Time!

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The Standard of Ur (c. 2,600 BCE). British Museum, London.

 

Beneath the touch of Time’s unerring hand,

Like priceless treasures sinking in the sand.

–Claude McKay,  “America”

(i) Who is the oldest person you can think of? Dead or alive. It’s not necessary to have known the person, but you do have to know some facts about their life. Also, their name. So he’s out.

I imagine that the major religious traditions provide the most obvious choices. Whether apocryphal, quasi-apocryphal, or somewhat historical, figures from the Hebrew and Christian Bible loom large in the collective imagination of deep history. Hellenic sources provide even older and fantastic documentation as do the truly ancient mythic and historical personages figures from the Near East.

I’m going to go with the Buddha himself since his case is illustrative of my point. He lived sometime around the 5th century BCE, so 2,500 years ago. He was a noble, the son of monarchs, who resided somewhere in what is now Northern India or Nepal. He lived an isolated life of luxury inside the palace, shielded from the strife and suffering of the outside world. At age 29 he saw a visibly old man for the first time and it naturally blew his mind. His charioteer let him know that aging and decline eventually happened to everyone, which prompted the prince to travel outside the palace gates (to the town marketplace? to the surrounding villages?) where he encountered further disturbing truths about the human condition.

Cone
Female cone from a giant sequoia, the largest and one of the longest-lived species on Earth.

 

I like Siddhartha Gautama’s origin story, because like so many of the biographical sketches from antiquity, the world-building details are conventional and intuitive for the modern reader. Like a fairy tale or Disney film. You have a king and queen and a palace. There are peasants, craftspeople, and soldiers. There are laws. People use money in markets or in local places of drink and leisure. War and the threat of war are constant preoccupations along with rumination on relationship between humans, God, and the representatives of the divine on Earth.

It’s almost universal. Whether the setting is Medieval, Classical, Biblical, or The East™ these common tropes of ancient life are inextricable from our notions of “the past.” This is what we might call the assumption of civilization. That is, our imagination of antiquity reveals a world not unlike our own. But it hasn’t always been this way.

Timeline
Timelines depicting (top) the last five million years and (bottom) the last two-hundred thousand years. All recorded history is indicated within a tiny portion of the second line.

Human beings have been around for 200-100 thousand years or so. It is only within the last 12,000 that we have evidence of prolonged sedentism and domestication. The trappings of “civilization” including living in cities, hereditary monarchy, economic classes, complex division of labor, metal working, writing, etc. only have been around for 5,000 years. While the first process happened globally during the transition from the climatically volatile Pleistocene to the relatively mild Holocene, the second phenomenon arose independently only in six places, eventually spreading from these locations.

Civs
The six cradles of civilization shown in the western and eastern hemisphere.

To my mind, these are the two most important questions in the field of human prehistory. The first: how did we go from more than 100,000 years of relatively small-scale, mobile societies to a global florescence of large settlements, with institutionalized leadership, craft production, monumental architecture, and agriculture? The second: why did urbanism, social stratification, and what we envision as “the ancient world” emerge only in a few places almost 10,000 years afterward?

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Jade figurines depicting elite individuals. Wari civilization, Peru (c. 500-1,000 CE). Museo de America, Madrid.

(ii) Archaeology, paleontology, and cosmology are historical sciences. The data are the artifacts of long concluded events and processes. These must be reconstructed through an understanding of the taphonomic distortions of time and space.

The early universe was very dense and very hot. The fundamental constituents of atoms (protons and electrons) existed in a highly energetic state that made it impossible for them to bond to form stable atoms. This thick plasma (another name for ionized matter) soup was opaque due to the inability of photons to travel very far before encountering and being deflected by free electrons.

Then, just 378,000 years after the Big Bang, the universe cooled enough for the protons and electrons to bond and form stable atoms. At this point, the universe became transparent, allowing for photons to pass through unimpeded. The cosmic microwave background (CMB) is what remains of the very first light to transverse the cosmos. Its existence was in fact predicted before it was discovered as a consequence of the Big Bang Theory.

CMB
The opaque horizon of the CMB is always receding as the liberated photons are always arriving.

