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Einstein Said… How big is a trillion?

“…imagination is more important than How long would it take me to snap my knowledge. For knowledge is limited to all fingers a million times, at a rate of one we now know and understand, while snap per second? imagination embraces the entire world, and A million seconds is about 11.6 days. all there ever will be to know and A billion seconds is about 32 years! understand.” A trillion seconds is about 31,709 years!!

Scott, Michael (2011-05-24). The Warlock (The Secrets of the Immortal Nicholas Flamel) (p. 320). Random House, Inc.. Kindle Edition. *Discussion primarily drawn from The Week.

Course Description Highlights MATH/IDST 120 What is the Golden and how do artists and scientists use it? … Is our social order , Shape and Space influenced by or spatial “Mathematics is a study of awareness? …The course format emphasizes patterns and relationships; a guided exploration and critical thinking; students science and a way of thinking; an are required to demonstrate an understanding art , characterized by order and of the material through journal writing, internal consistency; a language , presentations and a library research paper. using carefully defined terms and symbols; and a tool .“

North Central Regional Educational Laboratory http://www.ncrel.org/sdrs/areas/issues/content/cntareas/math/ma3ques1.htm

Texts Satisfies

Symmetry, Shape, and Space , Kinsey and 100-level mathematics course Moore, New York: Wiley Publishing, 2002 100-level humanities course with the related software, Geometer’s Writing intensive course Sketch Pad. Required in Arts Concentration Flatland - A Romance in Many Required in Composites Technology Dimensions , Abbott, Edwin A. New Jersey: Princeton University Press, 1991 (or any other un-annotated copy).

1 Required Tools Topics Covered

A reliable compass, protractor, scissors, a Euclidian straight-edge, and #2 pencils including Mathematics and Social Satire ( Flatland ) colored ones are required. Other useful Ruler-and-compass Constructions things: rubber eraser, graph paper, The measuring tape, tracing paper, cellophane () tape, and various other types of fasteners, And one other topic, time permitting, that are optional. varies from semester to semester.

Big Ideas Becoming…

Critical Thinking Late in the 90’s the Southern Maine Writing Intensive Technical College began offering a Liberal Studies degrees. Hands-on Activities 2003 - Change of mission and name - Southern Maine Community College The call went out for more LS courses. In the meantime….

Flatland, Edwin Abbott Critical Thinking

Characters are plane figures Critical Thinking (reasoning) is a mental Carefully crafted process of analyzing and evaluating Satire information in order to improve thinking (reading, writing, listening.) Women’s plight Caste systems “Irregulars” 4th physical dimension Before Einstein Progressions

2 Activities

Let’s spend the rest of our time doing some of the activities.

The Paul/Elder Model www.criticalthinking.org

Memorize or Understand? Experiment

A Demonstration Have a sheet of paper and something to Students want to memorize a process for write with (no writing yet though!) doing mathematical things. I’m going to display a series of letters for 15 I think this is a mistake. seconds. Try to memorize as many of them in order as you can. With real understanding comes ease. I will then give you a chance to write down what you remember. Ready?

Memorize! Write!

Write down what you remember. Would it help to UNDERSTAND the pattern? ZOT TFF SSE NTE TTF FSS What if I told you the first three letters represented the words zero, one and two?

3 Understand!

Perimeter Area ZOT TFF SSE NTE TTF FSS Volume

Composite Figures C= 2π r How much space?

Find the perimeter of the figure below. How much of the space within the is taken up by the shaded region?

r=2.5 cm

h = 4cm

l = 10 cm Ans: 33.7 cm Problem devised by Paul Lockhart in A ’s Lament .

A Challenge Area - Rectangle (opposite sides have equal length)

This figure has 4 rows of 7 area units. How What if the shaded region was obtuse? many area units are there overall? REMEMBER! The answer to area problems will always be in terms of units squared . Can we devise a formula? 7 units

4 units

Good journal fodder!

4 Area - Parallelogram (opposite sides parallel) Formula – Trapezoid (two opp sides parallel)

If we “chop off” the height →→→ one trapezoid on the left… …and add it to the right… two trapezoids, one …what do we get? rotated Ans: rectangle! So… As long as we know When we join the two height, we can find the figures, what do we get? area as before.

Area = (# of base units)(# of height units)

Devising a Formula A Challenge

Bases are labeled. Each trapezoid is ½ of Could this work? the parallelogram.

Base = b 1 + b 2 Height = h

Area = h(b 1 + b 2)

Area trap = ½ ◦h(b 1 + b 2) You tell me! ☺ (Good fodder for journaling if you want a challenge)

Area of Any Polygon Do you have your scissors?

Can you see how Let’s see if we can the triangle can prove to ourselves help us with any that the is ? correct. Find the area of one of the Handout! and multiply by the number of sides! Is this starting to look circular?

