Dr. Jayant Narlikar, a renowned Indian astrophysicist and cosmologist, proposed the 'Cosmic Ancestry Hypothesis', which posits that life on Earth arose from interstellar dust and gas.

Dr. Subrahmanyan Chandrasekhar's 'Stellar Evolution Theory' explains that when a star exhausts its nuclear fuel, it collapses under its own gravity, resulting in the formation of a neutron star.

Dr. M.N. Saha's 'Thermal Ionization Equation' is crucial in understanding stellar nucleosynthesis, the process by which elements are formed within stars.

Dr. Hannes Alfvén, a Swedish physicist, proposed the 'Plasma Universe Hypothesis', which suggests that the universe is predominantly composed of plasma, a state of matter consisting of ionized particles.

Dr. C.V. Raman's 'Raman Scattering Theory' explains that when light interacts with molecules, its wavelength changes, giving rise to the phenomenon known as Raman scattering.

Dr. Vikram Sarabhai's major contributions were in the field of satellite communication, where he played a pivotal role in establishing India's satellite communication system.

Dr. Fred Hoyle, a British astronomer, proposed the 'Steady State Theory', which suggests that the universe is continuously expanding and creating new matter to maintain a constant density.

Dr. Homi J. Bhabha's 'Causal Set Theory' is a significant contribution to the field of quantum gravity, which aims to unify the principles of quantum mechanics and general relativity.

Dr. Jayant Narlikar proposed the 'Zero-Energy Universe Hypothesis', which suggests that the total energy of the universe is zero, implying a balance between positive and negative energy.

Dr. Subrahmanyan Chandrasekhar's 'Chandrasekhar Limit' states that a white dwarf star cannot exceed 1.4 solar masses before collapsing under its own gravity and becoming a neutron star.

Dr. Subrahmanyan Chandrasekhar's 'Black Hole Theory' proposed the existence of regions in spacetime called black holes, where gravity is so intense that nothing, including light, can escape.

Dr. M.N. Saha's 'Saha Equation' is crucial in understanding the ionization and excitation processes occurring in stellar atmospheres.

Dr. Hannes Alfvén, a Swedish physicist, proposed the 'Plasma Universe Hypothesis', which suggests that the universe is predominantly composed of plasma, a state of matter consisting of ionized particles.

Dr. C.V. Raman's 'Raman Scattering Theory' explains that when light interacts with molecules, its wavelength changes, giving rise to the phenomenon known as Raman scattering.

Dr. Vikram Sarabhai's major contributions were in the field of satellite communication, where he played a pivotal role in establishing India's satellite communication system.