The opacity to clarity process described above happened everywhere at the same time in what is believed to be an infinite, isotropic universe. The light which was liberated at this time, therefore, exists literally everywhere. At every location in the universe, light which has traveled for time = age of the universe – 378,000 years is always just now arriving. If we think of a particular location such as our planet, we can also imagine an impenetrable, every-receding, spherical, plasma horizon surrounding us.

(iii) Music works because our minds perceive a given pitch (n) that can be related to other pitches through the operation ([n],[2n],[4n],[8n], etc.; or [[[n]*2]*2]*2, etc.) as sounding the same. Pitches whose ratios have smaller denominators sound better when heard together (more consonant) than pitches with larger ratios (more dissonant). For the examples below, my starting pitch (the tonic) is A4 or 440 Hz. This is a matter of convention, since musical scales can be based on any pitch. Remember, that wave length and frequency are proportional.

 

Notes
The tonic (A4) indicated in blue as a sine wave and below as a key on the piano compared with notes at relatively consonant intervals including the octave (A5) in red.

A4 (blue) on a piano plays a note which resonates principally at 440 Hz (though overtones exist which give the piano its characteristic sound (or timbre)). A5 (red) is the octave of A4. They are the same note meaning they sound the same to our ears aside from the fact that one is higher and one is lower. The ratio of A5:A4 is 2:1. The next most consonant interval is the fifth, which in the example is the key E5 marked in green. The ratio between A4 and E5 is 3:2. Notice that the sine wave depicted in green intersects the octave point where blue and red converge. For comparison I have included some other relatively consonant intervals including the fourth (white – 4:3), the major third (yellow – 5:4), and the minor third (brown – 6:5).

HzNotes
Graph depicting pitch ratio (in comparison to the tonic A4) and frequency in Hz. The size of the circle for each note in the octave illustrates the degree of dissonance with the tonic.

 

(iv) All living organisms share a common ancestor deep in the past. One of the tasks of biology is the elucidation of evolutionary relationships through the construction of phylogenic trees which relate extant species through their descent from extinct common ancestors. The resulting cladograms typically depict species as branches and putative ancestors as nodes.

Reptiles
Simplified phylogeny showing the evolutionary relationship between birds + dinosaurs, crocodilians, and other reptiles. Three monophyletic groups exist, including the avian and non-avian dinosaurs, the descendants of the common ancestor at the blue node, and all of the groups together  (the descendants of the common ancestor at the red node).

Groups which include a common ancestor and all of its descendants are known as clades or monophyletic groups. These are “natural” biological categories which have evolutionary significance. Interesting cases arise when our colloquial or conventional categories do not map onto the evolutionary reality. One such category is the artificial group, “reptile.” When we think of reptiles, we think of lizard, snakes, crocodiles, and dinosaurs. We typically do not think of birds as reptiles. However, birds (which are a subgroup of dinosaurs, avian dinosaurs) are more closely related to crocodiles and alligators than either group is to the snakes and lizards of the world. Therefore, either birds are reptiles or the word “reptile” has no biological significance as a category.

Personally, I like to think of birds as an interesting group of reptiles which have evolved unique characteristics, including flight, endothermy, and fuzziness (feathers). “Unique” is perhaps inaccurate as other dinosaur groups shared certain of these characteristics as did the more distantly related flying reptiles, pterosaurs, which were also furry, also flew, and likely were also warm-blooded.

FYI: the distinctions between frog and toad as well as turtle and tortoise also carry no biological significance and instead refer colloquially (loosely) to behavior/habitat. And finally, “tree” is not a phylogenic category as it conventionally describes a form which has evolved in different species of plants across many, distantly related clades.

(v) DID YOU KNOW…

The last living T. Rex (~65mya) lived closer to the present day (0mya) than the last living Stegosaurus (~150mya). Dinosaurs were around a long time.

Cleopatra (69-30 BCE) lived closer to the present day (2018 CE) than the construction of the Great Pyramid of Giza (2,500 BCE). Ancient Egypt was around a long time.

(vi) Somewhat unrelated, but timely and on my mind. Which way forward?

