For millennia before clocks, our only regular way of measuring time had been the alternation of day and night. The rhythm of day followed by night also regulates the lives of plants and animals. Diurnal rhythms are ubiquitous in the natural world. They are essential to life, and it seems to me probable that they played a key role in the very origin of life on Earth, since an oscillation is required to set a mechanism in motion. Living organisms are full of clocks of various kinds—molecular, neuronal, chemical, hormonal—each of them more or less in tune with the others. There are chemical mechanisms that keep to a twenty-four-hour rhythm even in the biochemistry of single cells.

Aristotle is the first we are aware of to have asked himself the question “What is time?,” and he came to the following conclusion: time is the measurement of change. Things change continually. We call “time” the measurement, the counting of this change.

So if nothing changes, if nothing moves, does time therefore cease to pass?

Aristotle believed that it did. If nothing changes, time does not pass — because time is our way of situating ourselves in relation to the changing of things: the placing of ourselves in relation to the counting of days. Time is the measure of change: if nothing changes, there is no time.

The time measured by a clock is “quantified,” that is to say, it acquires only certain values and not others. It is as if time were granular rather than continuous.

The “quantization” of time implies that almost all values of time t do not exist. If we could measure the duration of an interval with the most precise clock imaginable, we should find that the time measured takes only certain discrete, special values. It is not possible to think of duration as continuous. We must think of it as discontinuous: not as something that flows uniformly but as something that in a certain sense jumps, kangaroo-like, from one value to another.

In other words, a minimum interval of time exists. Below this, the notion of time does not exist—even in its most basic meaning.

I'm always trying to use my unconscious as much as possible in order to avoid extra labor. I think one of the great [mumble] about people is whether they've learned to use their unconscious to solve problems.  I use it every day.

I review all the things I'm working on just before I go to sleep, and when I wake up in the morning I do not open my eyes, I lie there and recall what I was working on.  And about one time in three there is an idea there - for free - and it almost always works!  And it's been produced by your unconscious, which has still been working while you were asleep.

We evolved with an unconscious.  Why?  Why did we evolve with an unconscious mind?

Barium (Ba) has a radius of 0.253 nanometers (253 picometers)
Strontium (Sr) has a radius of 0.215 nanometers (215 picometers)
Calcium (Ca) has a radius of 0.197 nanometers (197 picometers)
Sodium (Na) has a radius of 0.190 nanometers (190 picometers)
Lithium (Li) has a radius of 0.167 nanometers (167 picometers)
Silver (Ag) has a radius of 0.165 nanometers (165 picometers)
Copper (Cu) has a radius of 0.145 nanometers (145 picometers)

During the fall from high energy to normal energy, the electron emits a photon -- a packet of energy -- with very specific characteristics. The photon has a frequency, or color, that exactly matches the distance the electron falls.

You can see this phenomenon quite clearly in gas-discharge lamps. Fluorescent lamps, neon signs and sodium-vapor lamps are common examples of this kind of electric lighting, which passes an electric current through a gas to make the gas emit light. The colors of gas-discharge lamps vary widely depending on the identity of the gas and the construction of the lamp.

Sodium $\text{Na}$ produces yellow color,
Copper $\text{Cu}$ gives blue.
Barium $\text{Ba}$ emits green and
Strontium salts and lithium salts produce:
Lithium carbonate, ${\text{Li}}_2{\text{CO}}_3$ emits red
Strontium carbonate, ${\text{SrCO}}_3$ emits bright red.

I’m pretty sure there is no possible answer to that question. A photon is a wave — usually a wave packet, which limits and fuzzily defines its net “length”, but it can occupy any number of different volumes and still be the same quantum.

What is the size or volume of a shout?

Physicists had known for nearly three decades that something was wrong, that a change was desperately needed to understand what was happening in the world of the very small—the world of atoms. But they were working blind. Atoms are simply too small to see through any normal microscope, no matter the magnification. The wavelength of visible light is thousands of times larger than the size of an individual atom.

