Koh-i-noor, a Mountain of Light

Koh-i-noor, a

Mountain of

Light

Weight: 108.93 carats

Cut: round brilliant cut diamond

There was a period when Indian diamonds were very famous the world over. These included the Koh-i-noor, Orlov, the Great Moghul, Darya-i-noor, Indore pears, Shah and Arcots. These were all part of the treasure houses of the great emperors of India. Today, they are all in the hands of outsiders.

The legendary Koh-i-noor has been in the eye of the storm ever since it left the hands of its original owners - a diamond which was never bought or sold, but changed many hands. Koh-i-noor has left a trail that speaks of greed, power, murder, mayhem and unhappiness.

According to all references, Koh-i-noor was never that great to look at in its early days. It was just another diamond that was dull, non-sparkling and a little yellow in appearance.

Many legends say that the Koh-i-noor was mined in India, and at least 4,000 years old. It received a mention in the 1300s, when it was named in the Baburnama. One account states that Babur got his hands on the diamond in Gujarat; another says he got it in the Deccan. But when Babur came to Agra in May 1526, the ruler Vikramaditya most likely gave him the great diamond. There is also evidence that his son Humayun carried a large diamond that his father had handed back to him at Agra and was known as Babur’s diamond for the next 200 years.

There are still so many unresolved questions surrounding the precious stone. Many believe that the Koh-i-noor was also the Great Mogul and that Babur's diamond was separate; others say the Koh-i-noor and Babur’s diamond were one and same, while the rest identified it with both Babur's diamond and the Great Mogul. Information gathered over the years shows that in fact, three diamonds existed: - the Great Mogul – was the Orlov, weighing 189.62 metric carats, in Kremlin; and Babur's diamond – was the Darya-i-noor, weight 175 gm and 195 metric carats, the Iranian Crown Jewels; and the Koh-i-noor re-cut, Crown Jewels, England.

When the peacock throne was handed over to Nadir Shah, the hiding place of this diamond was given away. A member of Mohammad Shah’s harem gave away the hiding place of Koh-i-noor. It is said that the Shah kept it hidden in his turban. So, Nadir Shah devised a plan - he ordered a grand feast to coincide with the restoration of Mohammed Shah to his throne. During the feast Nadir Shah suddenly proposed an exchange of turbans, a sign of brotherly ties and eternal friendship. Mohammed Shah was hardly likely to resist. After the exchange, Nadir Shah entered his private apartment only at night, where he unfolded the turban and found the diamond concealed within. When he set his eyes on it, he exclaimed "Koh-i-noor", meaning "Mountain of Light".

The next sixty years of its history are the most violent and bloodstained. The final owner was Maharaja Duleep Singh, son of Maharaja Ranjit Singh, in the backdrop of the two Sikh Wars leading to the annexation of the Punjab by the British. The hoisting of British flag was on March 29th, 1849 Lahore where Punjab was formally proclaimed a part of the British Empire in India. One of the terms of the Treaty of Lahore was:- "The gem called the Koh-i-noor which was taken from Shah Shuja-ul-Mulk by Maharajah Ranjit Singh shall be surrendered by the Maharajah of Lahore to the Queen of England."

Dr Sir John Login was entrusted with two charges: to take the Koh-i-noor out of the Toshakhana (the jewel house), and also the guardsmanship of the young Duleep Singh. It was formally handed over to the Punjab government of Sir Henry Lawrence (1806-1857), his younger brother John Lawrence (afterwards Lord Lawrence, the man who in February of 1859 would break ground on the future Lahore railroad station), and C.C. Mausel.

The Koh-i-noor sailed from Bombay in H.M.S. Medea. It was put in an iron box and kept in a dispatch box and deposited in the Government Treasury. For security reasons, this piece of news was suppressed, even among officers of the Treasury - and withheld from Commander Lockyer, the ship's captain. HMS Medea's voyage turned out to be a perilous one - cholera broke out on board in Mauritius and the local people demanded its departure. They asked their governor to open fire and destroy the vessel if it did not respond. After leaving Mauritius, a severe gale hit the vessel that lasted for about twelve hours. They reached Plymouth, England, where the passengers and the mail were unloaded, but not the Koh-i-noor, which was forwarded to Portsmouth.

