Andersen KG et al. The proximal origin of SARS-CoV-2. Nature Medicine, March 2020.

Cases of Covid-19 first emerged in December 2019, when a mysterious illness was reported in in the city of Wuhan, China. The cause of the disease was soon confirmed as a new kind of coronavirus, and the infection has since caused a large-scale epidemic and spread to more than 70 other countries. Coronaviruses are a large family of viruses that are related to a broad spectrum of illnesses, the first of which was the 2003 Severe Acute Respiratory Syndrome (SARS) epidemic in China. A second outbreak of severe illnesses began in 2012 in Saudi Arabia with the Middle East Respiratory Syndrome (MERS). On December 31 of 2019, Chinese authorities alerted the World Health Organization of an outbreak of a novel strain of coronavirus named SARS-CoV-2 causing severe illness. As of February 20, 2020, nearly 167,500 Covid-19 cases have been reported, though many milder cases have likely gone undiagnosed. More than 6,600 people have already died as a result of contracting this virus – and the numbers will be much higher when you will be reading this article. Chinese scientists sequenced the genome of SARS-CoV-2 very shortly after the epidemic began and made the data available worldwide. The analyses of genomic sequence data have shown that Chinese authorities rapidly detected the epidemic and that the number of Covid-19 cases have been increasing because of human to human transmission after a single introduction into the human population.

Recently, a group of scientists used this sequencing data to explore the origins of SARS-CoV-2 and how it has become the version that it is now. The scientists specifically focused on the genetic codes for spike proteins, the mechanical framework on the outside of the virus that it uses to grab and penetrate the outer walls of human and animal cells. There are 2 major parts of the spike proteins: the receptor-binding domain (RBD), a molecular hook that grips onto host cells, and the cleavage site, a molecular can opener that allows the virus to crack open and enter host cells. The scientists found that the RBD portion of the SARS-CoV-2 spike proteins mutated to effectively target a molecular feature on the outside of human cells called ACE2, a receptor normally involved in regulating blood pressure. The SARS-CoV-2 spike protein was exceptionally effective at binding to human cells, and the scientists concluded this could only be a product after a natural selection process and not the product of human-designed genetic engineering. This evidence was further strengthened by data on SARS-CoV-2’s backbone molecular structure. If someone were to engineer a new coronavirus as a pathogen, they would have constructed it from the backbone of a virus known to cause illness. But the scientists found that the SARS-CoV-2 backbone differed substantially from those of already known coronaviruses and mostly resembled related viruses found in bats and pangolins. These two features of the virus, the mutations in the RBD portion of the spike protein and its distinct backbone, basically ruled out laboratory manipulation as a potential origin for SARS-CoV-2. Based on their genomic sequencing analysis, scientists came up with two possible scenarios as the most likely origins for SARS-CoV-2.

In the first scenario, the current pathogenic state of SARS-CoV-2 has emerged naturally in non-human hosts such as bats or pangolins and then jumped to humans. Coronaviruses are well known to undergo genetic recombination. In fact, this is exactly how previous coronavirus outbreaks have emerged, with humans contracting the virus after direct exposure to civets (SARS) and camels (MERS). The researchers proposed horseshoe bats as the most likely reservoir for SARS-CoV-2 as it is very similar to a bat coronavirus. There are no documented cases of direct bat-human transmission so far, suggesting that an intermediate host was likely involved between bats and humans.

In this particular scenario, both of the distinctive features of SARS-CoV-2’s spike protein and the cleavage site would have mutated to their current pathogenic state prior to entering humans. In this case, the current epidemic would probably have emerged rapidly as soon as humans were infected, as the virus would have already equipped with the features that make it pathogenic and able to spread between people.

In the second proposed scenario, a non-pathogenic version of the virus jumped from an animal host into humans and after a mutation process it has acquired its current pathogenic state within the human population. For instance, some coronaviruses from pangolins, armadillo-like mammals found in Asia and Africa, have a spike protein very similar to that of SARS-CoV-2. A coronavirus from a pangolin could possibly have been transmitted to a human, either directly or through an intermediary host such as civets or ferrets.

In this scenario, only the cleavage site could have mutated within a human host, possibly via limited undetected circulation in the human population for months or maybe years prior to the beginning of the epidemic. The researchers found that the SARS-CoV-2 cleavage sites have similarities that resemble strains of bird flu that can transmit easily between people. In the case of SARS-CoV-2, such a virulent cleavage site could have been formed in human cells and soon the current epidemic got initiated, as the coronavirus would possibly have become far more capable of spreading between people.

At this point, it is almost impossible to know for sure which of the scenarios is most likely. If the SARS-CoV-2 entered humans in its current pathogenic form from an animal source, it raises the probability of future outbreaks, as the illness-causing strain of the virus could still be circulating in those animal populations and might come back to humans again. It is still noteworthy that a non-pathogenic coronavirus entering the human population and then acquiring properties similar to SARS-CoV-2, the second scenario, is less likely than the first scenario.

In conclusion, this study brings an evidence-based view to the baseless rumors and conspiracy theories that the SARS-CoV-2 was deliberately manufactured in a lab and concludes that the virus has emerged after a natural process that took place in multiple hosts over time. These genetic findings are also consistent with how SARS-CoV2 is currently behaving. The virus has a low fatality rate (1% to 3.4%) and does not seem to act like a bioweapon compared to pathogens such as anthrax or Ebola. Given the previous coronavirus epidemics and the persistence of the culture of eating exotic mammals in China and other parts of the world, the current COVID19 epidemic is unfortunately not a big surprise for scientists and experts. We have to take necessary measures to be more prepared for such outbreaks that may take place in future.

The heart is composed of four compartments: two atriums and two ventricles. The blood that reaches the heart first accumulates in the atriums. From here, it is sent to the ventricles. Afterwards, it is redistributed to the body by the contractions of the ventricles. The harmony of this process depends on the electrical currents in our hearts.

How is the electrical current formed?

