The Lost City

Dwaraka- A LOST CITY RECOVERED -
Dwaraka was a western Indian city submerged by the sea right after the death of Sri Krishna. This was regarded as a grandiose metaphor, part of a story filled with great myths. But in the early eighties an important archaeological site was found at the site of the legendary city of Lord Krishna.
Situated in Saurashtra, at a point where the Gomti river meets the Arabian sea, it has acquired multifarious names down the ages: Dwaraka, the gateway to eternal happiness; Swarnapuri, the city of gold, Swarnadwarika, the golden gateway. Why is that the rediscovery of Dwaraka has not attracted the same degree of attention in the West, as that of ancient Troy by Heinrich Schliemann?Literary texts like the Mahabharata, Harivamsha and Purana contain traditions about the foundation of Dwaraka, its planning and glory. Before the legendary city of Dwaraka was discovered some scholars were of the view that the Mahabharata being only a myth it would be futile to look for the remains of Dwaraka and that too in the sea. Others held that the Kurukshetra battle was a family feud exaggerated into a war.Excavations done by Dr. S.R. Rao at Dwaraka prove that the descriptions as found in these texts are not to be discarded as fanciful but are to be treated as based on actualities as seen by their authors. The architecture of the old Dwaraka of Krishna is majestic and wonderful. The great poet Premanand has in his Sudamacarit described its splendid beauty and majesty. Dwaraka is mentioned as Golden City in Mahabharata, Skanda Purana, Vishnu Purana and Harivamsha.Interesting descriptions about its construction are found in Purana. «Fearing attack from Jarasangh and Kalayvan on Mathura, Sri Krishna and Yadavas left Mathura and arrived at the coast of Saurashtra. They decided to build their capital in the coastal region and invoke the Vishwakarma, the deity of construction. However, Vishwakarma says that the task can be completed only if Samudradeva, the Lord of the sea provided some land. Sri Krishna worshipped Samudradeva, who was pleased and gave them land measuring 12 yojans and the divine architect Vishwakarma build Dwaraka, a city in gold». Another story says that at the time of the death of Sri Krishna, who was hit by the arrow of a hunter near Somnath at Bhalka Tirth, Dwaraka disappeared in the sea.
The information and material secured through underwater excavation of Dwaraka corroborates with the references to the city of Dwaraka, made in various Sanskrit literary works. In Mahabharata, there is a specific account about the submerging of Dwaraka by the sea, which reads thus: «The sea, which had been beating against the shores, suddenly broke the boundary that was imposed on it by nature. The sea rushed into the city. It coursed through the streets of the beautiful city. The sea covered up everything in the city. Even as they were all looking, Arjuna saw the beautiful buildings becoming submerged one by one. Arjuna took a last look at the mansion of Krishna. It was soon covered by the sea. In a matter of a few moments it was all over. The sea had now become as placid as a lake. There was no trace of the beautiful city which had been the favourite haunt of all the Pandavas. Dwaraka was just a name; just a memory».The importance of the discovery of Dwaraka lies not merely in providing archaeological evidence needed for corroborating the traditional account of the submergence of Dwaraka but also indirectly fixing the date of the Mahabharata which is a landmark in Indian history. The Thermoluminiscence date of the pottery from Bet Dwaraka which is also connected with the Krishna legend is 3520 years Before Present. Identical pottery is found in the submerged city of Dwaraka. Thus the results have proved that the account in Mahabharata as to the existence of a beautiful capital city of Dwaraka of Sri Krishna was not a mere figment of imagination but it did exist.
Besides the sea-ports, there were renowned cities which were washed away by the rivers on whose banks they were situated. We may cite here the case of Hastinapura and Pataliputra, situated on the bank of the river Ganga and falling victims to flood-fury. The Mahabharata mentions that Hastinapura was washed away by the Ganga and consequently the Pandavas had to migrate to Kaudambi. Pataliputra which was the premier city of the land (agranagara) and the test of the excellence of all the cities in the words of Dandin, the author of the Dashakumaracarita, later became the worst victim of inundation. The submerged parts of these cities are to be treated as protected monuments and great treasures of the ancient heritage of India. If Dwaraka excavations throw a flood of light on the history of the city which was associated with the life events of Krishna, the underwater excavations of Ayodhya situated on the bank of the river Sarayu might yield valuable information about the historicity of Rama, his age and contemporary urban status.
