Meet John (pictured) - master carpenter, master craftsman, and part-time mathematician. John is my neighbor, and for the last few weeks he has been constructing this "structure" in his front yard.
I know that many of you are stressed-out over the SATs, ACTs, SAT IIs and EIEIO (a test only given by Professor O. McDonald), but you deserve a break today. Listen closely: drop the practice test book and back away slowly from the college applications and I promise you that no one will be harmed! Take a moment to examine John's front-yard project. Drop me a line if you think you know what he's building.
- Hint # 1: Put on your math-based thinking cap.
- Hint # 2: Since I have not seen any wildebeasts, sloths or rhinos walking 2x2 in the neighborhood, I can speak with some certainty that he is not Noah and said construction in not an ark.
Good Luck!
P.S. A prize will go to the first person to unwrap this mystery.




Comments (Closed after 30 days to reduce spam)
Posted by: neha on November 27, 2007
Posted by: Star on November 27, 2007
Posted by: Claire on November 27, 2007
Posted by: 0 on November 27, 2007
Not mathematical enough I suppose .. it also reminds me of the description of Malcom's chaos models in Jurassic park..
oh, but I've been looking at it as though it was one piece rather than two. Möbious strip seems more on the right track .. but I'd imagine something orientable..I'll have to think about it
~Donald
Posted by: donaldGuy on November 27, 2007
Posted by: 0 on November 27, 2007
Posted by: Kim on November 27, 2007
Posted by: 0 on November 27, 2007
Posted by: Ana L on November 27, 2007
Posted by: Ana L on November 27, 2007
could it be a large pi symbol? or maybe an excessivly large dog house.
actually i think it might be a blow up or something small... a cell perhaps
Posted by: marcus on November 27, 2007
Posted by: Chelsea on November 27, 2007
Posted by: vika on November 27, 2007
Posted by: nick on November 27, 2007
It definitely looks like a hyperbolic parabaloid! It might just be a coincidence that it is MIT in both cases, but you may find this article interesting. Cheers!
http://www.nytimes.com/2005/02/15/science/15origami.html
Posted by: Jai on November 27, 2007
Posted by: Stephen L on November 27, 2007
Posted by: Louis on November 27, 2007
Posted by: 0 on November 27, 2007
Posted by: Stephen L. on November 27, 2007
I win; we can all go home now.
p.s. I love Mr. Neha.
Posted by: Jess on November 27, 2007
Or perhaps a model of a piece of hyperbolic space.
The opposite diagonal bars on the opposite sides interest me... it seems like if each side was identified with its opposite then it would be a projective plane embedded in hyperbolic space?
Posted by: Berkeley on November 27, 2007
Posted by: Louis on November 27, 2007
It wouldn't happen to be automatic acceptance, would it?!!
=]
Posted by: Javi on November 27, 2007
Posted by: Kim on November 27, 2007
A hyperbolic paraboloid (saying that just makes you sound smart no matter what).
Posted by: Kevin X on November 27, 2007
Posted by: Chris on November 27, 2007
Posted by: E Rosser on November 27, 2007
If he is planning to leave the construction in his yard, then he might also use it to hang/support plants in a garden.
Thanks for the riddle!
Posted by: … on November 27, 2007
Posted by: Merritt B on November 27, 2007
Posted by: Merritt B on November 27, 2007
would you happen to be the same Merritt B that went to the VA Governors School at CNU this past summer?
if so... hi! (this is, obviously, Donald)
I still don't know.. I agree that it looks like some form of hyperboloid .. but obviously thats too simple.. plus I'd actually have to agree with paraboloid over hyperboloid .. because two of the traces are parabola .. and the third is .. a rectangle? (which is obviously not a conic)
hmm .. this is a challenge ...
~Donald
Posted by: donaldGuy on November 27, 2007
Posted by: Lauren S. on November 27, 2007
Posted by: donaldGuy on November 27, 2007
either we already have the answer (unlikely) .. or we need to think more outside the box (or calculus book .. as the case may be)
Posted by: donaldGuy on November 27, 2007
Posted by: izzy on November 27, 2007
Posted by: SKishore on November 27, 2007
Posted by: Travis on November 27, 2007
Posted by: Edgar on November 27, 2007
Posted by: YHuang on November 27, 2007
Hi, yes, same me (and I have not stopped believing, for what it's worth).
