With regard to the
creation of the universe (heavens and the earth) Allah (SWT) says in the
Qur'an:
Your Guardian
Lord
Is God, Who created
The heavens and the
earth (universe)
In six Days,
..............
Surah, A'RAF, 7:54
or
32: 4
Literal translation
gives the impression that the universe was created in six Days. The Arabic word
"Yaum" is translated as Day. Actually a 'day' of the people living on earth is
the time interval between each sunrise. During this time the earth makes one
complete rotation around its axis, while moving in an orbit around the sun
(which is a star). In this verse Allah (SWT) is referring to the conditions,
which existed before the sun or earth, were created. Hence the 'six days'
should not be interpreted in terms of earth days. For Allah "yaum" is equal to
billions of years or as short as one hundredth of a second or one atto-micro
second (10-18 X 10-6 = 10-24 second). The
relativity of time is mentioned in the Qur'an Hakeem (The Book of Wisdom) in
several verses. It is pertinent here to quote Abdullah Yusuf Ali, the most
popular translator of the Noble Qur'an in the English language with
commentaries. In note 1031 he says, " The creation in six Days is
of course metaphorical. The " Days of God" refer not so much to time as to the
growth in us of a spiritual sense, a sense of sin and a sense of God's Mercy.
In Surah, 22: 47, we are told that a Day in the sight of God is like a thousand
years of our reckoning and in Surah, 70: 4; the comparison is with 50,000 years
of our (earth) years. In the history of our material earth, we may reckon six
great epochs of evolution."
Hence the
concept of time is relative. The meaning of "Yaum" includes day, period of
time, interval of time, age, era, epochs of evolution or Time Frame.
The following
article describes the creation of the universe in six periods of time or "Time
Frames". This description is based on a theory of the early universe, which is
popularly known by astronomers as the "standard model." It is more or less same
thing as the "Big Bang" theory except that it contains the detailed recipe for
the contents of the universe.
At the end of
the article a Glossary of technical words is provided so that the readers may
refer to it in order to understand the meaning of the word.
At the beginning,
time was zero and space was zero and the temperature was infinite. Einstein
showed through his famous equation (E = mc2) that mass can be
converted into energy and energy can be converted into mass. Heat is energy,
and from energy particles of mass could be produced. Above a threshold
temperature of one billion degrees Kelvin (0° Celsius is equal to 2730
Kelvin), the universe would have contained a large number of particles called pi
mesons. Their mass is about one-seventh that of a nucleon (proton or neutron).
Nucleon is a particle that exists in the nucleus of an atom. A proton is a
positively charged nucleon, whereas a neutron is slightly heavier than the
proton but is electrically neutral. Unlike other particles, pi mesons interact
very strongly with each other and with the nucleons. The interaction of pi
mesons with the nucleons or nuclear particles is responsible for the nuclear or
attractive force that exists in the nucleus of an atom.
The behavior of
matter at super-high temperature is very difficult to predict. Hence the
interpretation of the creation of the universe starts about one-hundredth of a
second after the beginning (Big Bang) and the temperature was one hundred
billion degrees Kelvin (0° Celsius is equal to 2730 Kelvin).
FIRST DAY:
At this time the
temperature of the universe is one hundred billion degrees Kelvin (1011
°K). It is filled with particles and radiation, which cannot be
differentiated. The particles, which are continually being created out of pure
energy, are colliding with each other very rapidly. Although the universe is
expanding rapidly, the universe appears to be in a state of thermal
equilibrium. The contents of the universe are subject to the laws of
statistical mechanics. The temperature is extremely hot (1011 °K)
and the conserved quantities of particle physics such as charge, lepton number,
baryon number-are extremely small or zero.
The particles
that are present abundantly are the electron (the negatively charged particle
that flows through wires in electric currents and makes up the outer parts of
all atoms and molecules in the present universe) and positron (antiparticle of
electron which is a positively charged particle with precisely the same mass as
electron). In the present universe positrons are found only in high-energy
laboratories, in some kinds of radioactivity, and in violent astronomical
phenomena like cosmic rays and supernovas, but in the early universe the number
of positrons was almost exactly equal to the number of electrons, the massless
particles- the photons, neutrinos and antineutrinos (antiparticle of neutrino).
Neutrinos are ghostly particles with no mass or electric charge. At this time
the universe is extremely dense and even the neutrinos, which can travel through
the earth or through lead bricks without being scattered, are in a state of
thermal equilibrium with electrons, positrons, and photons by colliding with
them rapidly and with each other. They are behaving just like so many different
kinds of radiation. The energy density is calculated to be 21 X 1044
electron Volts per liter. This is equivalent to a mass density of 3.8 billion
kilogram per liter or to express in simple term's equivalent to 3.8 billion
times the density of water under normal earth conditions. Nobody has any
concept of what this huge density means. Suppose Mount Everest was made of
matter this dense, its gravitational attraction would destroy the earth. At
this time the universe is filled with light.
