Cosmological Models with Scalar and Spinor Fields

Contemporary cosmological research has increasingly explored the role of scalar and spinor fields as dynamic constituents of the Universe’s evolution. Scalar fields, characterised by a single value at each point in space–time, serve as paradigms for inflationary dynamics and models of dark energy. Their potentials govern acceleration phases, from early‐time inflation to late‐time cosmic acceleration. Spinor fields, on the other hand, introduce fermionic degrees of freedom into gravity theories. They appear in scenarios where nonlinear self‐interactions of spinor bilinears can mimic dark energy or drive anisotropic expansion in Bianchi cosmologies. Coupling of spinor matter to the gravitational field may yield nontrivial off‐diagonal components in the energy–momentum tensor, imposing geometric constraints that influence the scale factor’s evolution. Hybrid constructions that combine scalar inflatons with spinor condensates offer avenues to reconcile high‐energy predictions with observed perturbation spectra. Across these approaches, the interplay between field equations and cosmological observables such as the Hubble parameter, the growth of density perturbations and the cosmic microwave background anisotropies elucidates the viability of novel mechanisms for inflation, dark matter and dark energy. This interdisciplinary framework links quantum‐field formalisms to astrophysical data, underscoring the global significance of models in which fundamental fields shape cosmic history.

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Cosmological Models with Scalar and Spinor Fields publication trend

The graph below shows the total number of articles in cosmological models with scalar and spinor fields across all publications each year (not limited to Nature Index journals).

Technical terms

Scalar field: A field described by a single-valued function on space–time, often used to model inflaton or dark‐energy components.

Spinor field: A fermionic field transforming under spinorial representations of the Lorentz group, capable of self‐interaction and coupling to gravity.

Grassmann variable: An anticommuting number used to represent fermionic degrees of freedom in field theory.

Equation of state parameter: The ratio of pressure to energy density (w) that characterises the dynamical properties of a cosmological fluid.

FLRW metric: A homogeneous and isotropic space–time geometry defined by the Friedmann–Lemaître–Robertson–Walker line element.

Coleman–De Lucia instanton: A quantum tunnelling solution in Euclidean space–time that mediates vacuum decay or the onset of inflation.

References

1. Fermionic wave functions and Grassmann fields as possible sources of dark energy. European Physical Journal C (2022).
2. Tachyonic open inflationary universes. Physics Letters B (2007).
3. Spinor Field in FLRW Cosmology. Universe (2023).