The weapon of criticism cannot, of course, replace criticism by weapons, material force must be overthrown by material force

-Karl Marx, “A Contribution to the Critique of Hegel’s Philosophy of Right”

Well, you know
We all want to change the world
But when you talk about destruction
Don’t you know that you can count me out

-John Lennon, “Revolution”

Swan
A swan. A very large bird.
(vii) Time for a bit of a confession/brag.
About a month ago someone posted a video of me on instagram. I didn’t like the way I looked and I decided it was time to get back to a more healthy lifestyle. I almost completely eliminated alcohol, french fries, meal-time “seconds,” and diet soda. I also settled into an intermittent fasting routine wherein I would not eat anything after 8 pm and then not again until 12 pm the following day. This has worked really well for me so far.
Weight
My weight progression for the past thirty-five days. One lesson is not to read too much into what the scale says on any one day. Or better yet, don’t obsessively follow your weight and instead just try to be healthy in a sustainable way.

I have an addictive personality and eating fast food and drinking beer are small comforts which easily become daily habits. I’m not sure how to feel about replacing one addiction (consuming crap) with another (obsessing over what and when I am eating). At the root is surely a disordered relationship with food. I do genuinely believe I feel happier exercising more self-control, a feeling that has some empirical support.

 

(viii) And finally. Sometimes they come easy. Sometimes it’s a struggle. It’s been a struggle.

Vanishingly

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NOT psilocybin mushrooms.

(i) Here’s a fun one: the Boltzmann Brain thought experiment named after Ludwig Boltzmann, the 19th century physicist who first proposed it.

Given the projected lifespan of the entropic universe (plus any and all manifestations of a multiverse) the likelihood that that your brain, in its precise atomic state at the moment you are reading this page, has materialized out of sheer randomness in the middle of a cosmic gas cloud, may be greater than the likelihood that it is the product of a causal set of steps including your life experience, human evolution, the making of this planet, the birth of the sun, etc. IF this is the case, then at this exact moment your brain has winked into existence only to presumably die a moment later, absent life support in the near-vacuum of space. Sound absurd? Of course it does.

It’s an interesting manifestation of what I’ve seen termed Last Thursdayism. The idea being that we have no way of knowing whether what we understand as our past experiences are (a) genuine, (b) the product of random physical fluctuations or (c) the programming of a nefarious demon.

The thing is, I used to be that guy who would proclaim the inevitability of walking through a wall if you had an eternity to attempt it, to wait for the perfect, serendipitous atomic alignment. I’d imagine all of the possible permutations from the faint and unnoticeable to the disastrous (being stuck in the wall). I’d like to think I take a more pragmatic approach now to the question of what is “possible”. If the number of years it would take for something to eventually happen has 1,000 zeros, then it’s safe to say that that something doesn’t actually exist in any real sense. Right? This particular example is also rooted in an erroneous line of thought which imagines the reality of particles in the quantum realm can be extrapolated to the macro reality that we experience.

I remember an instructor of a mineralogy class telling us that systems, which at small scales are chaotic and random, will paradoxically look uniform at large scales. Like the quantum spookiness, the disorder will cancel out at sufficient volume, producing something isotropic from our vantage.

An example is silicon dioxide, commonly encountered as the mineral quartzan oxide made up of one atom of silicon and two atoms of oxygen. These are by far the two most abundant elements in the Earth’s crust. This molecule forms a tetrahedral structure (SiO4) which can exist in crystalline, amorphous or fine-grained (cryptocrystalline or microcrystalline) forms. The most common example is glass, itself, which owes its appearance to a lack of large-scale structural organization.

Quartz
Chert rock with a large embedded quartz crystal. From Santa Cruz island, California.
SiO2
Cartoon depiction of SiOtetrahedral framework. (Do I really have to say it?) NOT to scale.

Flint and chert are brittle rocks with fine-grained, cryptocrystalline molecular structure based on the SiOtetrahedron. They have long been utilized in the manufacture of stone tools due to their conchoidal fracture, that is, fracture that does not occur along cleavage planes, allowing for sharp edges and greater control over the shape of the final product. The distinct fracture creates rippling shock waves, visible in the material, useful for distinguishing between naturally broken rocks and cultural artifacts.

