⬣ ABOUT ⬣ First broadcast in 1982, Countdown is iconic British TV. Its numbers game is the perfect balance of challenge and simplicity. In this video, I analyse the hidden mathematics of the game: What are the hardest targets, best numbers to draw, and optimal tactics?
⬣ TIMESTAMPS ⬣ 00:00 - Introduction 04:46 - How Many Possible Games? 10:00 - Reachable Numbers from a Given Game Set 14:00 - Results and Tactics: Small Numbers 24:00 - Results and Tactics: Large Numbers 31:00 - Scary Numbers 40:05 - Outro
⬣ CHALLENGE ⬣ So to clarify, I want to see a list of the percentage of solvable games for ALL options of large numbers. Like I did for the 15 options of the form {n, n+25, n+50, n+75}, but for all of them. The options for large numbers should be four distinct numbers in the range from 11 to 100. As I said there are 2,555,190 such options so this will require a clever bit of code, but I think it’s possible! Email me via my website if you think you have it!
⬣ INVESTIGATORS ⬣ I’ve never seen that colour on my screen before. I’m hoping you excel yourself and slug out the solution. Now is the perfect time to join the investigation.
⬣ ABOUT ⬣ First broadcast in 1982, Countdown is iconic British TV. Its numbers game is the perfect balance of challenge and simplicity. In this video, I analyse the hidden mathematics of the game: What are the hardest targets, best numbers to draw, and optimal tactics?
⬣ TIMESTAMPS ⬣ 00:00 - Introduction 04:46 - How Many Possible Games? 10:00 - Reachable Numbers from a Given Game Set 14:00 - Results and Tactics: Small Numbers 24:00 - Results and Tactics: Large Numbers 31:00 - Scary Numbers 40:05 - Outro
⬣ CHALLENGE ⬣ So to clarify, I want to see a list of the percentage of solvable games for ALL options of large numbers. Like I did for the 15 options of the form {n, n+25, n+50, n+75}, but for all of them. The options for large numbers should be four distinct numbers in the range from 11 to 100. As I said there are 2,555,190 such options so this will require a clever bit of code, but I think it’s possible! Email me via my website if you think you have it!
⬣ INVESTIGATORS ⬣ I’ve never seen that colour on my screen before. I’m hoping you excel yourself and slug out the solution. Now is the perfect time to join the investigation.
⬣ ABOUT ⬣ I had no idea that the systems surrounding the Navy Enigma machine were completely different to that of the Army, making the code much tougher to crack. In this video, James teaches me these differences and discusses what Alan Turing managed to achieve in breaking this code.
⬣ TIMESTAMPS ⬣
⬣ INVESTIGATORS ⬣ Nothing for you here. Sorry!
⬣ CREDITS ⬣ Music by Danijel Zambo, Tobias Voigt, and Apex Music.
⬣ ABOUT ⬣ Alan Turing: WW2 hero, father of computing, and played by Benedict Cumberbatch in 2014 biopic "The Imitation Game". James Grime joins me to analyse this film and how some of its historical inaccuracies were a disservice to Turing's character.
⬣ TIMESTAMPS ⬣ 00:00 - Intro 01:30 - The Imitation Game -- Accuracy 11:10 - A Disservice to Turing 16:37 - Turing, Computers, and AI 24:52 - Verdict
⬣ INVESTIGATORS ⬣ Nothing for you here. Sorry!
⬣ CREDITS ⬣ Music by Danijel Zambo, Tobias Voigt, and Apex Music.
The Imitation Game footage (C) The Weinstein Company
⬣ ABOUT ⬣ There’s much to admire about the Golden Ratio, but its significance is largely overblown. In this video, we separate some of the facts from the fiction, while analysing Darren Aronofsky’s “Pi”.