Despite the fact that every physicist agrees that quantum physics works, a bitter debate has raged over its meaning for the past ninety years, since the theory was first developed. And one position in that debate—held by the majority of physicists and purportedly by Bohr—has continually denied the very terms of the debate itself. These physicists claim that it is somehow inappropriate or unscientific to ask what is going on in the quantum realm, despite the phenomenal success of the theory. To them, the theory needs no interpretation, because the things that the theory describes aren’t truly real. Indeed, the strangeness of quantum phenomena has led some prominent physicists to state flatly that there is no alternative, that quantum physics proves that small objects simply do not exist in the same objectively real way as the objects in our everyday lives do. Therefore, they claim, it is impossible to talk about reality in quantum physics. There is not, nor could there be, any story of the world that goes along with the theory.

The popularity of this attitude to quantum physics is surprising. Physics is about the world around us. It aims to understand the fundamental constituents of the universe and how they behave. Many physicists are driven to enter the field out of a desire to understand the most basic properties of nature, to see how the puzzle fits together. Yet, when it comes to quantum physics, the majority of physicists are perfectly willing to abandon this quest and instead merely “shut up and calculate,” in the words of physicist David Mermin. 

This is an astonishing state of affairs, and hardly anyone outside of physics knows about it. But why should anyone else care? After all, quantum physics certainly works. For that matter, why should physicists care? Their mathematics makes accurate predictions; isn’t that enough? 

“I think I can safely say that nobody understands quantum mechanics.”

In case we didn’t get the point, Feynman drove it home in his artful Everyman style. ‘I was born not understanding quantum mechanics,’ he exclaimed merrily, ‘[and] I still don’t understand quantum mechanics!’ Here was the man who had just been anointed one of the foremost experts on the topic, declaring his ignorance of it.

Feynman’s much-quoted words help to seal the reputation of quantum mechanics as one of the most obscure and difficult subjects in all of science. Quantum mechanics has become symbolic of ‘impenetrable science’, in the same way that the name of Albert Einstein (who played a key role in its inception) acts as shorthand for scientific genius.

Feynman clearly didn’t mean that he couldn’t do quantum theory. He meant that this was all he could do. He could work through the math just fine – he invented some of it, after all. That wasn’t the problem. Sure, there’s no point in pretending that the math is easy, and if you never got on with numbers then a career in quantum mechanics isn’t for you. But neither, in that case, would be a career in fluid mechanics, population dynamics, or economics, which are equally inscrutable to the numerically challenged.

No, the equations aren’t why quantum mechanics is perceived to be so hard. It’s the ideas. We just can’t get our heads around them. Neither could Richard Feynman. His failure, Feynman admitted, was to understand what the math was saying. It provided numbers: predictions of quantities that could be tested against experiments, and which invariably survived those tests. But Feynman couldn’t figure out what these numbers and equations were really about: what they said about the ‘real world’.

 

Robert Heinlein is the legendary author of such classic works as Starship Troopers, The Moon Is a Harsh Mistress, and Stranger in a Strange Land. His books have influenced generations of artists and scientists, including physicist and science fiction writer Gregory Benford.

“He was one of the people who propelled me forward to go into the sciences,” Benford says in Episode 348 of the Geek’s Guide to the Galaxy podcast. “Because his depiction of the prospect of the future of science, engineering—everything—was so enticing. He was my favorite science fiction writer.”

 

    

The mechanism by which a light wave is transported through a medium occurs in a manner that is similar to the way that any other wave is transported - by particle-to-particle interaction.    

Particles can pass though objects. For example, right now there are 100 billion solar neutrinos per second passing through every square centimeter of your body. The neutrinos are particles that only have VERY weak interactions with the matter that our bodies are made of so almost all of them pass through without interacting. So, in general, there is no problem with particles passing through matter if they do not interact with the matter - there is lots of space between the nuclei of atoms.

The separation between atoms in glass is measured in picometers. The wavelength of visible light is measured in nanometers. That should tell you something. Yep. The wavelength of that passing electric field disturbance covers hundreds if not thousands of atoms. Think about that when you start to talk about “interactions”.

When light falls on glass, the photons are absorbed by the electrons of the atoms on the surface of glass. But then then almost immediately these electrons transmit this photon by giving out the same energy it had previously absorbed and returns to the ground state.