Since 1983 the Marine Archaeology Unit of the National Institute of Oceanography is engaged in the offshore exploration and excavation of the legendary city of Dwaraka in the coastal waters of Dwaraka in Gujarat. Brief accounts of the findings of the underwater search for the lost city have appeared in 1987, Progress and Prospects of Marine Archaeology in India, and in 1988, Marine Archaeology of Indian Ocean Countries.A brief account of the discovery of the submerged city of Dwaraka of Mahabarata fame and the salient features of the structures exposed as a result of underwater excavation conducted at Dwaraka and Bet Dwaraka by the Marine Archaeology Unit of the National Institute of Oceanography under the direction of Dr. S.R. Rao from 1983 to 1987 appeared in 1988 (40 years of Research - A CSIR Overview). Offshore exploration of the legendary city at Dwaraka was resumed in 1988 and continued through 1990 (see the Journal of Marine Archaeology, 1990), further seaward of the Temple of Samudranardyana (Sea God) at Dwaraka with a view to trace the plan and extent of the port-city and the purpose of the massive stone walls built on the banks of ancient Gomati. It was also necessary to ascertain whether its architectural features were in conformation with the description of the city of Dwaraka given in the epic Mahabharata. A second object was to obtain more corroborative evidence for reclamation referred to in the epic. Thirdly, the nick point where the ancient Gomati river joined the sea had to be determined. Lastly, the cause of submergence of the city was another problem that needed further investigation.Dwaraka was a city-state extending upto Bet Dwaraka (Sankhodhara) in the north and Okhamadhi in the south. Eastward it extended upto Pindara. The 30 to 40 meter-high hill on the eastern flank of Sankhodhara may be the Raivataka referred to in the Mahabharata. The general layout of the city of Dwaraka described in ancient texts agrees with that of the submerged city discovered. Four enclosures are laid bare; each one had one or two gateways. The port Aramda on way to Bet Dwaraka was the first gateway in the outer fortifications. The bastions flanking gateways of submerged Dwaraka resemble those of Kusinagara and Sravasti carved on the Gateways of Sanchi Stupa. The prasada referred to in the epic must be the high fort walls of Dwaraka, a part of which is extant. The epic says that flags were flying in the city of Dwaraka. This can be corroborated by the stone bases of flag posts found in the sea bed excavation. Umashankar Joshi is of the view that antardvipa in the region of Kugasthali referred to in the Mahabharata must be Bet Dwaraka. The Bhagavata Purana says that before leaving his mortal frame Sri Krishna put the ladies and children in boats and sent them to Sankhodhara.The buildings built of smaller fraction stone blocks are razed to the ground leaving only small portions of the thick fort walls, bastions and protection walls (built with massive stones) which are too heavy to be moved by tides and currents. From the structural remains in Dwaraka and Bet Dwaraka waters, it is possible to visualise that the city-ports were large and well planned.Every significant antiquity that corroborates a statement of the Harivamsa is the seal bearing the motif of a three-headed animal representing the bull, unicorn and goat. The Harivamsha says that every citizen of Dwaraka had to carry a mudra as a mark of identifications The seal (mudra) found in the excavation belongs to 15th-16th century B.C.Nearly two decades after marine archeologists found the lost city of Dwaraka off the coast of Gujarat the state government continues to drag its feet on a proposal to establish the world's first underwater museum to view the remains of the city submerged in the Arabian Sea.
The proposal for the museum, submitted by the Marine Archeology Center of the National Institute of Oceanography in Goa, involves laying a submarine acrylic tube through which visitors can view through glass windows the ruins of the city said to have been be ruled by Sri Krishna, 3500 years ago.Discovered in 1981, the well-fortified township of Dwaraka extended more than half a mile from the shore and was built in six sectors along the banks of a river before it became submerged. The findings are of immense cultural importance to India.«The search for the lost city has been going on since 1930» — S.R. Rao, who is still actively involved in the excavations, told India Abroad. «It is only after marine archaeologists started exploring the sea-bed near modem Dwaraka from 1981 that the structural remains of the city were found».Rao said that if a fraction of the funds spent on land archeology were made available for underwater archaeology, more light could be thrown on Dwaraka, which had much archeological significance because it was built during the second urbanization that occurred in India after the Indus Valley civilization in northwestern India. Dwaraka’s existence disproves the belief held by Western archeologists that there was no urbanization in the Indian subcontinent from the period between 1700 BC. (Indus Valley) and 550 BC. (advent of Buddhism). As no information was available about that period, they had labeled it the Dark Period.