⬣ TIMESTAMPS ⬣ 00:00 - Intro 02:57 - What is the Golden Ratio? 04:53 - The Fibonacci Sequence and the Golden Ratio 10:54 - Nature and Diophantine Approximation 15:14 - Hurwitz’s Inequality 21:20 - Numerology and Gematria 26:09 - Is Pi Good? 29:02 - Verdict
⬣ ABOUT ⬣ Only certain regular polygons are constructible with compass and straightedge. Why? And why did the first person to prove it after 2000 years get no recognition? In this introduction to Field Theory, we’ll find out, and along the way we’ll also prove other impossibilities like why cube doubling and angle trisection are impossible. Happy Birthday Pierre Wantzel!
⬣ TIMESTAMPS ⬣ 00:00 - Intro 02:13 - Why ONLY the four operations and Square Roots 04:14 - Field Extensions 14:37 - Minimal Polynomials 25:54 - Cube Doubling is Impossible 31:50 - Angle Trisection is Impossible 36:35 - Constructible Polygons: The Gauss-Wantzel Theorem 50:12 - Why Pierre Wanzel got No Recognition
⬣ INVESTIGATORS ⬣ Nothing for you here. Sorry!
⬣ REFERENCES ⬣ Biographical details on Wantzel to be found in: Jean-Claude Saint-Venant (1848). “Biographie: Wantzel”. Nouvelles Annales de Mathématiques Série 1, 7: 321-331. Found, with English translation by Lauren Murphy, here: divisbyzero.com/wp-content/uploads/2018/02/saint-venant.pdf
Amazing treatise on possible reasons why Wantzel was never credited: Jesper Lützen, “Why was Wantzel Overlooked for a Century? The Changing Importance of an Impossibility Result” Historia Mathematica, Vol 36 (4) 374-394, 2009. Found here: sciencedirect.com/science/article/pii/S031508600900010X
Pierre Wantzel’s original paper, with proofs adapted in the video: Wantzel, L. (1837), "Recherches sur les moyens de reconnaître si un Problème de Géométrie peut se résoudre avec la règle et le compas", Journal de Mathématiques Pures et Appliquées, 2: 366–372. Found here: http://visualiseur.bnf.fr/ConsulterElementNum?O=NUMM-16381&Deb=374&Fin=380&E=PDF
⬣ CREDITS ⬣ Music by Danijel Zambo, Tobias Voigt, and Apex Music.
⬣ ABOUT ⬣ Despite being easy to state, the problem of constructing regular polygons confounded the Ancient Greeks. It took over 2000 years to make progress, and in this video we’ll trace a path through history to learn what innovations allowed more polygons to be constructed.
⬣ TIMESTAMPS ⬣ 00:00 - Introduction 01:47 - Ancient Constructions 08:14 - What the Ancient Greeks Lacked 11:20 - From Geometry to Numbers 16:28 - From Numbers to Equations 21:58 - From Equations to the Complex Plane 31:48 - Gaussian Periods 36:10 - Final Construction
The Thirteen Books of Euclid’s Elements. T. L. Heath (1908)
J. Derbyshire: "Unknown Quantity: A Real and Imaginary History of Algebra" Joseph Henry Press (2006)
Al-Kamil treats irrational quantities as numbers in their own right H. Selin, U. D'Ambrosio: "Mathematics Across Cultures: The History of Non-Western Mathematics" Springer (2000)
Al-Mahani’s definition of rational and irrational M. Galina: "The theory of quadratic irrationals in medieval Oriental mathematics" Annals of the New York Academy of Sciences 500 (1987) 253-277.
Al-Khwaizmi quadratic equations Al-Jabr - Al Khwarizmi
Sridhara’s method D. E. Smith: “History of Mathematics” Vol 2 Dover (1925)
Tombstone story C. W. Dunnington: "Carl Friedrich Gauss: Titan of Science" Hafner Publishing (1955)
⬣ CREDITS ⬣ Intro music by Tobias Voigt. Other music by Danijel Zambo and Apex Music.
⬣ ABOUT ⬣ AlphaGeometry is a new AI system developed by DeepMind that can solve Olympiad-level geometry problems. This has been hailed as a leap forward in AI reasoning, but is it? In this video, break down how AlphaGeometry works and give my general thoughts on the use of AI in mathematics.