The universe on
the 'first day' is rapidly expanding and cooling. There are a small number of
nuclear particles (nucleons) at this time. About one nucleon (proton or
neutron) for every one billion (109) photons or electrons or
neutrinos. The neutron is slightly heavier than the proton. The few neutrons
or protons are colliding with the abundant electrons, positrons, and so on. As a
result of these collisions a proton is converted into a neutron and vice versa.
The reaction can be written as:
Proton +
antineutrino = neutron + positron (vice versa)
Neutron + neutrino =
proton + electron (vice versa)
There are almost
exactly the same number of neutrinos and antineutrinos, the same number of
electrons and positrons, so that the transition from neutron to proton is as
fast as the transition from proton to neutron. Because of equilibrium the
number of neutrons is equal to the number of protons on the 'first day.' These
nucleons are not yet bound into nuclei and any complex nuclei formed are
destroyed as soon as they are formed.
One is tempted
to ask the question how large was the universe on the 'first day.'
Unfortunately no one has the answer and this question has no meaning. If one
shows that the universe is infinite now, then one can argue that the universe
was Infinite then (at the time of 'first day), and will always be Infinite. On
the other hand it is possible that the universe now has a finite circumference,
which is estimated to be about 125 billion light years. This estimate is based
on the present value of the Hubble Constant. By taking the ratios of the
temperature then (1011 °K) to the present temperature (3° K), the
circumference of the universe on the 'first day' is calculated to be about four
light years (A light-year is the distance traveled by light in one year at the
rate of 300 million kilometers per second). The details of the story of cosmic
evolution (birth and formation of the universe) in the beginning do not depend
on whether the circumference of the universe was infinite or had only a few
light years.
SECOND DAY
Since the 'first
day' only eleven hundredths of a second (0.11 sec.) have elapsed. The
temperature of the universe has come down (cooled) to 30 billion degrees Kelvin
(3X1010 °K). Qualitatively nothing has changed- the contents of the
universe are the same such as protons, neutrons, electrons, positrons,
neutrinos, antineutrinos and photons, -all in thermal equilibrium. The energy
density has dropped to about 30 million times the energy density contained in
the rest mass of water. The expansion time of the universe has now lengthened
to about two-tenths of a second (0.2 second). The few nucleons (neutrons or
protons) are not bound into nuclei, but with the cooling of temperature it is
now significantly easier for the heavier neutrons to transform into lighter
protons than vice versa. The ratio of neutrons to protons or nuclear particle
balance has shifted to one-third neutrons and two-thirds protons.
THRID DAY
Since the
'first day' a little over one-second (1.09 seconds) have elapsed. The
temperature of the universe is now ten billion degrees Kelvin (1010
°K). The decreasing density and temperature have caused the neutrinos and
antineutrinos to behave like free particles and they are no longer in thermal
equilibrium with the electrons, positrons or photons. This is called the
"decoupling" of the neutrinos and they expand freely. They do not play any
active role in the formation of the universe, except that their energy will
continue to provide part of the source of the gravitational field of the
universe.
The energy
density is now reduced to a mass density of 380,000 times that of ordinary
water. The temperature of the universe is twice the threshold temperature of
electrons and positrons. The electrons and positrons interact with each other
to annihilate more rapidly than they can be created out of radiation (energy).
The temperature of the universe is still too hot for neutrons and protons to be
bound into atomic nuclei for any appreciable length of time. The cooling
temperature has now allowed the neutron-proton balance to shift to one-quarter
neutrons and three-quarter protons.
FOURTH DAY
Since the 'first
day' about 14 seconds have elapsed. The temperature of the universe is now 3
billion (3 X 109 °K) degrees Kelvin. The electrons and positrons are
beginning rapidly to disappear as major components of the universe. The
neutrinos are about 8 percent cooler than the electrons, positrons, and
photons. Here afterwards the temperature of the universe means the temperature
of the photons.
The temperature is
cool enough for the formation of stable nuclei such as helium (4He),
however this does not occur immediately. Now, ordinary helium (He4)
is a tightly bound nucleus. On the other hand the isotope (an atom having the
same number of protons but different number of neutrons) of hydrogen, tritium (3H),
and an Isotope of Helium- helium-3 (3He) are much less tightly 2
bound, and heavy hydrogen or deuterium (2H) is especially loosely
bound. (It requires about one-tenth as much energy to pull a deuterium nucleus
(which contains one proton and one neutron) apart as to pull a single nucleon
out of helium nucleus containing two protons and two neutrons). On the 'fourth
day' with a temperature of three billion degrees Kelvin, nuclei of deuterium
(heavy hydrogen) are blasted apart as soon as they form and there is no chance
for the formation of heavier nuclei. Neutrons continue to be transformed into
protons, but at a much slower rate than before. The neutron-proton balance is
about one-fifth neutrons to four-fifth protons.
