ATOMS IN THE UNIVERSE.

The entire Universe is made up of atoms. How many such atoms are there in the Universe?

As we know there are innumerable numbers of atoms everywhere. As an example the human body alone consists of 7 Octillion or 7 raised to the power of 27 atoms.

Now, there is a difference between the observable universe and the actual universe. As you well know the Universe is expanding and its origin the Big bang has taken place 1380 crore years ago. But the point is we are seeing today what started 1380 crore years back. During this period it would have expanded much more (as the expansion of the Universe is going at constant speed).

Matter comprises of only 5% of the Universe. The rest consists of Dark Energy and Dark matter, but they are not made up of atoms and therefore we need not take that into account for calculating the number of atoms in the Universe.

As per Einstein’s equation, mass and energy are interchangeable, but at any point in the Universe as a whole, the matter created and the matter destroyed cancel each other out, so the mass remains constant. That means the number of observable atoms in the Universe are constant all the time.

According to the observations of the known Universe, the physical laws that govern it are the same everywhere (at least to our knowledge). We know that the expansion of the Universe is constant which means that on a large scale matter is distributed uniformly throughout the Universe. This is known as the Cosmological Principle. This idea allows scientists to estimate the number of stars and galaxies in the observable universe.

Now we know that atoms are mostly in stars. But we have no means of knowing what is the extent of atoms that are present in planets, moons and space rocks. But for estimation purposes the matter in stars is much larger than in these smaller separate bodies and therefore the mass of the minor bodies can be neglected in our calculation. This does deviate from our estimation, but the deviation would be minuscule.

Hydrogen atoms consist of about 90% of all atoms in the Universe. However, for simplifying things, we have to assume that all the atoms in the Universe are Hydrogen atoms.

There are about 10¹² stars in each galaxy and there are about 10¹² galaxies in the Universe. Therefore the total number of stars in the universe is 10²⁴. An average star weighs around 10²⁹ tons. Thus the mass of the Universe is 10⁵³ tons.

On an average 1 gram of matter contains 10²⁴ protons, so a ton of matter contains 1000*1000*10²⁴ protons or 10³⁰ Hydrogen atoms since the mass of the Electron is negligible compared to the proton.

Then the Hydrogen atoms in the Universe would be 10³⁰*10^53, or 10^83..

Now, this number is only a rough estimate based on certain assumptions. However, looking at the current understanding and observations, this would not be far off the mark.

See that mind numbing number which simply passes beyond our imagination.

Let alone our mind fathoming this number it fails even to understand the number of atoms in the human body which by itself is mind boggling. How can 10²⁷ number of atoms come together to form the various organs of the body and integrate it into an organism? Assuming that a single cellular organism first appeared and flourished in the seas, how did it slowly acquire the organs due to evolution and then grow into a multitude of species? It simply defies anyones imagination.

Astrobiology studies the origins, early evolution, distribution and future of life in the Universe.  It also studies as to whether life exists outside earth, and if it does, then as to how to detect it. It uses the multiple sciences of molecular biology, biophysics, chemistry, biochemistry, astronomy, geology, cosmology etc. for the purpose of its investigation.

BITS OF MY LIFE-MY FASCINATION FOR OLYMPICS.

How I got so interested in Olympics? Way back when I was about 13-14 years old, I happened to read a book on Olympics from my father’s library.  I still remember that books cover. It had a red cover with the statue of “Discobolus” or the Discus thrower of Miro depicted in white on top of the red background. 

Now, till that time no one talked to me about the Olympics so I did not even know what it was. That book fascinated me so much that immediately on reading it I decided that I should go to the Olympics. 

I had no idea what a stupendous task it can be, but at that youthful time it was sheer enthusiasm without any logical foundation for it. 

Somehow the javelin fascinated me and I decided that it would be the event that should be tried first. So I cut a piece of bamboo pole about 8 feet in length. Luckily the ancestral house where I stayed then had about 3 acres of grounds, some of which did not have any trees. I started throwing that bamboo pole from one side, then run to the other, measured it back and threw it again. 

