Skip to main content

The Beauty of Dandelin Spheres


I've been fortunate enough to run into this seemingly tame video about ellipses by 3Blue1Brown, and I think I've found a nice anchor to base my love for math on. Though I read about it in textbooks and was content enough to feel I understood it, I never stopped to ponder why an angled section of a cone would give an ellipse. And I mean going down into the depths of it to really find a mathematically sound way I could represent it.

I think this provides a good insight into how our imaginative minds work too. I often find myself feeling convinced of something when I successfully understand the bare basics of it. Maybe this has something to do with the Dunning Kruger effect? Perhaps so. Maybe our minds are still primitive in this sense. Even a plastic shovel can do the job of lifting off the topsoil and so can an excavator. But to dig deep into the earth, a shovel breaks immediately. And so do weak superficial proofs which provide immediate satisfaction. 

I couldn't have been bothered to delve deeper into how that actually worked than be convinced seeing a cone being sliced in my head. It's funny how almost all banes of our mental reward system come from the fact that our brains are still hardwired to caveman parameters! Procrastination, Gluttony, and the arch enemy of curiosity. Never mind, all this for another day maybe.

Seeing how Dandelin 🠉 proves this using clever geometry has put a broad smile on my face. This is probably one of my favourite mathematical proofs, not because of its potential to be expressed visually alone, but also because of how simple and fundamental the pre requisites to understanding it are. I highly recommend watching the video yourself.


Comments

Post a Comment

Popular Posts

An Ode to Rain

  An Ode to Rain “So what’s your favourite time of the year?” she asked, swinging a crossed foot lazily in the air, as she swirled a stirrer in a tiny cup of hot chocolate. Perhaps the time when I used to lick melted drops of vanilla from the back of my hand? blind to the fact that I was painting a modern art piece on the pavement with ice cream. What a charming memory.  Summer, I should say.  What about the little shivers my feet do, tucked away in the layers of heavy blankets, while my nose and ears complain of the biting cold to my toes.   Hot soups, lazy mornings, clouds from the mouth when I speak and hoodies with cosy pockets to slide my hands into.  Winter beats summer, surely.  To be fair, I was born in spring, the perfect gradient from the cold seasons to hot summers. Just the right temperature, reasonably humid with a drizzle of rain here and there. It had never been dramatic enough to create a lasting memory of itself though. Glancing out the caf...

My Notes-app Up For Auction

It’s a late night with Alex Turner on full blast in my ears, never on the speakers though.  To make others around feel the full weight of unsolicited emotion of music, feels wrong. Who am I kidding, perhaps they don’t feel a thing. How rude. The flair of words seems to have abandoned me today so it’ll be bare bones. I find myself constantly backspacing the words I type with a vigour. A quickly written sentence followed by a slight pause full of fear, before my finger reaches out to the delete button on the far right. Desperately trying to put the tarp back on naked emotions uncovered bare. No more backspacing though. I’ve even gotten rid of the Grammarly extension. It shows me how a sentence rephrased, sounds more assertive but I digress. Enough fine tuning. Times like these I wish I had a typewriter. Imagine a canvas pedestal with hands, pointing to the parts where the acrylic paints fail to smudge. No one would ever pick up a paintbrush. Okay, enough rambling. This would have bee...

To Sculpt a Poem

Sometimes, I wish I was Michelangelo.  I wish I could see the angel, Before I set her free from the stone,  My mind. But alas, I am no sculptor nor painter. Us writers, we are magicians, mages and warlocks. Conjuring words from thin air, Stringing them together as we go. Sometimes,  I wish I could peek at her tender hands through the uncut rock. So I may chip away stone day and night to carve them to perfection. But, I possess no hammer, chisel nor rake. Sounds trapped in letters. Letters stitched to form words. Words which I must now weave, Into a warm winter blanket that shall not exist in the real world. The real world.. where it's cold. Ah yes. Words. They are the only tools I wield. How do I ever see my creation like Michelangelo saw his angels, When I am being asked to embrace her, Before I pour life to her very inception? - P.S