There is a particular region in the heart called the sinus node. The sinus node is strip of a muscle that is 15 mm in length, 3 mm in width, and 1 mm in thickness, and is located in the right atrium of the heart. The cells of this strip are responsible for producing electrical currents, and are created in a different fashion from the rest of the cells that are responsible for producing contractions. This is where the electrical currents in our hearts are periodically produced. Every cell in the body contains elements such as sodium, calcium, potassium and chlorine that are electrically charged. The elements which are electrically charged are called ions. These ions also exist in the extracellular environment. The intra cellular and extra cellular concentrations of these ions are different from each other. This situation causes a difference in the electrical potential between the interior and exterior of a cell. This difference is called a membrane potential. Periodically, the membrane potentials of the sinus cells show sudden jumps – meaning they suddenly increase and then suddenly decrease. Since the cells are in close contact with each other, such a jump in the membrane potential of one cell triggers a jump in the membrane potential of another cell. The electrical currency that enables the contraction of the heart is produced by this continuous triggering of cells. On average, 70 electrical currents per minute are produced in the sinus node. These currents start being produced while a person is in the womb of their mother and continues their whole lifetime. The heart of an embryo starts beating while it is only 22 days old. However, the height of the embryo at this point has not even reached 1 cm. Isn’t it an amazing force that creates the beating heart of such a small embryo and keeps it going a lifetime?

How is the electrical current distributed?

Another node called the atrio ventricular node was created in between the atriums and ventricles in our heart. While the current coming from the sinus node is spread to the whole of the atrium, it is by this node that the current is sent to particular fibers. The task of this node is to hang on to the current coming from the sinus node for a while. Why does the current need to be held on to? Because blood can only enter the ventricles while it is resting and by holding on to it, the contraction of the ventricles is disabled while the contraction of the atriums is taking place. By this process, the blood coming from the atrium can enter the ventricle. Therefore, the blood fills in the ventricles and can be distributed throughout the body. The blood circulation is enabled in a flawless manner by allowing the atriums to do their duty while the ventricles wait.

After passing through the atrio ventricular node, the electrical currency eventually goes through the purkinje fibers. These fibers surround the ventricles like a web and are composed of cells that can conduct electrical current in a very fast manner. Compared to the atrio ventricular node, the electrical current can be conducted 150 times faster in the purkinje fibers. Therefore, the current reaches every point of the ventricles in a very short period of time. Every muscle in the ventricles contracts in a time shorter than one tenth of a second.

The muscles in the ventricles rapidly contract, one by one, depending on when the current reaches them. The contraction starts at the end of the ventricles and carries on towards the main veins exiting the heart. By this orderly and harmonious contraction, the blood is pumped from the end of the heart towards the main veins exiting the heart to be distributed among the body. Because all the ventricle muscles are stimulated very fast, the contraction also happens very fast, resulting in a strong pumping effect. The design of this system is incredibly wise, right down to its most minute detail.

Movement in heart muscle potential

As all cells in our body, the cells in the heart also have a membrane potential. We had stated before that this membrane potential is the result of the difference in intra and extra cellular ion concentrations. The charges of these ions are different from each other. For example, sodium and potassium have plus one (+1) charges, calcium has a plus two (+2) charge, and chlorine has a negative one (-1) charge. The resting potential of a cell is negative. This means that there are more negative ions within the cell when compared to its environment. Sodium, calcium, and potassium ions are mobile through the membrane. While sodium and calcium have a higher concentration outside the cell, potassium has a higher intra cellular concentration compared to its environment. There are channels created on the cell membrane that allow ions to pass through the membrane. The sudden increase in the membrane potential that was explained before causes a sudden rush of sodium ions inside the cell. This is such a rapid movement that it is concluded in a tenth of a second. Right after the entrance of the sodium ions, calcium ions also enter. Because these ions are positively charged, the membrane potential becomes positive.

With the entering of calcium ions into the cell, calcium ions are also released from the storages within the cell. By triggering the protein necessary for these contractions, the calcium ions become a means for the contraction of the heart muscles. Meanwhile, the potassium channels open and these ions within the cell pass to the extra cellular environment. The loss of positive ions results in the membrane potential being negative again. Therefore, the sudden jump in membrane potential that is the basis for the electrical current is created.

However, at this point there are extra amounts sodium and calcium within the cell and extra amounts of potassium outside the cell. The concentrations need to be returned to their original values for the next jump in the membrane to be possible. This task is given to a protein called the sodium-potassium pump that pumps out sodium from the cell and pumps in potassium. If this pump had not been created, the ion balance in any of the cells within the body would be impossible to re-establish. As a result, the life of the cells would come to an end. However, because of the remarkable intricacy of our cells, life is made possible for us.

Afterwards, some amount of the calcium ions are pumped out of the cell with a similar pump, while the rest are stored within the cell. The decrease in the concentration of calcium relaxes the muscle. Now the heart muscle has gone into relaxation and therefore is ready for the next contraction.

If the movement of the ions becomes unbalanced, the rhythm of our heart is disturbed. The unbalance in the ion movements or blockage in heart veins can be reasons for heart rhythm disorders. Even small heredity-based defects in the ions pumps affect the movement of these ions and can cause heart rhythm disorders. This situation shows that nothing is created by coincidence.

Movement in the sinus node

The jump in the membrane potential of a heart cell depends on the membrane potential jump of the previous cell. Through the gaps in between the cells that are in contact with each other, the positive ions that exit a cell reach the membrane of the cell next to it and trigger the opening of its ion pumps. As a result, the membrane potential of that cell starts changing. At this point, you may have this question: how does the electrical current start in one end of the sinus node that is not previously triggered by any cell?

This concept is explained by the ion transfer mechanism of the node cells being different than the muscle cells. Before explaining this, it should be noted that even while resting, a mechanism for allowing an ion exchange of the cell with its surrounding has been created. In the node cells, this exchange while at rest has been created in a way that the sodium and calcium exchange is larger and the potassium exchange is lower compared to the muscle cells during resting conditions. Therefore, the membrane potential of the node cells is less negative and slowly increases with time. As a result of this slow but steady increase, after a while it reaches a threshold. When it reaches it, the calcium channels in the membrane suddenly open and there is a rush of calcium ions into the cell. Thus, the jump in the membrane potential is created independently from another cell.

As it can be observed, even a single contraction of our heart depends on a very detailed, delicate, and complex system. Moreover, this system is repeated over a hundred thousand times within one day. After reflecting on this, how can we claim this system runs by coincidence or chance?

Turkey is currently the sixth largest market for electricity in Europe and this demand for energy has made Turkey one of the fastest growing global markets for fuel. The expected energy demand for Turkey by 2020 is expected to be 570 GWh (giga watts per hour) (Demirbas 2005, 615). Today, Turkey pays approximately $50 billion a year to other countries for their high quality oil, gas and coal. If nothing is done to develop alternative sources of energy, it is expected that the cost to import fuel from other countries will cost Turkey a staggering $100 billion in 2020. Fortunately, in 2005, Turkey passed a Renewable Energy Law to bring the country more in line with European Union regulations and standards to meet the growing electricity demand and to diversify sources of energy.