It went on like that for some time when I thought I should diversify into other events. So in the morning I used to go religiously to the grounds (I must be around 14 at that time) and used to initially run for about 4 rounds of 400 mtrs each which I later extended to longer distances.

There was one school ground near to my house which had a high jump and long jump pits. But for doing high jump I needed the high jump poles. For that I cut two bamboo poles and struck nails into them so that the first nail came about 4 and half feet from the ground. After putting the poles into the ground I used another bamboo pole as the high jump bar between the poles by laying it on the nails on the poles either side. 

I used to do high jump, then cut another longer bamboo pole and even started doing pole vault. After completing my high jump and pole vault, I was running to the long jump pit and was doing long jump and triple jump as well. 

The school had an open ground and no boundary wall. To any stranger that passed by on the road, I must have been a strange sight, a guy all alone jumping away without another soul to accompany him. 

I never even bothered to ask any friend to accompany me. The enthusiasm and inspiration was so strong that it did not matter at all and I had to do it. I had a bicycle on which I ferried the poles each day back and forth between my house and the ground.  

Now practicing like a tinhorn in that manner and going to the Olympics is preposterous and impossible, but then, how was I to know that then? 

After sometime I thought I should also practice hurdles. So I paid some money to a ball picker from Engineering College and he obliged me by giving me about 10 hurdles from the College collection. After that it was an additional burden to me because on some days I used to ferry all those hurdles to the grounds in the morning and practice.   

My practice went on like that for about 6 months when a couple of friends joined me off and on. 

Of course I was also playing cricket then. Sometimes practicing regularly and sometimes not. Of course due to all these activities I became very fit, but did not have any impressive records because I was doing too many things. 

Even when I joined my engineering at Andhra University College of Engineering I continued my practice in the University grounds, although not with the same intensity as before. 

I hardly studied at college and some classmates were calling me  the athlete and some others the Javelin thrower. There were none in my college who could beat me in running (excluding the 100m and 200 m sprints), and jumps and Javelin. 

Of course I never thought of taking up shot put or discuss or hammer because of my frail frame and weight which then was just 52 Kgs. Somehow I could not do well in long jump and triple jump.

I was the champion of my college and used to win the 400, 800, 1500, 5000 & the 10000, and then High Jump, Pole Vault and Javelin. No one could even challenge me in these events. 

When I studied the Engineering degree was of 5 years duration. During that period, I represented my college in 5 inter collegiate and 5 Inter Engineering, i.e. a total of 10 meets, but I did not get any medals in the inter collegiate competitions but managed to get a couple of medals in Javelin throw in the Inter Engineering tournaments. I used to throw between 47 to 50 meters, my best being 49.75 mtrs with which I won a silver medal at the Inter Engineering meet at REC Warangal (now NIT). 

I remember that during that time the national record for Javelin was 74 meters and the state record of Andhra Pradesh was just 56 meters and with my frail frame and lack of focus I was throwing 50 meters. I was later elected as the General Captain of my college for 1 year.       

I could not do well in any single event because I did not focus on it and my energy was dissipated on multiple events. Surprisingly no one including my college physical directors ever advised me on taking up a single event. After college of course I could not continue the practice for obvious reasons.

Anyhow, that part of my life had been a sweet experience for me and I shall cherish it forever. I remember the time when the AU Engineering College Principal once told me during the years sports prize distribution “Krishnayya stand near the dais and do not go down because anyway all the medals are yours”. Such was my dominance at the college in athletics. 

MAHARANI SITADEVI OF BARODA

Sitadevi was born to the Raja of Pithapuram, Rao Venkata Kumara Mahipati Krishna Surya Rao in the year 1917 at Madras. 

                                             SITADEVI 

Sitadevi first married the EX VC of AU Sri M R Apparao garu, the Jamindar of Vyyuru, but was not happy with him as she was a big socialite and MR was not of that sort. 

Princess Niloufer the Nijams daughter in law was a close friend of Sitadevi. 

With MR, she gave birth to one son Vidyut Kumar Apparao also nicknamed as Tally. 

