Monday, 20 June 2016 01:48

What is light?

Written by 

Date: June 19, 2016

To: Charles Chidi Achodo

From: Ozodi Thomas Osuji

 

Subject: Response to your question on the nature of light

You asked: does light have many forms? I am supposing that you want me to differentiate between what religionists call spiritual light and what we in the phenomenal world call light (optics).  The answer is yes.

God is light but that light is not the light we understand in the temporal universe.  As I pointed out in my paper, yesterday, the paper that you were responding to, there is one stream of light and that light is God. Each of us is a particle in that wave of light.

Wave (God) and particles (sons of God, us,) are one.

Contemporary physics has recognized that the idea of wave and particle is a manner of talking, for in fact they are the same.  If you recall Thomas Young's famous experiment of 1803, you know that if you shine a particle of light on a slit (hole) it goes through it as a particle. If you have more than one slit, holes, and shine the same particle of light on them somehow that one particle of light divides itself and simultaneously goes through all of the holes you made ... as if it has a mind to know what you want it to do!

By the way, this is what is behind your email. If you type your email letter what you did is put information into an electron and hit send, and it goes to the slit/hole, address you asked it to go to; if you have billions of addresses and ask it to go to them, hit send that one electron somehow divides itself and goes to all of them, each containing the information you had put into the original electron. How did one particle of electron divide itself and go to many email addresses? This is an interesting question, is it not? Quantum physics works in a mysterious way!

We simply do not understand why these things work the way they do; all we know is that they do work; they are beyond our common sense understanding of phenomena.

Use quantum physics to do work but do not ask why it works; this is what professors of particles physics tell their students.

Even Albert Einstein quit trying to explain quantum mechanics; initially, he rejected it, for, to him, God does not play dice; he harassed Neils Bohr whose Copenhagen school propagated it, but later accepted that it works.

These days, quantum physicists say that the idea of particles and wave is conceptual and not separate reality; in effect, light is neither wave nor particle but something that does whatever you want it to do; if you ask it to behave as a particle it does so and if you ask it to behave as a wave it does so...so what is light? I do not know what is light.

What I will do below is review the nature of light as is taught at secondary schools and universities.

If you recall from your secondary school physics, physics is divided into five areas: mechanics, heat, light, electricity and sound. We all had to study those during the first four or five years of secondary school.  The study of mechanics, heat, light, electricity and sound is now called classical physics.

During the next two years of secondary school (our so-called high school in Nigeria) we had to study what is now called new physics; that is, quantum physics.

Light is a subject in physics; the field is called optics. It is a subject for a life-long study. What I will do here is try to summarize its salient points in a few pages.

I am generally very verbose and if left unchecked could write  hundreds of pages on light but I will try to discipline myself and without looking at any book just  write what comes  into my mind, what I remember about light from my college days. Here we go.

Light is an electromagnetic radiation; it is the stuff with which we see. Human beings have always wanted to understand the nature of light. Thus, from ancient times (Indians, Greeks etc.) bright minds speculated about its nature.

Isaac Newton studied light (he called it optics).  He believed that light is wave.  Eugene Huygens in the mid-1600s disagreed with Newton and said that light is particles.  Because Newton was a much more famous physicist his view of light prevailed.

As noted, in 1803 Thomas Young, an English physicist performed his famous experiment that proved that light is particle.

In the early 1920s the French man, Louis Broglie replicated Young's experiment, this time using electrons hence establishing that electrons and other particles behave like light, split to go through holes.

Young did not put to rest the debate as to whether light is particle or wave (quantum physics now uses the term wave-particles, for the two are seen as one phenomenon).

In 1900 Max Plank, the German founder of quantum mechanics did his black body experiments. If you heat a black body, say, a piece of iron you notice that it gets hot and depending on the level of hotness/high temperature its color changes.  When the black colored iron is heated it initially feels hot and then turns red; if you keep heating it, it turns white in color!

Plank observed something else; it appeared that light does not just produce wave of light but also particles of light; he called those particles quanta, units of light...hence the term quantum mechanics. Light is in units that move hence motion or mechanics.

Plank introduced the idea of light as in units, quanta. Albert Einstein read his paper and in 1905 wrote his famous paper on the photoelectric effect of light.  Einstein shone light on a hot iron and showed that the light was knocking off particles from the hot iron. In other words, light is in units that can behave as if they have mass, weight by knocking off electrons from hot objects.  Einstein called the units of light photons. Thus, Einstein contributed to quantum mechanics.