⬣ TIMESTAMPS ⬣ 00:00 - Introduction 01:04 - How Does AlphaGeometry Work? 02:27 - Triangle Facts 03:55 - IMO 2008: Problem 1 (Setup) 06:50 - IMO 2008: Problem 1 (AlphaGeometry’s Solution) 13:11 - IMO 2008: Problem 1 (Discussion) 18:22 - Is AlphaGeometry Good at Mathematics? 22:21 - The Use of AI in Mathematics: Good or Bad?
⬣ INVESTIGATORS ⬣ Nothing for you here. Sorry!
⬣ REFERENCES ⬣ Trinh, T.H., Wu, Y., Le, Q.V. *et al. “*Solving olympiad geometry without human demonstrations.” *Nature* **625**, 476–482 (2024). doi.org/10.1038/s41586-023-06747-5
K. Appel and W. Haken “The Existence of Unavoidable Sets of Geographically Good Configurations” Illinois J. Math. 20 (1976), 218-297
⬣ CREDITS ⬣ Music Intro music by Tobias Voigt. Other music by Danjel Zambo and Apex Music.
⬣ ABOUT ⬣ We've all seen the beloved DVD Screensaver and been excited to see it hit the corner. But is this guaranteed to happen? If it happens once, will it happen again? And long will you have to wait between corner hits? All these questions answered and more via the ancient number theory of Euclid and Diophantine.
This video was sponsored by Brilliant.The Film with the Most MathsAnother Roof2023-12-28 | To try everything Brilliant has to offer—free—for a full 30 days, visit brilliant.org/AnotherRoof The first 200 of you will get 20% off Brilliant’s annual premium subscription.
⬣ ABOUT ⬣ X+Y (known in the US as "A Brilliant Young Mind") follows Nathan, an autistic teen who pursues his dream of competing in the International Mathematical Olympiad. This film has a surprising number of fully-stated problems that I break down in this video.
⬣ TIMESTAMPS ⬣ 00:00 - Intro 02:54 - Problem 1 09:15 - Problem 2 13:54 - Problem 3 15:02 - Problem 4 19:16 - Autism in X+Y 22:30 - Discussion of the Film 28:36 - Verdict
⬣ CREDITS ⬣ Music by Danjel Zambo and Tobias Voigt. "Leaving" by Cory Alstad.
This video is sponsored by Brilliant.How Hard is an Oxford Maths Interview? Feat. Tom Rocks MathsAnother Roof2023-11-26 | To try everything Brilliant has to offer—free—for a full 30 days, visit brilliant.org/AnotherRoof The first 200 of you will get 20% off Brilliant’s annual premium subscription.
⬣ ABOUT ⬣ After failing to score an interview with the University of Oxford back in the day, I've always wondered what the process is like. Luckily for me, Dr Tom Crawford is a fellow maths YouTuber who was all too happy to ask me some interview questions!
⬣ ABOUT ⬣ Cube is a 1997 horror film in which a group of strangers wake up in a 3D maze filled with traps. Escape relies on their ability to crack the mathematical puzzle of the cube's construction. But does the mathematics in the film stand up to scrutiny?
⬣ TIMESTAMPS ⬣ 00:00 - Intro 00:53 - Mathematics of the Rooms 09:51 - Mathematics of the Traps 11:59 - Quality 16:05 - Verdict
⬣ CREDITS ⬣ Music by Danjel Zambo and Tobias Voigt.
⬣ REFERENCES ⬣ [1] - Treffert DA. The savant syndrome: an extraordinary condition. A synopsis: past, present, future. Philos Trans R Soc Lond B Biol Sci. 2009 May 27;364(1522):1351-7. doi: 10.1098/rstb.2008.0326. PMID: 19528017; PMCID: PMC2677584.How π Emerges From a Forgotten CurveAnother Roof2023-10-31 | To try everything Brilliant has to offer—free—for a full 30 days, visit brilliant.org/AnotherRoof. The first 200 of you will get 20% off Brilliant’s annual premium subscription.