FIFTH DAY
Since the 'first
day' three minutes and two seconds have elapsed. The temperature of the
universe is now one billion degrees Kelvin (109 °K), just about 70
times hotter than the temperature at the center of the sun. The main components
of the universe are now photons, neutrinos, and antineutrinos as the electrons
and positrons have mostly disappeared. When electron-positron pair annihilate
energy is released which increases the temperature of the photons by 35 percent
more than that of the neutrinos.
The temperature
of the universe is cool enough so that the nuclei of normal helium (Helium-4),
helium-3, and tritium hold together. One should remember that when a neutron is
free (not bound in the nucleus) it decays after 920 seconds or about 15 minutes
and becomes a proton. The collision between neutrons and protons with
electrons, neutrinos, and their antiparticles have now come to a stop, but the
decay of the free neutron is beginning to be important. The neutron-proton
balance is now one-seventh neutrons and six-sevenths protons. This period is
called "era of nucleosynthesis", as neutrons are rapidly assembled into helium
nuclei, and the neutron-proton ratio is frozen at the value it has at that time.
SIXTH DAY
Since the 'first
day' more than half-an-hour or 34 minutes and 40 seconds have elapsed. The
temperature of the universe is now 300 million degrees Kelvin or 21 times hotter
than the temperature at the center of the sun. Except for the small excess of
electrons required to balance the charge of the protons, the electrons and
positrons are now completely annihilated. The energy density of the universe is
now equivalent to a mass density one-tenth that of ordinary water; of this
one-third is in the form of neutrinos and antineutrinos and two-third is in the
form of photons. Nuclear processes have ceased, so that the nucleons are mostly
either bound into helium nuclei or are free protons (nuclei of hydrogen atoms).
There is one electron for each free or bound proton. Since the universe is too
hot, stable atoms cannot hold together.
For about one
million years, the universe goes on expanding and cooling without anything
happening. At that time the temperature would have cooled to the point where
electrons and nuclei can form stable atoms. Due to lack of free electrons in
the contents of the universe, the universe becomes transparent to radiation.
This era is known as the "Decoupling Era" - decoupling of matter and radiation.
The electron and-protons combine to form hydrogen and helium gases. The
resulting gas would begin under the influence of gravitation to form clumps,
which would ultimately condense to form galaxies and stars of the present
universe. After another 10 billion years later intelligent beings will emerge
to postulate the story of the origin of the universe.
GLOSSARY:
ANTIPARTICLE:
A particle with the same mass and spin as another particle, but with equal and
opposite electric charge, baryon number, lepton number, and so on. To every
particle there is a corresponding antiparticle, except that certain purely
neutral particles like the photon and pi-zero meson are their own antiparticles.
The antineutrino is the antiparticle of the neutrino; the antiproton is the
antiparticle of the proton; and so on. Antimatter consists of the antiprotons,
antineutrons, and antielectrons or positrons.
BARYON NUMBER:
It is the total number of baryons (neutrons, protons, hyperons) present in a
system, minus the total number of antibaryons.
CHARACTERSITIC
EXPANSION TIME:
Reciprocal of the Hubble constant. Roughly, 100 times the time in which the
universe would expand by one percent.
DENSITY:
The amount of any quantity per unit volume. The mass density is the mass per
unit volume. The energy density is the energy per unit volume; particle density
is the number of particles per unit volume.
ELECTRON:
The lightest massive elementary particle. All chemical properties of atoms and
molecules are determined by electrical interactions of electrons with each other
and with the atomic nuclei.
ELECTRON VOLT:
A unit of energy, convenient in atomic physics, equal to the energy acquired by
one electron in passing through a voltage difference of one volt.
GALAXY:
A large gravitationally bound cluster of stars, containing up to 1012
solar masses. A galaxy contains 200 to 300 billion stars.
HUBBLE CONSTANT:
It is the ratio of velocity of recession of moderately distant galaxies to their
distance, and is denoted H or Ho.
LEPTON:
A class of particles, which do not participate in the strong interactions, these
are the electron, muon, and neutrino.
LIGHT YEAR:
The distance that a light ray travels in one year, equal to 9.4605 X 1012
km
MESONS:
A class of strongly interacting particles: pi, K, rho mesons with zero baryon
number
PHOTON:
The particle associated with a light wave.
PROTON:
The positively charge particle found along with neutrons in atomic nuclei.
RECOMBINATION:
The formation of helium and hydrogen atoms at a temperature around 3000o
K
REST ENERGY:
The energy of a particle at rest, which would be released if all the mass of the
particle could be annihilated. Given by Einstein's formula E = mc2.
STRONG INTERACTIONS:
Responsible for the nuclear forces, which hold protons and neutrons in the
atomic nucleus.
THERMAL EQUILIBRIUM:
A state in which the rates at which particles enter any given range of
velocities, spins, and so on, exactly balances the rates at which they leave.
Any physical system will reach thermal equilibrium after a long time if left
undisturbed.
THRESHOLD
TEMPERATURE:
It is the temperature above, which a particle can be freely created out of
thermal radiation. It is the rest energy divided by Boltzmann's constant.
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