«The findings in Dwaraka and archeological evidence found compatible with the Mahabharata tradition remove the lingering doubt about the historicity of the great epic. We would say Krishna definitely existed», said Rao. What is needed, he added, is the political will to reconstruct the cultural history of the Vedic and epic periods of northern India.Over 200 experts from 84 countries, who gathered under the aegis of UNESCO in Paris recently to examine a draft convention on the issue, unanimously agreed that underwater cultural heritage was in urgent need of protection from destruction and pillaging.In Dwaraka, Krishna is supposed to have built a mighty kingdom on a site selected for him by Vishnu’s learned ‘vahan’, Garud. The city he built is supposed to have extended over 104 kms. It was well fortified and surrounded by a moat, spanned by bridges, which were removed in the event of attack by an enemy.Archaeological excavations have unearthed artifacts that prove that modern Dwaraka is the sixth settlement of the name on this site. The earlier cities have been, at various times, swallowed by the sea. The waves of the sea still lap the shores of this famous town, lending scenic beauty to this important pilgrimage destination.The Dwarkadhish temple, dedicated to Sri Krishna, is the focal point of all pilgrimages. Parts of it date from the 12th-13th century and others from the 16th, but the Jag Mandir, its sanctum sanctorum, is supposed to be 2,500 years old. The hall in front is richly carved and supported by 60 massive pillars, each one hewn out of a single stone slab. Many of the sculptures date from the Maurya, Gupta and Chalukya periods. Some of the subjects are of Jaina and Buddhist origin. The temple is 157 feet high.Another important pilgrimage site in the ancient city of Dwarka is Gomti ghat. The myth attached to the original temple says that it was built overnight at the instructions of Vajranabh, the great-grandson of Krishna, by the divine craftsman Vishvakarma. Archaeologists are undecided about the date of construction of the temple that exists now, but it is generally believed that it was rebuilt in the 10th or 11th century AD after the original temple was destroyed, probably during the Muslim invasions.Most of the temples and pilgrimage spots around Dwaraka are associated with Krishna and the Vaishnavite tradition. However, the temple of Somnath, which is not very far from this place, is dedicated to Shiva as Nagnath or Nageshwar Mahadev, and enshrines one of the twelve ‘Jyotirlinga’ which according to the Purana manifested themselves as columns of light in different parts of the country. The magnificent temple that stands there now is a replica of the original temple.An archaeological site, dating back to 7500 BC and older than hitherto oldest known human civilisations including those found in the Valley of Sumer, Harappa and Egypt, was discovered by a team of Indian marine archaeologists in the Gulf of Cambay off Gujarat coast. "For India, it was the first time that such an important discovery was reported from near Dwaraka site, the off-shore region where underwater archeological exploration was in progress", Union Minister for Science and Technology Murli Manohar Joshi said at a crowded Press conference. "Further investigation of this area was important as it might throw some light on the development of human civilisation, besides having a bearing on the Indian history", concluded Dr. Joshi.
In order to establish without any doubt wheter or not the ruins on the seabed are effectively of the city of Dwarka, a group of archaeological experts and Indian Navy divers are conducting a scientific survey off the Gujarat coast."We found building blocks and collected samples. These have been sent for dating to establish the antiquity of the site," Alok Tripathi of the Archaeological Survey of India (ASI) told, who is the ASI’s only marine archaeologist.A 21-member team conducted the survey in January-February 2007. It comprised 10 specialists from the ASI and 11 divers of the Indian Navy.«While the ASI has the requisite data and archaeological expertise, the Indian Navy has the necessary wherewithal and expertise for subsurface search, exploration and recovery of artefacts,» Rear Admiral, S.P.S. Cheema, assistant chief of naval staff, explained. "Before the excavation, naval divers were indoctrinated by ASI experts on the procedures and method to be followed during the investigation. These included aspects like documentation, controlled digging, and the retrieval, packaging and transportation of samples" Cheema said. "The idea was to achieve maximum extraction without damaging the environment," he added.Before commencing diving operations, a specialised naval hydrographic team systematically surveyed the area off Dwarka with the help of multi-beam sonar and side-scan sonar. The navy had deployed its survey ship INS Nirdeshak for this in November 2006."This enabled us generate a 3D model of the seabed so we could narrow down the area of search. We initially marked out a 200 metre by 200 metre area and eventually narrowed this down to 50x50 metre area, "Tripathi explained.