From there, the two officers took the diamond to the East India House, handing it over to the Chairman and Deputy Chairman of the company.

The stone

Prince Albert (Prince Consort) and Sebastian Garrard stated that the Koh-i-noor was badly cut, it is rose-not-brilliant-cut. It was decided to seek the advice of practical and experienced diamond cutters. A small steam engine was set up at Garrard's shop, while two gentlemen, Messrs Coster, Mr. Voorzanger and Mr. Fedder, travelled to London to undertake the re-cutting of the diamond. The Koh-i-noor was embedded in lead, two weeks later, after examining the stone. Mitchell thought that it had lost nearly all its yellow colour and become much whiter. The re-cutting took 38 days and cost £8000 ($40,000). The final result was an oval brilliant diamond weighing 108.93 metric carats, which meant a loss of weight of just under 43 per cent. Its was now in stellar brilliant-cut, possessing the regular 33 facets, including the table, while the pavilion has eight more facets than the regular 25 bringing the total number of facets to 66.

In 1853, it was mounted on a magnificent tiara for the Queen, which contained more than two thousand diamonds. Five years later, Queen Victoria ordered a new regal circlet for the diamond. In 1911, Garrards made a new crown that Queen Mary wore for the coronation - it contained diamonds, among them the Koh-i-noor. In 1937, this was transferred to the crown made for Queen Elizabeth the Queen Mother, based on Queen Victoria's regal circlet and is set in a Maltese Cross at the front of the crown.

The controversy

The 20th century saw a war of words over Koh-i-noor and its rightful ownership. In 1947, the government of India asked for the return of the diamond. Also, the Congress Ministry which ruled Orissa staked claim to the stone, saying it belonged to the Lord Jagannath. Ranjit Singh's treasurer mentioned that it was the property of their estate. Pakistan's claim to the diamond was disputed by India. Shortly thereafter, a major newspaper in Teheran stated that the gem should to be returned to Iran.

Sir Olaf has pointed out that the Koh-i-noor had been in Mogul possession in Delhi for 213 years, in Afghan possession in Kandahar and Kabul for 66 years and in British possession for 127 years. Historically, it maybe difficult to pass judgement on the validity of the various claims, but on the other hand, from a gemological aspect, as a paper report said, the Indian claim is the most valid because it was in that country that it was mined.

The legend

Legend goes that Sun God gave this gem to his disciple Satrajit, but his younger brother Persain snatched it from him. A lion in the forest killed Persain and Jamavant took this gem from the body of Persain and delivered it to Lord Krishna, who restored it to Satrajit. Later, this jewel again came back into the hands of Lord Krishna as dowry when Satrajit gave the hand of his daughter Satyabhama in marriage to him. Lord Krishna gave it back to the Sun God .The Koh-i-noor came into the hands of numerous rulers till it was possessed by Porus, the king of Punjab, who retained the diamond after a peace treaty in 325 BC when Alexander left India.

Chandragupta Maurya (325-297 B.C.) became the next possessor and passed it on to his grandson Ashoka who ruled from 273-233 B.C. Later it slipped into the hands of Raja Samprati of Ujjain (Ashoka’s grandson). This jewel remained in the custody of Ujjain and the Parmar dynasty of Malwa. When Ala-ud-din Khilji (1296-1316A.D.) defeated Rai Ladhar Deo, the ruler of Malwa in 1306 AD, he acquired the diamond. From this stage up to the time of Mughal Emperor Babur, the history of this precious stone is lost once more. Koh-i-noor comes to light again in year 1526.

Humayun is said to have given the stone to the Shah of Persia for giving him refuge after he lost to Sher Shah. From 1544 to 1547, the Koh-i-noor remained in the possession of Shah Tehmasp of Iran. The Shah sent the Koh-i-noor along with other precious gifts to Burhan Nizam Shah of Ahmednagar (Deccan) for the rulers of the Deccan - Ahmednagar, Golkunda and Bijapur regarded the King of Persia as their religious head. This stone remained in the possession of the Nizam Shahi dynasty of Ahmednagar and the Qutb Shah dynasty of Golkunda in the Deccan for a period of 109 years. How it came back to the Mughals is another gap in history.

