Black Holes and Curved Spacetime

These flashcards cover key concepts related to black holes and curved spacetime, including formation, principles of general relativity, and significant discoveries in black hole physics.

What are black holes formed from?

Black holes can form from the core collapse of stars greater than 20 solar masses in a hypernova.

What happens to a star's core when it collapses into a black hole?

The core collapses to a singularity with zero volume and infinite density, and only its gravity remains.

How does gravity affect light around a black hole?

Gravity is so strong near a black hole that not even light can escape.

What principle connects gravity and acceleration according to Einstein?

The Equivalence Principle states that you cannot distinguish between effects of gravity and acceleration in a closed reference frame.

What is spacetime?

Spacetime is the combination of three dimensions of space plus one dimension of time, which can be curved by mass.

What phenomenon occurs to time in curved spacetime?

Time flows slower in curved spacetime compared to flat spacetime, a phenomenon known as time dilation.

What is the significance of the Schwarzschild radius?

The Schwarzschild radius (rs) is the critical distance from a singularity where nothing can escape, creating the event horizon of a black hole.

What did Karl Schwarzschild achieve in 1915 related to black holes?

Karl Schwarzschild solved Einstein's equations for extreme gravity and discovered the critical distance indicating where gravity is too strong to escape.

What is spaghettification?

Spaghettification is the process where tidal forces near a black hole stretch and shred objects into thin strands.

What did Eddington's experiment demonstrate?

Eddington's experiment confirmed general relativity by showing light from stars appeared bent during a solar eclipse.

What do we understand by gravitational lensing?

Gravitational lensing occurs when mass curves spacetime, causing light from distant objects to follow distorted paths around that mass.

What is gravitational redshift?

Gravitational redshift is when light loses energy while escaping a gravitational well, resulting in an increase in wavelength.

What role does mass density play in spacetime?

Mass density determines the degree to which spacetime is warped; concentrated mass causes greater curvature.

How do black holes interfere with the paths of light?

Black holes cause light to curve around their mass, bending its path due to the curvature of spacetime.

What did LIGO detect related to black holes?

LIGO detected gravitational waves generated by the merger of two black holes, marking a significant event in astrophysics.