⬣ ABOUT ⬣ Happy Halloween! The Leibniz Formula -- the alternating sum of the reciprocals of odd numbers -- converges on π/4. It's a bizarre result. Even more bizarre is the Witch of Agnesi, a curve with a fascinating history. In this video we marry these together, using the Witch to demonstrate why this alternating sum produces π.
This video was sponsored by Brilliant.
⬣ TIMESTAMPS ⬣ 00:00 - Introduction 03:37 - Defining the Witch 07:49 - Two Lemmas 11:56 - Witch Area Part I 13:40 - Etymology of the Witch 18:39 - Witch Area Part II 28:55 - Outro
⬣ INVESTIGATORS ⬣ Nothing for you here. Sorry!
⬣ REFERENCES ⬣ [1] P. Fermat, Œuvres de Fermat, Methodes de Quadrature, Gauthier-Villars et fils (1891). [2] G. Grandi, "Note al trattato del Galileo del moto naturale accellerato", Opera Di Galileo Galilei (in Italian), vol. III, Florence p. 393 (1728). [3] M. Agnesi, Instituzioni analitiche ad uso della gioventú (1748). [4] J. Colson, Analytical institutions, Wingrave & Rivington (1801). [5] smithsonianmag.com/science-nature/18th-century-lady-mathematician-who-changed-how-calculus-was-taught-180969078 [6] D. Struik, A Source Book in Mathematics, Cambridge, Massachusetts: Harvard University Press (1969). [7] Complete Dictionary of Scientific Biography, Charles Scribner's Sons (Vol. 1.) (2008). [8] C. Truesdell, Corrections and additions for “Maria Gaetana Agnesi”. Arch. Hist. Exact Sci. 43, 385–386 (1992). doi.org/10.1007/BF00374764 [9] P. Fanfani, Vocabolario dell'uso toscano, p. 334 (1863). [10] S. Stigler, Studies in the History of Probability and Statistics. XXXIII Cauchy and the witch of Agnesi: An historical note on the Cauchy distribution, Biometrika, Volume 61, Issue 2, August 1974, Pages 375–380, doi.org/10.1093/biomet/61.2.375 [11] T. F. Mulcrone, The Names of the Curve of Agnesi. American Mathematical Monthly, 64, 359 (1957). [12] encyclopedia.com/women/encyclopedias-almanacs-transcripts-and-maps/agnesi-maria-gaetana-1718-1799
⬣ MUSIC CREDITS ⬣ "Night Watch" by Torus. "Playfully" by V Draganov. "Ursula Bones" by Roger Gabalda. "Haunted House" by Danijel Zambo. "Graveyard Tango" by Oliver Massa. "Fairytales" by Danijel Zambo. "Cautious Optimism" by Apex Music. "The Air we Breathe" by Apex Music. "Hostage" by Richard Bodgers.Mathematician Deconstructs A Beautiful MindAnother Roof2023-10-12 | ⬣ LINKS ⬣ ⬡ PATREON: patreon.com/anotherroof ⬡ CHANNEL: youtube.com/c/AnotherRoof ⬡ WEBSITE: https://anotherroof.top ⬡ SUBREDDIT: reddit.com/r/anotherroof ⬡ TWITCH: twitch.tv/anotherroof
⬣ ABOUT ⬣ A Beautiful Mind tells the life story of John Nash. It features some mathematics, but how accurate is it? Join me as I break down these mathematical scenes to see if they hold up.
⬣ TIMESTAMPS ⬣ 00:00 - Introduction 01:51 - Game Theory 05:51 - A Game Theory Application 09:19 - Other Bits of Mathematics 11:57 - Reviewing the Film
⬣ CREDITS ⬣ Music by Danjel Zambo. Intro Music by Aaron Paul Low.