Flint is also associated with fire-making, though it’s not actually the flint that is important. Rather, flint is a very hard rock, allowing it to be used to scrape off small pieces of iron from a steel knife or other iron implement. It is the exposed, high-surface-area iron flakes which have the ability to spontaneously ignite.

(ii) Right around the time you learn that atoms are very small, you also learn that atoms are mostly empty space and that the mass of an electron is 1/1837 the mass of a proton. I was misled for a long time by that final point into believing that electrons were in some sense smaller than protons or the nucleus itself. Ask anyone to draw an atom and you will undoubtedly see a big circle in the middle surrounded by smaller dots on the periphery. This conception of subatomic size leads directly to errant characterizations of the atom as a miniature solar system with electron planets orbiting the nuclear sun: “if positive and negative charges attract, why don’t the electrons crash into the nucleus!?”

Atoms
A cartoon version of two hydrogen atoms depicting small nuceli surrounded by a large electron cloud. NOT AT ALL to scale. In reality, the nucleus is 1/100,000th the size of the atom itself.

But what does “size” actually mean at subatomic scales. I won’t pretend here to understand the subtleties of quantum mathematics, but suffice it to say, that very, very small particles have the peculiar property of also behaving like waves, thus limiting the utility of intuitions that derive extreme differences in volume from extreme differences in mass. As far as these concepts do apply, it makes more sense to think of the massive nucleus as very small and the less massive electron as large given their area of effect.

On a related note, a few years ago a conversation with a relative (something about cosmology) sparked a tangent about the importance of orders of magnitude when making comparisons related to size. For my part, I was enlightened on this logic by a comment on r/askscience (which you should be regularly visiting if you are not already).

When someone asks: are we (humans) closer to the size of an atom or closer the size of the galaxy, what does that imply? For an easier comparison, consider the more intuitive case: is a cat closer to the size of an atom or the size of a tree?

Magnitude
Size comparisons based on absolute measurement in meters and orders of magnitude in meters.

Clearly, a cat is closer in size to a tree than an atom. However, if you were to measure each in absolute terms, say in meters, you would actually find that a cat is “closer” in size to the atom. The confusion results from what is implied in the “closer,” that is, an understanding of orders of magnitude. The atom is many times smaller than the cat or the tree regardless of the absolute, cardinal value of the unit of measurement applied to each.

To the original question, the galaxy is approximately 100 light years across which converts to a diameter of approximately 9×1017 meters across. At a scalar comparison, it is clear that we are closer in size to an atom than our galaxy. The galaxy is quite large.

(iii) Cicadas are large insects known for their distinct, shrill call.

Some cicadas spend the majority of their lifespan underground feeding from tree roots, only to emerge as mature, breeding adults every 13 or 17 years. I remember reading about this phenomenon in one of Dawkins’ books, maybe The Blind Watchmaker, in which I recall him arguing the evolutionary advantage of this peculiar life cycle.

[That same book also introduced me to this, which is another mind-blower.]

Cicadas
Cicadas with 13-year and 17-year life cycles compared with competitors on cycles of 10, 8, and 12. From a hypothetical overlapping Year 0 until Year 60, there is no overlap between the cicadas and the other species.

The logic is as follows: in a world of competitor and predator species with varying multi-year life cycles, there is an advantage to periodicity based on a prime number due to that fact that there will be less chance of overlap in any given year. Of course, this is not the only way to go about being a cicada, as annual versions are common, but as always, there are trade-offs in any evolutionary development.

(iv) Bouvet Island. Love this one. Top-shelf mystery. And this is a brilliant write-up.

I just want to reemphasize the ridiculous isolation of the tiny island and the improbability of things randomly arriving there.

By my own measurements.

To Antarctica: 1,800 km

To Africa: 2,500 km

To South America: 4,200 km

Bouvet
Outlining the vast area of ocean surrounding Bouvet Island. A much smaller circle surrounds the island.

I made a circle around Bouvet Island that touches the coasts of the surrounding continents:

Ocean circle circumference = 19,000 km; radius = 3,024 km; area = 28,728,533 sq. km

Island circle circumference = 35 km; radius = 6 km; area = 113 sq. km

10 million vs. 100; or 5 orders of magnitude greater; or a 1 in 100,00 chance of randomly selecting land instead of ocean (ignoring some of the pesky islands near the continents). Coincidentally, this is also the size of the nucleus of an atom relative to the size of the entire atom! It all ties together!

