The Founder of the Most Important Equation of All Time, James Clerk Maxwell

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Figure 1. James Clerk Maxwell (1831-1879)

Despite having a very significant influence in bridging the classical era into the modern era and is called one of the most influential physicists ever to exist with Isaac Newton and Albert Einstein, few people are familiar with James Clerk Maxwell commonly known as Maxwell. His greatness made Maxwell the foundation for Mr. Relativity, Albert Einstein, in developing his modern ideas expressed in the following sentence: ” I stand not on the shoulders of Newton, but on the shoulders of James Clerk Maxwell “.

Born on June 13, 1831 in Edinburgh, Scotland, since childhood Clerk Maxwell already has a great sense of curiosity about how something can happen and work. This curiosity led Maxwell’s 14-year-old to complete his first paper on oval geometry entitled On the Description of Oval Curves, and Those Having a Plurality of Foci read by the Royal Society of Edinburgh on April 6, 1846. Maxwell had a college education at University of Edinburghthen proceeded at Cambridge University’s Trinity College which he completed in 1854 and was selected as Chair of Natural Philosophy atUniversity of Aberden at the age of 25 years. He is known for his research on the field of kinetic theory and thermodynamics, optics, and his greatest breakthrough in the field of electromagnetism projected into the Maxwell Equations.

Maxwell has a remarkable ability in performing mathematical abstractions to explain a physical condition. This can be seen in his analysis of the stability of the saturnus rings he describes using mathematics by predicting that the Saturn rings are composed of a set of tiny particles in very large quantities, if the farther from the center of mass saturn, the less the number of particles is due to the influence of increasing Saturnian gravity small. Then after more than a hundred years later that is in 2004, the new theory was successfully proven by NASA.

Maxwell’s ability to describe statistical behavior on classical gas molecules and his most beautiful works in explaining the symmetry of electricity and magnetism as electromagnetic waves and mathematical explanations that tell that light is an electromagnetic wave; shows Maxwell’s unquestionable genius as a physicist whose influence stands side by side with Newton and Einstein.

If talking about the technology around us then can not be separated from the great contribution of the Maestro Electromagnetism. From the start of radio, television, radar, wifi and bluetooth are some examples of current technology that beranasakan theory of electromagnetic field that has been summarized by Clerk Maxwell into four Maxwell equations. Physics World magazine , one of the largest physics magazines in the world that covers all areas of physics, chose Maxwell’s Equation as ” the most important equations of all time “.

From the beginning is often called the term ‘electromagnetism’, what exactly is electromagnetism? Electromagnetism is a process that explains the linkage between the electric field and the magnetic field that includes its propagation, its interaction, and how the two fields affect other objects. The major principles in electromagnetism have been summarized by Maxwell into his four famous equations which will try to explain the author simply without complex mathematics.

  1. Gauss’s Law

Maxwell’s first equation is Gauss’s law. Gauss’ law explains the behavior of the electric field around the electrical charge.

The above equation is a manifestation of Gauss’ law. The right-hand side of the equation shows the type of volume charge ρ v that describes how tightly the set of charges in a given volume; then the left side of the equation showing a radiant electric field D that is symmetrical in all directions.

Figure 2. Emission of electric field lines in the plane (a) positive charge, (b) negative charge (https://courses.lumenlearning.com/physics/chapter/18-5-electric-field-lines-multiple-charges /)

It can be concluded that there will be a symmetrical (symmetrically visualized) electric field radiated in any direction through a volume field sourced from a certain amount of electrical charge in the volume field (the emission will come out if the charge is positive and will go in if the charge electricity negative). Or simply, if there is an electrical charge in a certain position there will be electric field radiation in all directions. A plurality of electric field jets (illustrated by field lines) penetrating the volume field will be denser if the charge is multiplied (provided that the load in the volume has the same pole that is positive or negative only if there are several charges with different poles then the field of electric field will reduce each other) or the volume is reduced which means  its value will be greater. This is the theory and the mathematical form that underlies the explanation of the electric field direction of the positive and negative charges that have been studied since junior high.