When to use your heart or your brain?

First before knowing the answer to this question, you should first get a clear picture of what heart orientated actually means. When you say that you are actually following your heart, it rhetorically means that you deliberately allowed emotions to take over your discretions or judgments. Even emotions are triggered by the brains, though; the real mechanism behind this is unknown. So, most of the times when emotions come into play, we tend to make the wrong decisions.
Intuition is totally a different thing.It is actually the subconscious part of brain trying to reach out, to be heard over your conscious mind, and it is mostly driven by belief and faith.So, in making very important decisions, an interaction between the subconscious and the conscious mind is important(both are in the brain) and henceforth, the compability of the two is unquestionable.
Then 'how about following your heart’? It is strictly not advisable to use this, but in some circumstances where you are required to speak the truth or to give out a value judgment truthfully, then this may become an important aspect as well.

How fast must you go to time travel?

Time relativity uh??
There was an experiment conducted somewhere in the 2002, where two observers were used. The first one was asked to wait in the airport and the other one boarded the plane.Both of them were supplemented with an atomic clock (the most accurate clock in the world with very high degree of precision), and the time elapsed for the guy to step of the plane is taken (may have been decided by the use of cell phone).Amazingly, it was found out that the static observer was 0.001 behind the guy who has been travelling. The percentage error of the atomic clock is too small to be significant, and therefore the hard to swallow truth is that time is indeed stretchable.
However, as you can see from the above example, even in the speed of an airplane, we would only yield a time delay of a hundredth of a second, and therefore in order to yield a greater elapse, a greater speed would be required and is proposed that, for a substantial time delay, speed of light will be the most favorable.

HOGWARTS SCHOOL OF WITCHCRAFT AND WIZARDRY

Guys and girls out there........
This article was written way before the 7th book came out.....but it is only that i am publishing it, due to some refrains.......hehehe. So, don't be skeptic about this.....
And it contains some of the predictions that I made for the 'upcoming' book......
Make sure you guys read it, and just see how accurate I was............





There are many theories lingering about the famous Harry Potter seventh series, Harry Potter and the Deadly Hallows, which certainly being awaited by most of the fans worldwide. What would happen to Harry Potter? Will he be able to thwart the Dark Lord or will he or not? The answers, not yet know. However, it is worth making some predictions and guesses which indeed would lighten up the hearts of those so curious that they would not stop discussing about it. So, here we are with some of it.