After Aurangzeb, this diamond remained consigned into the coffers of the Mughal treasury from 1707 to 1739 A.D. Muhammad Shah Rangila (1719-1748) used to carry this wonder diamond with him in his turban. Nadir Shah got hold of Koh-i-noor when he ransacked Delhi in the 1700s and it went to his successors, landing in the hands of the Afghan ruler Shah Shuja who handed it to Maharaja Ranjit Singh in 1813.

The Koh-i-Noor left the shores of India on April 6, 1850, and on reaching London on July 2, 1850, it was handed over to the Board of Directors of the East India Company. Sir J.W. Logg, the Deputy Chairman of the East India Company, presented it to Queen Victoria. The queen recorded in her journal: "The jewels are truly magnificent. They had also belonged to Ranjit Singh and had been found in the treasury of Lahore.... I am very happy that the British Crown will possess these jewels for I shall certainly make them Crown Jewels".

Many still await the many treasures which were “stolen” by the British Raj, and no one knows how long the wait will be. But today, if you happen to visit London, please make a stopover at Tower of London and look at the Crown Jewels for the Queen and the Koh-i-noor placed in her crown up front inside a Maltese cross.

Tesla's Tower of Power

Tesla's Tower of Power

In 1905, a team of construction workers in the small village of Shoreham, New York labored to erect a truly extraordinary structure. Over a period of several years the men had managed to assemble the framework and wiring for the 187-foot-tall Wardenclyffe Tower, in spite of severe budget shortfalls and a few engineering snags. The project was overseen by its designer, the eccentric-yet-ingenious inventor Nikola Tesla (10 July 1856 - 7 January 1943). Atop his tower was perched a fifty-five ton dome of conductive metals, and beneath it stretched an iron root system that penetrated more than 300 feet into the Earth's crust. "In this system that I have invented, it is necessary for the machine to get a grip of the earth," he explained, "otherwise it cannot shake the earth. It has to have a grip… so that the whole of this globe can quiver."

Though it was far from completion, it was rumored to have been tested on several occasions, with spectacular, crowd-pleasing results. The ultimate purpose of this unique structure was to change the world forever.

Tesla's inventions had already changed the world on several occasions, most notably when he developed modern alternating current technology. He had also won fame for his victory over Thomas Edison in the well-publicized "battle of currents," where he proved that his alternating current was far more practical and safe than Edison-brand direct current. Soon his technology dominated the world's developing electrical infrastructure, and by 1900 he was widely regarded as America's greatest electrical engineer. This reputation was reinforced by his other major innovations, including the Tesla coil, the radio transmitter, and fluorescent lamps.

In 1891, Nikola Tesla gave a lecture for the members of the American Institute of Electrical Engineers in New York City, where he made a striking demonstration. In each hand he held a gas discharge tube, an early version of the modern fluorescent bulb. The tubes were not connected to any wires, but nonetheless they glowed brightly during his demonstration. Tesla explained to the awestruck attendees that the electricity was being transmitted through the air by the pair of metal sheets which sandwiched the stage. He went on to speculate how one might increase the scale of this effect to transmit wireless power and information over a broad area, perhaps even the entire Earth. As was often the case, Tesla's audience was engrossed but bewildered.

Back at his makeshift laboratory at Pike's Peak in Colorado Springs, the eccentric scientist continued to wring the secrets out of electromagnetism to further explore this possibility. He rigged his equipment with the intent to produce the first lightning-scale electrical discharges ever accomplished by mankind, a feat which would allow him to test many of his theories about the conductivity of the Earth and the sky. For this purpose he erected a 142-foot mast on his laboratory roof, with a copper sphere on the tip. The tower's substantial wiring was then routed through an exceptionally large high-voltage Tesla coil in the laboratory below. On the night of his experiment, following a one-second test charge which momentarily set the night alight with an eerie blue hum, Tesla ordered his assistant to fully electrify the tower.