Wind power

Turkey could potentially meet all its total energy needs solely from the use of wind energy. The most attractive sites for wind energy utilization and generation are the Marmara, South East Anatolian and Aegean regions. The first wind energy farm was established in Izmir, Turkey in February 1998 with a 1.5 MW capacity (Hepbasli and Ozgener, 2004). On the other hand, the U.S. started harvesting wind power 17 years before Turkey. We need to keep in mind that the U.S. is on a grand scale when compared to Turkey. It is interesting to see the trends for the usage of wind energy between these two countries. The current electricity production from wind for Turkey is about 433 MW (Megawatts) as compared to 35,000 MW for U.S. While Turkey is targeting to achieve a quarter of its potential, 20,000 MW by 2020, the U.S. is intending to reach 90% of its potential and reach 10×108 MW (Table 1) by 2020.

Table 1: Wind power: Turkey and U.S.

Solar power

In terms of the potential of solar power, both Turkey and the U.S. are amongst the most propitious countries in the world by having a range of 175- 200 watts per square meter per day (David Wheeler, Global Developments for Future Blog, comment posted on February 19, 2008).

The most advantageous region in Turkey for the harvesting of solar energy is its Southwest due to its geographic location in the Mediterranean. It is quite common to come across solar panels on top of the roofs in Southwestern Turkey. Photovoltaic (PV) systems are currently limited in use in Turkey but they are on the rise. In Silifke, located south central Anatolia (about 200 km away from Adana), a PV system is currently being used to power irrigation pumps. In order to encourage investors to invest their money into the development of solar power in Turkey the government subsidies need be increased and include the current 5.5 euro-cents/KWh feed-in-tariff.

The most common places where you would see heavy solar power usage for everything from day and night lighting to heating the pool in Turkey are in Eco-homes (left), and Solar cities (right).

Source: http://www.qurbaa.com/images/eko-evleri.jpg

Source: www.solartek.com.tr/tr/index.asp?ID=34

*The hot water heating system installations cover about 10 Million m2 surface.

What is interesting to note is that currently Turkey is amongst the top five countries in the world in the amount of solar power used to heat their water.

Hydropower

According to the Idaho National Laboratory, approximately 6,000 MWs is the gross power potential of U.S. hydropower, of which only about 16 percent can be developed with economical feasibility. About 76 percent of this potential has already been developed, and the remaining portion is to be developed by 2020. On the other hand, Turkey has a somewhat different scenario where the gross hydropower potential is 435 MW, of which only 29% is economical feasible for development and only 35% of that potential has been developed to this date (Yuksek et al. 2007).

After Turkey declared its support for the Kyoto Protocol, it has given a big push for renewable sources of energy, especially wind and hydropower. With the required regulations passed after Kyoto, and with the more recent Copenhagen Accord, Turkey has adapted rigorous development plans for its hydropower potential. The total number of current hydropower projects is over 350, and it is estimated that Turkey can meet up to 46% of the energy demand in 2020 from hydropower resources (Yuksek et al. 2007).

Lifestyles

One of the most important issues for environmental consciousness is energy efficiency. Saving energy is a way of life, not just a part of it.

The automobile has become an integral part of American life with vehicles outnumbering licensed drivers: 254 million cars and 194 million licensed drives. In Turkey the latest statistics showed that there are only 23 million licensed drivers as compared to the 16 million cars on the road. These statistics proves that people living in Turkey tend to more commonly use alternative means of travel, such as the public transportation system, rather than driving their own cars, especially in the larger cities such as Istanbul, Ankara, Izmir, Konya and Bursa. In Istanbul there are even designated lanes along the highway for buses. Although buses, subway, and streetcars are among the preferred ways of transportation since their network pretty much covers everywhere, however, the big cities are still experiencing heavy traffic on the streets due to passenger cars.

The good news is that in Turkey the vast majority of the fleet of taxis and buses have been converted to Liquefied Natural Gas (LNG) form, saving energy and money.

Environment awareness amongst the populace is also on the rise as well. Having young minds working on the cultural practices that need to be changed for a sustainable future requires both courage and time. To this end, Turkey has devoted the week of January 11th to raise the awareness for energy efficiency. Turkish schools celebrate this week by educating students from all ages in terms of matters governing energy and efficiency.

Rain water catchment systems, have always been part of the architectural design for buildings, however, the water collected from the roof was basically drained down to the garden and was not very practical. With the young generation raising awareness to not waste this precious resource, people have created better designs to capture and find a better use for the rain water.

Rain gutter designs are quite different in Turkey in comparison to the U.S. as well; instead of having them on the side of the curbs, they are designed as screens along the streets. Some cities have canals that bring melted snow and rain water to the middle of the city from the mountains in the vicinity. This water is then used for irrigation purposes.

According to the 2004 statistical figures of the Turkish Statistical Institute (TURKSTAT) 34 million tons of municipal waste and 17.5 million tons of industrial waste are produced in Turkey annually. The amount of wastes produced per person in Turkey reaches up to 1 kg (2.2 lbs) daily, of which 34% is food waste. This figure is very small in comparison to waste generation in the United States. The average waste generation in the U.S. is 3.5 kg (7 lbs) per person per day. It is believed that the cultural habits and practices of a people can affect the energy efficiency and minimize waste generation in their country. The practices in Turkey include but are not limited to using the produce when it is abundant and preserving it for later use either by drying fruits and vegetables, creating pastes (such as tomato paste), making marmalade and jams, as well as canning fruits and vegetables and pickling vegetables.

When it comes to our garbage, waste prevention – rather than waste management – is the best way to reduce environmental stress (Brown 2008, 7). It might come as a shock to some, but the most common drink in Turkey, black tea, is still today served in reusable glass cups (below). This differs in the U.S. where 16 billion paper cups are used for coffee on average in 2006, resulting in 253 million pounds of waste (Hillary Feldman, About My Planet Blog, comment posted on May 29, 2008). We need to adapt to thinking in terms of “Waste equals food” as Paul Bierman-Lytle, an architect working for the American engineering firm CH2M Hill, described the concept that waste from one system should provide food for another, whether an industrial system or an ecosystem.