5 Simplify Volume 1  (a+ b )2 = 4  ab  + c 2 2 

Playing w/Rice Composite Solids – 5 pt bonus

1. How do the flat images An ice cream cone is 10 centimeters deep and relate to each other has a diameter of 4 centimeters. A scoop of ice (describe in terms of cream with a diameter of 4 centimeters rests on geometry)? the top of the cone. 2. Cut out and assemble If all the ice cream melts into the cone, the two solids. will the cone overflow? 3. What is the relationship between the volume of If the cone does not overflow, what the pointed solid and the of the cone will be filled? regular one? (Hint: use rice!) Don’t forget to show your work! 4. What are your shapes called?

Flatland Unit Dimensional Analysis

Reading the novel raises questions The diameter of the sun is 870,000 miles. Social order The sun card to complete our planet Treatment of “irregulars” and women model sets would be approximately how A fourth physical dimension big? State your answer in terms of feet. Understanding Scale – a necessary 4.9 feet prerequisite 870000mi 6 in 1 ft × × = 4.9 ft 1 88734mi 12 in

6 Explorations of Scale My Answers Coming!

1. What is the scale of the planet cards? 6 in=== 88 , 734 miles (Jupiter)

2. Why is there no sun card? Because it would be too big!

The diameter of the sun is 870,000 miles. Our model Jupiter is 6 inches in diameter.

Largest in the World 1 inch = 14,789 miles

There is a 40-mile model along Route 1 1. What would be the distance between Neptune and between UMPI and Houlton. the sun using the scale of these planet models? State your answer in terms of miles. Finished 2003 2. The diameter of the sun is 870,000 miles. The sun Scale 1 mile = 93 million miles card to complete our planet model sets would be Jupiter approximately how big? Photo by M York 3. If the earth was the size of a pepper corn (0.08 inches),

• How large would Jupiter be?

• What would be the distance between the Sun and Neptune? http://www.umpi.maine.edu/info/nmms/solar/index.htm

My Answers R & C Constructions

1. What would be the distance between Neptune and the sun using the scale of these planet models? State your answer in terms of miles. 2.98 miles

2. The diameter of the sun is 870,000 miles. The sun card to complete our planet model sets would be approximately how big? State your answer in terms of feet. 4.9 feet

3. If the earth was the size of a pepper corn (0.08 inches), (1) how large would Jupiter be? 0.896 inch (2) What would be the distance between the Sun and Neptune? 2,350 feet

7 R & C Constructions Interesting Pattern!

Do we have time to look at GSP files? What do we learn? Logical thinking? Working without measurements? Find patterns?

Building “Brick Walls” Building “Brick Walls”

Take a couple of boxes of tiles; work Use dominoes to build walls that are two pairs. Take notes! bricks tall. When it is oriented horizontally, one With one domino you can build a wall two domino is one “brick” high and two bricks bricks tall like this: long. Here is a “brick wall” that is two bricks tall using one Here is a brick “brick”.

Building “Brick Walls” Building “Brick Walls”

How many ways can you build a wall two How many ways can you build a wall two bricks high if you have two bricks? bricks high if you have three bricks? My answer coming… …four bricks?…five and six bricks? Work this out using the chart in your handout. Two ways!

8 A certain man put a pair of rabbits in a place surrounded on all sides by a wall. How many pairs of rabbits can be produced from that pair in a year if it is supposed that every month each pair begets a new pair which from the second Building “Brick Walls” month on becomes productive?

# of Tiles Configurations # of Ways

1 January How many pairs will there be in June? 2 February Eight!

March 3 How many pairs will there be by December? 4 April One hundred 5 and forty-four! May 6

The Series in an Octave 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 14 4, 233...

Find the of successive pairs of numbers, putting the larger numbers in the numerator. 1 1 5 Here are the first few = 1 = 1.66 values. 1 3 •13 notes in the chromatic scale 2 8 Calculate about 6 = 2 = 1.6 •8 natural notes more and tell me what 1 5 •5 sharp/flat notes you think about the 3 = 13 •3 black-note group results. 1.5 = 1.625 2 8 •2 black-note group •1 octave

1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 14 4, 233... 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 14 4, 233...

After the first few iterations, the ratio 21 89 =1.615 = 1.618 begins to approximate (pronounced 13 55 “fee”) and hovers there indefinitely. 34 144 =1.619 = 1.618 Golden Ratio (Φ) ≈ 1.61803399 21 89 55= 233 = 1 + 5 1.618 1.618 φφφ = 34 144 2

Before we’re through we will prove that the exact value of Phi is this radical expression.

9 AC= AB “Phee, Phi, Pho, Phum™”* The Divine Proportion AB BC

Both are correct. This straight line is divided in proportions equal to Phi as in “pie” is preferred, apparently. the golden ratio.