LILY POTTER
Lily Potter is definitely one of the most important characters that we would have to discus a bit before even looking at any other. By a matter of fact, the story would not take place if at the first place Lily did not protect Harry Potter when he was baby, in which will not give the trouble of finding and killing Voldemort because he himself not be alive. From the start of the story, J.K. Rowling had given great deal of emphasis on how Harry so similar to his mother in many ways. Harry is said to be looking exactly as James Potter and to have his mother’s eyes. Besides this, his mother is said to be very funny, very courageous, and very brilliant student by Professor Slughorn, the Potion Master in the Half Blood Prince. He also said that there could not be anyone as he could remember who do not like her as soon as knowing her. This selective preference by a great wizard is indeed something to be given a thought about, because it bears some significance in it. For an instance, Harry has the same characters as his mother except for the fact that he does not possess the touch in Potions like his mother. So, this leads me in making some conclusions about his mother. Firstly, his mother could be someone of great status such as the heir of one of the founders of Hogwarts, most likely Gordic Gryffindor. This however might not be true as we already know that Lily Potter is just a Muggle with gifted abilities. But the theory of being the heir of someone powerful could be swayed to James Potter instead, explaining the whereabouts of the invisibility cloak that he possessed and the uncanning ability for a wizard. Yet, this may not be true. But one thing for sure is that, the truth that we would know about Lily Potter in the future would be an extremely important piece of information.
Aberforth
Who is Aberforth? Many would wonder. The significance of Aberforth in the last book appeared to me, when Dumbledore died in the previous series, AS we all know, Dumbledore had been Harry’s greatest protection since he had been undeniably the only one the Dark Lord ever feared. Harry Potter is just going to turn to 17 in the next book, and this age would just depict to us how young and vulnerable Harry would be compared to Lord Voldemort. Harry, so far had been spoon fed with the information on Lord Voldemort and how things happened, because obviously, we would not expect a seventeen year old to know that much. However, Harry had proven many times of his capability when he many times had been able to defy Voldemort evil attempts. In my opinion, I believe that the author would introduce a new character (as she herself said that her favorites or Order of The Phoenix member is yet to come). Harry had missed out to learn a lot of valuable things about the magical world; in fact he does not know anything much about Dumbledore at all. So, rationally speaking, the one who would be able to enlighten Harry with this knowledge is ought to be very close to Dumbledore and a great wizard himself. So the best choice would be Aberforth, Dumbledore’s only brother. Indirectly, Aberforth may have been much of a help in the previous books if what I had stated above is true. Harry himself conceded on how familiar the bar man in the Hog’s Head had been to him (spectacled, tall and thin frame, with long white beard. These attributes certainly is familiar to Dumbledore). Besides this, Harry had said about how one of the rooms in the bar gives a disconcerting smell of goats. This particular statement may also refer to Aberforth, as he had been closely associated with goats during his schooling days, where he might be working out with bezoars (stone taken out from the stomach of a goat which has the superlative effect on most of the poisons in the world) for the Order secretly. Moreover, during the day in which Professor Sybill Trewalney made the prophecy about Harry to Dumbledore, she had been overheard by someone whom apparently passed the information to the Dark Lord as it concerns about his master’s destiny. However, that guy was not able to capture most of the things that had been said as, he was later got chassed out by the bar man after causing some commotion. This shows that the bar man had known about he importance of the prophecy and had done that in favor of Dumbledore (If he had not interrupted, Voldemort would have heard the whole prophecy).Further more, during the meeting between Voldemort and Dumbledore, Dumbledore had somehow impressed Voldemort by giving out his unexpected knowledge about his intentions of wanting to become a teacher in Hogwarts, which on other hand had been regarded as Dumbledore’s omniscient capabilities by Voldemort. Dumbledore simply replied that he has a very close friendship with the local bar man whom would take the trouble of informing any peculiar movements to Dumbledore. We ourselves know that Dumbledore does make a frequent visit to the Hog’s Head despite having a better one which is nearer, for a drink. These accounts certainly had convinced you about how close Dumbledore had been to this bar man, whom coincidently has the same features as Dumbledore.

R.A.B.

