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Kirti Verma,
Parth Khare,
- Associate Professor, Department of Engineering Mathematics Gyan Ganga Institute of Technology and Sciences Jabalpur, Madhya Pradesh, India
- Assistant Professor, Department of Engineering Mathematics Gyan Ganga Institute of Technology and Sciences Jabalpur, Madhya Pradesh, India
Abstract
Cosmology is the scientific study of the origin, evolution, composition, structure, and ultimate fate of the Universe. Modern cosmology integrates theoretical physics, astronomy, particle physics, and observations to develop quantitative models of cosmic evolution from the earliest observable epochs to the present large-scale Universe. The prevailing cosmological framework, known as the Lambda Cold Dark Matter (ΛCDM) model, provides a successful description of a wide range of observations, including the cosmic microwave background (CMB), cosmic expansion, galaxy formation, gravitational lensing, supernovae, and the distribution of large-scale cosmic structures. According to the hot Big Bang model, the observable Universe evolved from an extremely hot and dense early state and has expanded and cooled over approximately 13.8 billion years. Cosmic inflation provides a theoretical mechanism that can account for the large-scale homogeneity, isotropy, near-flatness, and primordial density fluctuations observed in the Universe. Observational evidence indicates that ordinary baryonic matter constitutes only a small fraction of the cosmic energy budget, whereas dark matter and dark energy dominate the present-day Universe. Despite the remarkable success of ΛCDM, several fundamental questions remain unresolved, including the microscopic nature of dark matter, the physical origin of dark energy, the mechanism responsible for inflation, and the persistent discrepancy between some measurements of the Hubble constant. Large-scale observational programs, particularly the Dark Energy Spectroscopic Instrument (DESI), are providing increasingly precise measurements of baryon acoustic oscillations, galaxy clustering, and cosmic expansion. This review summarizes the foundations of modern cosmology, the Big Bang and inflationary paradigms, observational evidence from the CMB and large-scale structure, the ΛCDM framework, and major current challenges. It also discusses future observational directions that may provide tests of the standard cosmological model and reveal new physics.
Keywords: Cosmology; Big Bang; ΛCDM model; Cosmic Microwave Background; Dark
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International Journal of Universe
| Volume | 02 | |
| 02 | ||
| Received | 24/09/2026 | |
| Accepted | 25/09/2026 | |
| Published | 10/10/2026 | |
| Publication Time | 16 Days |