2. Introduction
This will talk about the summary of the theories of how the universe was created. It will discuss the basic
knowledge about the origins of the universe and how each theory explains how the universe was created.
These are the theories that explain how the universe was created:
3. Fission theory
This theory suggests that early in the Earth's development, the spin
of the Earth was so great that a chunk of Earth flew off. This piece
went into orbit around the Earth, becoming the Moon as we know it.
The fission theory is not supported by fossil evidence here on Earth. If
the Earth had really been spinning fast enough to eject a piece of
itself into space, there would be evidence of this in the geological
record of Earth. Also, this theory doesn't explain the baked surface of
the Moon.
4. Planetary collission theory
In 1898, George Darwin made the suggestion that the Earth and Moon were once a single body.
Darwin's hypothesis was that a molten Moon had been spun from the Earth because of centrifugal
forces, and this became the dominant academic explanation.
Using Newtonian mechanics, he calculated that the Moon had orbited much more closely in the past
and was drifting away from the Earth.
Darwin's calculations could not resolve the mechanics required to trace the Moon backward to the
surface of the Earth.
In 1946, Reginald Aldworth Daly of Harvard University challenged Darwin's explanation, adjusting it to
postulate that the creation of the Moon was caused by an impact rather than centrifugal forces.
A similar approach was taken by Canadian astronomer Alastair G. W. Cameron and American
astronomer William R. Ward, who suggested that the Moon was formed by the tangential impact upon
Earth of a body the size of Mars.
Most of the collisional material sent into orbit would consist of silicates, leaving the coalescing Moon
deficient in iron.
5. Gas Cloud theory
Giant gas clouds in the early universe could have powered the most energetic eruptions
since the big bang.One theory suggests huge gas clouds around at the time collapsed into
middleweight "Seed" black holes. The clouds are so massive that they begin to contract
under their own weight, eventually becoming dense enough to trigger nuclear reactions.
These provide an outward pressure that counteracts the clouds' collapse.
If a giant gas cloud had at least 10 per cent of the sun's proportion of these elements,
they would set off enough reactions to overwhelm gravity's inward pull.
If the cloud contained fewer heavy elements providing outward pressure, gravity would
win out and the cloud would collapse into a seed black hole.
6. Stellar collission theory
A stellar collision is the coming together of two stars caused by stellar dynamics within a star cluster, or by the orbital
decay of a binary star due to stellar mass loss or gravitational radiation, or by other mechanisms not yet well
understood.
Astronomers predict that events of this type occur in the globular clusters of our galaxy about once every 10,000 years.
On 2 September 2008 scientists first observed a stellar merger in Scorpius, though it was not known to be the result of
a stellar merger at the time.
A series of stellar collisions in a dense cluster over a short period of time can lead to an intermediate-mass black hole
via "Runaway stellar collisions".
Any stars in the universe can collide, whether they are 'alive', meaning fusion is still active in the star, or 'dead', with
fusion no longer taking place.
White dwarf stars, neutron stars, black holes, main sequence stars, giant stars, and supergiants are very different in
type, mass, temperature, and radius, and so react differently.
A gravitational wave event that occurred on 25 August 2017, GW170817, was reported on 16 October 2017 to be
associated with the merger of two neutron stars in a distant galaxy, the first such merger to be observed via
gravitational radiation.
7. Big bang theory
The Big Bang Theory is the leading explanation about how the universe began.
At its simplest, it says the universe as we know it started with a small singularity, then inflated over the
next 13.8 billion years to the cosmos that we know today. Because current instruments don't allow
astronomers to peer back at the universe's birth, much of what we understand about the Big Bang Theory
comes from mathematical formulas and models. While the majority of the astronomical community
accepts the theory, there are some theorists who have alternative explanations besides the Big Bang - such
as eternal inflation or an oscillating universe.
The first second, and the birth of light In the first second after the universe began, the surrounding
temperature was about 10 billion degrees Fahrenheit, according to NASA. The cosmos contained a vast
array of fundamental particles such as neutrons, electrons and protons.
"The free electrons would have caused light to scatter the way sunlight scatters from the water droplets in
clouds," NASA stated.
This allowed light to shine through about 380,000 years after the Big Bang.
8. Divine theory
Divine Command Theory is the view that morality is somehow dependent upon God, and that moral
obligation consists in obedience to God's commands.
Divine Command Theory includes the claim that morality is ultimately based on the commands or
character of God, and that the morally right action is the one that God commands or requires.
The specific content of these divine commands varies according to the particular religion and the particular
views of the individual divine command theorist, but all versions of the theory hold in common the claim
that morality and moral obligations ultimately depend on God..
9. Nebular theory
This theory best accounts for the objects we currently find in the Solar System and the distribution of
these objects. The nebula started to collapse and condense; this collapsing process continued for some
time. The Sun-to-be collected most of the mass in the nebula's center, forming a Protostar.
A protostar is an object in which no nuclear fusion has occurred, unlike a star that is undergoing nuclear
fusion. A protostar becomes a star when nuclear fusion begins.
Most likely the next step was that the nebula flattened into a disk called the Protoplanetary Disk ;
planets eventually formed from and in this disk.
Three processes occurred with the nebular collapse:
• Temperatures continued to increase
• The solar nebula spun faster and faster
• The solar nebula disk flattened
The orderly motions of the solar system today are a direct result of the solar system's beginnings in a
spinning, flattened cloud of gas and dust.