Professor Michael SternbergHead of Bioinformatics

Imperial College London

• Bring a working scientist into a schoolBring a working scientist into a school

• A Royal Society Partnership Award to A Royal Society Partnership Award to Mathilda Marks-Kennedy SchoolMathilda Marks-Kennedy School

• The Royal Society was set up in 1660 The Royal Society was set up in 1660 to help science and has been very to help science and has been very important ever since. important ever since.

Science Museum

Many scientistswork in laboratories

My team just use computersto crack the code of biology

• TodayToday– Writing in codeWriting in code– How people at Bletchley Park broke the How people at Bletchley Park broke the

German codes during World War IIGerman codes during World War II– How computers were invented to help crack How computers were invented to help crack

codescodes

• Next weekNext week– Bletchley Park VisitBletchley Park Visit

• Two weeks timeTwo weeks time– How Biology uses codesHow Biology uses codes

• Here is a way to send a secret messageHere is a way to send a secret message

• Write with a special pen on paperWrite with a special pen on paper

• Give your message to your friendGive your message to your friend

• Your friend has a special torch and can Your friend has a special torch and can read the message.read the message.

• If someone else gets the paper, they If someone else gets the paper, they could also a the special torch and could also a the special torch and read your message!!!read your message!!!

• Not the best idea!!!Not the best idea!!!

1) First two people meet and agree on the code

2) - The first person can then write the message in code and send it to the second person

3) The second person gets the message and then changes the code back to the message. Changing the code back is called ‘deciphering’.

• Message Alphabet: Message Alphabet: abcdefgh…xyzabcdefgh…xyz

• Code Alphabet: Code Alphabet: AABCDEFGH…XYZBCDEFGH…XYZ

• Message Alphabet: Message Alphabet: abcdefgh…xyzabcdefgh…xyz

• Code Alphabet: Code Alphabet: ZZAABCDEFGH…XYBCDEFGH…XY

• Message Alphabet: Message Alphabet: abcdefgh…xyzabcdefgh…xyz

• Code Alphabet: Code Alphabet: YZYZAABCDEFGH…XBCDEFGH…X

Letter in message

Letter in code

First two people meet and agree on the code

Let’s use the shift codeand when the real letteris ‘a’ the code will be ‘Y’

2) - The first person can then write the message in code and send it to the second person

Message : helloCode: : FCJJM

3) The second person gets the message and then changes the code back to the message. Changing the code back is called ‘deciphering’.

Code: :FCJJM Message : hello

Code: L ORYH LFH FUHDPMessage:

Code: L ORYH LFH FUHDPMessage: a

Code: L ORYH LFH FUHDPMessage: a dgns auw ujwse

Code: L ORYH LFH FUHDPMessage:

Code: L ORYH LFH FUHDPMessage: i

Code: L ORYH LFH FUHDPMessage: i love ice cream

Code: LORYHLFHFUHDPin the code there are 3H, 2F, 2L most common letters in ENGLISH is Eoften used are: A, H, I, N,O,R,T

Code: LORYHLFHFUHDPMessage: i?o?ei?e?rea?

Code: LORYHLFHFUHDPMessage: iloveicecream

Message Alphabet: abcdefghijklmnopqrstuvwxyzCode Alphabet: ZEGNALFDROHTUCBPJIMKSQWVYXEGNALFDROHTUCBPJIMKSQWVYX

Scramble up alphabet

But still can be cracked by guessing that code letters that are used often are for letters like E in English

• In World War II, the Germans used a In World War II, the Germans used a machine called the Enigma Machine machine called the Enigma Machine to make very clever codesto make very clever codes

• The Enigma Machine used several The Enigma Machine used several wheels to scramble up the messagewheels to scramble up the message

Type in message

Coded letters light up

Wheels

These codes were cracked here in World War II

First they built a machine with wheels and lights called a ‘Bombe’.

Later they built the very first computer which was called ‘Colossus’.

• We have learnt:We have learnt:

– shifting or scrambling the alphabet shifting or scrambling the alphabet makes codesmakes codes

– codes can be cracked by hard workcodes can be cracked by hard work– the first computer was built by the the first computer was built by the

British to crack the Enigma code in British to crack the Enigma code in World War II.World War II.

• Mrs Ben Ze’ev for suggesting this partnershipMrs Ben Ze’ev for suggesting this partnership

• The Royal Society for providing fundsThe Royal Society for providing funds

• Dr Suhail Islam (Imperial College London ) for Dr Suhail Islam (Imperial College London ) for the wheels and the moviethe wheels and the movie

• My daughter for advice on what I should say My daughter for advice on what I should say and how I should make the slides.and how I should make the slides.