@Edgar
Perhaps it's some form of a Lorentz Attractor, although pic #3 shows both 'wingtips' pointing down, unlike the rendering done by my Mac's Grapher, which is the only place I've seen one. It seems to be divided in the middle (pic #4), perhaps this is a clue - maybe it'll be flipped?
Posted by: Merritt B on November 27, 2007
Posted by: 0 on November 27, 2007
Then I thought that he might be building the top to a gazebo. That would be a little bit more practical than hyperbolic geometry in his front yard. And it would make a rather nice gazebo for in the summer, maybe with some ivy hanging off of the side...
Posted by: Karen on November 27, 2007
I think he is building a bus stop roof. If you notice, the two (parabolicky curvy sides) things do not appear connected, which can be seen in pictures 1, 3, & 4. I believe they are to be made as some kind of roof because the lips curve downwards in the center, but bank upwards to the sides.
(so if they do this then depending on how he puts it up it could increase the amount of shade available to those underneath, I think)
If they are meant to be parts of a roof, then they could be attached together at the top by poles where a bench could be placed underneath for people to sit under. To me, if it was built up like that it would look like those bus stops you see with roofs on them to keep the elements off you while you wait for the bus!
Or it is indeed, a giant pringle.
This is fun.
Posted by: Collin on November 27, 2007
Posted by: A. Noni Mus on November 27, 2007
Posted by: Zaira on November 27, 2007
Posted by: Keshav P on November 27, 2007
Posted by: Javi on November 27, 2007
Posted by: Calvin on November 27, 2007
I wish it was a butterfly though...
Posted by: butterfly girl on November 27, 2007
Posted by: anonymous on November 27, 2007
Regardless, the use of the word "ark" is a good clue. The embedding in hyperbolic space sounds even better, simply since it's not constructed "in an ark"--i.e., it's not taken from the "arc of a circle/sphere/whatev," and so it can't be easily described using the Euclidean metric, or at all.
The other good clue, even if it's a bit of a stretch, is the fact that no animals walk "2x2." 2x2 could be the dimension of the matrix that would define the linear transformation on the plane to arrive at a projection of that shape in R^2--so, maaaybe it's derived from something more complex--perhaps not from any kind of linear transformation?
And, as a total guess, the edges kind of remind me of what happens when you invert the complex plane via a Mobius transformation. (If that's the case, what luck! ALL we will have to do is find the Riemann sphere somewhere hidden in the picture and we will have solved this veritably challenging mathematickal puzzle!)
Anyway, I'll continue to think it's use is a hammock. I need sleep.
Posted by: Will on November 27, 2007
Posted by: Brant on November 27, 2007
Posted by: intleyes on November 27, 2007
I also thought some sort of transform might be involved ... but unfortunately I have no experience with them .. the first one that came to mind was some sort of Fourier transfer... which also works with the butterfly concept... but that would also violate the [2x2] theory ... I think (I'm basing this off the slightest knowledge drawn from wikipedia in the last ten minutes)
Posted by: donaldGuy on November 27, 2007
Posted by: Marissa on November 27, 2007
Posted by: Collin on November 27, 2007
Either way, it looks really cool.
Posted by: Shamarah on November 27, 2007
A complete 3D structure from the side view, would look like a double cone, but of course it's hyperbolic. My best guess is an hourglass shape; when stood up in its rectangle frame the structure would be a giant hourglass.
Posted by: Anonymous on November 27, 2007
Posted by: Paul on November 27, 2007
Posted by: Travis on November 27, 2007
Posted by: V on November 27, 2007
Posted by: Paul on November 27, 2007
Posted by: Paul on November 27, 2007
Probably it will go over his driveway, which appears to be behind and not in front of the house, so I don't think any silly zoning codes would make it illegal.