She met the Maharaja of Baroda Pratap Singh Rao Gaekwad in 1943 in the Madras race course. 

He was then considered as the 8th richest man in the world and the 2nd richest prince in India. 

The Gaekwad was totally taken in by her charm and fell for her badly. But he was then already married and had 4 children.

Moreover, his grandfather has set a rule in his state that no man should have 2 wives. Sitadevi also liked Gaekwad which perhaps may well be due to his riches.

 Gaekwad wanted to marry her but she was already married and could not expect a divorce from MR, so as per the suggestion of Gaekwad’s lawyers she converted to Islam by which act her earlier marriage was annulled. 

She then converted back to Hinduism and married the Gaekwad. Now the English felt the Raja has violated the law of the state on polygamy and summoned him. But he managed to convince the British on that. 

In 1946 Gaekwad took her on a tour of Europe and they bought a mansion in Monte Carlo in Monaco and Sitadevi took up residence there.

Gaekwad used to visit her often bringing the treasures of Baroda to Monaco. 

The couple made 2 trips to the US where they spent a cool 10 million dollars and that was in somewhere around 1950. 

The couple transferred priceless jewellery from the treasure of Baroda (you can find the list on Wikipedia page on Sitadevi, Maharani of Baroda) 

After independence our officials managed to get back some of the jewellery but the rest passed on to Sitadevi.

In 1994 the Indian officials managed to recover a pearl carpet in a Geneva vault. Currently the carpet is displayed at the Museum of Islamic Art in Doha. 

The Star of the South and other jewels of Baroda state which went to Sitadevi were with jewelers in Amsterdam. 

Sitadevi gave one son to Gaekwad named Sayaji Rao Gaekwad in 1945. She doted on her son, nicknamed him Princie and partied with international luminaries like Aristotle Onasis. Onasis had a big fleet of ships then and is considered as one of the richest men in the world 

In 1953 she sold her anklets to famous jewelers. The anklets had many large emeralds and diamonds. 

These jewels were used and a beautiful necklace was made by the jewelers which was sold to the Duchess of Windsor. 

In 1957 when the Duchess wore that necklace and went to a New York ball. Sitadevi was also present at the ball. 

While people were admiring beauty of the necklace of the Duchess, Sitadevi exclaimed that the jewels looked better on her feet. The Duchess was scandalized and returned back the necklace to the jeweler. 

Sitadevi was fond of cars and had a custom made Mercedes W126 for herself. She also had a Rolls Royce. 

We do not know the reason but she divorced Gaekwad in 1956. Prince Rainier of Monaco gave her and her son a citizenship of Monaco. 

After the divorce too she kept up her lavish lifestyle and ultimately she had to sell some of her jewels to maintain it in 1974. 

Unfortunately for her, her son committed suicide after his 40th birthday in 1985 due to alcoholism and drug addiction. It is a tragedy that her earlier son to MR also died of over consumption of alcohol.

Sitadevi died 4 years later in 1989.

See the way the lady lived and died which reads like a movie story. She sped through her life like a fast moving Comet. But then that is the way her personality is and perhaps that is the way she wanted her life to be.

JESUS CHRIST-ANOTHER NOTE

I had already written a note on Jesus once and posted in the group. This is an elaboration of that note.

Augustus Caesar was ruling the Roman Empire when Christ was born. He was succeeded by Tiberius Caesar who ruled when Christ was crucified. Tiberius was later succeeded by the notorious Caligula. 

As already mentioned in the earlier note, the life of Jesus comes from the 4 Gospels. Gospel means Good news. The gospels are not strictly biographies of Jesus but they are stories told in such a way to evoke a certain image of Jesus. They contain the theological reflections on Jesus and they are not eye witness accounts of what he had done.  Jesus started preaching only when he was 30 years old which means he hardly preached for 6 years before he was crucified.

Jesus was a penniless preacher and he wandered about the dusty sun bit country of Judea preaching his doctrine. He lived upon casual gift of food by the people.

