The Balance between Neutron Pressure and Gravity

The Balance between Neutron Pressure and Gravity

Introduction to Neutron Pressure and Gravity

• In a star, there exists a constant battle between neutron pressure and gravity.

• This battle dictates the life and evolution of a star from its birth till death.

Understanding Neutron Pressure

• Neutron pressure is the force exerted outward by particles in a star’s core.

• When a star has burnt all its nuclear fuel, its core begins to collapse, creating conditions that generate neutrons and result in extreme neutron pressure.

• Neutron pressure is the key to the formation and stability of neutron stars, one possible end state for stars exceeding 8 solar masses.

Understanding Gravity

• Gravity is the contracting force exerted by a star’s mass.

• Acting inward, gravity attempts to reduce the star’s volume by causing the star to collapse in on itself.

• During a star’s life, gravitational forces are balanced by pressure forces associated with the thermal energy of hot gases and radiation.

Balancing Neutron Pressure and Gravity

• When both neutron pressure and gravity are equally powerful, the star reaches a point of equilibrium and becomes a neutron star.

• In this state, gravity’s inward pressure is counterbalanced by the outward neutron pressure.

• Under immense gravity more than 3 solar masses, neutron pressure is not enough to halt gravity’s pull leading to the formation of a black hole.

Importance of the Balance in Stellar Evolution

• The neutron star or the black hole (formed due to imbalance) provide essential clues to the degree of stellar evolution.

• They also demonstrate the intricate equilibrium between forces that dictate the immense variety and dynamism of celestial bodies.

• The balance between neutron pressure and gravity is therefore a crucial concept in understanding stellar evolution.