(v) This one has guitars:

Sound (and vision)

IMG-5208

And now you try
Your handful of notes;
The clear vowels rise like balloons.

–Sylvia Plath, “Morning Song”

(i) Consider Lothar Sieber. On March 1, 1945 he probably became the first human being to travel faster than the speed of sound during the test flight which ultimately claimed his life. This was two years before American Chuck Yeagar became famous for surpassing this benchmark through level flight within a conventional aircraft. Sieber, in contrast, was piloting an experimental German interceptor craft, designed as a manned surface-to-air missile, making him also the first human sent airborne via vertical launch. There’s something distinctly Third Reich in the absurd ambition of this project, the echoes of which led much closer to home.

Sound can be defined as waves of kinetic energy traveling through an elastic, material medium. In most cases, we refer to pressure waves travelling through the air, which is invisible to our eyes, yet composed of diffuse molecules. As an example, when you clap your hands, the vibrations within the solid medium of your palm transmit energy to the surrounding air causing it to move as well. The individual molecules do not move very far; rather, the relatively localized motion causes nearby molecules to bump into molecules a bit further away transmitting energy in a chain reaction. A familiar comparison is the movement of waves in the ocean, where the energy travels through particular regions of water, but the water itself does not move with the wave.

[An interesting alternative case are the wave dynamics at play in traffic jams and spiral galaxies where the individual objects move through relatively static regions of density.]

An object traveling while also producing sound allows for interesting effects in directions toward and away from the motion. An observer listening to an object approaching at sufficient speed will experience an increase in pitch (shorter wave length/higher frequency) because the object is traveling in the direction of wave propagation. If the object increases speed, the time between each subsequent wave will decrease, increasing frequency and decreasing wavelength. The sound waves begin to pile up…

SonicBoom
Between T3 and T4 the character’s speed exceeds the speed of the planes he throws. The stationary bad guy is hit by the paper “sonic boom” at T6.

Imagine a classic run and gun arcade game where the hero throws paper planes at his enemies. The planes are released at set intervals and travel at a set speed despite the character’s relative velocity. If the character increases speed (in this case, exponentially) in the direction of the projectiles, eventually his speed will surpass the speed of the papers he is throwing causing a pileup.

This is a sonic boom. Obviously, the reality of wave propagation is much less discrete than in this example and the sonic boom travels outward in an expanding cone rather than in a single direction. We associate the sonic boom phenomenon with aircraft, but the crack of a bullwhip is perhaps the earliest human-produced example. Also, moving your hand really, really fast might work, too.

Ever assume detonation was just a fancy synonym for explosion? Guess again. Fitting the established theme, detonations are supersonic explosions which produce a shock wave as combustion products (and associated matter) move outward faster than the speed of sound.

On a final, tangential note, a common mistake people make is describing the Big Bang, the inflationary process theorized to have resulted in the creation of our universe, as an explosion. This is an inaccurate description due to the fact that the universe is isotropic at the largest possible scale of observation. Explosions have greater density toward their center and objects further out from the center are necessarily moving faster than objects closer in. While this latter condition happens to describe our own perspective of the cosmos, the explosion model would lead to the unlikely conclusion that we are precisely located at the center of the universe.

Snail
Terrestrial gastropods have evolved a lung as a replacement for ancestral gill structures.

(iii) A compelling saga in macroevolutionary biology is the parallel development observed in the independent transition from water to land by several different clades (plants, arthropods, vertebrates, etc.) over the course of hundreds of millions of years. Varied responses to the challenges of desiccation, gamete dispersal, motility, and gas exchange (among others) were and continue to be primary architects of the biodiversity seen in terrestrial species today.

The human ear is one result of these selective pressures. In particular, the middle ear which contains the three smallest bones in the human body (malleus, incus, stapes) can be understood as a precision instrument designed to transfer information from one material medium to another. In this case, information received through compression waves in the air is amplified and transmitted via the aforementioned tiny bones into the aqueous, sensory environment of the inner ear. This setup was not relevant for our fish ancestors, immersed in liquid and unencumbered by the fact that sound propagates more slowly and less effectively through air than through water.