With a series of these absorption-transmission steps, the light photons exit on the other side of the glass. 

Light (photons) actually pass through a-lot of things. Air for instance. In fact there is one and only one thing in the entire universe that can stop a light wave or particle. Without this one thing a photon will fly off to the edge of the universe and/or a black hole, whichever happens first. You are bathed daily in ancient photons born at the universe’s creation.

Intrigued? Ready? The only thing “powerful” enough to stop [absorb] a light beam is a charged particle. In everyday practical terms this will be an electron. Further not every electron will do, the electron needs to be “special” in that it is in a special state that allows it to effect the photon. Specifically: the photon’s energy [i.e. the light’s color] must be within the range of energy that the electron is allowed to absorb. This range is governed by the wacky laws of quantum theory.

White light is composed of all the visible colors in the electromagnetic spectrum, a fact that can be easily proven through the use of a prism. As light passes through a prism, it is bent, or refracted, by the angles and plane faces of the prism and each wavelength of light is refracted by a slightly different amount. Violet has the highest frequency and is refracted the most. Red has the lowest frequency and is refracted the least. Because each color is refracted differently, each bends at a different angle, resulting in a fanning out and separation of white light into the colors of the spectrum.

The explanation for the colours separating out is that the light is made of waves. Red light has a longer wavelength than violet light. The refractive index for red light in glass is slightly different than for violet light. Violet light slows down even more than red light, so it is refracted at a slightly greater angle.

The amount of refraction increases as the wavelength of light decreases. Shorter wavelengths of light (violet and blue) are slowed more and consequently experience more bending than do the longer wavelengths (orange and red).

Throughout his first year at Trump’s side, Pence would be a constant, attentive presence who generally spoke only when the president requested it. For weeks at a time, he seemed to have just one major public assignment: admiring Donald Trump. He performed this duty consistently despite the fact that the bellicose and chaotic Trump—he of the infamous “grab ’em by the pussy” videotape—was so personally objectionable that Pence had considered trying to replace him at the top of the ticket as the 2016 election neared. 3 (A Pence aide denied that he had considered doing that.)

Pence offered about three minutes of impromptu praise in which The Washington Post discovered one expression of gratitude or admiration every twelve seconds. Among them were: “I’m deeply humbled, as your vice president, to be able to be here.” “You’ve restored American credibility on the world stage.” “You’ve unleashed American energy.” “You’ve spurred an optimism in this country that’s setting records.” When Pence concluded his praise, President Trump offered up a verbal pat on the head, saying, “Thank you, Mike. That’s very nice. I appreciate that.” Pence replied, “Thank you, Mr. President, and God bless you.” ⁵ The vice president’s cringeworthy display, broadcast live on television, prompted an avalanche of mockery. The nonpolitical website Dictionary.com used Pence’s remarks in a tweet to illustrate the definition of the word sycophant.

James Carville and Paul Begala once observed that “you never stand so tall as when you stoop to kiss an ass.” If that’s the case, then Mike Pence is a giant among men. ⁶ Lewis’s analysis overlooked a significant signal in the final phrase—“and God bless you”—offered by the vice president when he spoke at the cabinet meeting. Easy to regard as a kind of rhetorical tic, like the “God bless America” that presidents tack on to the end of formal addresses, Pence’s call to the deity reminded conservative Christians that their champion was alert to his duty. In fact, as one of Pence’s closest aides would explain, the vice president actually believed he could bring Trump to Jesus and, like Jesus, he was willing to do whatever was necessary to help save Trump’s soul.

In this way, faith became a substitute for facts and permitted believers to assert their superiority even as they proclaimed their humility. In the same way that President Trump insisted his genes made him better than others, this type of Christian assumed extra insights on an ontological basis: faith, rather than might, makes right. Such a belief permitted the faithful to claim humility in the shadow of God’s grace while also feeling just a little (or a lot) superior to others.    

February 5, 2019 - As I write this comment, I still have 10 minutes left on CD #8 of the 8-CD audio book set I burned for "Storm in a Teacup: The Physics of Everyday Life" by Helen Czerski.  I'm listening to it in my car, so I'll finish it this afternoon when I'm driving either to or back from the gym. (Added note: I finished it on my way home.)