The other main actors in quantum mechanics are J. J. Thomas who discovered the electron in 1897, Earnest Rutherford who discovered protons in 1911, James Chadwick who discovered neutrons in 1932; Neils Bohr in 1913 showed how electrons circled nuclei of atoms;  in 1925 Werner Heisenberg gave us the mathematics of Quantum mechanics and also established the Uncertainty Principle which says that you can ascertain  the location of an electron and  its velocity but not both at the  same time; if you see one you cannot see the other; Emil Schrodinger in the same year wrote wave mechanics equations that described the behavior of particles inside atoms; Bohr later refined complementarity principle that says that particles can act as wave or particle (hence wave-particle concept).

There are other actors in quantum mechanics, such as Lise Meitner, Otto Hahn, Strassman, Thomas Oppenheimer (who led the Manhattan project that exploded the first atomic bomb in 1945, in New Mexico), Enrico Fermi, James Wheeler, Murray Gel-Man (who arranged quarks into up and down quarks), James Feynman, Steven Weinberg, and Eugene Wigner and so on.

(Please notice the absence of African names in the list of twentieth century geniuses in physics and chemistry that I just delineated!)

Einstein, by the way, did the observation of the photoelectric effect of light at age 26 when he worked as a patent clerk in Switzerland; it was for this paper that he won his only Nobel Prize; he did not win the Nobel for his other papers on Special relativity and later General relativity.

Isaac Newton discovered the theory of gravity at age 23. James Watson, the co-discoverer of the DNA was barely twenty when he did so. Alexander Flaming who discovered penicillin did so in his twenties. Most discoverers in science do so in their twenties! If you are over age 35 you are no good to science, really! I doubt that major universities will hire you to teach science if you are over 35 years old.

Light has the quality of luminosity. It has many sources; on earth its primary source is the sun. Yesterday, I talked about how inside stars hydrogen (which has atomic number 1 and atomic weight 1...atomic number is determined by the number of protons in an atom; hydrogen has only one proton, is the simplest element; its atomic number is 1 on the elements periodic table... atomic weight is determined by adding the number of protons and neutrons (electrons have negligible mass so it is pointless adding  them to the weight); in the case of hydrogen the atomic mass is 1 for it has one proton and no neutron;...in the case of helium  the atomic number is 2 and the atomic weight is 4...helium has two protons and two neutrons and two electrons; the atomic number of uranium, the heaviest element is 92 because it has 92 protons in its nucleus and the atomic weight is 238...add 92 protons and 146 neutrons you have 238).

Well, in the core of stars two hydrogen atoms fuse into helium and in the process produce heat and light. Here, I will skip the various steps in the fusion process, it is too complex for public discourse...the process is called nucleosynthesis.

The heat and light produced by nuclei fusion inside stars may take millions of years before reaching the surface of the stars! The surface of stars is like bubbling hot water; this is from the heat and light coming from inside the stars churning the gases on the surface of the stars.

Heat and light leave stars and travel at the speed of light in vacuum, which is 186, 000 miles a second; it takes light about ten minutes to travel from our sun to us, 93 million years away; it takes light from the moon about a little over a second to reach us, 250, 000 miles away; if you, on earth light a candle a person on the moon will see the light from your lit candle in a little over a second!

As you know, plants pick up light from the sun and convert it to starch through the process of photosynthesis. Plants store that starch, sugar and we, animals, eat vegetables and absorb that starch, carbohydrate.

When you eat an apple or any other fruit you are eating sugar, starch that plants had converted from the sun's light energy. Your body is nourished by energy from the sun! Your body is literally an extension of the sun!

Our bodies, in turn, transform sugar, starch from plants to energy with which they do their work.  Our bodies are mechanical and heat systems that use starch and other sources of energy to do work. If you do not eat food you do not have energy to do work in your body.

As our bodies do work with the starch from plants they produce heat energy and that heat is gotten rid of from our skins, sweating and breathing etc.  The point is that our bodies are thermal energy systems, they produce heat and light.

If you recall from your secondary school course on heat, you know that heat is an energy that when hot becomes mechanical, and move things. We boil water and use the heat energy in that water to move trains, ships and other steam engines.

(The study of heat, by the end of the nineteenth century, had established the laws of thermodynamics, including the law of entropy that I talked about yesterday...all systems lose energy and eventually exhaust their energy; your body loses energy daily and thus will die; our universe will eventually exhaust its energy and die.)