Though his notes do not specifically say so, one can only surmise that Tesla stood at Pike's Peak and cackled diabolically as the night sky over Colorado was cracked by the man-made lightning machine. Colossal bolts of electricity arced hundreds of feet from the tower's top to lick the landscape. A curious blue corona soon enveloped the crackling equipment. Millions of volts charged the atmosphere for several moments, but the awesome display ended abruptly when the power suddenly failed. All of the windows throughout Colorado Springs went dark as the local power station's industrial-sized generator collapsed under the strain. But amidst such dramatic discharges, Tesla confirmed that the Earth itself could be used as an electrical conductor, and verified some of his suspicions regarding the conductivity of the ionosphere. In later tests, he recorded success in an attempt to illuminate light bulbs from afar, though the exact conditions of these experiments have been lost to obscurity. In any case, Tesla became convinced that his dream of world-wide wireless electricity was feasible.

In 1900, famed financier J.P. Morgan learned of Tesla's convictions after reading an article in Century Magazine, wherein the scientist described a global network of high-voltage towers which could one day control the weather, relay text and images wirelessly, and provide ubiquitous electricity via the atmosphere. Morgan, hoping to capitalize on the future of wireless telegraphy, immediately invested $150,000 to relocate Tesla's lab to Long Island to construct a pilot plant for this "World Wireless System." Construction of Wardenclyffe Tower and its dedicated power generating facility began the following year.

In December 1901, a scant few months after construction began, a competing scientist named Guglielmo Marconi executed the world's first trans-Atlantic wireless telegraph signal. Tesla's investors were deeply troubled by the development despite the fact that Marconi borrowed from seventeen Tesla patents to accomplish his feat. Though Marconi's plans were considerably less ambitious in scale, his apparatus was also considerably less expensive. Work at Wardenclyffe continued, but Tesla realized that this his competitor's success with simple wireless telegraphy had greatly diminished the likelihood of further investments in his own, much grander project.

In 1908, Tesla described his sensational aspirations in an article for Wireless Telegraphy and Telephony magazine:

"As soon as completed, it will be possible for a business man in New York to dictate instructions, and have them instantly appear in type at his office in London or elsewhere. He will be able to call up, from his desk, and talk to any telephone subscriber on the globe, without any change whatever in the existing equipment. An inexpensive instrument, not bigger than a watch, will enable its bearer to hear anywhere, on sea or land, music or song, the speech of a political leader, the address of an eminent man of science, or the sermon of an eloquent clergyman, delivered in some other place, however distant. In the same manner any picture, character, drawing, or print can be transferred from one to another place. Millions of such instruments can be operated from but one plant of this kind. More important than all of this, however, will be the transmission of power, without wires, which will be shown on a scale large enough to carry conviction."

In essence, Tesla's global power grid was designed to "pump" the planet with electricity which would intermingle with the natural telluric currents that move throughout the Earth's crust and oceans. At the same time, towers like the one at Wardenclyffe would fling columns of raw energy skyward into the electricity-friendly ionosphere fifty miles up. To tap into this energy conduit, customers' homes would be equipped with a buried ground connection and a relatively small spherical antenna on the roof, thereby creating a low-resistance path to close the giant Earth-ionosphere circuit. Oceangoing ships could use a similar antenna to draw power from the network while at sea. In addition to electricity, these currents could carry information over great distances by bundling radio-frequency energy along with the power, much like the modern technology to send high-speed Internet data over power lines.

Are we not the only Earth out there?

Are we not the only Earth out there?

In the relatively new science of planet hunting, no find is more prized than finding a planet like ours, one that could support life. As of late August 2007, almost 250 exoplanets -- planets orbiting besides our sun -- had been found [source: BBC News]. The announcement of new planets has become almost routine; some don't even make it into the news. But we do periodically hear about exoplanets that seem similar to Earth or that scientists speculate may hold liquid water, one of the key ingredients for carbon-based life. How many of these Earth-like planets are out there, and are they really like Earth, or do we just hope they are? In this article, we'll take a look at some potential Earths and what they may tell us about the future of planet hunting.

Space Tourism and Space Exploration Image Gallery

Image courtesy NASA This artist's depiction shows a possible Earth-like planetwith a rocky surface, oceans and an atmosphere. See morespace tourism images.