The light rays hitting our retina may have travelled from the Moon or from our fingers, but they have the same effect. A single photon is absorbed by a single opsin molecule, twisting the molecule around to start a chain of dominoes that sends an electronic signal into our control systems. As our thirsty body walks into the kitchen, photons that have bounced off a sink, a tap and a kettle stream into our eyes, and our brain processes that information in the blink of an eye to tell us what to pick up first. If it’s slightly dark in the kitchen, we turn on a lightbulb, releasing a fountain of light waves. They radiate outwards, and as soon as their journey starts they’re being modified by the world, reflected, refracted and absorbed until perhaps our eyes pick up what’s left.

Bohr rejected the existence of quanta for many years. In 1923, he had referred to the "insuperable difficulties" of the lightquantum hypothesis in accounting for interference phenomena and asserted that "the picture ... which lies at the foundation of the hypothesis of lightquanta ... excludes, in principle, the possibility of a rational definition of the conception of a frequency which plays a principal part in this theory."¹¹

  

The theory was eventually refuted on experimental grounds, and, in 1927, Bohr final­ly accepted the photon at the price of espousing complementarity13 and, thus, enshrining the wave-particle duality of light as a permanent feature of the Copenhagen interpretation, a denouement that has been described as "a case in which competing views, found unresolvable, were simply combined-perhaps a singular event in the development of science"¹⁴ and one that it must be said has caused dissension ever since (see, e.g., Park 15).

Maxwell’s theory explains certain experiments well, but the same is true of the photon concept. Do we then have to conclude that light is both a wave and a particle? That would be too bad, since it would not make any sense. But think for a minute: What is a physical experiment and what does it actually tell us? We prepare a piece of apparatus, we turn it on, something happens, a measurement is made. The experiment tells us what happened, and a good theory tells what will happen before any one does the experiment. The crucial point is this: An experiment or a theory tells what happens, not what is.

Experiments in the old days usually involved things one could touch and see, and it is from experience of touching and seeing that we get our firm ideas of what is; therefore, if one deduced what was from what happened, things rarely went wrong. You can see light but you cannot see a light wave; you cannot touch a photon, and it is obvious from the experiments just described that a light wave is not just a scaled-down version of waves in a duck pond, nor is a quantum particle a scaled-down version of a baseball. In fact, the nature of light cannot be represented as a scaled-down version of anything we are familiar with. It has its own nature, whatever that may be, and what we know about it is what happens in different experiments. Luckily for us, the situation is not entirely strange. What happens in some experiments can be modeled by a wave; in others, by a particle. Often, as when we have to deal with the electron cloud surrounding an atom, neither of those models is very helpful in understanding what happens and we trust the model whose root is in mathematics. It may not satisfy all our desires, but at least it works.

"Don't get me wrong, there is nothing wrong with mathematics--it's the language we use to express the precise relations of physical law. But there is an increasing tendency to mistake the language for the physics itself. Once we lose the conceptual foundations, the whole thing becomes a shell game."  

One of the most puzzling features of standard quantum mechanics, especially to undergraduate students, has been the wave-particle duality.  The duality of light, coupled with the corpuscular photon model, has been given many conflicting interpretations and has promoted almost universal confusion among nonexperts.

Elementary survey course textbooks usually leave the impression that the photon is a small, spherical entity along the lines suggested by Lewis and is the ultimate constituent of electric current.

To my mind, Einstein was right to caution us concerning light. Our understanding of it has increased enormously in the 100 years since Planck, but I suspect light will continue to confound us, while simultaneously luring us to inquire ceaselessly into its nature.

Can two photons that have never met know something about each other? 

Photonics is the physical science of light (photon) generation, detection, and manipulation through emission, transmission, modulation, signal processing, switching, amplification, and sensing.

The theories of light are presented at progressively increasing levels of difficulty.  Thus light is described first as rays, then scalar waves, then electromagnetic waves, and, finally, photons.