Posted by: Collin on November 27, 2007
Posted by: L on November 27, 2007
Posted by: 0 on November 27, 2007
Posted by: 0 on November 28, 2007
Posted by: ag on November 28, 2007
Posted by: MX on November 28, 2007
Posted by: HK on November 28, 2007
You made my day!
Posted by: Edgar on November 28, 2007
Posted by: Utkarsh Sharma on November 28, 2007
Posted by: 0 on November 28, 2007
Posted by: 0 on November 28, 2007
Posted by: Amour on November 28, 2007
Posted by: Keshav P on November 28, 2007
Posted by: Zev Chonoles on November 28, 2007
Posted by: EV on November 28, 2007
Posted by: Keshav P on November 28, 2007
It looks like an airfoil?
And... wow, all that math is pretty impressive... and utterly incomprehensible
Posted by: Hyun Jin on November 28, 2007
Posted by: milena '11 on November 28, 2007
Posted by: Janice on November 28, 2007
Posted by: Leko on November 28, 2007
Posted by: mtd on November 28, 2007
Posted by: Manders '13 on November 28, 2007
Posted by: Keshav P on November 28, 2007
Posted by: Name Spelled Backwards on November 28, 2007
Posted by: 0 on November 28, 2007
Posted by: tom on November 28, 2007
I'm stuck in 1.00. I know that I shouldn't be on here, but I couldn't resist. it looks flammable. LOL.
I'm stuck in 1.00. I know that I shouldn't be on here, but I couldn't resist. <3
do you guys need cookies anytime soon? I'm contemplating a giant cookie bake for the holiday season.
Posted by: Justine on November 28, 2007
SER I HAV NO IDEAS.
Posted by: Kamur INDIA on November 28, 2007
Posted by: Rena on November 28, 2007
How about a wooden Xmas bow for the holidays?
Posted by: Polarisking on November 28, 2007
Posted by: Louis on November 28, 2007
Posted by: Lydia on November 28, 2007
Posted by: Nick on November 28, 2007
(So in a way a hyperbola without the top)
Posted by: Thomas Fronk on November 28, 2007
Yes, I'm dull and simple.
Posted by: Nick on November 28, 2007
And Paul: Does one really need a reason to be building a hyperbolic paraboloid? Hm?
Posted by: harrison on November 28, 2007
Posted by: Craig on November 28, 2007
Posted by: Craig on November 28, 2007
Posted by: Craig on November 28, 2007
He is going to cover the frame with wood, and then drill holes into the cover. He will put bird seed or yummy vegetable plants under it, and then sit back to watch a living example of the Pidgeon Hole Principle, as more birds flock to the feast than he has drilled holes!
Posted by: Erika on November 28, 2007
Posted by: Erika on November 28, 2007
Posted by: Paul on November 28, 2007
Posted by: MarcoMV on November 28, 2007
I don't know .. it could be relevant
http://en.wikipedia.org/wiki/Instantaneous_phase
Posted by: donaldGuy on November 28, 2007
Posted by: MarcoMV on November 28, 2007
as for the purpose...I was thinking of some kind of reflector, but only because we've been doing optics in physics lately. That doesn't really work for me though, as I can't think of why the heck he would want a hyperboloid or paraboloid reflector...
Or it could be some type of sundial. The curvature might have something to do with the varying angle of the sun between summer and winter. Seems simple enough...
Or, I believe this was said before, he could be building a roof for something. Perhaps for a shed, garage, or doghouse...I don't know. But a hyperboloid would quite effectively eliminate the need for any gutters.
Posted by: Johonaton on November 28, 2007
Posted by: Johonaton on November 28, 2007
Posted by: Krishna on November 28, 2007
Posted by: Leko on November 28, 2007
Posted by: Travis on November 28, 2007
are you the Leko from TX HAS this summer?
Posted by: Collin on November 28, 2007
Posted by: ronaldolycra on November 28, 2007
Posted by: Craig on November 28, 2007
Posted by: Will on November 29, 2007
Posted by: Will on November 29, 2007
Posted by: 0 on November 29, 2007
hold ur breath..........
it's actually a christmas present for PAUL from EDLA!!. Edla's dad is bryan's neighbour and edla asked him to make a special version of the calabi yau manifold for paul, so that sweet paul could spend his vacations counting the dimensions and thinking about edla!!