What did Jesus preach? He preached the Universal Fatherhood of God and the coming of the Kingdom of Heaven. He must have had intense personal magnetism to attract his followers because he had no personal belongings, no money and no family backing either. He is said to be of delicate physique and died much before the 2 thieves who were also crucified along with him.

Christianity then was a very bold doctrine in Judea. The Jews believed in a humanlike God who had made a bargain with their father Abraham about them. When Christ preached their teachings have been hopelessly left behind. He taught that God was no bargainer and there were no chosen people for him and no favourites in the Kingdom of Heaven.

Jesus had scorn for the natural tendency to glorify our own people and minimize the righteousness of the other creeds and other races. Thus Jesus appears very tolerant and did not scorn other religions. It is rather unfortunate that the Christian preachers we see today in India go contrary to this. Jesus’s teachings have been distorted in practice by his followers like the same way it happens in all religions.

God is the loving father of all life he said, and is as incapable of showering a favour as the Sun. He said all men were brothers and were sons of the Divine father. While he was talking to people one day his mother and siblings came to visit him and this was conveyed to him saying that his brethren was waiting for him outside. He then said to his audience, who is my mother and who is my brethren? He then stretched his hands towards the audience and said you are my mother and brethren. For whoever shall do the will of my father who is in Heaven, the same is my brother and sister and mother.

Now the Jews had very strong family ties and they were outraged with the teachings of Jesus who said everyone is family. Christ condemned all the gradations of the economic system, all private wealth and personal advantages. So that actually means Jesus liked Communism. Of course he said everyone is equal and free, but Communism in the world has taken away the freedom.

As per Jesus all men belonged to the Kingdom, all their possession belonged to the Kingdom, the righteous life is for all men, and the only righteous life is the service of God’s will with all that we had and all that we were. I can see some similarity here to the Bhakti movement of Ramanuja and the Alwars. All these concepts of Jesus are of course got by us from the Gospels.

As already mentioned in the earlier note, there are 4 Gospels that are found in the New Testament and they are 1. Mathew, 2. Mark, 3. Luke & 4. John. The first 3 are referred to as the Synoptic Gospels as they give the story of Jesus in a similar way. Of these Mark is the oldest being compiled somewhere between 70 and 75 AD 40 years after the Jesus Christ was crucified. Mathew and Luke depend on Mark. The latest of them is John which was compiled between 80 and 95 AD.

As per L Michael White, Professor of Classics and Director of Religious Studies Program of the University of Texas at Austin, the gospels are not biographies in the modern sense of the word. Rather, they are stories told in such a way as to evoke a certain image of Jesus for a particular audience. They're trying to convey a message about Jesus, about his significance to the audience and thus we have to think of them as a kind of preaching, as well as storytelling. That's what the gospel, the Good News, is really all about.

Thus all the 4 Gospels have been written by Evangelists and they reflect their respective community’s needs.

As per John Dominic Crossan, a professor Emeritus of Religious studies at De Paul University located in Chicago which is the largest Catholic University in the US, the Gospel of John is written for Jewish audiences.

Like Professor Michael white, he says that the Gospels do not merely report Jesus but they interpret Jesus and are for audiences because most of the Christians of that time were illiterate and cannot read. They can only learn from the preaching Evangelists and the Gospels are written by the 4 first evangelists for their respective people’s understanding.

As per Harold W Attridge who is the Lilian Claus Professor of New Testament at Yale Divinity School there are many statements in the Gospels which reveal tensions between the Christians and the local Jewish community. He says that this may well be the reason for the Christian anti-Semitism that developed later. Professor John Dominic Crossan reiterates this.

THE TAIWAN DISPUTE

Taiwan was formerly known as Formosa. Taiwan lies in the Pacific Ocean, about 160 Km from the South eastern part of the mainland China. It is 400 Km long and has a 145 Km width at the broadest point. It comprises of 86 islands.

In the 13^th century the Han Chinese fishermen started settling on the Penghu islands which are a part of Taiwan. Very few outsiders visited the main island of Taiwan till the 16^th century. Then it was visited by fishermen and traders from Fujian in China, and also both by Chinese and Japanese pirates.