In August 2007, scientists announced the discovery of a star which might have once had an Earth-like planet orbiting it. The star was a white dwarf called GD 362, and it's 150 light years from Earth, still within our galaxy. While no Earth-like planets appear to orbit the star now, the presence of asteroid debris can tell us something about a planet that likely once orbited the star.

The debris, which came from an asteroid that was once 125 miles long, showed little carbon and high levels of calcium and iron. That means the rocky material is much like the moon and the rock that makes up the Earth. The presence of this familiar material, scientists say, implies that an Earth-like planet may have orbited the star millions of years ago, before it became a white dwarf. The star also has rings similar to Saturn's, and some of the ring material may be from planets and other objects that were torn apart by the white dwarf's gravity.

GD 362's diameter is about half of the Earth's, but its mass is about that of the sun, making GD 362 far more dense than our planet. However, GD 362 started out as a star like the sun in our solar system. But when the star used up its fuel, it swelled up into a red giant and then ejected its outer shell. The center of that star then transformed into a white dwarf, at once very hot (more than 100,000 Kelvin) and very small. A white dwarf retains about half of its mass but becomes incredibly dense because of its small size. Our sun should become a white dwarf in about five billion years. The process will destroy Mercury, Venus and possibly Earth.

So how many other Earth-like planets are out there (or were out there)? No one knows, but many scientists believe that it's inevitable that other Earths will be found. One NASA scientist told BBC News that some scientists believe that nearly every star has Earth-like planets orbiting it [source: BBC News]. Of course, excitement around finding these other Earths is based on the idea that they may contain alien life or even, centuries from now, allow for far-flung human space colonies -- before our star explodes and destroys the Earth.

Other Possible Earths

One of the main goals of planet hunting is to find exoplanets that have the characteristics of Earthand may consequently contain life. One of the keys to this search is the Goldilocks Zone. Also called the habitable zone or life zone, the Goldilocks Zone is an area of space in which a planet is just the right distance from its home star so that its surface is neither too hot nor too cold. That means that the planet could possibly host liquid water.

Image courtesy NASA In surveying potential candidates for "new Earths," astronomerslook for traces of biological activity, such as the presence of oxygen.

Few planets have been found in the Goldilocks Zone, but in April 2007, European astronomers announced the discovery of one. It was also, at that point, the most Earth-like planet ever found. The planet, called Gilese 581c, is 12,000 miles in diameter, or not much larger than Earth (8,000-mile diameter). It orbits a massive red star called Gilese 581, located in the Libra constellation, 20.5 light years from Earth. Gilese 581c orbits its star very closely, completing an orbit in just 13 Earth-days. This short orbit would make a planet too hot for life, except that Gilese 581's surface temperature is 1/50th that of our sun.

Because it lies in the Goldilocks Zone, Gilese 581c's surface temperature ranges from an estimated 32 degrees Fahrenheit to 102 degrees Fahrenheit. The research team that discovered it believes it has a developed atmosphere. The planet might not only have water -- it might be entirely covered by oceans.

Gilese 581c does have some things working against it. Its gravity is about twice as strong as Earth's, and it receives significant doses of radiation from its star. Both could inhibit life from developing. Even so, Gilese 581c is exciting not only for its Earth-like conditions, but also because of its relative proximity to Earth and its location in the elusive Goldilocks Zone.

As more powerful and precise telescopes go into space, future efforts will involve examining exoplanets' atmospheres for traces of oxygen and methane and looking for rocky planets that lie in the Goldilocks Zone. Scientists are also increasing their use of automated telescopes that are programmed to look for minuscule variations in a star's brightness caused by an orbiting planet passing in front of it. With a rapidly increasing pace of discovery of exoplanets and a practically infinite number of stars in the universe, many other exciting discoveries are ahead of us.

The ideal discovery would be a planet similar in composition to Earth that lies within the Goldilocks Zone and orbits a stable star. But it's important to keep in mind that popular depictions of extraterrestrial life are likely wrong. Some life forms may be no more advanced than bacteria. Others may be highly advanced but unrecognizable, a thought that has caused some scientists to advocate the search for so-called weird life.

Does space have a shape?

Does space have a shape?

