Traffic Lights & the Intersection

The number 5 may not seem very interesting at first or even arbitary as a Mathematician might exclaim after perusing the haphazard juxtaposition of the immaculate sharp corners of the top over the squiggly bottom half. This is the 5th issue after all and the number of words in the very helpful mnemonic I learnt back in primary school “ROY Got Buckled In Verelem” for the colors Red, Orange, Yellow, Green, Blue, Indigo & Violet also happens to be 5. Perhaps this is more than enough a reason for me to write this piece. 


In Astronomy & Physics however we do not restrict ourselves to the colors that are visible to the naked eye. We extend the notion of color to include things such as gamma rays, X-rays (for when I visit my dentist) and stretch things out all the way back to Radio Waves, which I shall use when I send this letter to the editors. In fact in here I will draw my inspiration from physics to attempt to offer a possible way of approaching a particular problem which has arisen in the wake of a collective attempt to address oppressive institutions that are based on skin color, gender, sexual orientation and class amongst other things. This has been coined the Intersection or Intersectionality by Crenshaw et. al [1]. The main argument here is that the prejudices which follow from such classifications are generally interlinked, sometimes reinforcing each other and therefore cannot be discussed separately if much progress is to be made.


It turns out what my science teacher left out along with the mnemonic was that there were only 3 colors to begin with, just Red, Yellow & Blue and that this was all one needed in order to make the other 4 (Green, Orange, Violet & Indigo). At the intersection of Red and Yellow one arrives at the color Orange, that of Blue and Red gives you Indigo. Therefore if one wishes to discuss the colors that are visible to the naked eye when the Rainbow shines bright behind Table Mountain, one need only be concerned with just 3 colors. This might be helpful for instance if we were say planning to hike up the mountain in order to paint our own rainbow, we would only need to pack 3 colors along with the brushes. The quality found in this line of thinking and reasoning is the general mode of attack in the physical sciences if one wishes to study and make sense out of anything.


This is no reductionism to point at which one is left nothing [2], it is the elucidation of certain unique qualities or characteristics of a problem that further allow one to discuss it’s connected aspects if one wishes to go there. A single molecule of H2O is dry for instance and knows nothing (or does it?) about the liquid form of a collection of such molecules we usually describe as being wet. This is the realisation that certain behaviours and properties that one observes in a physical system only appear when the system is large enough. In the case of water, at the molecular level you do not observe flow, wetness etc. you only get these at the collective level. We generally refer to this as Complexity [3]. 


We do not despair however, we go on to say that given the complex nature of a collection of water molecules (I mean they’re wet and hard to hold onto), what are some of the things we might begin talk about to describe what we now see? In the case of water these turn out to be the Volume (how much there is), the Pressure (how tightly squeezed is it) & the Temperature (how hot is it). In my glass of water all the individual molecules share these properties in common, the power of this line of thinking is that I do not have to have to keep checking what each and every single molecule is doing all the time, although I can tell what each is undergoing at any given moment given just a thermometer, a pressure gauge and a ruler, all very useful things to have at hand. This approach is extremely useful given the mind numbing nature of the world of the very small, Quantum physics. Perhaps this is the scandal in modern physics, that the collective nature of things is much easier to discuss than their individual aspects. In going very large and zooming out of a problem we find that we can go very small once again (up to a certain point) which then allows us to talk about the individual aspects, this branch is called Statistical physics. 


Speaking of large things, a puzzle once occurred in the cosmos. Some old white males with draping grey beards and spectacles (as one is usually made to believe) saw these very bright stars through the eyes of their telescopes, much brighter than what stars at such distances were supposed to be, and concluded that these must have been a new type of star. They were named Quasars short for Quasi Stellar Radio Sources. Radio sources because they were first discovered using Radio telescopes, Radio here does not refer to my stereo which is generally tuned to F.M.R [4] but the type of wave that both my stereo and cellphone uses to receive and send signals. What this means is that if your stereo could tune in at those frequencies, you would be able to eavesdrop on what those stars were emitting. They were termed Quasi-Stellar because initially it wasn’t clear if these would also be visible using “naked eye” (optical) telescopes. They were “heard” before they were seen so to speak. Later on it was possible to confirm that these “stars” were indeed also visible to optical telescopes. So bright, so “loud” yet so far! This was troubling. 