Water is a compound of hydrogen and oxygen, actually a molecule (what is the difference between compound and molecules?); do you still remember how chemical mixtures, such as compounds, are formed; remember the idea of valence, how the outer electrons shells inside atoms are combined with the electrons in other elements to form compounds? Ah, chemistry, neat stuff!

Your car runs on heat energy; the gas you put into your car contains energy from the sun stored in the ground. That petroleum is heated and is transformed to mechanical energy and that makes your car move.  Your car has internal combustion ability; that is, it internally boils gas and uses its heat energy to do all kinds of work. When you turn your car's key, ignition to start your car you start the petrol boiling and that produces heat energy and heat energy is transformed to mechanical energy that moves your car.

You know from secondary school physics that energy is transformed to many forms but is never destroyed or lost. This is called the law of conservation of energy. The total quantity of energy in the universe remains constant but we do transform one source of it to another. Consider what happens in your car...you have taken petroleum (chemical energy) and converted it to heat energy and that heat energy is converted to mechanical energy that moves your car.  That same energy is converted to light energy...the light in your car...and to electrical energy, the electrical system in your car and to sound energy that enables you to hear your car's radio.

The point is that one source of energy can be transformed to other types of energy: mechanical (kinetic), heat, light, electricity and sound and chemical. (You probably have noticed a contradiction here: if energy is never lost how come the law of entropy talks about energy loss that wound wind down the universe...where would that energy go to? That subject is for advanced students of chemistry and physics to ponder! Ludwig Boltzmann grappled with that question.)

Albert Einstein showed us that energy is the same as matter/mass. You can convert any source of energy to matter and any source of matter to energy. Take a piece of wood (which is mostly carbon), burn it and you convert it to heat, light and sound and mechanical energy. You can capture the heat and light and convert them to electrical energy or back to wood. See Einstein's famous equation:  E=Mc2.

Some animals do produce their own light, such as fireflies and bats (this is called bioluminescence).

Light travels at a given speed in vacuum (186, 000 miles per second).  Light can be slowed down by all sorts of mediums, objects.

Light is reflected (shine light on something and it reflects it back to you...in fact, our seeing is reflected light...light, photons strike an object, say, your wife's body and that light is reflected from her body to your eyes, retina,  and sends a picture of her to your brain and you see her picture in front of you.

Light takes pictures of whatever it strikes and carries them away with it...in the future science will have the technology to let us see the pictures of our ancestors gathered in their societies, for light took pictures of them and took those pictures with it as it travels in space; those pictures are somewhere in space...as you sit  in your room light is taking pictures of you and traveling with that picture in space so that in the future, millions of years from now,  folks will have the technology to see you in your 21st century room!.    The point here is that light has reflection and takes photos (photos is actually a name derived from photons, light!).

Light has refraction. That is, light does bend upon hitting certain medium. If you shine touch light on a bucket full of water you notice that the light is bent as it goes through that water. This is called refraction.

Light is absorbed by certain mediums and others allow it to go throw. Light goes through your window's glass but  does not so easily go through the wall in your house; it does go through the walls but you may not readily see it (neutrinos are particles that go through everything, our bodies, walls, mountains etc. without been obstructed or seen...when a particle like neutron decays it transforms itself to proton, and electron and neutrinos...if you separate neutrons from protons, from the nuclei of atoms, it decays within ten minutes...protons live for as longs as this universe lasts!).

In 1896 Henri Becquerel, a French physicist, building on the newly discovered X ray by the German, Roentgen, discovered that the nuclei of elements/ atoms do decay and produce radiation (light)...there are many types of radiation, including alpha, beta and gamma ray (radiation).

Marie and Pierre Curie around 1900 studied uranium and came to understand that its nucleus decays into other elements (such as polonium) and produce radiation, light.

In the late 1930s, Lise Meitner, a German female physicist, showed us how to split uranium nucleus hence produce atomic bombs. Uranium is composed of 92 protons, 92 electrons and 146 neutrons...since there are more neutrons than protons in uranium it is an isotope of...?

An isotope is where an element has more neutrons than protons...if you remove some of the neutrons in the nucleus of uranium it becomes lead, the lead in your pencil!