1. Ray Optics
2. Wave Optics
3. Beam Optics
4. Fourier Optics
5. Electromagnetic Optics
6. Polarization and Crystal Optics
7. Guided Wave Optics
8. Fiber Optics
9. Resonator Optics
10. Statistical Optics
11. Photon Optics
12. Photons and Atoms
13. Laser Amplifiers
14. Lasers
15. Photons in Semiconductors
16. Semiconductor Photon Sources
17. Semiconductor Photon Detectors
18. Electro-optics
19. Nonlinear Optics
20. Acousto-optics
21. Photonic Switching and Computing
22. Fiber-Optic Communications

Light consists of particles called photons.  A photon has zero rest mass and carries electromagnetic energy and momentum.  It also carries an intrinsic angular momentum (or spin) that governs its polarization properties.  The photon travels at the speed of light in a vacuum (c₀); its speed is retarded in matter.  Photons also have a wavelike character that determines their localization properties in space and the rules by which they interfere and diffract.

Scientists have observed that light energy can behave like a wave as it moves through space, or it can behave like a discrete particle with a discrete amount of energy (quantum) that can be absorbed and emitted. As we study and use light, both models are helpful.

Concept of a photon
The particle-like nature of light is modeled with photons. A photon has no mass and no charge. It is a carrier of electromagnetic energy and interacts with other discrete particles (e.g., electrons, atoms, and molecules).
A beam of light is modeled as a stream of photons, each carrying a well-defined energy that is dependent upon the wavelength of the light.

Photonics is the physical science of light generation, detection, and manipulation through emission, transmission, modulation, signal processing, switching, amplification, and sensing, in which photon models are used when the particle properties of light can be accurately modeled using mathematics, and wave models of light are used when the wavelike properties of light can be accurately modeled using mathematics.  No one has any idea how light really works.

there's no difference to a light wave that runs forward or backward in time.

Francois Copie, scientist on the project explains: "When seeding the ring resonator with short pulses, the circulating pulses within the resonator will either arrive before or after the seed pulse but never at the same time."

Light waves wiggle perpendicular to the direction of their movement, just like a plucked string. The orientation of this wiggle is called its polarisation, and whether we're talking guitar strings or light waves, it tends to remain fixed as the wave moves.

Not so here. As the wave toured around the optical fibre, its orientation described a corkscrew 'elliptical' shape, breaking its usual rule of sticking to a single plane.

All that seems to indicate is that when light photons are forced to change their direction of travel inside an optical fiber, they change their orientation.  That probably means that, regardless of its orientation when it entered an optical fiber, a photon will be horizontally oriented when it comes back out. 

Or the forces that cause the photons to change directions as the photons are forced to travel in circles also cause the photons inside the fibers to travel in a corkscrew pattern - possibly as a result of outside forces (like gravity) affecting what happens inside a fiber.

Dammit!!  Life would be so much simpler if physicists just stopped writing about light as if it consisted of waves.  It doesn't.  It consists of photons.  And photons do not "wiggle perpendicular to the direction of their movement."  They are disk shaped, and the disks are oriented perpendicular to their direction of movement.  The up and down motion that physicists fantasize as waves is just the difference in the shape of a disk as it arrives traveling edge-on.  It starts as a dot, then gets bigger and bigger, and then gets small and smaller until it is a dot again. Then there is nothing, and you have to wait for the next photon to arrive.

Here's an image I created a couple days ago to show how disks set up end to end can be viewed as producing a wave pattern:



Light waves do not arrive end to end.  And neither do photons.  But if you lack imagination and idiotically insist on viewing light as consisting of waves, then you simply fantasize that light waves arrive end to end. 

Physics would be so much simpler if light was viewed as individual photons without any of the imaginary fantasies that make light seem like waves!   

January 29, 2019 - I spent all day yesterday working on a scientific paper about "The Importance of Understanding Photons."  Writing such a paper would probably be a lot easier if I understood photons.  I'm hoping that writing the paper will help me with that understanding.  I'm going through what is known about photons step by step to see where it leads me.