Having said all the above, some of the highlights from Turkey’s future plans include the following: accelerating expansion in renewable sources of energy, aligning Turkey with the European Union regarding renewable sources of energy, using the Multilateral Clean Tech Fund – according to the World Bank, Turkey is the first to receive that fund in 2009 – reduce greenhouse gas emissions, subsidize investors and investments in renewable energy resources, reduce waste generation and improve waste recovery with the help of research and development on these issues.

As humans, although we might see ourselves losing the battle of “Saving the Earth” today, however, we still have the chance to turn things around before it is too late.

I believe if we all work hand in hand to raise global citizens, who can understand and value common humanity, we can get us to work together toward a sustainable future.

Fethiye Ozis is a Lecturer, Civil and Environmental Engineering Department at University of Southern California.

References

• – About My Planet Blog, http://www.aboutmyplanet.com/environment/paper-unsustainable/
• – Brown, Lester R. Plan B 3.0: Mobilizing to Save Civilization, W.W. Norton & Company
• – Center for Global Development Blog, http://blogs.cgdev.org/globaldevelopment
• – Demirbas, A. “Competition Potential of Wind Power Plants” Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, Volume 27, Issue 7 May 2005, p 605 – 612.
• – DIE (State Statistics Institute). Statistics of Turkey in 2003. 2004. DIE. Turkey.
• – Hepbasli, A.; Ozgener, O. “A review on the development of wind energy in Turkey” Renewable and Sustainable Energy Reviews, Volume 8, Issue 3, June 2004, p 257-276.
• – Omer Yuksek, Murat Kankal, Murat Ihsan Komurcu, Hizir Onsoy, and Adem Akpinar. 2007. The Importance of Hydropower plants in Turkey’s Energy Planning.Paper presented at the international Congress on River Basin Management, March 22-24, in Antalya, Turkey
• – Turk Medya Adana, CNN Turk http://www.turkmedya.com/V1/Pg/detail/NewID/131268/CatID/6/CityName/Adana/ TownID/2/Header/gunes_enerjisi_tarimda_kullanildi.html

Let us imagine the earth as a small sphere before us. If we throw an object from the North Pole toward point A on the equator line, the object follows a curved line towards the right side and reaches point B, not point A. Likewise, an object thrown from the South Pole towards the same point A will follow a similar line curved in the opposite direction. These cases have a common point. An object rolling on a rotating ground moves on a curved line. This curved line, instead of a straight one, is explained with reference to the force of acceleration. This force is named after the French engineer, Coriolis who explained it in 1835. If this force-which is generated by the earth rotating around its own axis-did not exist, then air movements and ocean currents, and consequently the climate conditions of our world, would be different than they are. The objects in our example, thrown from the two poles, go in different directions, because the world rotates counter-clockwise when looked from the North Pole, and clockwise from the South Pole.

The air over the equator receives the sun’s rays at a broad angle. It rises up after gaining heat and is replaced by colder air coming from distant latitudes. Air convection begins in connection with these heat changes. So if the world did not rotate, the air on the Poles would get heavier with cold air and come down. Then, it would be replaced by hot air from lower latitudes. The air at the equator would rise up with gaining heat and would move until reaching the Poles where it would come down after losing heat. Then, it would return to the equator, this time very close to the ground. In this case, the world would probably be an uninhabitable place with cold and fierce winds blowing all around. And of course, the side facing the sun would be very hot and the other side would be very cold.

Instead, the Coriolis effect makes these great atmospheric air masses move over our rotating earth. The hot air rising up from the equator moves towards the poles with a curved course thanks to the Coriolis effect (Figure 4). As this air current approaches the latitudes around 30 degrees, it loses heat and descends. A part of the descending air begins to move back toward the equator, but it follows a curved line again owing to the Coriolis effect. So this last curving forms the “trade winds.” In the past, sailing ships traveled from Europe to America for the purpose of trade; thus, these winds were named as trade winds. This air circulation between the equator and the 30-degree meridians is known as Hadley circulation. These air currents cause heavy rainfall in the equatorial region and the consequent formation of rain forests, which are considered as the lungs of our planet, and also they cause the formation of deserts around the region where the dry and hot weather are pure blessings for us. They are a blessing because the airborne dust rising from the desert fertilizes the rainclouds and plays a critical role for rainfall.

The air over the poles becomes cold, and it causes another air current as it becomes heavier and starts to descend. As the lowered air moves toward the equator, it changes course with the Coriolis effect. At the same time it begins to gain heat and ascend. At the latitudes where water ascends by gaining heat, a rain climate prevails. This polar air cycle is seen between latitudes of 60-90 degrees.

Some part of the air current, which descends down around 30 degrees of latitude, moves toward the poles at a low level. Also, some part of the air which comes from the poles and ascends begins to move towards the equator. So a third air cycling begins between the altitudes between 30-60 degrees. The “western winds” are brought forth from this third cycle. During the time of sailing ships, these winds were used to traveling from America to Europe (Figure 4).

In order for these air cycles to happen, the earth’s rotation around its own axis is not sufficient; its speed and atmospheric mass also play an important role. If the earth rotated slower, the Coriolis Effect would be too weak to give way to a triple air cycle. For example, since Venus rotates too slowly, there is only a single air cycle in its atmosphere. Another factor, as we mentioned, is the mass of the atmosphere. Since the atmosphere of Mars is thin and its mass is relatively less, the Coriolis Effect is too weak and there is only a single air cycle.

Coriolis Effect prevents the air current from following a straight course and the isobars form twisters as they proceed. Therefore, hurricanes in the Northern hemisphere move counter-clockwise, and those in the south move clockwise (Figure 5). Naturally, these main atmospheric movements are not the only ones. A region’s climate is dependent on several factors such as landscape, night-day heat differences, and the like. Therefore, the climatic conditions on the earth have a very complex structure. Even when we consider just these few factors discussed here, it is evident that there are countless parameters that make human life possible in our planet, and each one is finely adjusted. Even slight changes in rotation and the mass of the atmosphere would result in a dramatically different planet Earth.

The ocean currents

Movement of air masses affects the water on the ocean surface as well. Thus, wind-generated surface currents are born. These currents are parallel with the relevant winds. It is a well-known fact that these huge bodies of water change the climate of the regions they pass. Therefore, two places at 54 degrees of latitude show a surprising difference: there can be a polar bears’ park in Ontario, whereas palm trees and tropical fruits can grow in Belfast thanks to the Gulf Stream. There are other warm ocean currents that pass from Brazil, and the north and south of the equator. Some of major cold surface currents pass from Labrador, Canada, the Falkland Islands, and Peru. Warm currents soften the climate of the regions they pass, while cold currents provide sea creatures with rich food, and they are important areas of fishing.

