arXiv:2511.02878v1 Announce Type: new
Abstract: Real, time-dependent scalar fields can form oscillating, self-gravitating configurations-oscillatonsthat are viable candidates for scalar-field dark matter (SFDM). We revisit oscillatons with an exponential self-interaction and develop a full Fourier (Jacobi{Anger) treatment that resums the time dependence of both the metric and the potential, thereby unifying quadratic, quartic, and higher-order interactions within a single framework. After fixing the small-amplitude normalization V0 = m2 {Phi}=({lambda}2k0), we derive a closed, dimensionless boundary-value problem for the radial profiles and solve it numerically via Bessel-series truncation with controlled convergence. We compute time-resolved and time-averaged observables energy density, radial energy flux, radial/tangential pressures, and total mass and map their dependence on the coupling {lambda} and central amplitude. The geometry exhibits only even harmonics of the fundamental frequency, while composite observables inherit a DC part plus even harmonics; the radial flux oscillates predominantly at 2!. Apparent negative instantaneous pressures arise from coherent oscillations and are assessed consistently through classical energy-condition diagnostics (WEC/NEC/SEC). Our formulation provides a reproducible and extensible baseline for stability analyses and observational constraints on SFDM oscillatons
Future Roadmap:
Challenges:
- Further refinement of stability analyses and observational constraints on SFDM oscillatons
- Improving numerical methods for solving the closed, dimensionless boundary-value problem
- Addressing apparent negative instantaneous pressures and their implications
Opportunities:
- Exploring the potential of oscillatons as viable candidates for scalar-field dark matter
- Utilizing the unified framework for quadratic, quartic, and higher-order interactions to study various aspects of oscillatons
- Investigating the time-resolved and time-averaged observables to gain insight into the behavior of oscillatons
Conclusion:
The study of oscillatons with an exponential self-interaction provides a solid foundation for further research into scalar-field dark matter. By developing a full Fourier treatment and deriving a closed boundary-value problem, researchers can continue to explore the properties and potential applications of oscillatons. Addressing challenges such as stability analyses and negative pressures will unlock new opportunities for understanding the role of oscillatons in the broader context of dark matter and cosmology.