The problem is, I cannot make sense of many of the articles I'm reading as I do my research.  The process of polarization is almost always shown this way:
 

The polarizers illustrated above are actually filters containing long-chain polymer molecules that are oriented in a single direction. Only the incident light that is vibrating in the same plane as the oriented polymer molecules is absorbed, while light vibrating at right angles to the plane is passed through the first polarizing filter. In Figure 1, polarizer 1 is oriented vertically to the incident beam so it will pass only the waves that are vertical in the incident beam. The wave passing through polarizer 1 is subsequently blocked by polarizer 2 because the second polarizer is oriented horizontally with respect to the electric field vector in the light wave.

The polarizers illustrated above are actually filters containing long-chain polymer molecules that are oriented in a single direction. 

     

   

According to quantum mechanics, electromagnetic waves can also be viewed as streams of particles called photons. When viewed in this way, the polarization of an electromagnetic wave is determined by a quantum mechanical property of photons called their spin^{[citation needed]}. A photon has one of two possible spins: it can either spin in a right hand sense or a left hand sense about its direction of travel. Circularly polarized electromagnetic waves are composed of photons with only one type of spin, either right- or left-hand. Linearly polarized waves consist of equal numbers of right and left hand spinning photons, with their phase synchronized so they superpose to give oscillation in a plane.

Linearly polarized waves consist of equal numbers of right and left hand spinning photons, with their phase synchronized so they superpose to give oscillation in a plane.      

We were making a jump of about eighty-five light-years—at such a hair-raising fraction of c that the trip would seem to us to take twenty years, total. But back in the normal universe, clocks run faster, thanks to Dr. Einstein’s Paradox. To an observer at, say, Tombaugh Station around Pluto, our voyage would appear to take roughly ninety and one-half Standard years.      

By that point in our voyage, six months out, we were already beginning to use Dr. Einstein’s Clock instead of Sol.  [I.e., ship-board clocks instead of the Sun.] Lorentz contraction had set in, and we were aging just measurably slower than the people we had left behind.

How much slower? Not a lot—yet. At the instant when those of us in the Sheffield passed the six-month mark of the trip, residents of the Solar System were only about seventeen and a half hours older than we were.

But it would get steadily worse as our velocity mounted up. And constant boost mounts up fast.

At the one-year mark, the differential would be about seven days and seven hours.

At two years, it would be more than fifty-eight days.

By the five-year mark, the divergence of our clocks and mankind’s would surge up to almost three years. We would be traveling at more than 0.938c.

And when I had been traveling for ten years, and was twenty-eight years old, more than forty-five years would have elapsed on Terra. Behind me Jinny would be closing in on sixty-four.

And receding at 99.794 percent of the speed of light.

During this period, Tesla spoke out vehemently against the new theories of Albert Einstein, insisting that energy is not contained in matter, but in the space between the particles of an atom.
—Tesla, Master of Lightning PBS-TV documentary, Dec. 12, 2000

And just as with modern-day black holes, floating around in space, the laws of nature dictate something quite extraordinary. They tell us that here too time itself must come to a stop. You can’t get to a time before the Big Bang because there was no time before the Big Bang. We have finally found something that doesn’t have a cause, because there was no time for a cause to exist in. For me this means that there is no possibility of a creator, because there is no time for a creator to have existed in.

Most people respond to a qualitative, rather than a quantitative, understanding, without the need for complicated equations.

My calculations predicted that a black hole creates and emits particles and radiation, just as if it were an ordinary hot body, with a temperature that is proportional to the surface gravity and inversely proportional to the mass. This made the problematic suggestion of Jacob Bekenstein, that a black hole had a finite entropy, fully consistent, since it implied that a black hole could be in thermal equilibrium at some finite temperature other than zero. Since that time, the mathematical evidence that black holes emit thermal radiation has been confirmed by a number of other people with various different approaches.    

I believe the future of learning and education is the internet. People can answer back and interact. In a way, the internet connects us all together like the neurons in a giant brain. And with such an IQ, what cannot we be capable of?

Aggression, in the form of subjugating or killing other men and taking their women and food, has had definite survival advantage up to the present time. But now it could destroy the entire human race and much of the rest of life on Earth.

