The Impact of Computing

1. The Impact of Computing Ganesh Gopalakrishnan School of Computing University of Utah Courtesy to Pat Phillips of Microsoft and Jeanette Wing of CMU/NSF for the slides on Computational Thinking; John Regehr for some of the hardware photographs; etc.

2. Why Compute? • Tool usage is a measure of intelligence and power • Information processing tools have always been widely sought

3. Early Information Processing Tool: An Adder

4. Early Mechanical Computer: Babbage’s Difference Engine (now rebuilt at the London Museum)

5. Nowadays, computers are used everywhere!

6. They will soon replace bar-codes on milk-cans!(RFID tags being experimented by Wal-mart). (Photo courtesy of wikipedia.)

7. With Advances in Electronics have come Much Faster and Capable Computing Devices!

8. Supercomputers have eliminated the need to do experiments by building scale models of airplanes, or mixing (dangerous) chemicals ! • IBM BlueGene • Does 400 Trillion • multiplications per second ! • (Photo courtesy of IBM/LLNL)

9. Virtual Roll-out of Boeing 787 “Dreamliner” Entire Airplane being Designed and Flown inside a Computer (Simulation Program). The first plane to fly is the real one (not a mockup model). (Photo courtesy of Boeing.)

10. Supercomputers can now safely simulate explosions ! This simulation employed 600 processors for approximately 1 week in a  sophisticated parallel application to simulate all of the fluid  dynamics, thermodynamics, chemical reactions and structural mechanics of this system from fundamental laws of physics. [Steve Parker, CSAFE, U of U]

11. The Entertainment Art Engineering (EAE) Program at the U of U – a Machinima Movie

12. And yet… We need to apply Computational Thinking! We do not acquire technical skills simply from the use of technology any more than engineering skills evolve from using automobiles or aeronautical engineering skills from flying. Robert Tinker, Alvaro Galvis, and Andrew Zucker The Concord Consortium

13. What is Computational Thinking? Asking: What is the power and limit of human and computer intelligence? Asking: How difficult is the problem? Asking: How can it be solved? Asking: How can technology be applied to the problem? Asking: What computational strategies might be employed?

14. CT is about developing an appreciation of large numbers • Compute installation • consumes 3 MW of power • Can provide for 20,000 • average homes • Equal to 100,000 brains • thinking hard!

15. What it’s not… It’s not just more technical details for using software It’s not thinking like a computer It’s not programming (necessarily) It doesn’t always require a computer It’s not yet one more thing to add to your curriculum

16. How is it different from other learning strategies? Not just procedural Not just constructionist Not just integrated

17. Why is it important? It moves students beyond technology literacy It creates problem solvers instead of software technicians It emphasizes creating knowledge rather than using information It presents endless possibilities for creatively solving problems It enhances the problem-solving techniques we already teach It allows us to see that computing (like any other paradigm) is a double-edged sword, and we need to work hard to get the good elevated and the bad demoted

18. CT enables asking questions about ALL computers: 0 0 1 1 2 2 3 3 3 01 01 01 01 1 1 1 01 01 1 1 0 0 101 101 101 The solution for this Post Puzzle is 3, 2, 0, 3, 1 i.e. Reads 1 01 01 1 01 Reads the SAME ! One can mathematically prove that NO computer can solve ALL “Post Puzzles.” One Post Puzzle is …

19. And yet… 0 1 2 3 01 1 00 1000 0 0 101 001 The shortest solution for this Post Puzzle has 206 steps! One cannot predict how long the solution sequence is…

20. Application of the Impossibility Result: Given a Grammar for parsing, it is impossible to tell, using a computer, whether the grammar can be used to parse things in TWO incompatible ways (similar to the following) : Given 2 * 3 + 4 = 10 we should consider it to be saying (2 * 3) + 5 = 10 and NOT 2 * (3 + 4) = 10

21. Everything is going “Computational” Computers are like telescopes and microscopes for learning in EVERY branch of science and many branches of mathematics! Computational • Physics • Biology • Chemistry • Mathematics • Computer Science • Law • Economics • Aeronautics • Education

22. For instance… Even many mathematical proofs cannot be written out or checked (in our lifetimes) without the use of computers Famous Computer-Finished Proofs • The Four Color Theorem • The Kepler Conjecture

23. And yet… We depend on computers for controlling and predicting virtually every aspect of our lives… • Hospitals no longer can manually check which patients are admitted and what their symptoms are. They have to rely on the data the computers have • We no longer have the ability to forecast weather, process bankrolls, or hey, even watch television, without some computer playing a major role • Billions more of applications (the sales of small computers approaches the 10 Billion mark each year)

24. And yet… They can cause an immense digital divide • The older population of the nation • inability to use the web • yet all the information is there • sometimes one has to see certain patterns and type into a web browser • The illiterate population

25. And creep into the least suspected places.. Use of Linux in the real world • Desktops and laptops for sure • But these too: • Toyota Prius • Sony Bravia TV • Various Linksys routers • Doorlocks in the School of Computing • What if there was one common bug in these versions of Linux? one common attack?

26. Who is responsible for bugs? How can we prevent bugs? “Execution Checking” “Model Checking” • Employ mathematically based debugging methods, such as “model checking” • debug Scientific Computing codes using • debug thread software such as Linux using • empirically shown to have very few “bug escapes,” assuming that the modeling was right, and the verification tools themselves worked correctly (and the human, using the tool, did not misinterpret its results… etc..)

27. And yet… They can have a significant carbon foot-print • The first Petascale computer will consume 20 MW of electrical power • Equivalent to the electrical energy use of 200,000 average homes • If the software we use on these machines is buggy and wastes one month of simulation time… ?

28. And yet… This is also one of the best hopes for world-wide unity, awareness, education… • The Web • Skype • Email • $100 laptop for poor nations • …

29. And yet… One needs a balanced view of the world • The world does not owe us anything – it was here before us! [ Mark Twain ] • We owe a lot to the world • The carbon footprint can wreak havoc by 2050 if kept unmitigated • Leaving the world better than we found

30. And yet… All technologies are double-edged Learn to have the good ascending and the bad descending in impact

31. Conclusions • Be capable of understanding what computers are • where they are being employed • where they are creeping into our lives • how indispensable they have become • how to keep using them to our advantage • to use them to understand how we think • use them to understand who we are • beware of the digital divide they cause when used poorly • the carbon footprint they leave when used wastefully • the toxic waste they cause when not recycled • WITH ALL THIS, be part of the exciting world of computing, whatever your field of study be !!

32. All this fun and Fantastic Employment Potentials!!

33. So how do you get involved with the U ? http://www.cs.utah.edu

34. Extra slides

35. Another Example (of CT): Exponentials • 4 – size of a typical family • 40 – family reunion • 400 – runs in a high-scoring cricket match • 4000 – cost of a good desktop machine • 40000 – cost of a good high-end car • 400000 – one-sixth of Utah’s population • 4000000000 – 3/4th of the world population -- > number of seconds a human lives Developing an appreciation for the “Exponential”

36. Exponentials • 4 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 0000000000 number of atoms on earth • Using logarithmic amount of ink, we can talk about huge numbers! • Using N amount of ink, one can talk about 2^N Developing an appreciation for the “Exponential”

37. Exponential algorithms, Polynomial algorithms, Unknown complexity algorithms • Poly: Sorting the employee records of N employees • Exp: The number of arrangements of N employees in a single-file procession • Unknown: Given N employees, are there K who form a clique? • Unknown, possibly harder: Given N employees, is it that NO K employees form a clique?