Big bang cosmology

BBIIGG--BBAANNGG CCOOSSMMOOLLOOGGYY ::
SScciieennttiiffiicc&& RReelliiggiioouuss VViieeww PPooiinnttss
H.S. VIRK
Professor Emeritus, Indian Institute
of Science and Religion, Pune

Cosmological Ideas before Einstein
Aristotlian Ideas: Universe consists of Terrestrial
and Celestial spheres, following different laws.
Newtonian Ideas: Newton considered the creation
of the Universe as an act of God; Space and
Time appear as absolutes and the Earth
occupies a unique position in the Universe.
Gas-Cloud hypothesis: Kant and Laplace consider
the creation of the Universe out of gases and
vapours such as hydrogen, methane, carbon
dioxide, cyanogen and water. The planets and
the sun were created out of the same nebular
gas medium.

General Theory of Relativity and
RELATIVISTIC MODELS OF THE UNIVERSE
Einstein’s general theory of relativity presented in
1915, is in reality a cosmological theory. Each
cosmological solution of the field equations of
Einstein gives us a model of the Universe, by
which is meant an account of the history of the
Universe. Of the many models available, only
one can be correct, as we have only one actual
universe. We will describe several models which
have been proposed till date.

EINSTEIN’S EQUATION
A cosmological model is intended to represent
the positions and motions of the clusters of
galaxies. The basic feature in the history of the
universe is the expansion. For relativistic
cosmological models, the expansion curve is
obtained from solutions of Einstein’s equation:
Rμν − ½ gμνR = −λ gμν
• Simple Solutions are given in Jayant Narlikar’s
book “Elementary Introduction to Cosmology”
University Press, Hyderabad

SSoolluuttiioonn ooff EEiinnsstteeiinn’’ss EEqquuaattiioonn
• We can get various models depending
upon the value of Lambda but we discuss
three Models based on the solution of
Einstein’s equation:
• Einstein-De Sitter or Parabolic Model
• Cycloidal or Elliptical Model
• Hyperbolic Model

Singular State and a job for God
The three models of the universe described
above all start from a condition of infinite density
which is called a singular state. What
happened before the expansion started?
Einstein’s equations break down at the singular
state and our models fail to explain the history
of the universe backward. The creation or
expansion of the universe from singular state is
referred to as ‘Big Bang’. Who created the
Universe?

Oscillating model: To get rid of the singular
states, the oscillating model has been proposed.
Each contracting period in the universe’s history
ends in a smooth transition to subsequent period
of expansion. The universe is infinite in time but
finite in space. There are no singular states and
hence no need of bringing in the creator. The
universe continues for ever following the cycles
of expansion and contraction.

GGaammooww’’ss ((abg)) TThheeoorryy
The Universe started from a very dense, hot
mass of neutrons which decayed into protons
and electrons. These combined to form
complex nuclei. The temperature during this
phase was 10,000 million degrees and most of
the heavy elements were built up in the first 30
minutes of the expansion. The abg theory fails
to explain the production of heavier elements
after helium. Lemaitre explains the big bang
from a primeval atom - an atom which contained
all the matter of the universe.

Relativistic Models with Cosmic Repulsion
• Einstein model: This was the first
cosmological model. To overcome gravitational
attraction, Einstein introduced a l term in his
field equations to bring in repulsion at
cosmological distances. This model is static
with its space curved and of finite volume.
• Eddington’s model: This model follows the
discovery that the Einstein model is unstable
by the suggestion that the universe as we
know it started from a disturbance of the
steady state. This model had already been
announced by Lemaitre in 1927.

Lemaitre believes his model to be a correct
representation of the real universe. In particular,
he has pictured the initial singular state as being
the explosion of the ‘primeval atom’ as
mentioned earlier.

Theory of Inflation
Evidence collected by Astronomers during the last 50
years (regarding cosmic background radiation and
redshifts) confirms the hypothesis of Expanding
Universe and is the basis of Big-Bang Cosmology.
Einstein-De Sitter Model is most appropriate to explain
Big-Bang version of the Universe provided Inflation
theory is incorporated in it.
Driving the Universe backwards, we can arrive at a
state of infinite density, with all the matter of Universe
compressed into a mathematical point, a singularity.
At the time of creation, the fireball of radiation/energy
and particles burst with enormous speed (>>c) which
can be explained by Inflation. The size of fireball at
singularity has been considered to be as big as a
basketball.