Who is this mysterious person? This person had obviously been a highlight in the previous book. He had said that he had been the first one to discover Voldemort’s Horcrux and that he was about to destroy it. He also mentioned that he would not be alive when Voldemort comes to retrieve the Horcrux. He certainly wanted to cause harm to Voldemort by replacing the potion in the goblet with some powerful poison, which unfortunately Dumbledore drank instead, draining out Dumbledore’s power (Dumbledore was right about Voldemort all the time even when he said that Voldemort would not want to kill the person who reaches his Horcrux, but would want to know the wizard who suppose to be great if he or she is capable of overcoming his obstacles. Bad luck for Dumbledore; someone had reached there earlier and replaced the potion). Is this R.A.B bad or good? Obviously, if he is trying to kill Voldemort, he would be in the same boat as Harry. One of the guesses of who is R.A.B is Aberforth. This is because according to Dumbledore, he said that only a very great wizard could get pass through the obstacles prepared by Voldemort, and in my opinion Aberforth surely has at least the slightest trace of the immense power that Dumbledore has, thus making him qualified to be called a great wizard. However, intriguing factors do exist, where if it is Aberforth, then why did not he tell to his brother about the Horcrux. Dumbledore was almost certain that he is the only one who knows about the Horcruxes, but he was clearly wrong. Besides this, the fact that Aberforth would refer Voldemort as the Dark Lord is almost implausible, because it means that he approves Voldemort dominance and superiority which makes him sound more like a Death Eater, which clearly he is not. Another possible guess of who this R.A.B would be is Regulus Black, Sirius Black’s brother.Regulus Black had turned his back at Voldemort just before his fall, where he was on the run. That means that Regulus Black was a Death Eater and would have possibility of calling Voldemort as the Dark Lord, because he is use to call like that. Moreover, the fact that this R.A.B. knows that he is about to die, shows that he had been already been the hunted, so he was just counting his days. The dubious factor in this case is that, one would doubt on the magnitude of power that Regulus Black could possibly possess .I personally do not think that Regulus Black would have such powers as to surmount the obstacles placed by Voldemort. But one thing for sure is that, we would later discover the identity of this R.A.B. .


Severus Snape

The most uncertain character that exists through out the story would definitely be Severus Snape. Many people including Harry and his friends are not convinced with his atypical history nor his present. Harry hates him because he as his father’s most detest enemy, the one who is responsible for his parents death, and the one who eventually killed Dumbledore. Conflictingly, Dumbledore has his 100% trust on Snape from the start. Dumbledore sometimes resorts in discussing confidential matters only with Snape despite knowing that Snape could be employing Occlumency against him, as he is highly accomplished in that. Dumbledore is pretty much convinced that Snape is spying over Voldemort on behalf of him and not the other way round. However, Harry had got the confirmation for his suspicions right after Dumbledore got killed that Snape is bad. But I do still believe that Snape is indeed good and serving in behalf of Dumbledore. There are several reasons to it. Firstly, Dumbledore would not be so stupid to let his weakness of believing the best of people to get over him. Dumbledore had shown reputation over his sharp alertness when he alone did not believe Voldemort when he was at school when everyone else believed. Dumbledore himself in every occasion, had proven beyond doubt that he was always correct even when he judged Voldemort’s potion before his death. In this case, we are looking at the precision in Dumbledore’s judgments in many things, thus clinging to that I believe that Dumbledore is correct about Snape. Secondly, Dumbledore is fully aware Voldemort’s reputation, being the most accomplished Legilimien in the whole world. Despite this fact, he was still willing to take the risk to send Snape which he believed to be in his side, as a spy against Voldemort. This substantially means that Dumbledore is also aware of Snape’s high accomplishment in Occlumency, and he believed that Snape Occlumency is indeed very good to the extent in which he would be capable to turn over the world’s best Legilimien. Thirdly, Snape was obviously giving lame reasons to Belatrix for her questions during their meeting in the Half Blood Prince. Snape did not kill Harry even in the end of previous book saying that Harry is reserved by the Dark Lord, even though he knows that he could be honored beyond anyone else since he had killed Dumbledore as well. This led me to think that there might be another reason of why Snape killed Dumbledore was merely because it was under Dumbledore’s order. Dumbledore may have asked to kill him if he was to encounter that such situation. The hatred that exists at Snape’s face the moment when he spoke out the AVADA KEDAVRA spell was perhaps because of him hating doing that at the first place. Furthermore, when Dumbledore said “Severus, please” may have not mean that he was pleading because he was afraid to die but it maybe because, he was insisting Snape to kill him. As we all know, Dumbledore is not the kind of a person who would be afraid to die as he himself had said that, being dead is something that his kind of wizard has been longing for ( told in the first book). So, after all, Snape might have been the good person all the while.

