Modern Science is unable to explain the process of creation as of now. The Big bang theory and Steady State theory have many loop holes and they do not appeal to everybody. Anyways, I will not discuss Modern theories of creation here. I am going to state what Vedas say about creation. Vedas are the sacred text of Hinduism, just like Bible for Christanity. Creation has many aspects, and it is not possible to talk about them in this article, so I will talk only about different phases of creation. Chapter 2.5 and 3.10 of Srimada Bhagavatam deals with the process of creation. Note that the Puranas, Upanishads are also considered as part of Vedas, besides 4 main Vedas. Before stating the theory, let me clear that English language does not have exact equivalents of the terms used in Vedic literature. So, I am using the terms and language used by other translations although the exact interpretation can be understood by reading the original text in Sanskrit, or in similar languages like Hindi. To understand them completely, please refer to Chapter 2.5 and 3.10 of Srimada Bhagavatam. From now on, I will use SB to refer Srimada Bhagavatam, and BG for Bhagavata Gita.
Here is the theory:
There are three basic material modes (qualities) of nature: mode of
goodness
(Sattva), mode of passion (Rajah) and mode of ignorance (Tamah). (SB
2.5.18)
There are nine phases in creation
besides the one which naturally occurs due to the interaction of these
three
modes. In this article, we will mostly look into these nine phases.
Eternal
time is the primeval source of the interaction of the three modes of
material
nature. (SB 3.10.14, 3.10.11)
1. Of the nine creation, the first one is the creation of Mahat-tattva
which is the result of incarnation of Supreme God
(known as Karanarnavasayi Visnu).
Then time is manifested. And in
course of time, the three modes or qualities appear. Then, in the
course of
time, the three qualities interact resulting in further creation. (SB
2.5.22,
3.10.15). Note that time is created by Supreme God. So for him,
everything
(beginning, end) is occurring at the same moment.
2. Material activities are caused by Mahat-tattva's
being agitated. Thus, in the 2nd phase of creation, the false-ego
(Aham) is generated in which
the material ingredients,
material knowledge and material activities arise. (SB 2.5.23, 3.10.15)
3. The sense perceptions and elements
are created in 3rd phase of creation. Here are the details:
a.
From the darkness of false ego, the first of
five
elements, namely the sky (nabhah),
is generated. Its subtle form is the quality of sound,
exactly as the seer is in relationship with the seen.
b. In the course of eternal time, due to the transformation (reactions)
in the
sky, the air is generated with the
quality of touch, and by previous
succession the air is also full of sound.
c. In the course of eternal time, due to the transformations in the
air, the fire is generated, taking shape
with the sense of touch and sound.
d. In the course of time, due to the transformations in the fire, the water is generated, full of juice and taste.
As previously, it also
has form, touch and sound.
e. In the course of time, due to the transformations in the water, the earth (solid) generated with the sense of
odour. Thus, the qualities of
sense perceptions are fully represented in earth.
So the transformation took place in the following order: ether
(or sky) -> gas (air) -> fire -> liquid -> solid.
(SB 2.5.25-29, 3.10.15, BG 10.8)
4. The fourth creation is the creation
of knowledge and of working capacity. (SB 3.10.16) This can be
understood
as the laws of nature.
5. The 5th creation is that of controlling deities by the interaction
of the
mode of goodness, of which mind is
the sum total. (SB 3.10.17)
6. The 6th creation is the ignorant
darkness of the living entity, by which master acts as a fool. (SB
3.10.17)
Thus, after the creation of Mahat-tattva,
time was manifested. Then 3 qualities of nature emerged in it. Then
false ego
was created. Then due to mode of ignorance, matter (5 fundamental
elements) was
created. Then its knowledge, and different activities of material
knowledge
come into play. In other words, the powers that evolve matter, the
knowledge of
material creations, and the intelligence that guides such materialistic
activities were generated. Mind was created due to mode of goodness.
Sense
organs were created due to mode of passion.
When all these became assembled by force of energy of Supreme God, this
universe came into being. All the above
are natural creations by the "maya"
of the Supreme Lord. Then a demi-god (Brahma)
known as creator of the universe came into existence, who has the brain
like that of Supreme Lord.
7. The 7th phase of creation is that of the immovable
entities, like creepers, the trees with and without
flowers, pipe plants etc. They are of 6 kinds. (SB 3.10.19)
8. The 8th phase of creation is that of lower
species of life, like cow, goat, ass, mule jackal, tiger, birds
etc. They
are not intelligent species. (SB 3.10.21-25)
9. The 9th phase of creation is the creation of human
beings. In the human race, the mode of passion is very
prominent. Humans are always busy in the midst of miserable life, but
they
think themselves happy in all respects. (SB 3.10.26)
10. The 10th creation, which naturally occurs due to the interaction of
three
modes are the creation of the demigods.
They are of eight varieties: (1) the demigods, (2) the forefathers, (3)
the
asuras, or demons, (4) the Gandharvas and Apsaras, or angels, (5) the
Yaksas
and Raksasas, (6) the Siddhas, Caranas and Vidyadharas, (7) the Bhutas,
Pretas
and Pisacas, and (8) the superhuman beings, celestial singers, etc. All
are
created by Brahma, the
creator of the universe. (SB 3.10.28-29)
Any theory of creation is incomplete without estimating the age, shape and size of universe. Vedas say that our universe is about 155.52 trillion human years old, and its total life span is 311.04 trillion human years (which is equivalent to 100 years of Brahma). In Srimada Bhagwata 5.20.38, the diameter of the universe is quoted as 500,000,000 yojanas (1 yojanas is equal to approx 9 miles, so its 4.5 trillion miles). The shape of the universe is egg shaped (brahmanda = brahma+anda). It may be interesting to observe that distance traveled by light in one day (186,000,000 * 3600 * 24 =~ 16 trillion miles) is equal to the perimeter of (vedic) universe (approximating ellipse to circle, perimeter of universe = 4,500,000,000 * 3.1416 =~ 14 trillion miles).
References: I have given references from Srimada Bhagvatam and Bhagvata Gita. Their online versions can be found at http://vedabase.net/sb/en and http://vedabase.net/bg/en.