There u go!;-)
Posted by: rafael on November 29, 2007
Posted by: rafael on November 29, 2007
Posted by: Vihang on November 29, 2007
Sorry for the triple post!
Posted by: Rafael on November 29, 2007
Posted by: Doubltap on November 29, 2007
or
skateboard ramp for his grandkids.
(Moms can have fun too!)
Posted by: just a mom on November 29, 2007
Posted by: Shantini on November 29, 2007
something that contains many parabolic curvatures?
I know it sounds strange
but if it is not an ark , this is the first thing that comes to my mind
Posted by: Ying Wei on November 29, 2007
...I just really wanted the (2^7)th post. :D
Posted by: Matt, PSU '11 on November 29, 2007
Also, I'm inclined to agree with Paul that it might be important to figure out the reason behind building the structure. Solar panels seem plausible from the pictures, but considering we're going into mid-winter in Massachusetts when the days are getting shorter, that hypothesis appears suspect. Nonetheless, I think that's a good approach to try to solve this problem. Form follows function. =)
Posted by: Arkajit on November 29, 2007
Posted by: cc on November 29, 2007
Posted by: Leko on November 29, 2007
Posted by: Travis on November 29, 2007
Posted by: Trenten'16 on November 29, 2007
Posted by: James on November 29, 2007
Posted by: Ross on November 29, 2007
Posted by: onome on November 29, 2007
Posted by: Louis on November 29, 2007
Posted by: Travis on November 29, 2007
Posted by: Chi Feng on November 29, 2007
Posted by: onome on November 29, 2007
It could be a herbolic parabloid shaped hill that a reindeer family could be mounted upon, and he would cover the "surface" with green lights to make it look like grass!
He's a holiday genious.
Posted by: Collin on November 29, 2007
Posted by: Chi F. on November 29, 2007
Posted by: 0 on November 29, 2007
Posted by: Carolina on November 29, 2007
Or a helicopter propeller.
Or a hyperbola.
Or a hammock.
Or a fence.
Or a hat.
Or the beginnings not of a Trojan horse for Caltech...but of a Trojan BEAVER for Caltech!!!
DUN DUN DUN!!!
Posted by: taran on November 29, 2007
how close is he to finishing this structure?
Posted by: 0 on November 30, 2007
(Couldn't resist.)
Posted by: Paul on November 30, 2007
Posted by: MarcoMV on November 30, 2007
Posted by: Jane on November 30, 2007
It looks as if it is a lateral section of a hyperboloid rotated horizontally!
The hyperboloid in question may be described by
x^2/a^2 + y^2/b^2 - z^2/c^2 = 1
I wonder if it has any asymptotes.
I wish they taught this in Grade 12. Life would be so much fun!!!!
Posted by: Leo V on November 30, 2007
Parabolas are the better curves to build because there's no wasted wood. If you look at the wood grain direction and notice a glue joint down the middle of each board of wood parallel to the grain, maybe you can see why. Leo V, in the finished structure the asymptote lines are made explicit. Bryan, I hope you'll post a link to the answer soon!
Posted by: Jane on November 30, 2007
Posted by: Leko on November 30, 2007
Posted by: sunless in seattle on November 30, 2007
WOW! Never challenge the individual or collective math knowledge of the MIT blogging community. THe contest is over. In fact by post 3 the contest was over. To be gracious, the first 20 to correctly ID the structure will receive a prize. If you are
Find below a message from my neighbors Jane and John Kostick.
------------------------------------------------------
Hi, this is Jane writing, and that's my husband John whose creation you're discussing. I can't even begin to tell all of you how much fun we've been having reading all of these comments. The first prize should go to Ana L, who was the first to identify the shape correctly as a hyperbolic paraboloid. A prize should also go to, at the very least, Kim, Vika, Jai, Berkeley, Louis (for using the word "quadric"!) and probably some others but there are getting to be too many to keep track of. For figuring out what its use will be, a prize should also go to Merritt B for writing "a fiendishly complicated trellis" and Lauren S for suggesting it will "at least focus sunlight onto his rather sad garden...." That really made us laugh! Also, Karen for suggesting a gazebo and ivy and intleyes for seeing that it's a walkway cover. Also, Zev Chonoles for a good idea and Harrison for a great question/comment. Did I miss anyone? Let me know. First prize is a six-axis bronze star. The 19 runners up get a tetraxis. Bryan will contact the winners by email.
