Subrahmanyan Chandrasekhar

Definition

Subrahmanyan Chandrasekhar was a renowned Indian-American astrophysicist known for his work on the structure and evolution of stars, particularly his formulation of the Chandrasekhar limit. This critical mass limit describes the maximum mass of a stable white dwarf star, beyond which it cannot support itself against gravitational collapse, leading to phenomena like supernovae and neutron stars. His research has had profound implications in understanding stellar evolution and the lifecycle of stars.

5 Must Know Facts For Your Next Test

1. Chandrasekhar was awarded the Nobel Prize in Physics in 1983 for his theoretical studies on the physical processes important to the structure and evolution of stars.
2. The Chandrasekhar limit is approximately 1.4 solar masses; any white dwarf exceeding this mass will collapse into either a neutron star or black hole.
3. His work demonstrated how stellar evolution leads to different types of celestial objects, including white dwarfs, neutron stars, and black holes.
4. Chandrasekhar's theories revolutionized astrophysics by providing a deeper understanding of how stars end their life cycles and contribute to cosmic phenomena.
5. He also contributed significantly to other fields in astrophysics, including radiation transport and the study of accretion disks around compact objects.

Review Questions

• How did Subrahmanyan Chandrasekhar's work contribute to our understanding of white dwarfs and their limitations?
  • Chandrasekhar's research established the concept of the Chandrasekhar limit, which indicates that a white dwarf can only maintain its structure up to about 1.4 solar masses. If it exceeds this limit, gravitational forces will overpower electron degeneracy pressure, leading to collapse into a neutron star or black hole. This groundbreaking finding was crucial in explaining why certain stars end their lives as white dwarfs while others become more exotic objects.
• Discuss the implications of the Chandrasekhar limit on stellar evolution and supernova occurrences.
  • The Chandrasekhar limit plays a critical role in stellar evolution by dictating the fate of white dwarfs. Stars that exceed this mass threshold can no longer support themselves and may undergo catastrophic collapse, resulting in supernova explosions. This process enriches the interstellar medium with heavy elements created during the star's lifetime and during the explosion, impacting future star formation and galactic chemical evolution.
• Evaluate how Subrahmanyan Chandrasekhar's theories have influenced modern astrophysics and our understanding of cosmic structures.
  • Chandrasekhar's theories have profoundly shaped modern astrophysics by providing insights into stellar structures and life cycles. His work on the Chandrasekhar limit has been fundamental in explaining not just white dwarfs but also leading to an understanding of neutron stars and black holes. These contributions have opened pathways for further research in cosmology and helped in exploring phenomena like gamma-ray bursts and gravitational waves, underscoring his lasting impact on how we comprehend cosmic structures and their evolution over time.

Related terms

White Dwarf: A white dwarf is a small, dense star that is the remnant core of a low or medium mass star, formed after it has exhausted its nuclear fuel.

Supernova:

A supernova is a powerful and luminous explosion that occurs at the end of a star's life cycle, often resulting from the collapse of a massive star or the thermonuclear explosion of a white dwarf.

Neutron Star: A neutron star is an incredibly dense stellar remnant formed from the collapse of a massive star after a supernova, consisting primarily of neutrons packed closely together.