(iv) Time for an Actually

When I hear the word “tremolo” immediately my mind goes here. In the fuzzy pink photo of Kevin Shields’ Jazzmaster you can just make out a section of tremolo arm visible in the upper left corner. It’s an iconic album cover. MBV’s lush guitar sounds were groundbreaking, but in reality, the whammy bar has nothing to do with tremolo. Tremolo, strictly speaking, involves modifications in volume. Pitch-bending, the relevant technique, is actually, vibrato. Bending guitar strings stretches the strings, shortening their wavelength and increasing the frequency of the sound they produce.

(v) Let’s round things out.

Consider James “Cool Papa” Bell. One of the legendary figures of the American Negro Leagues, Hall of Famer Cool Papa was perhaps the fastest man to ever play the game of baseball. How fast was he? As the story goes, he was so fast, he could turn off the light switch in his room and be in bed under the covers before the room went dark.

From everyone else’s perspective, it appears that lights go out instantly. Light disappears and darkness follows. But what is actually happening when we turn off a light at night? The light cannot just vanish. And the speed of light is not infinite. Each photon emitted just as the light is extinguished is released into the room. If there is no place for the light to escape (such as through windows) then the photons will bounce around the space in constant motion. When individual photons hit a surface (such as a wall) a portion of their electromagnetic energy is converted to kinetic energy absorbed by the wall in the form of heat. This process repeats until the total energy of the light has dissipated.

Lamp
A single photon ricocheting around a dark room.

Let’s visualize this process at the level of a single emitted photon, the last bit of light released before the source lamp turns off completely. The speed of light (c) is approximately 300 million meters per second. Imagine your room is spacious: 10 x 10 m. We will also ignore air, any particles in the air, and objects such as furniture in the room for the sake of simplicity. The longest possible journey for a photon before hitting a wall would be around 14 m (corner to corner). We can split the difference and call the average journey between walls 12 m. Remember, light is fast. How fast? Each second, the photon will bounce off of the walls 25 million times. That is, it would, if it actually took that long for its energy to be exhausted.

On a related note, it is possible to directly measure the speed of light using your microwave oven. The procedure is described in detail here. The basic idea is that (a) wave length and frequency are proportional to one another (b) frequency is a function of time and (c) speed is distance over time.

(vi) This one hits pretty hard.

Illusions

Picture6
The Monty Hall problem. Just think about the probability that you originally picked a goat vs. the car. If you picked a goat (2/3 chance) you want to switch. So…you always switch.

Illusion, Michael. –G.O.B.

(i) Optical illusions are fun. We all have our favorites. There’s one in particular which does not get as much attention as it should. It’s called the McCollough effect and you induce it by alternately staring for five seconds or so at the image below on the left followed by the image below on the right. Repeat this procedure for about a minute or so and then look at the black and white image below the pair.

 

MC1

MC2

 

The fact that the effect can last months following sufficient induction is what makes this one so cool. And a bit scary. Sort of like hiccups that won’t go away. In the back of your mind there is a creeping fear that they may never stop. You might hiccup forty times a minute for several decades or just have the hiccups ruin your life due to an unknown brain stem tumor.

(ii) Infinity is a like a concept, not a number, brah. Yup. ∞ It’s a concept that is notoriously difficult for finite begins such as ourselves to wrap our minds around. To make matters worse (as you are probably aware if you’ve dabbled in the mathematical arts) there are infinities of different size. Now I won’t pretend to have studied or to understand set theory, but it at least makes sense in an abstract way that it would be possible to count forever by whole numbers while also counting forever by half numbers (starting with .5) and there should be more numbers counted in the second case. This next one takes it a step further.

Picture1
Cantor’s proof redrawn.

Mathematician Georg Cantor made it his life’s work to outrage his contemporaries and to blow the minds of the rest of us. Again, I won’t pretend to understand most of it, especially in formal terms, but as for one of his more visual proofs regarding infinity, I think I get it.