ALAN GUTH of MIT proposed Inflation theory. In
the first 10-35 of a second after creation started, all
the forces: Strong, E.M & Weak, were united as
a superforce, a symmetric interaction. The
symmetry-breaking phase transition of the early
Universe must have released enormous energy.
According to Inflation theory, this sudden release
acted like negative gravity, inflating the Universe
and doubling its size every 10-35 of second.
Inflation has become a Cosmological buzzword
during 1990’s in Big-Bang Cosmology. Age of
Universe is ~ 15 billion years.

Quantum physics allows the Universe to appear
out of nothing at all, as a so-called vacuum
fluctuation. Quantum Uncertainty allows creation
of bubbles of energy or pair of particles (e+ & e-)
momentarily before they disappear. Size of the
bubble was considered to be equal to Planck
length (10--3355 m). Chaotic inflation led to the
sudden expansion of the Universe out of a
quantum fluctuation. The seed of the Universe is
considered to be a ‘Magnetic Monopole’,
according to a new version of inflation theory.
Hubble Telescope may provide useful data to
clinch the issues in Big-Bang Cosmology.

Some Interesting FFaaccttss aabboouutt tthhee
UUnniivveerrssee
• Size of Universe = 80 billion light year
~ 1million billion billion km (0.76x1024 km).
• Universe contains 100 billion galaxies, each
having million-billion stars in it.
• Virgo Cluster has 1000 galaxies inside, some of
them are colliding.
• Black holes are present in the centre of galaxies.
• A star has a tendency to become a Black Hole if
its mass exceeds 5 Solar masses.

HYMNS oonn CCRREEAATTIIOONN iinn VVEEDDAASS
• In the beginning was Hiranyagarbha, The Seed of
Elemental Existence,The only Lord of all that was
born.
• The whole of this Universe is stationed in the
Omnipresent and the Omnipotent God .
• We see him in various forms.He brings to light all
these Worlds.Him they call the Kala(Time), Infinite,
pervading the Infinite Space.
• In this creation are held in balance the three regions,
terrestrial, interspatial and celestial, and the three
divine realms pertaining to body, mind and spirit,
provided with three eternal functions-physical,
mental and transcendental.

UUPPNNIISSHHAADDIICC VVIIEEWWPPOOIINNTT
• According to Dussen there are four views of creation
in Hindu philosophy based on Upnishadas:
• Matter is eternal and Purusha (creator) has always
been independent of God. God does not create the
matter but moulds it into creation as a potter maketh
the earthen pots.
• Purusha is the cause and creator of matter. But after
the creation, God does not interfere in its working
and it continues according to its own fundamental
laws.
• God himself transforms into creation i.e., changing
his Nirguna form into Saguna form.
• Creation is a play of Maya. It is a mere illusion. Only
God is real.

Semitic Religions
• According to the Holy Bible, the creation of
universe is the manifestation of God. The whole
process of creation was completed in six days.
The first book of Moses, called Genesis, opens
with the lines: In the beginning God created the
heaven and the earth.
• In 1650, Bishop Usher of Ireland calculated the
date of creation as 4004 B.C. according to the
‘Genesis’ story of the Bible. This date has been
pushed back by a long span that has elapsed
since the appearance of man on earth confirmed
by recent archeological find (Neanderthal man in
Europe).

Cosmology in Sikh Religion
The truth of primordial existence of God
before the creation of time and space is also
explained by Guru Nanak in Japu:
Awid scu jugwid scu]
hY BI scu nwnk hosI
BI scu]
Existed before the beginning of time and
space; Existed throughout the various ages
in the past; Exists in the present; and
Will exist in the future.

AAGGEE ooff tthhee UUNNIIVVEERRSSEE
According to the Hindu view, age of the universe is
infinite. There are innumerable Brahmas who are
employed in the process of creation. Each Brahma
has life-time of 100 years. On astronomical time
scale the year is much bigger than our solar year.
Some of the units are given below:
• 1 Maha Yuga = S+D+T+K (Four Yugas)
= 432x104 Solar Years
• 1000 Maha Yugas= Kalp=Day=Night (of Brahma).
• 1000 Maha Yugas = 14 Manvantar + 15 Junctions.
After working out the above relation, we can get:
• 1 Manvantar = 71x432x104 Solar years.

SSüünnnn aanndd CCrreeaattiioonn ooff UUnniivveerrssee
• The most original contribution of Sikh scripture is
in the field of cosmology. Before the creation of
the universe, Absolute Reality or God existed in
the Sünn phase, called adi sach by Guru Nanak.
When the creation starts, both time and space
are also created and this phase corresponds to
jugad sach. In Maru Solhe composition in
AGGS, the process of creation is explained in a
scientific manner corresponding to Big Bang
cosmology. The primordial state of existence of
God or adi sach is synonymous with the Sünn
phase as epitomised in AGGS.