The Dutch East India Company tried to set up an outpost on Penghu islands of Taiwan but was driven away by the Ming forces from China. Finally in 1624 the company managed to set up a stronghold called Fort Zeelandia in Taiwan. When they arrived they found the area to be peopled by about 1500 Chinese. The company encouraged the Chinese from Fujian to settle there and work on Dutch plantations. By the 1660’s 50,000 Chinese were living on the island.

In 1626 the Spanish came in and made Northern Taiwan their base. But by 1642, the Dutch overthrew the Spanish.

After the Ming dynasty fell in 1644 in China, a vassal king was pressurized by the incoming Qing dynasty and shifted his base to Taiwan and in the process expelled the Dutch from Taiwan.

The Dutch now aligned with the Qing dynasty of China. They took a part of Taiwan and made a base but could not make any further progress and withdrew from Taiwan altogether in 1668.

In 1683 the Qing dynasty of China finally annexed Taiwan and ruled till 1895. Japan took Taiwan after a war with China in 1895. A group of high officials loyal to the Chinese Qing dynasty proclaimed the Republic of Formosa in 1895 against the Japanese rule and there was guerrilla resistance to the Japanese in which 14000 Taiwanese were killed. However, the rebellion against the Japanese was not successful.

In October 1944 during the 2^nd world war, the Formosa air battle was fought between the US carrier forces and the Japanese forces in Taiwan. During the war, many Taiwanese joined the Japanese forces.

However, after the war was over, most of Taiwan’s Japanese numbering around 300,000 were expelled to Japan. The Chinese forces assisted by teams of US forces landed in Taiwan and captured it. Later Despite handing it over to China, the allies considered Taiwan to be under the Japanese till 1952 the treaty of San Francisco as per which the possession of Taiwan passed on to China.

However, there was a problem for the transfer because in 1949 there was a communist revolution in China and the Nationalists led by Chiang Kai Shek were defeated. Chiang took about 2 million of his followers and migrated to Taiwan adding to the already present 6 million population there. He then formed a Republic of China (ROC) government there.

Now the problem for Japan is whether to hand over Taiwan to the Peoples Republic of China (PRC) or to the Republic of China (ROC) government? China did not attend the signing of the treaty of San Francisco and Japan surrendered the areas to Formosa without actually specifying to whether the surrender was to ROC or PRC.

Taiwan always claimed mainland China while the mainland China in turn claimed Taiwan. But, as you can see, right from 1895 onwards Taiwan had never been a part of China. That is 127 years till now. Yes, it was administered by China for 300 years before 1895, but as long as it is not contiguous with China and the people are not willing to accept China then China should not interfere with Taiwan. Moreover, the forms of government adopted by both is diametrically opposite with one being a democracy and the other Communist.  

PRITHVIRAJ CHOUHAN.

Just now and Akshay Kumar film on Prithviraj got released but turned out to be a flop. Movies are always dramatizations and need not necessarily depict reality. I do not know what is shown in this movie..... 

Prithviraj Chouhan had a very short life. He lived for just 26 years from 1166 to 1192. ... 

Prithviraj ascended the throne in 1177 when he was just 11 years old ..... 

On ascending his throne he had to face a rebellion from his cousin Nagarjuna but the rebellion was brutally crushed. The kingdom of Bhadanakas has been a persistent threat to his kingdom and he defeated them comprehensively sometime before 1182 AD when he was just 16 years old.....then in 1182 he defeated the Chandelas....again at the age of just 16.......he also fought some battles with the kingdom of Gujarat in which he was successful and then took on Jaichandra of Kannauj who in turn successfully resisted his expansion...... 

Chand Bardai has written in his " Prithviraj Raso" that Prithviraj has fallen in love with Jayachandra's daughter Sanyogita (Samyukta) and Prithviraj finally abducted her from Jaichandra but with her consent ..... however the  historical authenticity of this story is questionable......but Sanyogita (Samyukta) is certainly Jaichandra’s daughter and was the wife of Prithviraj. 