The basic idea is that there are an infinite amount of points on both a line of infinite extent and a finite line segment. I suppose the numerical comparison would be something like all of the natural numbers versus the all of the real numbers between 1 and 2. Did I mention that I am not a mathematician?

The proof is pretty genius. Cantor draws a perpendicular line segment down from a point on the original segment which intersects a circle between the segment and the line. What it boils down to is the fact that the angle between the diameter of the circle (parallel to the segment) and the segment drawn from the perimeter through the center of the circle, can become infinitesimally small, but as long as there is a positive value, the segment traveling through the center of the circle to the line will intersect the line at some point. So, they both contain an infinite number of points along their length. QED?

I live on the frozen surface of a fireball. –Julian Casablancas

Or, a wet rock.

The total amount of water on our planet. [https://water.usgs.gov/edu/earthhowmuch.html]
(iii) If there’s one thing that irrationally bothers me, it’s finding out that a certain factoid I’ve been proudly touting is completely false. In fact, one of the two definitions of factoid, an invented fact believed to be true because it appears in print, seems like a strange indictment of everything I am doing here.

I have dreams of writing a book called Actually… which would debunk factoids. Some examples:

“Hey did you know that window glass in old buildings is thicker on the bottom because the glass flows downward very, very slowly.” Actually… it doesn’t.

“January is named for Janus, cuz he looks back to the old year and forward to the new.” Actually… it’s named after Juno. (That source looks dicey. This one might be a double-actually.)

Proxima Centauri is the closest star to us.” Actually… it’s the sun and that’s a trick question.

Bumblebees shouldn’t actually, be able to fly.” Actually…wait, what?

I swear, I’ve heard this last one too many times and the gist of the confusion is applying (tenuous) knowledge of aerodynamics at the scale of humans and small aircraft to the much smaller world of the bumblebee. The implications of orders of magnitude differences in mass and volume on the fluid mechanics involved in terrestrial flight are profound. Particularly salient for flight are the differences in surface area. Let’s do some calculations:

A standard human length of 1.8 m versus maximal bumble bee length of .04 m = 45 times as long.

We can idealize the human and the bee as right cylinders in order to obtain rough estimates of surface area and volume.

Picture1
Human and human-sized right cylinder. Bumblebee-sized human and bumblebee-sized-human-sized right cylinder. NOT to scale.

Human: h = 1.8 m r = .25 m; volume = .35 m³; surface area = 3.22 m²

SA:V = 9.2

This Bumblebee: h = .04 m r = .0056 m; volume = .00000394 m³; surface area = .0016 m²

SA:V = 406.1

On a similar note: ever wonder why insects never get hurt when you throw them to the ground or how squirrels are so successful at avoiding death when falling out of trees? Surface area matters as it produces drag, but mass and the effect of atmospheric pressure on terminal velocity also come into play.

Let’s assume the bee and the human are equally dense, that is, made of basically the same stuff.

Human: Mass = 77 kg; [Density (Mass:Volume) = 220 kg/m³]

Bumblebee: Mass = 220*.00000394 = .00087 kg

The drag coefficient of a standing human shaped object is around 1.0.

Here’s a terminal velocity calculator to play around with. I got a human value of approximately 70 m/s whereas the actual value is closer to 53 m/s. The bee is estimate is around 11 m/s.

To sum up, from the perspective of a bee, air is much more substantial than it is from our own perspective. The experience is much more like navigating what we perceive as a dense fluid, such as water in a pool. The terminal velocity comparisons are made clearer through this analogy when imaging the action of gravity (sinking) on objects of distinct shape and mass when thrown into deep water.

[Below I uploaded a cool (related) article on the various implications of size in biology:]

Schmidt-Nielsen-1975-Journal_of_Experimental_Zoology

(iv) But back to the point. I have been going around telling everyone that the surface of the Earth is smoother than a billiard ball. I heard it somewhere and I loved it. “Guess what guys, the Earth is really, really big.” (How big!?) “It’s so big that you wouldn’t even feel the topography if you had really gigantic hands!”

I believed this hours ago. I wanted to demonstrate that it was true. I got as far as the actual smoothness of a billiard ball before I hit a dead end.