Now go to www.quadricdesigns.com to see a slideshow with more up-to-date pictures and find out what a tetraxis is!
-Jane and John Kostick
Posted by: The Nance Effect on November 30, 2007
Posted by: Travis on November 30, 2007
Posted by: Ana L on November 30, 2007
Posted by: Lauren S on November 30, 2007
Posted by: Carolina on November 30, 2007
Posted by: Karen on November 30, 2007
If this is the case, the design is very novel and spectacular but rather inefficient because only a very small part of the supporting pipe/rail would be in focus from a very small area of the reflecting surface - the rest is idle. One could do far better with a simple E-W parabolic cylinder adjusted seasonally in small moves.
Posted by: Frank Michael on December 1, 2007
Posted by: Jai on December 1, 2007
Posted by: Yangyang Guo on December 1, 2007
I was the 7th person on this blog to say "hyperbolic paraboloid" in my entry. Though I thought it was a Pi symbol.
If I am considered a winner, please give my prize to Melis. She truly is an inspiration.
Posted by: Chris on December 1, 2007
Posted by: Stephy on December 2, 2007
Posted by: anonymous on December 2, 2007
Posted by: Travis on December 2, 2007
BTW..I DID use the word quadric!!!! Really!!!!!
Look at my answer!!! Maybe I deserve a reward???
Anywhich ways....this was the the most fun filled "geometric mystery" ever!
Please do post pics of the completed structure!
I'm a grade 12 student from Dubai. After answering your question, I had a long conversation with my math teacher about quadrics and learnt a whole lot about them.
Cheers
Leo V
Posted by: Leo V on December 4, 2007
To see the tetraxis prize, go to www.youtube.com/jjkostick
Posted by: Jane on December 4, 2007
no brownie pts, for finding a spelling mistake?? ("wildebeest"),and it could have been a 'calabi-yau' manifold,cudn't it?
oh..i feel pathetic..but anything for a recognition frm MIT..however distant!!
Posted by: raphael on December 4, 2007
This is way too cool!!!
Leo is just a screen name. I've always liked the name Leo. I am Lionel Vaz. This prize means a lot to me. It's more than just a prize!!!!!
I'm excited for two reasons.
Firstly, I'm am applying to MIT for fall 2008. As an interntional student, the competition for admission is fierce. But I have a strong belief in my will to succeed. This is prize just serves to re-affirm my belief. It's a milestone for me!
Secondly, math is my first love. What can be better than being rewarded for doing something you love the most????
A big THANKYOU to all you people.
Thankyou Bryan for posting this. I can't explain how much this means to me.
Its amazing...something as simple as a wooden structure has set of this "tsunami" of happiness within me. WOWWWWWW!!!!!!!!!!!!!!!
Cheers
Lionel.
Posted by: Leo V on December 4, 2007
Posted by: Jay (Hopeful MIT Fall 2008 parent) on December 4, 2007
Posted by: Jay (again) on December 4, 2007
Hmmm... He has no official porch, and it's hard to tell from the pictures exactly which shape it belongs to.
My best guess is a sun-roof seeing how the four poles are so uniformly distributed around the frame
Posted by: Johnson C on December 4, 2007
Posted by: angi on December 4, 2007
Thanks again for this intriguing contest!
Posted by: Zev Chonoles on December 6, 2007
Posted by: Jane on December 6, 2007
Posted by: 0 on December 10, 2007
Posted by: Merritt B on December 13, 2007
You can always hope that he put it in your tube!
Posted by: Karen on December 13, 2007
Posted by: Lauren S. on December 13, 2007
..Arigatou Gozaimasu (Thank you very Much =D)
Posted by: KUI on December 14, 2007
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