Centuries ago, human beings looked up at the night sky and imagined that a black globe enveloped the Earth. They believed the stars were simply pinpoints of light. The sun, moon and other planets circled the Earth in a regular, perfect pattern. In their minds, the universe was small, centered on Earth and organized into perfect spheres.

A diagram from the work of Copernicus showing how planets in our solar system move in relation to the sun.

Scien tists like Copernicus and Galileo discovered flaws in this philosophy. It took more than a century after Galileo's discoveries for the world to accept that the Earth wasn't the center of the universe. As time passed, we began to learn more about the universe. Today, we study the cosmos through advanced telescopes, satellites and probes.

Now we have images of galaxies<>

But what about the big picture? What do we know about the universe as a whole? Is it expanding? Is it infinite? If it isn't infinite, what lies beyond the boundary of space? And what exactly does space look like?

These questions fall under the category of cosmology, the study of the universe. People have tried many different approaches to study the universe. Some concentrated on mathematics. Others preferred using physics. And quite a few took a philosophical approach.

There's no consensus among cosmologists about what space looks like, but there are plenty of theories. Part of the challenge of describing space is that it's very difficult to visualize. We're used to thinking about locations in two dimensions. For example, you can determine your location on a map using longitude and latitude. But space has four dimensions. Not only do you have to add depth to the dimensions of length and width, you also must addtime. In fact, many cosmologists refer to this collection of dimensions as space-time.

Space is Big

According to Stephen Hawking, the observable universe spans a million million million million miles across. That’s a one followed by 24 zeroes [source: Hawking].

The Big Bang, Gravity and

General Relativity

Three theories that are instrumental in understanding the shape of the universe are the big bang, thetheory of gravity and Einstein’s theory of general relativity. Cosmologists consider all of these theories when forming hypotheses about the shape of space. But what exactly do these theories try to explain?

The spiral galaxy M100, as seen through the Hubble telescope.

The big bang theory is an attempt to describe the beginning of the universe. Through observation and analysis, astronomers determined that the universe is expanding. They have also detected and studied light that originated billions of years ago back when the universe was very young. They theorized that at one time, all the matter and energy in the universe was contained in an incredibly tiny point. Then, the universe expanded suddenly. Matter and energy exploded outward at millions of light years every fraction of a second. These became the building blocks for the universe as we know it.

SingularityGeneral relativity suggests that just before the big bang, a point with zero volume and infinite density contained all the matter of the universe. This phenomenon is called a singularity. Matter that enters a black hole also enters a singularity as its volume reduces to zero and its density increases to infinity [source:Hawking].

The theory of gravity states that every particle of matter has an attraction to every other particle of matter. Specifically, particles will attract one another with a force proportional to their masses and inversely proportional to the square of the distance between them. The equation looks like this:

F = GMm/r².

F is the force of gravitational attraction. The M and m represent the masses of the two objects in question. The r² is the distance between the two objects squared. So what’s the G? It’s the gravitational constant. It represents the constant proportionality between any two objects, no matter what their masses. The gravitational constant is 6.672 x 10^-11 N m² kg^-2 That’s a very small number, and it explains why objects don’t just stick to each other all the time. It takes objects of great mass to have anything more than a negligible gravitational effect on other objects.

If the big bang theory is true, then when the universe began there must have been a huge burst of energy to push matter so far so fast. It had to overcome the gravitational attraction among all the matter in the universe. What cosmologists are trying to determine now is how much matter is actually in the universe. With enough matter, the gravitational attraction will gradually slow and then reverse the universe’s expansion. Eventually, the universe could shrink into another singularity. This is called the big crunch. But if there’s not enough matter, the gravitational attraction won’t be strong enough to stop the universe’s expansion, and it will grow indefinitely.

What about the theory of relativity? Besides explaining the relationship between energy and matter, it also leads to the conclusion that space is curved. Objects in space move in elliptical orbits not because of gravity, but because space itself is curved and therefore a straight line is actually a loop. In geometry, a straight line on a curved surface is a geodesic.

The three theories described above form the basis of the various theories about what the shape of space actually is. But there’s no actual consensus on which shape is the right one.