Height of Mount Everest: 8,848 m

Depth of Mariana Trench: 10,994 m

Circumference of the Earth: 40,075,000 m

Smoothness (maximum relief/circumference) = 10,994 / 40,075,000 = 0.000274

Circumference of a billiard ball: .1797 m  (diameter: 0.0572 m * π)

How smooth is a billiard ball?

This is where the trail ran cold. After some further searching I found out that someone had already addressed this. They pointed out clearly and intuitively how dumb the idea of a smoothly polished Earth actually is when you really think about it. Oh well.

(v) This one is called Courage.

 

 

 

Engines

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The main attraction.

Disclaimer: I know nothing about cars.

(i) My son recently became old enough to play with the toy cars I had when I was a kid. Most of them. I’m keeping the Micro Machines on the shelf until we are fully clear of the choking hazard protocol. Aside from the personal nostalgia of rediscovering material traces of my childhood, what struck me is how old some of my model cars are. Yes, I am also sort of old, too, but these have me beat. Seeing dates from the early 1980s and late 1970s embossed on the metal undercarriages surprised me and prompted mental math, leading to the realization that my son handling these battered Hot Wheels and Matchboxes is comparable to me being given toys from roughly the era of the Second World War. Probably made from lead.

Note: I only very recently learned the difference between lead and led. I wasted decades believing they were the same, like read/read.

(ii) My favorite car of the group was the yellow one with the hatchback. The rear compartment could be flipped up, revealing a square, plastic engine which gave slightly and bounced back when pushed. Curious to learn more, I turned the car over.

Matchbox. Peugeot 205 Turbo 16. 1984.

It hadn’t occurred to me as a kid that this toy was modeled on an actual car, or if I had entertained that line of thought, it was ultimately a dead-end given that google and wikipedia weren’t around then. Apparently, this car was a big deal. French. Very popular. Won awards. The version that I had was a suped-up racing edition made for rallying. To my mind, the existence of rally car racing is a separate (somewhat absurd) issue in and of itself. I associate it almost completely with sensationally titled compilation videos of cars swerving off of twisty backroads into screaming crowds of panicked onlookers. My personal experience with rallying is limited to being delayed in Lunahuaná for three hours (while suffering the after-effects of foodborne illness) due to a race scheduled along the only road within the valley.

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Beautiful Lunahuaná viewed through several iterations of photo filtering.

Interestingly enough, the Peugeot 205 T16 is listed as one of the “rallying supercars” unfettered by the sensible restrictions placed on earlier generations of racing vehicles. A series of tragic (fatal) accidents resulted in the restoration of guidelines ensuring that the sport versions would be much closer to the models in general production, ultimately based on the logic that less powerful cars would be easier to control and less likely to be featured in something like People vs Rally Cars | Rally Car Crashes and Saves 2017. (Or, maybe the crashes are expected and the prevalence of “saves” (i.e. narrowly avoiding fatalities) is an acceptable compromise.)

The feature that had drawn my attention as a child, the functional hatchback and its exposed engine, is a key design feature of the vehicle. Mid-engine design places the engine between the front and rear axles allowing for better weight distribution and traction than in cars where the heavy weight of the engine sits at the front. The disadvantage is the fact that the engine is where the back seats should be.

(iii) Engines? I am a not a mechanical engineer, though I have been known to glibly name-check “internal combustion engine” during conversations about the most influential technological advancements in human history, while understanding little about what this technology entails. Are there also external combustion engines? Yup. Steam engines are the most familiar example. The steam, the working fluid, is created by heating water in a mechanism (i.e. a boiler) external to the functional hardware (pistons, turbines, etc.) of the machine where it eventually is used. Internal combustion centralizes this process, as in the familiar case of a conventional automobile engine. Fuel and air mix in the engine (internal) and the combustion process is facilitated by spark ignition. The oxidation of the gasoline produces a hot, pressurized gas that is utilized to work the machine.

Note, though external combustion technology seems a quaint holdover of steampunk lore, this is pretty much how we still generate electricity. Even the most fancy nuclear power plant is essentially a machine that splits atoms in order to boil water.

(iv) Propulsive retro platformer beat: