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The Rising Sea

Writing Mathematics

Mridul Biswas

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Mathematical idea outlives any language

Pythagoras

(c. 570 – c. 495 BC)

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Mathematical idea outlives any language

Pythagoras

(c. 570 – c. 495 BC)

 

 

 

 

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Wanderer above the Sea of Fog

(Caspar David Friedrich)

Intuition and Rigor

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Intuition and Rigor

Wanderer above the Sea of Fog

(Caspar David Friedrich)

Intuition shows the horizon. Rigor gets you there.

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Intuition and Rigor

Wanderer above the Sea of Fog

(Caspar David Friedrich)

Intuition shows the horizon. Rigor gets you there.

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Breaking Down, Building Up

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Breaking Down, Building Up

Start

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Start

Statement

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Start

Statement

Understand defs

And try examples

(by hand)

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Start

Statement

Understand defs

And try examples

(by hand)

Counterexample?

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Start

Statement

Understand defs

And try examples

(by hand)

Counterexample?

False Statement

Yes

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Start

Statement

Understand defs

And try examples

(by hand)

Counterexample?

Mimic example

False Statement

Yes

No

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Start

Statement

Understand defs

And try examples

(by hand)

Counterexample?

Mimic example

False Statement

Proof

Yes

No

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Start

Statement

Understand defs

And try examples

(by hand)

Counterexample?

Mimic example

End

False Statement

Proof

Yes

No

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Mimic example

Start

Statement

Understand defs

And try examples

(by hand)

Counterexample?

End

False Statement

Proof

Yes

No

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Start

Statement

Understand defs

And try examples

(by hand)

Counterexample?

Mimic example

End

False Statement

Proof

Yes

No

The sum of two even numbers is even.

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What Makes a Method Powerful?

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What Makes a Method Powerful?

Exploration

Opens paths to related problems

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What Makes a Method Powerful?

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What Makes a Method Powerful?

Counterexample

Reveals natural counterexamples

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Domain Flexibility

Structural idea, not domain-specific tricks.

What Makes a Method Powerful?

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What Makes a Method Powerful?

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Breaking Down, Building Up

Style: Explore examples, mimic patterns, try to generalize.

EX

CE

IN

FP

DF

EX: Exploration

IN: Intuition

CE: Counterexample

DF: Domain Flexibility

FP: Finishing Proof

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Sandwich Method

Style: Start from both statement and goal, meet in the middle.

EX

CE

IN

FP

DF

EX: Exploration

IN: Intuition

CE: Counterexample

DF: Domain Flexibility

FP: Finishing Proof

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Zoom-Out Method

Style: Step back, see global structure, explore big patterns

EX

CE

IN

FP

DF

EX: Exploration

IN: Intuition

CE: Counterexample

DF: Domain Flexibility

FP: Finishing Proof

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Framework Mimicry

Style: Mimic a known proof for a similar problem

EX: Exploration

IN: Intuition

CE: Counterexample

DF: Domain Flexibility

FP: Finishing Proof

EX

CE

IN

FP

DF

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Blackbox Method

Style: Assume statement, connect to known

EX

CE

IN

FP

DF

EX: Exploration

IN: Intuition

CE: Counterexample

DF: Domain Flexibility

FP: Finishing Proof

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EX

CE

IN

FP

DF

EX

CE

IN

FP

DF

EX: Exploration

IN: Intuition

CE: Counterexample

DF: Domain Flexibility

FP: Finishing Proof

EX

CE

IN

FP

DF

Breaking Down, Building Up

EX

CE

IN

FP

DF

Sandwich Method

EX

CE

IN

FP

DF

Zoom-Out Method

Framework Mimicry

Blackbox Method

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EX: Exploration

IN: Intuition

CE: Counterexample

DF: Domain Flexibility

FP: Finishing Proof

EX

CE

IN

FP

DF

Breaking Down, Building Up

EX

CE

IN

FP

DF

Framework Mimicry

High School Problems

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EX: Exploration

IN: Intuition

CE: Counterexample

DF: Domain Flexibility

FP: Finishing Proof

EX

CE

IN

FP

DF

Breaking Down, Building Up

EX

CE

IN

FP

DF

Framework Mimicry

EX

CE

IN

FP

DF

Sandwich Method

Undergraduate Level Problems

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Crack the Nut, Don’t Become One

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Hammer

Crack the Nut, Don’t Become One

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Hammer

Water

Crack the Nut, Don’t Become One

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Are most square matrix invertible?

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Are most square matrix invertible?

EX

CE

IN

FP

DF

Breaking Down, Building Up

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Are most square matrix invertible?

EX

CE

IN

FP

DF

Breaking Down, Building Up

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Are most square matrices invertible?

EX

CE

IN

FP

DF

Breaking Down, Building Up

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Are most square matrices invertible?

 

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Are most square matrices invertible?

 

 

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Are most square matrices invertible?

 

 

EX

CE

IN

FP

DF

Breaking Down, Building Up

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Are most square matrices invertible?

 

 

EX

CE

IN

FP

DF

Breaking Down, Building Up

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Are most square matrices invertible?

 

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Are most square matrices invertible?

 

 

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Are most square matrices invertible?

 

 

 

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Are most square matrices invertible?

 

 

 

 

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Are most square matrices invertible?

 

 

 

 

EX

CE

IN

FP

DF

Framework Mimicry

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Are most square matrices invertible?

 

EX

CE

IN

FP

DF

Breaking Down, Building Up

EX

CE

IN

FP

DF

Framework Mimicry

 

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Are most square matrices invertible?

 

 

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Are most square matrices invertible?

 

 

 

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Are most square matrices invertible?

 

 

 

 

 

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EX

CE

IN

FP

DF

Zoom-Out Method

Are most square matrices invertible?

 

 

 

 

 

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Are most square matrices invertible?

 

 

 

 

How often does a polynomial vanish?

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Are most square matrices invertible?

How often does a polynomial vanish?

 

 

 

 

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How often does a polynomial vanish?

 

 

 

 

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How often does a polynomial vanish?

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How often does a polynomial vanish?

 

 

 

 

 

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With the rising sea, even distant islands disappear.

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With the rising sea, even distant islands disappear.

Thank You!