Now Jaichandra is a Gahadavala prince and he ruled from Kannauj whose territories are adjoining those of Prithviraj. He is a very ambitious prince like Prithviraj and therefore always opposed him. He remained a staunch rival of Prithviraj right till the end which actually means the story of the abduction of Sanyogita may well be true. Otherwise who would persecute his own daughter’s husband?

 Mohammed Ghori is from Ghur in Afghanistan and he first took Sindh, Multan and the Punjab . Prithviraj's borders touched the Ghur empire and there were raids by Mohd Ghori's troops on Prithviraj's territories which made Prithviraj attack Mohd Ghori in 1191 at the first battle of Tarain in which Mohd Ghori was seriously injured and his forces withdrew in disarray. Prithviraj made a blunder by not pursuing Mohd Ghori and finishing him off.

 Next year in 1192 AD, Ghori gathered a big army comprising of Persians, Afghans and Turks ....in this he used 10,000 mounted archers to harass Prithviraj's front lines....when elements of Prithviraj's army broke up from the main body on account of the mounted archers to pursue them, then Ghori's heavy cavalry finished them off.....these change in tactics compared to the first battle confused Prithviraj's forces and they were routed......Prithviraj left the battleground but was pursued, captured and executed.

 The name of Jaichandra is generally mentioned for treachery, but Jaichandra did no treachery and he merely opposed Prithviraj probably because Prithviraj married his daughter without his consent.

ISLAMIC KINGDOMS AND THE ADVANCEMENT OF SCIENCE.

The Roman Empire split into two in 286 AD by Emperor Diocletian. The Western Roman Empire had its seat of government at Rome and the Eastern Roman Empire had its seat of government at Constantinople from 380 AD onwards.

The Western Empire fell first in 476 AD but the Eastern Roman Empire continued and fell only in 1453, some 1000 years later when it was defeated by the Ottoman Turks.

In Arabia, a revolution was taking place. Mohammed had proclaimed a new religion and by converting them, united all the Arab tribes into one. After Mohammed the Rashidun Caliphate came into being which ruled from 632 AD to 661 AD. Under those 4 caliphs; Abu Bakr, Omar, Uthman & Ali expanded the Muslim empire to Iraq, Syria, Palestine, Egypt, Iran and Armenia.

Then in 661 AD came the Ummayed Caliphate in which the title of Caliphs was made hereditary and the Caliphate became secular unlike the Rashidun Caliphate which was based on theology. The Caliphate had its capital at Damascus and lasted till 750 AD. It was in  the Ummayed Sultan Harun Al Rashid’s court  that “One Thousand and One Nights” stories were compiled.

After the Abbasids became Caliphs in 750 AD, most of the Ummayeds in the Caliphate were executed, but some were exiled. After 6 years of exile, the Ummayed Abd Ar Rehman I became the Emir of Cardoba in Spain. He united all the small fiefdoms in Spain and extended his territory. Later, the Caliphate also spread into North Africa.  The Abbasids changed the capital from Damascus to Baghdad.

In 929 AD, the Ummayed Emir Abd ar Rehamn III declared himself as Caliph and Cardoba had become a Caliphate while the Abbasid caliphs were continuing at Baghdad.

The Caliphate was very diverse ethnically, religiously as well as culturally.

The Muslims of Arab descent held the positions of rulers and priests. Other Muslim converts were soldiers. Jews comprised of 10% of its population which is more than that of the Arabs. The Jews were in business and intellectual occupations.

There were also as many Berbers as Jews. The Christian minority were at the lowest rung of society, were heavily taxed and had few civil rights. During the Caliphate, the Jews had more freedom, affluence, and higher social standing. At the same time, the Jews were being terribly discriminated against in other parts of Europe then.

 The Muslim population of the caliphate rose to some 70% in Cardoba by the 11^th century, mostly made of converts. Both Christians and Jews had to pay the Jizya tax.

Science flourished under the Ummayyad Caliphs of Cardoba, the Abbasids of Seville, the Samanids, Ziyarids and Buyids of Persia in the period 786 to 1258 AD. During the same period, Europe was stagnating, did not progress, and was lying in theological darkness.