What are the theoretical shapes of space, and why don't we know which one is right? Find out in the next section.

The Shapes of Space

The three main models of the universe are based on curvature: zero curvature, positive curvatureand negative curvature.

In this illustration you can see the three different curvature models space might have -- no curvature, positive curvature and negative curvature.

A zero curvature would mean that the universe is a flat or Euclidean universe (Euclidean geometry deals with non-curved surfaces). Imagine space as a two dimensional structure -- a Euclidian universe would look like a flat plane. Parallel lines are only possible on a flat plane. In a flat universe, there is just enough matter so that the universe expands indefinitely without reversing into a collapse, though the rate of expansion decreases over time.

If the universe has a positive curvature, it’s a closed universe. A two-dimensional model of such a universe would look like a sphere. It’s impossible to have parallel geodesics (straight lines on a curved surface) -- the two lines will cross at some point. In a closed universe, there is enough matter to reverse expansion. Eventually, such a universe will collapse on itself. A closed universe is a finite universe -- it will only expand to a certain size before collapsing.

Negative curvature is a little trickier to visualize. The most common description is a saddle. In a negative curvature model, two lines that would be parallel on a flat plane will extend away from each other. Cosmologists call negative curvature models of the universe open universes. In these universes, there’s not enough matter to reverse or slow expansion, and so the universe continues to expand indefinitely.

Does this mean space is shaped like a flat plane, a sphere or a saddle? Not necessarily. Remember that space-time is measured in four dimensions, which reduces the usefulness of two-dimensional examples. And there are many competing theories about what the ultimate shape of the universe actually is.

One possible shape is the triple torus. At first glance, the triple torus appears to be an ordinary cube. But each face of the cube is glued to the face on the opposite side. Imagine that you’re in a spaceship that’s flying inside a large cube. You head toward the top of the cube. You wouldn’t smash yourself flat once you made contact. Instead, you’d appear in a corresponding spot at the base of the cube. In other words, you’ve gone up through the top and came back in through the bottom. If you traveled far enough in any direction, you’d eventually come back to where you started. This isn’t that foreign of a concept, since on earth if you travel in a straight line, you’ll eventually come back to your starting point. You’ll just be very tired.

This illustration shows what dodecahedral space would look like to an outside observer, if such a thing were even possible.

Another shape is the Poincaré dodecahedral spherical shape. A dodecahedron is a 12-sided object. The Poincaré variation has surfaces that curve outward slightly. What’s puzzling is that the projected size of this universe is smaller than the area we can actually observe. In other words, our visibility exceeds the boundaries of the universe. No problem, say the cosmologists. When you look at a distant galaxy that would seem to lie beyond the boundaries of space, you’re actually experiencing the wrap around effect described above. The galaxy in question would really be behind you, but you’re looking through one face of the dodecahedron as if it were a window. If you could see far enough, you’d be looking at the back of your own head.

Dizzy yet? There are many other theoretical shapes the universe could take, but most don’t fit the evidence we have so far. What is that evidence, and how do we gather it? Find out in the next section

How to Measure Space

Optical telescopes let us examine objects within the visible light spectrum but are relatively weak tools. That’s because the light from distant galaxies can intercept clouds of particles and other bodies before reaching Earth. Other devices can measure wavelengths that fall well outside the visible spectrum. Many of the recent studies in cosmology focus on the cosmic microwave background (CMB). The CMB is radiation that the universe generated when it was only 380,000 years old By studying this radiation, cosmologists can draw conclusions about what the universe was like shortly after it began.

Using the Wilkinson Microwave Anisotropy Probe (WMAP), scientists made an interesting discovery about the CMB. They found that the variation in radiation wavelengths of the CMB stops at a certain point. In an infinite, unbounded universe, there would be no limit to the size of wavelengths. We would expect to see variation and frequencies at all sizes. It’s only in a finite universe or a very specialized infinite one that we’d expect to see a definitive cap on wavelengths.

Music to My Ears In harmonics, a plucked string produces a sound with a wavelength twice the length of the string. You couldn’t produce a sound with a wavelength longer than that. In space terms, the absence of longer radiation wavelengths leads some cosmologists to believe that the universe has a finite boundary.