Now, pay attention, my man and learn about nuclear bombs. Meitner showed us that if you can isolate neutrons and use them to keep striking on the nucleus of uranium that you will split the strong nuclear force holding protons and neutrons together and release energy in the form of radiation, hot light. This is exactly what the atomic bomb does! This is called nuclear fission, as opposed to the nuclear fusion that takes place inside stars.

In atomic bombs we split the nuclei of uranium with neutrons and break the strong nuclear force holding protons and neutrons together and release radiant energy that can destroy cities.

Just think about it. A small piece of uranium contains enough energy to destroy Lagos, Nigeria (as was demonstrated at Hiroshima and Nagasaki in August 1945 when the USA dropped the first two atomic weapons on Japan (to end the Second World War).

We have since added hydrogen bombs to our arsenal for destruction. To have hydrogen bombs we follow two stages; first, we initiate chain reaction in uranium nuclei by using neutrons to split uranium nuclei and the enormous heat and light generated by that nuclear fission approximates the heat in the core of stars and that heat is used to fuse, combine hydrogen atoms into helium atoms, as is done inside stars, and release tremendous heat and light, aka radiation.

The released radiation is used to destroy cities and people on a massive scale (both the USA and Russia have hydrogen bombs).

But do not despair, for the heat and light (radiation) produced by splitting atoms can be captured and used to provide cities with electricity. This is what nuclear plants do; in their concrete silos, uranium nuclei is split and energy is released; that energy is captured and transformed to electrical energy and used to give cities electrical power.

That is to say that that which is dangerous is also good!  The means of producing nuclear weapons is used to produce nuclear energy to power our cities!

The gods are funny; they give us death and life! Hence the Hindu god called Shiva...the god that give us life and also kill us!

Good and bad are inherent in our world. It is a world of opposites, after all; if you have good you must have bad; if you have pleasure you must also have pain. Do you have good news today and feel good? Tomorrow you will get bad news and feel bad! Get it?

By the way, many of the people who discovered nuclear weapons, realizing the power of death they unleased, turned to religion to find solace for their guilty conscience; Oppenheimer, Schrodinger and so on turned to Hinduism. Those of us with knowledge on how to do great harm to humanity often turn to God for salvation. Isaac Newton, having written his book, Principia Mathematica in 1687 turned away from physics and turned to God. He wrote more books on God than on physics; the same holds for the genius of all times.

Now, to your question: are there many types of light; the answer is obviously yes. There are many types of light (radiation), including visible light, invisible light (your dog sees a type of light that the human eyes cannot see), infrared, ultra violet, alpha, beta and gamma ray, microwave, radio wave and X rays. I do not have the time to explain these different types of light; read up on them.

You asked a question regarding compositions. You said that the human body is composed of many things and if light is not composed of anything how can I say that the human body is light.

This question emanates from lack of understanding of what I wrote.  The human body is composed of twenty six elements. In my paper, I showed the composition of each of those elements.  What is composed must eventually decompose, so our bodies will eventually decompose, die and the elements separate; the separated elements will eventually decay to particles and the particles will decay to quarks and electrons and those eventually decay to light.

Is light composed? What is it composed of? Light has no mass and, as such, is pure energy; light is energy that is not yet in the form of matter until it is transformed to matter.

I pointed out that whereas there seems wave and particles in light that both wave and particle are the same; any particle of light can act as wave of light; and any wave of light can act as particles of light.  In effect, light is one thing that performs seeming two different functions: wave and particular.

Listen, my man, we really do not know what light is!

With regard to your other question regarding purpose and meaning in life, well, have you heard of existential philosophy?

Existentialism says that there is no apparent meaning and purpose to our existence.  Of course, as individuals we seem to have purposes. When I was ten years old I saw a man from Owerri who returned from America; he came to visit my father at Lagos; he told us that he has a PhD; he said that the PhD is the penultimate level of education. There and then I resolved to go to America and have a PhD. That is, I gave myself a purpose.  Despite the civil war that disrupted my secondary schooling, I had PhD at age 28 and was a professor thereafter.

The point is that people do give themselves purposes and work towards them. But if you ask larger questions like, does life have a purpose? It is kind of hard to find a purpose to our lives!

Let us see; we are born and struggle for food, get food, eat food and stay alive. Give or take, a hundred years later we die. Our bodies are eaten by worms.  In scientific terms, our bodies decay to the twenty six elements that compose them and in time those decay to particles and eventually everything in the known physical universe decays to photons (and to nothing). We have not figured out where the initial light that got the universe going came from (if from nothing then we are nothing).