Why are we so worried about artificial intelligence? Surely humans are always able to pull the plug? People asked a computer, “Is there a God?” And the computer said, “There is now,” and fused the plug.

The Earth is becoming too small for us. Our physical resources are being drained at an alarming rate. Mankind has presented our planet with the disastrous gifts of climate change, pollution, rising temperatures, reduction of the polar ice caps, deforestation and decimation of animal species. Our population, too, is increasing at an alarming rate. Faced with these figures, it is clear this near-exponential population growth cannot continue into the next millennium.

It is now closer to Doomsday than at any time since then, save in the early 1950s at the start of the Cold War. The clock and its movements are, of course, entirely symbolic but I feel compelled to point out that such an alarming warning from other scientists, prompted at least in part by the election of Donald Trump, must be taken seriously.

Forty years on, our most intrepid explorer, Voyager, has just made it to interstellar space. Its speed, eleven miles a second, means it would take about 70,000 years to reach Alpha Centauri. This constellation is 4.37 light years away, twenty-five trillion miles. If there are beings alive on Alpha Centauri today, they remain blissfully ignorant of the rise of Donald Trump.

Unfortunately, we cannot go back in time. With Brexit and Trump now exerting new forces in relation to immigration and the development of education, we are witnessing a global revolt against experts, which includes scientists.

“When I think I’m right, nothing bothers me.” - Donald Trump

PART I: Callahan's Crosstime Saloon                                        1
PART II: From Time Travelers Strictly Cash                          153 
PART III: Callahan's Secret                                                    227

This one night in particular had used up an awful lot of alcohol, and one hell of a lot of spiritual fortitude. The topic was one of those naturals that can be milked for hours: “electricity.” It was about one-fifteen that the trouble started.

By this point in a harrowing evening, the competition was down to the Doc, Noah Gonzalez and me. I was feeling decidedly pun-chy.

“I have a feeling this is going to be a good round Fermi,” the Doc mused, and sent a few ounces of Scotch past an angelic smile.

“You’ve galvanized us all once again, Doc,” said Noah immediately.

“Socket to me,” I agreed enthusiastically.     

About 50 percent of the people responding said the answer was zero.  About 30 percent said the answer was 200 N (Newtons).  The remaining 20 percent said the answer was 100 N.  Most people didn't explain their reasoning.  The first person to claim the answer was zero and give his reasoning was obviously a mathematician, since he stated:

The two forces are in opposite direction.which gives the total force,f,as f1-f2=200-200=0N

The first person to claim the answer was 200 N and give his reasoning explained:

200 N cause the weight on the right further pulls the scale apart.

The first two people who claimed the answer was 100 N and who also provided explanations wrote:

Sridhar Ambati Its 100..u can imagine a situation where spring blance is hung vertically with 100N weight. the rigid support which is attached to the hook will offer 100N reaction force. But spring balnce will show only 100N

Mohamed Ahmed 100 N, one mass acts as a support and the scale only reads the weight of the other one. This situation is similar to mass hanging vertically from a spring attached to a scale hanging on the wall.

I agreed that 100 N is the right answer, but I thought a longer and clearer explanation was needed, so I wrote:

The answer is 100 N, but the problem is describing WHY it is 100 N.

It is 100 N because gravity is being measured, and you cannot measure gravity unless you have something to measure gravity against.

If the scale was nailed to the table, only the weight on the left side would be measured. It is the one pulling on the hook that measures weight.

In the illustration, the weight on the right takes the place of the nail. It holds the scale in place while the scale weighs the weight on the left.

If you added a gram to the weight on the left, the gram would pull the scale over to rest against the pulley, and the scale would measure 100 N and 1 gram. Add a gram to the weight on the right, and the scale would still show 1 N plus 1 gram, but you would be able to position the scale back in the center of the table again.

The only way the scale would measure 200 N is if the scale was nailed to the underside of the table and both weights were hanging from the hook.

The only way the scale would measure zero is if it had hooks on both ends and zero was in the center of the scale.

I immediately started getting people "liking" my post.  But I felt I needed to explain further.  I also felt that the illustrated question needed to have some scale readings.  So, I created this version of the question:

And I wrote,

The question still is: Why would the scale register zero or 200 N?