We now know that Quasars are in fact galaxies and not stars! We had to wait until bigger and powerful telescopes were built for this. These galaxies are thought to possess Black Holes in their cores (black holes are collapsed stars which do not emit any light 5 but have a very strong gravitational pull) which sucks stuff in, causing things to heat up and flare and therefore appear bright at such large distances.

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3C175 is not only a quasar, it is a galaxy-fueled particle cannon. Visible as the central dot is quasar 3C175, the active center of a galaxy so distant that the light we see from it was emitted when the Earth was just forming. The above image was recorded in radio waves by an array of house-sized telescopes called the Very Large Array (VLA). Shooting out from 3C175 is a thinjet of protons and electrons traveling near the speed of light that is over one million light-years long. The jet acts like a particle cannon and bores through gas cloud in its path. How this jetforms and why it is so narrow remain topics of current research.  Image and explanation from APOD 05/09/01. 


The story with Quasars is worth mentioning because here once again you have things which are visible when the object is viewed from a certain perspective and not from others. Quasars were first thought to be just radio sources (using radio telescopes) and were later confirmed to be also visible light sources with the advent of more powerful optical telescopes. As mentioned, we now know that they are not only visible in both frames, but are in fact galaxies which means they are much larger than the people who first saw them initially thought. Quasars now fall broadly in a class of what is referred to as Active galaxies, the thing that is either active or not is the black hole at the core. This acts as the engine which drives the brightness. Fortunately the black hole at the center of our galaxy is thought to be inactive, else the brightness emanating from the core would be such that we would not be here discussing traffic lights and intersections. Again a picture depicting a Quasar taken using a visible light telescope is just plain boring, all you see is a very bright point source. If however you take a picture of the same object using a radio telescope you begin to see gigantic jets (much larger than the parent galaxy) shooting out from the core of the galaxy. What’s even more impressive and illuminating is a composite picture of the two, where both radio and visible pictures have been combined to form a single image. This I believe is at the heart of Intersectionality.


It does not mean however that we cannot discuss what we see in the visible, radio, X-ray etc. in turn and keep building things up in this way and then put it all together once again to see what we can get out. Discussing things at once can be very confusing in physics since the size and scale of things can vary broadly depending on what you wish to talk about. In the humanities it also confusing because it allows people to jump between topics (without any warning) in the name of a theory which does not actually advocate for such. Returning back to my glass of water it could be that I’m just getting ready with my ruler to try and measure the Volume when I hear a fellow activist shout from behind the fridge “what about the pressure?” At this point the one who’s been hiding behind the stove calls out “Temperature!”. It is true that all three are related and are needed to quantitatively account for the glass of water in my hand. How we measure them need not be, a ruler seems much easier to obtain than a thermometer.


Race, gender, sexual orientation amongst other categories and the prejudices which follow characterise the pain that different people groups experience in varying degrees. As a black male residing in white Cape Town, on a daily basis I am made fully aware of which end of the scale I happen to fall in. It is helpful therefore to place these categories alongside each other in order to begin to fathom the plight of the individual who happens to reside at their intersection. In doing so we may need to formulate a paradigm or a language for discussing these things, perhaps by drawing analogies from the physical sciences which may very well serve as the traffic light at the intersection. 


[1]Kimberle Crenshaw, 1989

[2]It would defeat the purpose to not pack any paint at all

[3]see the article “More is different” by Philip Anderson

[4]Fine Music Radio

[5]see Hawking’s Radiation


Article by Sukuma Sukummah

For Sukuma’s work in astronomy visit / in vinyl selections visit @sukummah (instagram) / for work on Jazz Reviews visit / (Lake Magazine)


Left-hand side image by Usisipho GogelaScruffy Sinusoidal (9 May 2016):

“This makes me think of a few things. Firstly, Plato’s Theory of Forms, where a form is an idea or conception of perfection. Secondly, mathematics, arguably humanity’s greatest achievement in terms of abstraction, formalisation and order. And then putting these two ideas together: transforming a completely mental, abstract, “perfect” idea into something tangible, messy and imperfect. The abstract idea in this case was a sine wave (with modulating amplitude and frequency). The method of transforming the form into physical was a long exposure light painting. I will leave the exact technique/situation as an open mystery.” 


Check out Usisipho’s website here




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