  1. Law of Gauss Magnetism

The Law of Magnetism Gauss states that the total jets of magnetic field lines penetrating a given volume are zero ( B is a magnetic field).

This happens because the magnet must have two poles (magnetic dipole) or no magnet that has only one pole (no magnetic monopol). Then why in the absence of a magnetic monopolist causes the total emission of a magnetic field penetrating a given volume is zero? Yep the following explanation.

Figure 3. Emission of magnetic field lines in a magnetic dipole (https://brilliant.org/wiki/magnetic-field-lines/)

The absence of a monopole magnetic means the presence of a magnetic dipole. Magnetic dipole shows that the magnet will always have two poles of the north and south poles; and it is impossible to consist of only the north pole or the south pole only. We know that the direction of the magnetic field lines from the north pole to the south pole. Imagine we put a magnet inside a cube. After that, the magnetic field lines will come out of the north pole, pierce one side of the cube (call it A side) and then enter through the opposite side of the cube (call it B side) to the south pole. The number of magnetic field lines radiating out from side A will be equal to the number of magnetic field lines radiating in from side B; so the total emission of the magnetic field lines will be equal to zero.

  1. Faraday’s Law

Now we go into the third Maxwell Equation that is Faraday’s law. Faraday was an experimental physicist who succeeded in proving that the speed of changes in the magnetic field and the effective cross-sectional area (the effective cross-sectional area is the area penetrated perpendicularly by the magnetic field) would produce induced electrical current and induced voltage (induced electrical current and induced voltage are terms for the current and the electric voltage generated through the change of the magnetic field per unit of time, or in this case, the word induction can also be understood along with the word stimulation). The magnitude of the magnetic flux that is the scalar multiplication of both magnitudes. Then Lenz complements Faraday’s law by saying thatpolarity (induced poles) of induced voltage is such that the induced voltage tends to produce currents that give rise to a magnetic field (the lenz field) against the change of magnetic flux through the loop ; the statement is referred to as Lenz’s law. So the mathematical form of Faraday’s law is

with ε and Φ are the induced voltages and magnetic flux respectively. The negative sign (the result of Lenz’s law), indicates that the resulting opposite poles of the induced voltage will produce an electric current in the opposite direction causing the magnetic field lines to be produced in the opposite direction of the initial magnetic flux to act as the inducer. The opposite here means that imagine a magnetic field coming from the smartphone screenor our laptop with the magnitude that changes with the lines of the field towards us. Then by clenching the four fingers of our right hand (as the direction of the electric current) and the thumb pointing towards us (as the direction of the magnetic field lines) we will be able to know the direction of the resulting electric current that is (supposedly anticlockwise). However, the direction of the resulting induced electrical current is opposite from that, ie clockwise with the positive and negative poles of the induced voltage adjusting because the electrical current visualization is flowing from the positive pole to the negative pole. The direction of the current and induced magnetic field can be known by the left hand rule (as opposed to as it should be, please try!).

By associating the equation with the relationship between the electric-electric field voltage; and the Stokes theorem is obtained the following equation

The above equation is the third Maxwell equation. Whew, starting from the connection of electrical voltage, electric current, and magnetic field; it turns out the relationship between electric field E and magnetic field B ! (Here is not explained how the mathematical process, because it is long enough).

The interpretation of the third Maxwell equation above is that the magnetic field changes will produce an electric field whose direction of electric field lines surrounds the magnetic field lines (perpendicular to each other) with the relationship between the direction of the two fields can be determined by the left hand rule (four fingers the left hand is clenched and the thumb is fixed The direction of the thumb shows the direction of the magnetic field and the fist of the other four fingers indicates the direction of the electric field surrounding the magnetic field).

  1. Ampere-Maxwell’s Law

Finally, we have reached the last Maxwell equation which will explain that it turns out that not only changes in the magnetic field can produce an electric field, but changes in electric fields can also produce changes in magnetic fields! Although the basis of Maxwell’s fourth equation is the law of Ampere but Maxwell is the one who sparked the idea of ​​the symmetry between the electric field and the magnetic field (Briefly symmetry can be understood as the action of reaction If X then Y, then vice versa if Y then X). The idea of ​​Maxwell is simple, he knows that in this world symmetry plays an important role. So if a magnetic field change can produce an electric field then a change of electric field will certainly produce a magnetic field.

Based on his experimental results, Ampere found that when there is an electric current flowing in a conductor it will produce a magnetic field that surrounds the electric current is based on the rules of the right hand (the thumb as the direction of electric current and the fourth fist finger other as the direction of the magnetic field); and based on a sharp intuition equipped with mathematics, Maxwell sparked that changes in the electric field would produce a magnetic field. The idea is intertwined with another idea which states that the electric current can not only flow on the conductor but also can flow on the insulator called the displacement current . The shifting current is generated from changes in the electric field.

The above equation is the fourth Maxwell equation by J is the electric current density is the amount of electric current that flows per unit area, and  the flow shifts resulting from changes in the electric field D . Interpretation of the fourth Maxwell equation as follows, the electric current flowing in the conductor J will produce an H magnetic field that travels around the conductor and if the electric field D within the conductor is altered it will produce a D shift current which also has a contribution in generating magnetic field around it.So what if in the isolator medium like a vacuum or air? Then the electric current J will be lost so as to produce the form of the fourth Maxwell equation in a vacuum that is only influenced by changes in electric field (current shift),

Perhaps this pure contribution from Maxwell looks small, but in fact this contribution is enormous. The idea of ​​the symmetry of the electric field and the magnetic field is what unites the concept of all equations in electricity and magnet so that the term ‘electromagnetism’ occurs; then this idea is also the basis of the concept in explaining the propagation of electromagnetic waves until finally found that the propagation speed of electromagnetic waves always the same if it is on the same medium that is the speed of light propagation. So it can be concluded that light is a new electromagnetic wave can be proven through experiments by Heinrich Hertz in 1888, 9 years after the death of Maxwell.

Figure 4. The monument of four Maxwell equations in the theory of electromagnetism (https://en.wikipedia.org/wiki/James_Clerk_Maxwell_Foundation)

In addition, the development timeline follows from the theory of electromagnetism

Figure 5. Ten physicists who contributed to the development of electromagnetism theory from the late 18th century to early 20th century (http://www.clerkmaxwellfoundation.org/Maker_of_Waves.pdf)

Of the 10 physicists who contribute to Maxwell’s development of electromagnetism theory only contributes to the mathematical descriptions (theoretically) as well as the only ones who can provide precise predictions about new concepts and ideas before experiments are successful.

For the related explanations of how the Maxwell concept and equations can prove that light is an electromagnetic wave will be discussed in an upcoming article. See ya soon !

Reference

  1. A & E Television Networks. (2015, 24 June). James C. Maxwell Biography. Retrieved 6 April 2018, from https://www.biography.com/people/james-c-maxwell-9403463
  2. James Clerk Maxwell Foundation. “__”. Maker of Waves. Retrieved 6 April 2018, from http://www.clerkmaxwellfoundation.org/Maker_of_Waves.pdf
  3. James Clerk Maxwell Foundation. “__”. Saturn’s Rings. Retrieved 6 April 2018, from http://www.clerkmaxwellfoundation.org/Saturn-s_Rings.pdf
  4. JJ O’Connor and EF Robertson. “__”. James Clerk Maxwell. Retrieved 6 April 2018, from http://www-groups.dcs.st-and.ac.uk/history/Biographies/Maxwell.html
  5. Maxwells-Equations. (2012). Ampere’s Law. Retrieved 6 April 2018, from http://www.maxwells-equations.com/ampere/amperes-law.php
  6. Maxwells-Equations. (2012). Faraday’s Law for Induction. Retrieved 6 April 2018, from http://www.maxwells-equations.com/faraday/faradays-law.php
  7. Maxwells-Equations. (2012). Gauss’ Law. Retrieved 6 April 2018, from http://www.maxwells-equations.com/gauss/law.php.
  8. Maxwells-Equations. (2012). Gauss’ Law for Magnetism. Retrieved 6 April 2018, from http://www.maxwells-equations.com/gauss/magnetism.php
  9. Sci-Show. (2016, 15 September). Great Minds: James Clerk Maxwell, Electromagnetic Hero. Retrieved 5 April 2018, from https://www.youtube.com/watch?v=b2cVLHozb9k
  10. Surya, Yohannes. 2009. Series of Materials for Physics Olympiad Preparation: Electricity and Magnetism. Tangerang: Kandel.
  11. Tiger Webb. (2015, 1 December). James Clerk Maxwell: The Greatest Physicist You’ve Never Heard of. Retrieved 6 April 2018, from http://www.abc.net.au/radionational/programs/scienceshow/james-clerk-maxwell:-the-greatest-physicist/6990508
  12. Wikipedia. (2018, 30 March). James Clerk Maxwell. Retrieved 6 April 2018, from https://en.wikipedia.org/wiki/James_Clerk_Maxwell
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Christopher Farrel, High School Indonesian Student that Do Research in Data Compression and Invited by Google

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Christopher Farrel Millenio Kusuma, 8th State High School student was once confused when his internet quota is going to run out but “dying” wants to download a game . “The thought of how to reduce data size to be able to download one game only,” said this bespectacled adolescent when found brilio.net at SMAN 8 Yogyakarta, Friday (24/11). Thanks to the experience quota thin, the students are usually called Farrel can play to Google headquarters in Mountain View, United States. His research entitled “Data Compression using EG and Neural Network Algorithm for Lossless Data” made the IT giant curious. 

The arrival of the couple’s son Monovan Sakti Jaya Kusuma and Hening Budi Prabawati to “Uncle Sam’s Country” is not for a vacation, but instead fulfills the invitation of one of the world class company, Google. Google’s invited experience becomes a historic event in life and can never be forgotten teenager whose full name is Christopher Farrel Millenio Kusuma.

Christopher Farrel at Google Office with the flag of Indonesia. Source: brilio.net

The idea of ​​research that led to Google started from trivial. Farrel wants to download a  game . However, the data quota is limited. At that time, Farrel was still in high school. “Initially it wanted to download the game , but the quota is limited, but I really want to play the  game  . Then the thought, how to minimize the  game  , let me play, “he said while laughing. From his desire to play the  game  , Christopher Farrel Millenio then began to search the internet how to minimize the data. From the search, this 17-year-old teenagers find  data compression or  data compression. “I am looking for fun then research and it turns out, data compression has not been so developed, yes then came the idea to research because the impact is wide as well, “he said. “From there tau whose name is Zip and Rar. How do I create one? Kan it the 90s all, there is no progress? “He said.

Zip and Rar are compressed files that allow multiple files to be collected into one with a smaller size. Zip and Rar can simplify splitting your files in one package. The file will also be more easily moved due to its reduced or compressed size. Zip and Rar file formats are often used by people to make the size of a file smaller.

After about one and a half years, the teenager born in Yogyakarta, January 1, 2000, successfully created a research entitled “Data Compression Using EG and Neural Network Algorithm for Lossless Data”. The results of his research was then submitted to the arena of competition in Indonesia both regionally and nationally. Because, according to him, there is no Indonesian people who examine specifically about  data compression,but the positive impact is so great. However, his efforts did not work. Filed since 2016, Farrel’s research proposal has always been rejected. “Yes, if counted to 11 times is not accepted,” he said.

The rejection did not discourage Farrell. Precisely it even makes the spirit of adolescent with glasses burning. He continues to refine his research both from the theory to the writing. Therefore, this Yogyakarta-born teenager believes one day his research will be accepted. “(I) do not blame the committee, but myself and evaluate. Maybe my way of delivering it is less precise so they are difficult to understand, so it continues to be refined to the point of making eight versions, “he said. “Thomas Alva Edison 1000 times failed,   my new mosok11 times continue to give up. To be Alva Edison I need 989 times to try, I count and hold for a long time, still long, “he explained.

Until one day, Farrel saw an announcement from Google in the online  media  about the research contest Nor did he want to miss the opportunity by submitting a proposal to the technology giant. “His name  submit reset , I have resigned and baseball thought accept. Uh, it turns out after a week there is an   incoming e-mail , telling me I escaped, “said Farrel.

After his proposal was passed, Farrel still had to undergo an interview to ensure his research was genuine. In the interview, Farrel was asked about the rationale, theory, until the impact of his research. “When passed the interview, one I think, the money, because there is no cost of accommodation. Then I only have two weeks to take care of the letters, including finding accommodation money. But it turns out God gave way, can sponsor and take care of visa can be fast, until finally leave, “he said.

On February 15-20, 2017, Farrel was in the Google Mountain View office, California, USA. While in Google’s office, Farrel presented his research in front of all participants from a number of countries who escaped. “I am the only one from Indonesia, and during that there are presentations, discussions,  sharing  with people from other countries who qualify. We each accompanied a mentor from Google, “he explained. Farrel said he was happy to be in Google’s office. Farrel was amazed by the systems and technologies that were implemented in Google’s office. “It’s so nice, so his office is such a complex, clean and incredible technology, there are smart cars, electric cars, and bicycles. The internet is also very fast, “he said

Farrel successfully compresses 50% to 90% of its original size

In a test run at the time invited on the Black and White event, Farrel managed to compress photo files that size 257 KB to 131 KB and text file size of 1000 KB to 16 KB only. This invention is called Reverse Genetic Algoritm which extension. But unfortunately Farrel research results can not be enjoyed by the general public because it is still a code or source code and has not been an application that can be directly used.

How, is the friend of Warstek unmotivated? Let’s work to be like Farrel!

Reference:

[1]  5 Facts Christopher, high school student in Yogyakarta who invited Google . (Retrieved 17 February 2018)

[2] His research was rejected 11 times in Indonesia, Students from Yogya It Was Invited Google . (Accessed on February 15, 2018)

[3] Zip and Rar . (Accessed on February 15, 2018)

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Stephen Hawking, Physicist Who Makes Black Holes So Glow

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Recently, March 14, 2018, Stephen Hawking’s name has become more resonant than ever before. The news of the death of the most famous physicist after Albert Einstein is filled the virtual world, drove across the vast ocean, to our country Indonesia. Stephen Hawking rested forever at the age of 76.

Stephen Hawking is often dubbed the smartest living human being. There is little pride in our minds because it is lucky to be able to live as a great scientist. But now that sense of pride has gone, along with the last breath that blows from this physicist.

Stephen Hawking, age close to 76 years (January 8, 1942 – March 14, 2018)

One of Stephen Hawking’s great contributions to physics is his theory of black holes . Black hole is a very massive object so no one can escape from the pull of gravity.

Initially black holes are only considered as mathematical objects born of the general theory of relativity only. But now we know that the black hole really exists in the real world. [1]

What is Stephen Hawking’s contribution to the theory of black holes? Consider the following explanation.

The Stained Space Is Not Really Hampa

Our reasoning is shaped by experience. At first we thought that heavy objects fall faster than light objects. This is because in everyday life we ​​do see it that way. But after we look more closely it does not. Heavy objects and light objects fall together when air resistance is removed. This is the reason why the theory of relativity and quantum theory is difficult to digest by reason. In everyday life we ​​have never dealt with super-fast objects or super-small objects. That’s why we should not be too confident with our common sense .

The law of conservation of energy is a very logical law, in accordance with our daily reason. It is impossible for matter to appear suddenly from the void. But it turns out two plus two is not always equal to four. Quantum theory has modified the law of conservation of energy through a principle whose name is Heisenberg’s uncertainty. Material may suddenly emerge from the absence provided that it vanishes immediately. The consequence of this is very spectacular. Heisenberg’s uncertainty principle gives us a new understanding of what voidness is.

What comes to mind when we hear the word “hollow”? Our reason describes emptiness as emptiness, nothingness, dark black, without anything there. But it turns out that quantum theory says something else. The vacuum is not really empty. The vacuum was full of activity. Couple particles and anti-particles suddenly appear then meet again and mutually eliminate. Appears to disappear, reappear, disappear again, and so on. According to quantum theory, vacuum is a very crowded place. [2]  This quantum theory is used by Hawking to describe black holes.

Theory of General Relativity vs. Quantum Theory

Today almost everything that exists in the heavens and on earth can be explained by two major theories of physics, the theory of general relativity and quantum theory. The general theory of relativity is able to explain massive objects such as stars, galaxies, and the universe. Meanwhile, quantum theory is able to explain small objects such as atoms, protons, and electrons.

Normally large mass objects must be large in size so we do not need to review them with these two theories at once. But there are two places where small objects have a very large mass at the center of the black hole and at the beginning of the universe.

To find out what happens at the center of the black hole as well as at the beginning of the universe, we need to unite the general theory of relativity with quantum theory. This theory of unification is the dream of Stephen Hawking, Theory of Everything .

But it turns out to unite the two (the theory of general relativity and quantum theory) is not easy. Until now we still do not have Theory of Everything so we still can not analyze what happened at the center of the black hole and at the beginning of the universe.

Stephen Hawking has not been able to figure out what’s going on in the center of a black hole because he has not succeeded in composing Theory of Everything . But he has made the first step to get there. Before approaching the center of the black hole, it is better to grope the surface first.

Researching the surface of a black hole does not need to use Theory of everything in its actual version because the gravity there is not as strong as gravity at the center of the black hole. Simply use quantum theory but in a curved spacetime background . [3]

Hawking Radiation

What happens when Stephen Hawking sees the surface of a black hole using quantum theory? This is where the revolution takes place. Hawking sees a pair of particles and anti-particles that appear on the horizon of a black hole. Black hole has a horizon or a safe distance. Any object that includes light when it has crossed the horizon will not get out again. That’s why the black hole is black, because no light can come out of it.

Hawking Radiation

Some of the particle and anti-particle pairs that appear on this horizon will not be able to meet again to cancel each other out. As a result, one particle enters the black hole and the other is released as radiation. Particles that enter the black hole have a negative mass that will reduce the mass of black holes.

From the outside, black holes appear to shrink while emitting radiation. Radiation is then known by the name of Hawking Radiation . It is a revolution because the former black hole is known as an object that does not want to remove anything that has been swallowed. But Hawking said that the black hole turned out to emit radiation alias “shine”. [4]

REFERENCE:

[1] Science Channel. 2014. Through the wormhole – The riddle of black hole . https://www.youtube.com/watch?v=K8QfYWKoTDA accessed March 14, 2018

[2] Krauss, Lawrence. 2012. A Universe from Nothing . USA: Free Press

[3] Carroll, S. (2004). Spacetime and Geometry, An Introduction to General Relativity Chicago: Addison Wesley

[4] Muon Ray. 2015. Stephen Hawking Lecture – How to Escape Out of a Black Hole. https://www.youtube.com/watch?v=h_d7O9JGo_s accessed March 14, 2018

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