There were major developments in Astronomy, Mathematics, and Medicine. There also were minor developments in Physics, Chemistry, Botany, Zoology, Agronomy, Geography, Cartography etc.

The Arab mathematicians excelled in mathematics; Al Khwarizmi, Avicenna and Jamshid Al Kasi all from the Samanid Empire of Persia made advances in Algebra, Trigonometry, Geometry, and Arabic numerals (Of course these have travelled from India to them).

Doctors described diseases like Smallpox and Measles and challenged the classical Greek medical theory. Al Biruni, also from the Samanid Empire, Avicenna and others described the preparation of hundreds of drugs from plants and chemical compounds.

Al Biruni (973-1050 AD) lived at Ghazni in Afghanistan and was in Indologist and was well versed in Sanskrit. He traveled to India in 1017 AD and wrote “Tarikh al-Hind”(History of India) after exploring the Hinduism practiced in India. It is probable that through him the Arabic numerals have been passed on to the Arabs from India.  He was proficient in Persian, Arabic, Sanskrit, Greek, Hebrew and Syriac.

Ibn Al Haytham from the Fatimid capital of Cairo, Al Biruni, and others studied optics and mechanics as well as Astronomy. Science flourished around the Mediterranean Sea for several centuries.

EXPANSION OF ISLAM.

The top 4 religions of the world are 

1. Christianity with 2.38 billion followers, 

2. Islam with 1.91 billion followers, 

3. Hinduism with 1.16 billion followers 

4. Buddhism with 507 million followers. 

While Christianity spread with the Roman Empire, Islam spread with the Caliphate. 

Prophet Mohammed was born in 570 AD in the Quraish tribe of Arabia. He died in 632 AD. 

When he died he left no successors to him, but his tribe the Quraish elected his close follower and relation Abu Bakr as the 1st Caliph. Caliphs were both the religious and political heads of the Muslims. 

Then Omar, Uthman and Ali followed in his succession.  All these four Caliphs were related to Mohammed through marriage. 

Some of Mohammed’s followers felt that Ali, the son in law of Mohammed should be the first Caliph.

As Abu Bakr was elected, there was schism in Islam and those who supported Ali’s candidature had a slightly different philosophy and are known as Shias and the rest are Sunnis. 

These 4 Caliphs were together called the Rashidun Caliphs and the Caliphate as the Rashidun Caliphate. It prevailed between 632 AD to 661 AD, a period of just 29 years. 

Under Mohammed the Muslim state contained the entire Arabian peninsula. The Muslim state expanded during the Rashidun Caliphate from Arabia to Iraq, Syria, Palestine, Egypt, Iran and Armenia. 

These areas were conquered by the Caliphate from the Sassanid Empire of Iran. 

The Rashidun’s ran a theocratic empire which was later secularized by the Omayyad Caliphs who succeeded them. 

Till the time of Omayyad’s the Caliphs were elected if only by a few people. From the Omayyad’s they became a dynasty of succession. 

They Omayyad's had their capital at Damascus and had 14 Caliphs before the Abbasids succeeded them in 750 AD and had their capital at Baghdad. 

The Abbasids had 38 Caliphs and the Abbasid dynasty fell to the Mongols in 1258 AD. 

The Omayyad’s expanded the Caliphate to Transoxiana (parts of the Asian republics of Soviet Union), Sindh, North West Africa (Algeria, Libya, Mauritania, Morocco and Tunisia) and also Spain. 

At its greatest extent the Omayyad Caliphate covered an area of 11,100,000 Km which is a large empire.

After the Abbasids, there were titular Caliphs at Cairo under the Mamluks (a dynasty instituted by a slave soldier of the Muslim armies of the Caliphs) from 1258 AD to 1517 AD when the last Mamluk Caliph was captured by the Ottoman Sultan Selim I. 

The Ottoman Sultans then used the title of Caliph and held it till the Republic of Turkey was established in 1924. 

Thus the Caliphate lasted for 1292 years after Mohammed’s death in 632 AD.