A B C

m AC = 5.03 cm m AB = 3.11 cm m AB = 3.11 cm m BC = 1.92 cm

m AC m AB = 1.61803 = 1.61803 m AB m BC http://goldennumber.net/pronounce.htm

Explorations The

These are two pictures of the same cone. The ratio of the height of the man to the distance from the floor to his navel is 1.618… The measure of his shoulder to his finger tip then his elbow to his finger tip... Phi. Do you conform to the ideal Pine cone pictures taken from: http://www.mcs.surrey.ac.uk/Personal/R.Knott/Fi presented here? bonacci/fibnat.html

Let’s look at Ex 10, 11, & 13. The Constructions Ex 10 Which one? (I’m not telling!) Can you make a prediction about what will happen when you ask 20 people the same question? Prediction = hypothesis Ex 13 What would be your hypothesis for Ex13? In a very real sense, these Unit 4 activities are “original research”.

10 Bisect a base to find?... Bisect a base angle to find?...

A Handout! ADC and FDC are similar! Bisect angle ADC… A A

Construct a circle with center 36 °°° at D. 36 °°° Bisect the distance between

the intersections at i 1 and i 2. i1 …and then… 108 °°° F 72 °°°

i D 2 C 36 °°°

° 72 °° 72 °°° 36 °°° 72 °°° D C D C

Bisect a base angle to find?... Bisect a base angle to find?... A tells us that in When DC = 1, AD = Φ and A A similar triangles since DC = DF = AF, corresponding sides are proportional. And we have said that in the similar Φ AD DC AD DC = triangles we found that = DC CF DC CF but there's one more ratio we need... F F AD DC AF ? Φ F = = = = 1 DC CF CF 1 1 All of which leads us to... D C Bisecting one of the equal in the Golden Triangle D C D C yields a segment, in this case AC, that is divided by in the Extreme and Mean Ratio!!!

Erase Erase Exact Value of Phi

We've discovered that... A We derive a different way to label sides and 1 then... AD=φ , AF = 1 andFC = φ Can we also agree?... 1 AD= AF + FC If we substitute the derived φφφ F values in this expression we 1

get... φφφ 1 φ = 1 + φ D 1 C

11 111 φ = 1 + “Plug and chug”! An Exact Value φφφ

−b + b2 − 4 ac : φ = If someone asked you for the exact value of 2a Phi, this is what you would give them. a = 1 b = − 1 1 + 5 φφφ = c = − 1 2 b2 −4 ac = 5

Is there something missing in our formula?

+5 Points!!! +5 Points!!!

A board is 60 inches long. Cutting the board into the Golden Ratio may be accomplished using the 60 === x proportion below to find the length of each segment. x60 −−− x What are the lengths of the two pieces? (Round your answer to 2 places.) x2 +60 x − 3600 = 0 60 === x x60 −−− x x ≈≈≈ 37.08 60−x ≈−≈≈ 22.92

http://opinionator.blogs.nytimes.com/2012/09/24/proportion-control/?emc=eta1 http://opinionator.blogs.nytimes.com/2012/09/24/proportion-control/?emc=eta1

111 111 φ = 1 + φ = 1 + What is the value? φφφ What is the value? φφφ 1 1+ 1+ 1 + 1 + 1... + 1 1+ 1 1+ Φ=1 + 1 + 1 + 1...? + 1+ ...

1 + 5 1 + 5 φφφ = φφφ = 2 2

12 The Mean Calculator Trick

These are just two examples of the constant Enter the number 1.6180339887 mean, one of a plethora of interesting this number. properties of the extreme and mean ratio. Notice anything interesting? Result: 2.6180339887 Enter the number 1.6180339887 again… Raise it to the power of -1 (or hit the 1/x key) Result: 0.6180339887

Exercise 3 - Answers Exercise 4 - Answers

Tessellations Tessellations

A is a tiling made of repeating shapes This tiling is periodic… with no gaps or overlapping sections spread …a fixed pattern that across a plane. is repeated over and over again in a predictable way and where tiles are not rotated.

http://www.scienceu.com/geometry/articles/tiling/definitions.html

13 Tessellations Tessellation

This tiling is This is a regular aperiodic. tessellation.

This is not.

http://www.mathpuzzle.com/chaotile.html

Rule #1 Regular Tessellations

Every regular and semi-regular tiling must We know that can have the angles of the polygons meeting at tessellate the plane. What a vertex with a sum of angle measures of other individual polygons exactly 360°. can tile the plane in this Regular – one polygon way? (That is vertex to Semi-regular – two or more polygons vertex, edge to edge using only one shape .)

Let’s play!

Regular Tessellations Regular Tessellations

Ans: equilateral triangles Ans: regular hexagons

14 Naming Scheme Name 3 Regular Tessellations

Because it takes 4 squares meeting at a vertex to complete a tessellation with this shape, geometers give the configuration the name …. 4.4.4.4

close up of the intersection...