As for expansion, cosmologists call the ratio of the amount of matter in the universe and the amount needed to stop expansion the density parameter. A density parameter greater than 1 would mean a closed universe -- there is more mass in the universe that would be needed to reverse expansion. A density parameter of 1 would mean a flat universe in which expansion slows but never truly stops. And a density parameter between 0 and 1 would mean an open universe that would continue expanding forever.

But we don’t know how much matter really is in the universe. The amount we can detect is relatively small -- 5 percent of the matter needed to reverse expansion. But there appears to be matter that we can’t see at all. Cosmologists have noticed that stars move in an odd way -- they behave as if there is more matter exerting a gravitational influence on them than we can detect. Some cosmologists theorize that this means there is a kind of matter we can’t see at all, called dark matter.

Visible, or baryonic matter

Dark Matter

Dark Matter

But is there enough dark matter to cause a big crunch? That is, is there enough matter in the universe to make up the balance and push the ratio to a 1 or higher? While cosmologists believe there is far more dark matter in the universe than observable matter, they estimate the combination of both visible and dark matter still only comes to about 30 percent of the amount needed to reverse expansion

Before the Big Bang? What happened before the big bang? It’s impossible to say. Scientists theorize that once you compress the matter of the universe into a singularity (a point with zero volume but infinite density), scientific laws can no longer apply. Since the laws of physics are moot, there is no way to know what, if anything, came before the big bang. Science can’t answer the question.

While we don’t know what the definitive shape of space is right now, research continues to bring us new information every day. And if space has boundaries, what lies beyond them? We don’t know, and we may not be capable of knowing.

Has science explained life after death?

Has science explained life after death?

In 1991, Atlanta, Ga. resident Pam Reynolds had a near-death experience (NDE). Reynolds underwent surgery for a brain aneurysm, and the procedure required doctors to drain all the blood from her brain. Reynolds was kept literally brain-dead by the surgical team for a full 45 minutes. Despite being clinically dead, when Reynolds was resuscitated, she described some amazing things. She recounted experiences she had while dead -- like interacting with deceased relatives. Even more amazing is that Reynolds was able to describe aspects of the surgical procedure, down to the bone saw that was used to remove part of her skull [source: Parker].

Near-death experiences:

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It is estimated that as many as 18 percent of people who have been resuscitated after cardiac arrest have reported a near-death experience.

What's remarkable (although not unique) about Reynolds' experience is that it is the combination of an NDE and an out-of-body-experience (OBE). HowStuffWorks has braved this territory on the edge of reality, explaining how near-death experiences work and how a person can have an out-of-body experience. Science, too, has made its own headway toward explaining these weird phenomena. Two studies on the separate aspects of Reynolds' experience were conducted in 2007. Each seems to explain how a person can have an OBE or a NDE, but do they hold up in explaining experiences like Reynolds'?

As many as 18 percent of people brought back from death after a heart attack said they'd had a NDE [source: Time]. While many religious adherents might not be surprised by these accounts, the idea that human consciousness and the body exist distinctly from each other flies in the face of science. A brain-dead person should not be able to form new memories -- he shouldn't have any consciousness at all, really. So how can anything but a metaphysical explanation cover NDEs?

A study from the University of Kentucky has quickly gained ground among scientists as possibly the best explanation for NDEs. Researchers there theorize that the mysterious phenomenon is really an instance of the sleep disorder rapid eye movement (REM) intrusion. In this disorder, a person's mind can wake up before his body, and hallucinations and the feeling of being physically detached from his body can occur.

The Kentucky researchers believe that NDEs are actually REM intrusions triggered in the brain by traumatic events like cardiac arrest. If this is true, then this means the experiences of some people following near-death are confusion from suddenly and unexpectedly entering a dream-like state.

This theory helps explain what has always been a tantalizing aspect of the mystery of NDEs: how people can experience sights and sounds after confirmed brain death. The area where REM intrusion is triggered is found in the brain stem -- the region that controls the most basic functions of the body -- and it can operate virtually independent from the higher brain. So even after the higher regions of the brain are dead, the brain stem can conceivably continue to function, and REM intrusion could still occur [source: BBC].