Concept ooff SSUUNNNN iinn SSUUKKHHMMAANNII
• sloku ] srgun inrgun inrMkwr suMn smwDI
Awip ] Awpn kIAw
nwnkw Awpy hI iPir jwip ]
• AstpdI ] jb Akwru iehu kCu n idRstyqw ]
pwp puMn qb kh qy hoqw ] jb DwrI Awpn
suMn smwiD ] qb bYr ibroD iksu sMig
kmwiq ] jb ies kw brnu ichnu n jwpq ] qb
hrK sog khu iksih ibAwpq ] jb Awpn Awp
Awip pwrbRhm ] qb moh khw iksu hovq
Brm ] Awpn Kylu Awip vrqIjw ] nwnk
krnYhwru n dUjw ]1] {pMnw 290-291}

• suMn klw AprMpir DwrI ] Awip inrwlmu Apr
ApwrI ]
Awpy kudriq kir kir dyKY suMnhu suMnu
aupwiedw ] 1 ]
• pauxu pwxI suMnY qy swjy ]isRsit aupwie
kwieAw gV rwjy ]
Agin pwxI jIau joiq qumwrI suMny klw
rhwiedw ] 2 ]
• suMnhu bRhmw ibsnu mhysu aupwey ] suMny
vrqy jug sbwey ]
iesu pd vIcwry so jnu pUrw iqsu imlIAY Brmu
cukwiedw ] 3 ]
• suMnhu spq srovr Qwpy ] ijin swjy vIcwry Awpy
]
iqqu sq sir mnUAw gurmuiK nwvY iPir bwhuiV

• Guru Arjun, the fifth Nanak, describes the
primordial trance of God before the creation
process starts as a manifestation of God :
• For countless days, He remained invisible.
For countless days, He remained absorbed in
Sünn. For countless days, there was utter
darkness, and
Then the Creator revealed Himself.
 kyqiVAw idn gupqu khwieAw ]
kyqiVAw idn suMin smwieAw ]
kyqiVAw idn DuMDUkwrw Awpy krqw prgtVw ]
(AGGS, M. 1, p. 1081)

BBiigg-BBaanngg CCoossmmoollooggyy iinn AAGGGGSS
• Arbd nrbd DuMDUkwrw ] Drix n ggnw
hukmu Apwrw ] nw idnu rYin n cMdu n
sUrju suMn smwiD lgwiedw ]1] KwxI n
bwxI paux n pwxI ] Epiq Kpiq n Awvx
jwxI ] KMf pqwl spq nhI swgr ndI n nIru
vhwiedw ]2] nw qid surgu mCu
pieAwlw ] dojku iBsqu nhI KY kwlw ]
nrku surgu nhI jMmxu mrxw nw ko Awie
n jwiedw ]3] bRhmw ibsnu mhysu n koeI
] Avru n dIsY eyko soeI ] nwir purKu nhI

• jw iqsu Bwxw qw jgqu aupwieAw
] bwJu klw Awfwxu rhwieAw ]
bRhmw ibsnu mhysu aupwey
mwieAw mohu vDwiedw ]14]
ivrly kau guir sbdu suxwieAw ]
kir kir dyKY hukmu sbwieAw ]
KMf bRhmMf pwqwl ArMBy
gupqhu prgtI Awiedw ]15] qw kw
AMqu n jwxY koeI ] pUry gur qy
soJI hoeI ] nwnk swic rqy
ibsmwdI ibsm Bey gux gwiedw ]

• For billions of years, there was nothing
but utter darkness. There was neither
day nor night, nor moon, nor sun, but
the Lord alone sat in profound trance.
Neither there was creation, nor air, nor
water. There were no continents, nor
underwords, nor seven oceans, nor
rivers nor the flowing of water. There
was neither death nor time. There was
no Brahma, nor Vishnu or Shiva.

• When He so willed, He created the
world and supported the firmament
without support. He created Brahma,
Vishnu and Shiva and extended the
love of mammon. He founded the
continents, solar systems and
underworlds, and from the absolute
self He became manifest.

EExxppeerriimmeennttaall OObbsseerrvvaattiioonnss
• Radio telescopes have recorded
evidence for various components of
the expanding Universe. Star
formation out of the Gas Clouds in the
Galaxies is still going on. Evidence of
Supernova explosions, Pulsars,
Quasars, Neutron Stars and Black
Holes is provided by Radio
telescopes.

Big bang cosmology

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