Are science and spirituality mutually exclusive?

No.
Science and spirituality are indeed mutually inclusive.
In this context, we don’t talk about science facts, because science facts can be deceiving at sometimes due to some experimental errors, and slanted observations, but in here we should rather look at science itself.Spirituality has often been associated with religion, and therefore the connection between science and spirituality has been obscured to many. Spirituality is about self realization, whereby, you learn about yourself (includes your inner self), and there are various ways in pertaining it, but all of the ways will strictly require us to know and get acquainted to science. For e.g.; meditation. Meditation is said to be the most ideal pathway into self realization and unraveling the true potential of oneself. But meditation is not a one step process, especially for those who intend to seek for the highest level of meditation. One should have dominance on his or her respiration, temperature, anxiety (by the regulation of hormones) and etc. All these are biological processes, a sub discipline of science. All these fascinating stuff, you will only be able to do it if you unlock your subconscious mind.
Therefore, science and spirituality co-exist together in a harmonious relationship, whereby the latter having an effect on another and vice versa.

What influence does the core have on Earth

hmm......
no one really knows in what manner the core influences the Earth,but there have several predictions of what use the Earth's core might be...
firstly, the core is made mostly composed of iron and nickel and therefore it should be highly dense.(with the added effect of the compression, even more so)Since, iron and nickel are highly magnetized, the core happens to be the most plausible explanation for the source of the Earth's magnetic field, i.e., the orientation of the poles. In some times in the past, there have been several events when the Earth magnetic poles reversed, but the reason to it is still unknown.
Secondly, the core might be very instrumental especially the formation of Earth's gravitational field. The essence of any celestial body's gravitational field should have initiated from the core. For e.g., as the hot gases and debris swirl rapidly, centripetal force is generated. As the centripetal force became larger, the debris and the hot gases became concentrated into a pinpoint whereby it is densely lithified. This lithified chunk of rock is the Earth. But one may argue that as soon as there is no spinning then the centripetal force cease to work, and therefore the Earth disintegrates. However this does not happen because, in a very very densed environment such as the core, time is said to have stopped, and therefore, the centripetal force instead of collapsing, the force is trapped and it is known as gravitational force today.

What is your perspective on why mass extinctions periodically occurred on our planet since the phenomenon of l?

There were two mass extinction throught out the Earth's history. The first, took place about 250 milion years ago(the transition period of Paleozoic-Mesozoic) and the second one was approximated to be about 65 million years ago(the transition of Mesozoic-cenozoic). For both of the incidence there have been some compelling evidences which point towards meteorite showers as the main reason of the extinction.
This is of course derived from the findings of the layer of sediments with an exceeding amount of iridium concentration, one in which can only be found due to cosmic activities(and therefore frequently associated with celestial bodies such as meteoroids).The second evidence leading to this breakthrough, is the location of impact itself.
The crater that was found in Mexico, was formed due to an meteorite impact 65 million years back and the crater found in the coast of Australia corresponds to the time in which the preceding mass extinction(250 million yrs) took place.
So, can we say that it was only due to meteor showers?No.
The meorite showers may have been catalyst or a synergist for more catastrophic events such as tsunami(and therefore caused flood), spontaneous volcanic eruptions acroos the globe(a common layer of volcanc ash of a certain depth was found out as well, and radioisotope dating indicated the years, which again, corresponds), and due to the combination of this myriad of events, the Earth's climate was modified.(Right after the fall of meteorites, the Earth must have been exceedingly hot but the thick volcanic ash contered off the effect, leading into a cooling process)