The impact of the wind on ocean water normally reaches as deep as 100-200 meters, and even 1,000 meters in some cases. The Coriolis effect has a determining role on the direction of the currents. These currents on the move make a turn when their way is blocked by land. Thus, the succession of ocean currents becomes a cycle, and they form the great current cycles named as “gyre.” They turn clockwise in the Northern Hemisphere and counter-clockwise in the south.

There are five main ocean circulations on earth and each of them consists of four streams. These currents are at the north and south of the Atlantic Ocean, the north and south of the Pacific Ocean, and one in the Indian Ocean. The North Atlantic circulation is made up of the Northern Equator Current, the Gulf Stream, North Atlantic Current, and the Canary Current.

With the Coriolis effect, a blessing of wondrous scale, food chains are brought to life in the ocean and around coastal regions. The ocean waters are set in motion by the winds generated by the Coriolis effect, but they do not strictly follow the winds that activated them. With a deflection of nearly 45 degrees they move right in the Northern Hemisphere and to left in the Southern Hemisphere.

The effect of the winds weakens in the deeper ocean waters, and then the Coriolis effect becomes dominant. Thus the direction of ocean water carried in the Northern Hemisphere is vertical to the wind direction and towards the right. This condition causes ocean waters to be pushed towards the circulatory center, and the water level there rises about 2 meters.

As rising waters move down with the effect of gravity, the Coriolis effect comes to the stage again to give way to another current in the same direction within that current. The waters that were rising toward the center begin to sink, and they form a new vertical current. For the same reason, the separation of the water current to the right and left directions around the equatorial regions gives way to the waters at the bottom which then come to the surface. At these places, the water level decreases a little. This “upwelling” phenomenon has very important results. Dead organisms sinking down are broken down by bacteria in the deep waters. When this nutrient-rich water returns to the surface, it is a great blessing for so many sea creatures. It is a striking fact that the rotating of the earth is a means for providing many living beings with sustenance. All of these finely adjusted balances on our planet, which we mostly take for granted, provide reflecting minds with food for thought.

Conventional water and wind turbines cannot function properly in a whirling current; the working of turbines depends on the existence of a steady and regular flow. In order to be able to obtain energy from vortices, turbines would need to mimic the movements of fish, adjusting their position to the differing angles of flow. A mechanical device to be developed in this respect should perceive the angle of the current flow instantly and adjust itself accordingly.

Normally, wind turbines are set up in high and open places. However, in cities the eddies that are formed by winds moving around buildings and roofs prevent conventional turbines from working efficiently. In order to overcome this challenge, scientists are aiming to develop turbines that benefit from the dynamic principles apparent in the movement of fish, though without imitating the fish exactly. They hope that in this way it will be possible to produce energy from turbulent currents as well. The projects being devised aim to develop different types of turbines to work in air and water. The energy production of these turbines will naturally be relatively low in comparison to common wind turbines operating in strong winds. However, these new types will make it possible to produce energy from winds moving at less than 32 feet per hour, when conventional turbines do not function. So, the total annual energy they are expected to produce will be no less than the regular wind turbines. If scientists can successfully model the admirable engineering applied in the bodies of fish, they will be able to boost the efficiency of these devices dramatically.

Notes

1. For further information see Liao J. C. et al., “Fish exploiting vortices decrease muscle activity,” Science 302, 1566–1569, 2003.
2. Dabiri, J. O., “Renewable fluid dynamic energy derived from aquatic animal location,” Bioinspiration and Biomimetics 2, L1-L3, 2007.

Enron in only the poster boy for the type of greed running rampant in today’s multinational corporate world. Despite the rhetoric spilling over the airwaves of the world media, the truth cannot stay hidden for very long in this age of information. The world’s current level of violence is tied directly to the greed of such corporations and so-called leaders who care nothing for the people’s general welfare. They have sold their souls, as the cliché goes, joined hands with Satan, and are ready to ride off into the sunset.

I am not referring to any particular country, people or hemisphere. The greed that we see today exists among all races, religions, and nations. Granted, some may be guiltier than others, especially in light of current world events, but the evil force of greed does not discriminate. Satan has used greed to dupe many people, even Muslims. As Abdullah Yusuf Ali comments in his Qur’anic translation: What an evil choice he makes in committing treason against his own Benefactor (Allah) by going after the petty baubles of this world’s wealth of fleeting gains. How eloquent and true. Greed is nothing but selling our fate in the akhirah (the Hereafter) for this world’s temporary cheap thrills “ often at a tremendous expense to others.

Some facts you should know

So just how bad has it gotten? To what degree has greed enveloped the entire world? The following provides a shocking glimpse:

– In a statement by the Institute for Policy Studies, the group said that 497 billionaires registered a whopping collective wealth of 1.54 trillion dollars. This is way above the combined gross national products of all the nations of sub-Saharan Africa, which stands at only 929.3 billion dollars, or those of the oil-rich regions of the Middle East and North Africa 1.34 trillion dollars.1

– This collective wealth of the 497 is also greater than the combined incomes of the poorest half of humanity, says IPS.2

– Last week, the U.S. government announced that it was building the biggest-ever war machine. Military spending will rise to $379 billion, of which $50 billion will pay for its ˜war on terrorism.’3

– The wealth of the Forbes 400 richest Americans grew an average $1.44 billion each from 1997-2000, for an average daily increase in wealth of $1,920,000 per person ($240,000 per hour, or 46,602 times the U.S. minimum wage).4

– Funds in the hands of U.S. money managers grew from $1.9 trillion in 1980 to $17 trillion in 2000. While those funds were under the control of fiduciaries (half the funds are due to tax incentives), the pay gap between top executives and production workers in the 362 largest U.S. companies soared from 42:1 in 1980 to 475:1 in 1999.5

– The financial wealth of the top one percent of U.S. households now exceeds the combined household financial wealth of the bottom 95 percent.6

– The top fifth of U.S. households claims 49.2 percent of national income while the bottom fifth gets by on 3.6 percent.7

Of course, these all refer to the U.S. However, the U.S. and the western world are not alone in being the culprits of such distorted wealth distribution and inequality. For example,

– In Indonesia, 61.7 percent of the stock market’s value is held by that nation’s fifteen richest families. The comparable figure for the Philippines is 55.1 percent and 55.3 percent for Thailand.8

The impact of such greed is devastating for the rest of the world. Consider these facts:9

– Eighty countries have per capita incomes lower than a decade ago. Sixty countries have grown steadily poorer since 1980.