This tile This tile 4.4.4.4 3.3.3.3.3.3 6.6.6 has 4 has 4 sides. sides. This tile This tile has 4 has 4 sides. sides.

Naming – Semi-regulars These 18 all fit once.

# of Polygons Name Does it tessellate? This semi-regular tiling of octagons So our chart 6 3.3.3.3.3.3 Yes and a square is named 4.8.8 for the should look like 5 3.3.3.3.6 same reason. 5 3.3.3.4.4 this now. 5 3.3.4.3.4 4 4.4.4.4 Yes 4 3.4.4.6 4.8.8 4 3.3.6.6 4 3.3.4.12 This This What about the angles? Equal to 3 6.6.6 Yes 360 °°° without gaps or overlaps? figure figure 3 4.8.8 Yes has 8 has 8 3 3.7.42 sides. sides. 3 5.5.10 This 3 3.12.12 figure 3 4.6.12 has 4 3 4.5.20 sides. 3 3.9.18 3 3.8.24 3 3.10.15

3.7.42 – Does it work? The Rules

Rule 1: Every regular and semi-regular tiling must What is the measure of have the angles of the polygons meeting at a vertex the interior angles of a with a sum of angle measures of exactly 360°. regular 42-agon? Rule 2: Every regular and semi-regular tiling must Ans: 171.43° have at least 3 polygons and no more than six Can a 3.7.42 meet at one meeting at each vertex. vertex with 360°? Rule 3: No semi-regular tiling can have four Does it work for two? different types of polygons meeting at a vertex. Do we really want to Rule 4: No semi-regular tiling can have vertex construct 42-agons? configuration k.n.m where k is odd and n≠m. Let’s understand Rules Rule 5: No semi-regular tiling can have vertex #4 and #5. configuration 3.k.n.m unless k = m.

15 Tessellations - Summary Yes! They tessellate!

Here is the # of Polygons Name Does it tessellate? 6 3.3.3.3.3.3 Yes completed chart. 5 3.3.3.3.6 Yes You should now 5 3.3.3.4.4 Yes 5 3.3.4.3.4 Yes have found three 4 4.4.4.4 Yes regular 4 3.4.4.6 No, but 3.4.6.4 does 4 3.3.6.6 No, but 3.6.3.6 does tessellations and 8 4 3.3.4.12 No semi-regular ones. 3 6.6.6 Yes 3 4.8.8 Yes PHEW!!! 3 3.7.42 No 3 5.5.10 No 3 3.12.12 Yes 3 4.6.12 Yes 3 4.5.20 No 4.8.8 3 3.9.18 No 3 3.8.24 No 3 3.10.15 No

Yes! They tessellate! Yes! They tessellate!

3.4.6.4 3.12.12 4.6.12

Yes! They tessellate! Yes! They tessellate!

3.6.3.6 3.3.3.3.6 3.3.4.3.4 3.3.3.4.4

16 Parallel Translation

We’re going to make a template that we can use to trace a tiling Irregular Tilings grid. Grab several blanks. Cut a random piece out of one side (don’t cut away the vertices!) How did Escher do it? Tape this cutaway to the parallel side opposite the cut. Use this as a template to trace around to make a grid of your irregular shape. Do it carefully and this could be part of your homework!

Glide Reflection Midpoint Rotation

Find the midpoint on one side of Cut a random piece out of your shape. (Here I’ve rotated all one side (don’t cut away the 4 sides.) vertices!) Cut a random shape out of that Reflect this piece (turn it side that begins at a vertex and over!) ends at the midpoint. Tape the resulting cutaway to the parallel side. Rotate this piece 180°. Tape the resulting cutaway to the Again, use this as a template. other half of that same side. Again, use this as a template.

http://euler.slu.edu/escher/in dex.php/File:Smaller-and- Side Rotation How did he do it? smaller.jpg

Cut a shape out of one or more sides. Rotate these pieces 90° around one of the vertices and tape it to the new side. Smaller Again, use this as a template. and Smaller

By the way, all of these techniques work best on “regular figures” grids like squares, triangles and hexagons.

17 Quilter’s Square

Non-Periodic

Roger Penrose - 1974

Roger Penrose in Playing with the foyer of the Boats Mitchell Institute for Fundamental Diamonds Physics and Stars Astronomy, Texas A&M University, standing on a floor with a .

http://en.wikipedia.org/wiki/Penrose_tiling

Leading Eventually to 6… And Finally to two…

Most Penrose tilings you find will be made up of these two figures.

18 THANK YOU!!!!

Questions? Want my slides? Send me an email. [email protected]

http://www.sciencenews.org/pages/sn_arch/10_12_96/nonpd.htm

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