Deep Space Nine Technical Manual. In this hypothetical weapon, a multi-dimensional membrane is created in a vacuum using an antimatter reaction that releases more energy during its breakdown than it took to make it. The vacuum gets filled with the energy that is lacking. The energy released in the explosion is typically roughly twice as much as what the original annihilation of antimatter would have produced.

Vacuum energy has also been used in various works of fiction. The Zero Point Module (ZPM) is a power source in the science fiction television program Stargate Atlantis that draws vacuum energy from a tiny parallel reality.

Meanwhile, the workings of the so-called Quantum torpedo are described in the book Star Trek: Deep Space Nine Technical Manual. In this hypothetical weapon, a multi-dimensional membrane is created in a vacuum using an antimatter reaction that releases more energy during its breakdown than it took to make it. The vacuum gets filled with the energy that is lacking. The energy released in the explosion is typically roughly twice as much as what the original annihilation of antimatter would have produced.