Since we die and decay would you say that our lives have meaning? Obviously, we have temporary meanings but ultimately our lives on earth seem meaningless!

Should we then despair? Of course not. It is when folks realize that their earthly lives have no real purpose and meaning that they start seeking spiritual answers.

In my early thirties I quit teaching at one of California State Universities and studied psychology and thereafter comparative religions. I was searching for meaning, for I did not see meaning in regular jobs and the world. That search took me to comprehensive study of Hinduism, Buddhism, Taoism, Gnosticism and Zen and Western and Oriental philosophies.

By the way, where are African philosophers? The West has its Plato, Aristotle, Bacon, Descartes, Spinoza, Pascal, Leibnitz, David Hume, George Berkeley, Thomas Hobbes, John Locke, Montesquieu, Voltaire, Rousseau, Kant, Hegel, Schopenhauer, Karl Marx, Nietzsche, Henry Bergson, William James and others and the East has Shankara, Ramanuja, Confucius, Buddha, Lao Tzu and others. Africa has none!

Africans do not even have a person who has made seminal contribution to physics, chemistry, biology, earth science, astrophysics...and I am on top of those fields and can tell you who is who in them. We are one giant nothing, empty vessels that make a great deal of noise!

All we do in Nigeria is figure out ways to steal from the oil wealth that nature put in our soil but cannot generate wealth by ourselves. Take Nigerians out of my face before I vomit!

Anyway, as my life progressed, I decided that I am not a follower of other people's religions and philosophies and decided to understand what God and existence means to me.

Over time, I learned that whereas there seems no meaning in our earthly lives that there is meaning in our spiritual life.  There is God. I know that for sure, for I have experienced God (and seen Jesus Christ on a number of occasions...if I narrate my spiritual experiences it will blow your mind!).

In God, the state of perfect union, we have meaning and grandeur but when we separated from God and began dreaming that we are separated we have no real meaning in our lives. By the way, that is what Gnosticism teaches (see the third century Roman Platonist and Gnostic thinker, Plotinus, his book, The Ennead. Most of the Greek and Roman stoic thinkers, such as Zeno, Cicero, Seneca, Marcus Aureoles, Virgil, Horace, and Epictetus were really Gnostics.

The Gnostic believes that there is God and that he is light and that we are the children of God who left the light of God and entered the world of darkness, the world of the ego; the goal of Gnosticism/ knowledge is to rediscover light and live from that light, which is love. Love is light; hate is darkness.

We must, therefore, return to God to find meaning in our lives. God is love, returning to God means returning to love. No one comes to God who is not a loving person.

Do you want to experience God? Do you want to enter heaven, aka unified state? If so then do what God, via our elder brother, Jesus Christ, asked us to do: love God with all your heart and love all your neighbors as you love yourself. And forgive all the people that wronged you.

Remember that the only prayer that Jesus taught his apostles is on forgiveness, the Lord's prayer:"Our father, who is in heaven...forgive us our sins because we have first forgiven those who sinned against us" This means that if we do not forgive people who sinned against us we will not be forgiven our own sins.

CONCLUSION

Generally, when my brain is stimulated by a question it can go on and on trying to answer it, sometimes in a rambling sort of way, as I have done in this response to you.

I do not know if my answer is what you were expecting but if you read between the lines you will understand what light is; you will also see that your other questions were answered, sort of.

A while ago, I got home from church and decided to respond to your questions; I am carried away talking about all sorts of things that are related to light. Pardon my wordiness; that is who I am; I cannot help myself; I must be myself!

Cheers,

Ozodi Osuji

June 19, 2016

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Ozodi Osuji Ph.D

Ozodi Thomas Osuji is from Imo State, Nigeria. He obtained his PhD from UCLA. He taught at a couple of Universities and decided to go back to school and study psychology. Thereafter, he worked in the mental health field and was the Executive Director of two mental health agencies. He subsequently left the mental health environment with the goal of being less influenced by others perspectives, so as to be able to think for himself and synthesize Western, Asian and African perspectives on phenomena. Dr Osuji’s goal is to provide us with a unique perspective, one that is not strictly Western or African but a synthesis of both. Dr Osuji teaches, writes and consults on leadership, management, politics, psychology and religions. Dr Osuji is married and has three children; he lives at Anchorage, Alaska, USA.

He can be reached at: ozodiosuji@gmail.com (907) 310-8176