The document introduces black holes by discussing their origins from proposals in the 18th century and definitions put forth by Einstein. It describes black holes as regions of space where gravity is so strong that not even light can escape, and that are created when large stars collapse at the end of their life cycles. The document outlines three main types of black holes and describes the key parts of black holes, including their event horizons, singularities, accretion disks, and ergospheres. Hawking radiation, in which black holes are predicted to emit and evaporate over time via quantum effects, is also summarized.
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2. INDEX
• Introduction to Black Holes
• What are Black Holes
• How are Black Holes created
• Types of Black Holes
• Parts of Black Holes
3. 1.INTRODUCTION
• The first time the idea was proposed in
1790 by laplace and john michell
• They called it invisible star
• Basic idea through newton`s first law
• Einstein`s prediction in 1915
• In 1967 it was named black hole
4. 2.WHAT ARE BLACK HOLES?
• A black hole is a great amount of matter
packed in a very small area .
• It is a place in space which have such
gravitational field , that nothing , not even
light can escape
• we can`t observe it directly
• It is observed by the effects on nearby
matter from it
• It radiate all types of radiations
5. 3.HOW ARE BLACK HOLES
CREATED?
• A common type of black hole is created by
the dying stars
• For most of the stars life is balanced by
gravity and pulling pressure
• When nuclear fuel is ended the star
shrinks and hence black hole is created
• white dwarf
• Supernova
• Zero volume i.e. infinite volume
• Singularity
6. 4.TYPES OF BLACK HOLES
Mainly there are three types of black holes
• 1: Stellar black holes
• 2: Supermassive black holes
• 3: Miniature black holes
7. WHITE HOLES AND WORMHOLES
• In general relativity , white hole is a
hypothetical region of spacetime which can
not be entered from the outside
• white holes are reversed to black holes
• A wormhole is a theoretical passage
through space time that could create
shortcuts for long journeys across the
universe
• wormhole brings with sudden collapse ,
high radiation and dangerous contact with
exotic matter
8. 5.PARTS OF A BLACK HOLE
The Event Horizon: This is the part of the
black hole where nothing can get out.
It is usually defined as a big sphere that
surrounds the black hole , and which
absorbs any material including light.
9. S
The Singularity: This the part of black
hole in which all the mass of the black
hole has been compressed to a very
small space. As a result, the singularity
has almost infinite density
10. The Accretion Disk
An accretion disk is a structure formed by
diffused material in orbital motion around
a massive central body. Gravitational and
frictional forces increase the temperature
of material that causes emission of
electromagnetic radiation
The Ergosphere
The ergosphere is a region located
outside a rotating black holes`s outer
event horizon.
It is theoretically possible that in this
region mass and energy can be extracted
The Schwarzschild
radius
This is the event horizon`s radius . It is
the radius at which the escape velocity is
equal to the velocity of light.
R=2GM/C^2
11. CURIOUS FACTS ABOUT BLACK
HOLES
• They can explote
• They fire intergalactic death rays
• It is not their mass, it is their size what matters
• Black holes disort space time
• Objects appear to freeze near a black hole
• Black holes eventually evaporate over time
• A 1100 decibel sound would create a black hole with a diameter larger than the
observable universe
12. HAWKING RADIATION
• Hawking radiation is blackbody radiation that is predicted to be released by black
holes , due to quantum effects near the event horizon .
• Hawking radiation reduces the mass and energy of black holes and is therefore also
known as black hole evaporation Because of this, black holes that do not gain
mass through other means are expected to shrink and ultimately vanish.