– In 1960, the income gap between the fifth of the world’s people living in the richest countries and the fifth in the poorest countries was 30:1. By 1990, the gap had widened to 60:1. By 1998, it had surged to 74:1.

– From 1995 to 1999, the world’s 200 wealthiest people doubled their net worth to $1,000 billion.

– Three billion people presently live on $2 or less per day, while 1.3 billion of those get by on $1 or less per day. With the global population expanding by 80 million each year, World Bank President James D. Wolfensohn cautions that unless we address the challenge of inclusion, 30 years hence we may have 5 billion people living on $2 or less per day.

– Two billion people suffer from malnutrition, including 55 million in industrial countries. Thus, in 3 decades, neoliberal-style globalization could create a world where 3.7 billion people suffer from malnutrition.

– The UNDP’s assessment: Development that perpetuates today’s inequalities is neither sustainable nor worth sustaining.

Although the above facts offer just a glimpse of the big picture, it is quite clear that the current policies of nations and their corporate entities are destructive, oppressive, and barriers to peace and justice. Such policies are making a select few rich beyond comprehension while the vast majority either barely survives or literally starves. This is our world’s hard and cold reality “ a reality that goes largely unchecked even among the educated masses of the developed world. Unfortunately, those same educated masses seem content to be brainwashed by a corporate-controlled media that tells them next to nothing about the world’s true condition. According to those who control information, people are on a need-to-know basis, and most of what is truly important the people simply do not need to know!

A worldwide epidemic

This is truly a worldwide epidemic, for it can be found in the third world as much as (if not more than) the developed world. It is a problem, however, that can be addressed only at its roots. While living in both the U.S. and Southeast Asia, I have learned that these problems all stem from the same place. The appearances (e.g., people, cultures, and religions) may be different, but ultimately everything that ails us has the same root causes, as mentioned in the Qur’an. Greed is greed, whether it is that of Enron or some other corrupt entity somewhere else. It may look different and the people may speak a different language, but the ailment is the same, because underlying it all are the same diseases of the heart. This is precisely why the Qur’an is for humanity “ because we have so many fundamentals in common with our fellow human beings.

All of us are capable of harboring some of these booby traps of the soul (e.g., greed, injustice, envy, and hatred). This is why we cannot point fingers at one nation, person, or corporation. The diseases of the heart are killers, and they are killing, starving, and oppressing millions of innocent people. Thus we have to deal with the sickness’ cause, not just its symptoms. More war and destruction may eliminate some of the culprits, but it certainly will not rid the world of the problem, which is, ultimately, sickened human hearts feeding on ignorance.

Globalization

We must be wise at such times and seek out wisdom, not just information as to how the world works. Globalization, which is actually just a fancy innocuous-sounding term for the westernization and materialization of the entire planet, is not in most people’s best interests. In fact, some less well-known world leaders have been brave enough to acknowledge this. Malaysian prime minister Dr. Mahathir Mohamed has consistently spoken out against the dangers of globalization in its current guise. He considers it to be nothing more than the developed nations leveraging its huge capital advantages in order to exploit developing and underdeveloped nations.

By lining the pockets of weak, corrupt government leaders, multinational corporations are free to wreak havoc on the people, economies, and lands of weaker nations. Dr. Mahathir has said that capital must be equalized first if the current form of globalization is to have a truly equalizing effect on all nations’ economies. Developing countries must be protected and their own economies nurtured until they can compete on an even playing field. However, this is far from the case today. Thus, globalization in its current form allows developed nations to strip developing nations of their resources while spreading a culture of consumerism and materialism through their huge multinational corporate media and advertising machines.

A Qur’anic perspective

To further understand greed from a Qur’anic perspective, we should understand why God banned usury: Those who devour usury will not stand, except as stands one whom the Evil One has driven to madness by his touch (2:275). When referring to this verse in his Tafsir al-Qur’an, Daryabi says: According to the socialist writers of today, money is lent by them who have abundance and returns to them to increase that abundance, the increase being the unpaid dues of labor, which is the only source of wealth “ the rich are thus made richer and the poor poorer, by every fresh act of taking interest, and the stability of social organism is disturbed. This analysis is perfectly consistent with the world economy today. Look around “ interest is everywhere, wealth is in the hands of a few, and the gap between rich and poor is growing ever wider. The result? The social organism is grossly disturbed.

This is why the Book is called Al-Qur’an al-Hakim (the wise Qur’an). It is a book full of wisdom. The evils of usury, greed, and their ugly companions are forces that have destroyed entire peoples throughout history. They are problems that humanity cannot shake, especially when we turn away from the Creator’s wisdom and guidance.

Our world’s current course, with the haves and the have nots growing apart at an exponential rate, cannot be sustained. Somewhere, somehow, and at some point there will be a monumental adjustment. A world economic system that is so unequal, so unjust, and so divisive cannot last for long. The powers-that-be currently controlling the world economy are deluded if they think that they can continue their corrupt policies while 95 percent of the world sits back and does nothing. Sooner or later, it will come to a crashing halt.

Islam provides a straightforward solution to this problem. Yet history has proven that until humanity can tackle the evil that lies within each person, we will never address the evils around us effectively. The solution is called fairness (justice) and cooperation. In our present capitalist-dominated world, such terms seem utopian. Unbridled competition is the name of the game and, moreover, there is no indication that this will change any time soon. Such over-competitiveness seeps into every aspect of life until entire societies distrust one another, become antisocial, and are completely dysfunctional from a social perspective. This is already the case in much of the western world.

Conclusion

Islam encourages people to come together, rely on one another, and commune. It already has the built-in, well-formulated systems to do it in an inclusive way one that is neither elitist nor harsh. Islam says that when people unite to build and do good works out of a desire to achieve goodness for all and His approval, they will earn His pleasure. When humanity is granted God’s succor, the sky is the limit in terms of what can be accomplished. The glorious history of Islamic civilization proves this.

This is how the Prophet erected the perfect society in seventh-century Madinah. In that society, people worked, lived, and worshipped together. Muslims, non-Muslims, and different peoples and tribes co-existed peacefully, all agreeing to live under one leader in a perfectly just system. That leader was a man who desired nothing for himself and only the best for his fellow believers and neighbors. Until those with envy and hatred in their hearts spoiled the peace, Madinah showed the world how belief in God, cooperation, and living for the common good are the keys to peaceful coexistence. This can never happen again until humanity is willing and able to fight the sicknesses lying deep within each person’s heart.