That got an immediate response that I put the zero on the wrong end of the scale.  And then someone else complained that I should use more numbers and not put 100 N in the middle, because that would make some people think equal weights would give the middle number.

They were both right.  So, I created this version of the illustrated question:

And I wrote this:

Here's a new version of the illustration. The question is: What will the scale show? zero, 100 N or 200 N?

The question is NOT how much weight is the table holding up. That would be 200 N plus the weight of the scale, ropes and pulleys.

The question is NOT whether the weight on the left side is equal to the weight on the right side. Obviously it is.

The scale will show 100 N.

The scale would show 200 N if the scale was nailed to the table and both weights were hanging from the hook on the scale. But that isn't what the illustration shows.

The scale CANNOT show zero, since it is obviously holding up some weight.

The scale shows 100 N because the 100 N on the right side is keeping the 100 N on the left side from falling to the floor and taking the scale with it.

It takes 100 N of lift to keep 100 N from falling. The scale just measures the lift required to overcome gravity and keep the weight from falling.

My explanation didn't stop the debate.  They are still arguing.  There were at least 37 posts overnight, and most of them are just posting answers without explanations.  And one person is posting a video over and over, at least ten times so far.  Here's the video:

The video shows the experiment being performed in a classroom, and it shows the answer would be 100 N.  (In the video, the teacher uses 10 N weights.) (You can view part 1 of the lesson HERE and part 2 HERE.)

I also see one responder in the thread complaining that the answers should just be a number without any explanation, because no one has time to read long explanations.  His comment is in response to a multiple part, long winded answer that doesn't say whether the answer is zero, 100 N or 200 N.

In response to my answer and final illustration, I had a conversation with someone named "James Quick" that went like this:

QUICK: I have a problem trying to figure out why so many people are having a problem with basic physics I mean BASIC !

LAKE: That's a psychology question. My answer would be that some people think logically with the left side of their brain while others think visually and emotionally with the right side of their brain. The weights in the illustration LOOK equal, so they seem to balance each other out. The two weights are both pulling on the scale, so they LOOK like the scale should weigh them both.

You need to know how gravity works and how it is measured to understand the logic of the problem. To measure gravity you need to pull AGAINST something. The left weight is pulling against the scale which is held in place by the right weight.

QUICK: That being said, this is a physics group right?

LAKE: Right, it's a physics group. But people who are interested in physics do not always think logically. Many physics students are taught to think mathematically. They claim that mathematics IS logic or that logic can be replaced by mathematics. If you try to get them to explain something, they can only explain with mathematical equations. They only understand math. What is actually PHYSICALLY happening is of absolutely no interest to them.

The illustration looks like a mathematical equation with equal weights on both sides. So, mathematically, the answer should be zero.

QUICK: So if you're a physicist you have to abandon all logic? 

LAKE: They don't think that way. They just think about the math and don't think about the logic. They also believe that "cause and effect" is no longer part of physics. Physics is just math. Period. If you argue logic with them, they just think you are stupid because you aren't phrasing things in mathematical terms.

Quick responded to that last post by just indicating that he "liked" my answer.  That was the end of the discussion except for a post by someone who I assume is a mathematician, since he wrote:

Mahima Romanoff: Remember there questions come with important info like--"weight of strings, pulleys, and spring is 0". The whole concept of these type of questions is the equilibrium. The only way this will work is if the pointer scale null is in the middle of the scale. Suppose the distance between 0 and 100N is 'x' and distance from middle of scale to weights is 'y' then , the left side length is y+x while the right side length is 'y'. Whoa.

Your math is blowing my mind. 

After that, the thread is just more arguing between other people, plus a lot of people just giving their answers in the form of a number.  As of this moment, there are 167 posts and 126 individuals have indicated that they like, love or are amazed by the thread.  I just added my name as someone loving the thread. 

I think I might create a version of it for my Facebook group on Time and Time Dilation.  It would be off topic, but it's my group, so I can break the rules if I have a good reason.  I might also start a thread about "What is a Photon?"  Maybe someone will give me an idea that will get me going on writing about that subject again.