Footnotes

1. Steve Smith, World Billionaires Still Richer than Half of Humanity. Online at Islamonline.net, 2002.
2. Ibid., 2002
3. John Pilger, The Colder War, The Mirror 20 (30 January 2002).
4. Online at www.forbes.com.
5. Business Week (7 April 2000), 100.
6. Edward N. Wolff, Recent Trends in Wealth Ownership (paper for the Benefits and Mechanisms for Spreading Asset Ownership in the United States conference, New York University, December 10-12, 1998.)
7. Online at www.census.gov [Table H-2].
8. Stijn Claessens, Simeon Djankov, and Larry H. P. Lang, Who Controls East Asian Corporations? (Washington, DC: The World Bank, 1999).
9. Jeff Gates, Modern Fashion or Global Fascism, Tikkun: A Bi-Monthly Jewish Critique of Politics, Culture, and Society (Jan.-Feb. 2002).

The Process of Discovery

Kamerlingh Omnes, a Dutch physicist dedicated to achieving ultracold refrigeration, opened this field in 1908 by liquefying helium at -452 F (4 K or -269 C).(1) This achievement enabled scientists to cool materials to very low temperatures and study their properties.

Scientists knew that a metal’s resistance fell as the temperature was lowered, but did not know what the limiting value would be when 0 K (the absolute minimum temperature) was approached. In 1911, Omnes began investigating the electrical properties of metals at very low temperatures. Many contemporaries, including Lord Kelvin, believed that resistance eventually would level off to a nonzero value. While passing a current through a very pure mercury wire whose temperature was being steadily lowered, Omnes noticed that its resistance vanished at 4.2K. He remarked: “Mercury passed into a new state, which on account of its extraordinary electrical properties may be called the superconducting state.” This marks the birth of superconductivity.

Scientific and commercial potentials were obvious. A resistance-free metal wire could carry current for a long time without any loss. Omnes tried to determine the amount of such a loss. After letting a superconducting loop run for a year, he determined that there was no significant current loss. He was awarded the Nobel Prize in 1913 for his discovery.

In 1933, Walter Meissner and Robert Ochsenfeld discovered that superconductors are both perfect conductors and perfect diamagnets, for magnetic fields cannot penetrate a superconductor’s interior. When a material is superconducting and a field is applied, the current flowing on the superconductor’s surface generates a magnetic field that cancels the applied field inside the superconductor (the Meissner effect). Since the magnetic field generated inside the superconductor opposes the applied field, superconductors are diamagnetic. This shielding of an applied magnetic field occurs only if the applied field is not very large. Superconductivity is destroyed at a certain point.

Theoretical Progress and Surprises

Theoretical progress was much slower, however, almost as if superconductivity had been discovered too early. The scientific community’s incomplete understanding of quantum mechanics made it impossible to understand the mechanism behind superconductivity. Some phenomenological theories were developed during the 1930s and 1940s, but a clearer picture only began to emerge in 1957.

Three American physicists, John Bardeen, Leon Cooper, and Robert Schriffer, used quantum field theory and many-body physics to develop the BCS theory, which explains superconductivity for elements and some alloys.(2) In essence, the theory states that a superconductor’s electrons condense into a quantum ground state and move together coherently. Pairs of electrons (Cooper pairs)-not single electrons-achieve current transfer. These physicists received the Noble Prize in 1972.

Another milestone came in 1962. Brian Josephson, a Cambridge University graduate student, predicted that an electrical current could flow between two superconductors separated by thin insulating barrier. He made a suitable device (the Josephson Junction) by inserting an insulating material between two superconductors. Sending current through one superconductor, he saw it pass through to the other one. Known as the Josephson effect, it is one of the most important components in superconducting electronics. Josephson was awarded a share of the Nobel Prize in 1973.

In 1986, Alex Miiller and Georg Bednorz of IBM Research Lab (Switzerland) synthesized a ceramic compound that superconducted at 30K (-243C), the highest superconductor temperature ever reached. This compound contained lanthanum, barium, copper, and oxygen. Scientists do not know why it super-conducts, for it insulates at high temperatures and conducts electricity very poorly before it superconducts. Bednorz and Miiller received the Noble Prize in 1987.

This discovery inspired many researchers to combine elements to achieve superconductivity at higher temperatures. In January 1987, researchers at the University of Alabama replaced the lanthanum in the Bednorz-Miiller compound with yttrium and reached a transition temperature (Tc) of 92K. As a result, the much cheaper liquid nitrogen could replace liquid helium as a coolant. By trial-and-error experimentation, a Tc of 138K was reached in a compound consisting of mercury, thallium, barium, calcium, copper, and oxygen.

These new materials all contain layered copper and oxygen planes with other elements in between the crystal structure. Superconductivity occurs on the planes, and the rest of the crystal serves as a charge reservoir. The magnetic field gradually penetrates these new materials (called High Tc superconductors), causing a mixed state between the normal state and the superconducting state.

In 1997, existing theories were shattered when an alloy of gold and indium was used as a superconductor and a magnet. This is expected to have an important effect on magnetic data storage.

The most recent surprise came in November 2000. About 10 years ago, scientists learned that carbon-60 could superconduct at near absolute zero. By expanding the lattice structure, a Tc of 52K was reached. About a month later, the same group reached a Tc of 90K. Many believe that this temperature could reach well over 100K. Carbon-60 is the only material that has reached such high Tcs without having copper and oxygen planes in its structure.

Applications

Superconductors do more than just conduct electricity. Other important functions are as follows:

• The Korean-developed SQUID (Superconducting QUantum Interference Device) can detect magnetic field changes that are 100 billion times smaller than Earth’s minute magnetic field, and uses the most fundamental properties of superconductors and quantum mechanics. Medical researchers use SQUIDs to study the human brain. Systems in which hundreds of SQUIDs are arranged in a helmet-like configuration containing liquid helium are commercially available. These systems detect the magnetic field produced by thousands of neurons. Although neurons produce huge fields when compared to the SQUID’s sensitivity, a magnetically shielded room is required to filter out fields produced by TVs, computers, cars, and so on. In these rooms, external stimulation applied to the patient’s brain enables specialists to locate tumors or other ill-functioning areas by mapping the brain’s functions. The human brain has two types of responses: stimulated and self-generated (spontaneous). By using the SQUID’s fast temporal response, one can locate non-invasively the epileptic loci, which causes some diseases. Alzheimer’s and Parkinson’s research also use SQUIDs at the detection level.

• Magnetic levitation became possible after scientists built superconducting magnets. Since superconductors have no resistance, a small voltage can generate huge currents and, therefore, magnetic fields large enough to float vehicles on these superconducting magnets with almost no friction. In 1999, a train in Japan reached a speed of 343 miles per hour. Japanese researchers are studying the possibility of a mag-lev linear motor car.

• Superconducting magnets have been used extensively in particle accelerators since 1987. Particle physics requires the acceleration of subatomic particles to speeds very close to the speed of light. This necessitates high magnetic fields that, in turn, need high currents-something for which superconductors are ideal. One event that made superconducting better known is probably the American Congress’ cancellation of the multi-billion Superconducting Super Collider (SSC) project in 1993. A European consortium is now pursuing this research field.

•Superconducting wires improve an electric generator’s efficiency by more than 99 percent. In addition, such generators are about half the size of conventional ones. General Electric estimates that there is a potential $20-30 billion global market for superconducting generators. Unfortunately, the high costs of cooling systems rules out using this technology to supply cities with electricity. But the moment sufficiently high Tcs are reached, superconductivity’s impact in this area will be immeasurable.

•Other applications are high-performance and high-capacity electronic filters (currently used in some cellular phone systems); a petaflop-computer (1,000 trillion floating point operations per second-1,000 times faster than today’s computers); mine and submarine detection (the U.S. Navy); and storing energy to enhance power stability (American Superconductor Corp.); satellites; telescopes and other light detection instruments; and Internet routers.

Footnotes

1. F (Fahrenheit): A temperature scale registering water’s freezing point as 32F and boiling point as 212 F at one atmosphere of pressure. K (Kelvin): A unit of absolute temperature equal to 1/273.16 of the absolute temperature of the water’s triple point; equal to one Celsius degree. C (Celsius): A temperature scale registering water’s freezing point as 0 C and boiling point as 100 C under normal atmospheric pressure.
2. Quantum field theory: A body of physical principles that accounts for subatomic phenomena. Quantum many-body physics: The branch of theoretical physics that studies the new collective phenomena or “elementary” constituents of a many-particle system and the underlying quantum mechanics that determines their behavior.

References 

• Clarke, J. “Superconductivity: A Macroscopic Quantum Phenomenon.” Beam Line 30, no. 2 (summer/fall 2000): 41-48.
• Dull, R. W. and H. R. Kerchner. “Applications of Superconductors.” A Teacher’s Guide to Superconductivity for High School Students (1994). Online at:
• www.ornl.gov/reports/m/ornlm3063r1/pt4.html.
• Gunnarsson, O. “C60: The Hole Story.” Nature 1408 (30 Nov. 2000): 528-29.
• http ://superconductors .org
• Tinkham, M. Introduction to Superconductivity. 2d ed. McGraw-Hill Higher Education: 1995.

WHY OPTICAL?

Despite the many benefits that classical computers (‘classical’ here means computers in which the signals are carried electrically) have brought to our lives, they have some limitations which prevent any improvement in the speed or volume of signals carried. These limitations are inherent to the way these computers work.

For example, classic electric circuits carry information units serially, one by one, and there are some lower limits beyond which such circuits cannot be built-below that limit they simply cannot process the information reliably. Another handicap is that electrons floating in circuits can interfere with each other-and this interference, incidentally, is one reason why engineers cannot produce smaller circuits. By contrast, photons, light particles, which are the main signal or information carrying agent simply do not interact with each other because they do not carry a charge.

An optical computer could be run faster than one running electrons, theoretically at the speed of light, along optical fibres which are specifically designed guide-wires to transfer light-photons in and out between chips in an optical computer without distortion.

One of the main advantages of optical computers is their capability of processing more than one piece of information at the same moment. That means multi-beams can be processed in one chip. This would allow engineers to use parallel processing which greatly enhances the speed of the computer.

THE DIFFICULTIES

Lasers would, naturally, be the source of light in this new generation of computers. Scientists and engineers all over the world are trying to build appropriately tiny lasers emitting precise frequencies of infrared light. But they face a number of practical hurdles. One has to do with making lasers of appropriate size and efficiency. Current technology does not have the means to build optical chips comparable in size to ‘classical’ ones. The efficiency of the lasers is not high enough for the specifications required. Most of the energy to run these lasers escapes as heat and is not used. Since one or at most two percent of this energy can be transformed into the useful form of light, the rest can generate a lot of heat which is dangerous to the condition of the chips.

Making the right lasers is not the only problem on the way to fully optical computers. Switches are at the heart of optical computers, but as photons do not interact with each other, there are substaintial difficulties in building switches.

SOME PROPOSED SOLUTIONS

One solution to this problem is to build computers which are part electrical, part optical. Many scientists now believe that the most viable use for optical technology is in this type of hybrid system combining optics and electronics. Researchers are now focusing their work on optical interconnections between chips, which could be a reality in as little as one or two years. This type of connection can vastly increase the amount of data moving in and out of chips.

Such a machine would have to contain prisms, mirrors, and lasers to channel the light, as well as gallium arsenide chips that convert pulses of laser light into electrons so as to function as switches. If all this does happen, there will be a need for new computer architectures, that is, new computer structures.

However, there are some scientists following a different route. They are trying to find ways to use current transistor technology so as to detect laser beams in the information processing. NPN type transistors without a metal cover would be appropriate because they are faster. This approach also allows for adaptation of existing designs, with all the advantages in time and savings that brings.

FUTURE

The first optical processor developed at AT&T Bell Labs measured about two feet by two feet. Scientists hope some day to fit it all into three square inches. A fully optical computer is more than five years away.

Scientists have set themselves a target for the year 2000: 1,000 I/O (input and output) channels running at 1 giga-bit/sec. That is a thousand times faster than current modern computers.

It is a pity that we must wait for a decade, while scientists and engineers try to accomplish this difficult task. But what an exciting wait!

•  FURTHER READING
• ‘Bright future’, Scientific American, May 1990.
• ‘Now easier optical’, Electronics, May 1990.
• ‘Slacken lights up’, Scientific American, July 1991.
• ‘Optical computer no longer lighters away’, Byte, April 1992.
• ‘Optical computing sheds ‘blue sky’ image’ Electronics, April 1990.