⬣ ABOUT ⬣ The concept of symmetry can be formalised through the study of groups. Groups can be constructed from simple groups, and during an incredible effort throughout the 20th century, all simple groups have been classified. But the classification is messy -- there are several infinite families and then 26 left-over groups which don't fit any of the patterns. In this video, we explore some of these so-called Sporadic Groups and why they exist.
⬣ TIMESTAMPS ⬣ 00:00 - Intro and Housekeeping 01:56 - Introduction to Group Theory 05:13 - Classifying Groups 10:04 - Transitive Groups 15:06 - M24 19:20 - The Mathieu Family 26:29 - Why Sporadic Groups Exist
⬣ INVESTIGATORS ⬣ Nothing for you here. Sorry!
⬣ REFERENCES ⬣ [1] É Mathieu, Sur la fonction cinq fois transitive de 24 quantitiés. Journal de mathématiques pures et appliquées 18 (1873) pp. 25-46. [2] E Witt, Die 5-fach transitiven Gruppen von Mathieu. Abhandlungen aus dem Mathematischen Seminar der Universität Hamburg, 12: 256–264 [3] P Cameron, Projective and polar spaces. (1992) University of London, Queen Mary and Westfield College. [4] P Cameron, Permtation groups. (1999) London Mathematical Society Student Texts, Cambridge University Press. [5] W Burnside, Theory of Groups of Finite Order. (1911) Cambridge University P [6] mathshistory.st-andrews.ac.uk/Biographies/Mathieu_Emile [7] P Duhem, Emile Mathieu, his life and works. Bull. New York Math. Soc. 1(7): 156-168 (April 1892). [8] Aimo Tietäväinen, On the nonexistence of perfect codes over finite fields. SIAM Journal on Applied Mathematics, 24(1), 88–96.
⬣ CREDITS ⬣ Music by Danjel Zambo. Intro music by Tobias Voigt.
⬣ ABOUT ⬣ The (extended) Golay code is a beautiful structure that has many practical uses and also rears its head in areas of pure mathematics. It makes for an efficient means of communicating across the vast distances in space, while also popping up in the study of sporadic simple groups.
⬣ TIMESTAMPS ⬣ 00:00 - Introduction and Housekeeping 03:52 - ISBN Error Detection 07:00 - Hamming Codes, Error Correction, and Linearity 19:45 - Weight and Distance in Linear Codes 25:17 - Golay Code 43:38 - Connection to S(5,8,24) 49:03 - Outro
⬣ INVESTIGATORS ⬣ Nothing for you here. Sorry!
⬣ REFERENCES ⬣ [1] E. R. Berlekamp. Key Papers in the Development of Coding Theory. IEEE Press (1974). [2] M. Golay. Notes on Digital Coding. Proc. IRE, vol 37, p657 (1949). [3] T. M. Thompson. From Error-Correcting Codes through Sphere Packings to Simple Groups, The Carus Mathematical Monographs (#21), Mathematical Association of America, pp. 16–17 (1983).
⬣ CREDITS ⬣ Music by Danjel Zambo. Brief excerpt from “Moon Men” by Jake Chudnow.
⬣ ABOUT ⬣ I have loved this diagram ever since I first saw it on the coffee cup of one of my lecturers / colleagues. But I was shocked to discover that its extraordinary properties weren’t very well-known! In this video, I build up some theory necessary to understand the MOG, then demonstrate how to use it.
⬣ TIMESTAMPS ⬣ 00:00 - Intro 02:49 - Motivation 07:14 - Steiner Systems 18:23 - Three Big Questions 29:21 - S(5,8,24) and the MOG 44:47 - Outro
⬣ HINT ⬣ Why might S(2,3,10) be impossible to construct? Try and prove the following lemma: If S(t,k,n) exists, then S(t-1,k-1,n-1) exists. Then use the contrapositive of this statement together with what we know about the number of blocks. In fact, one can prove that: If S(t,k,n) exists, then S(t-m,k-m,n-m) exists for integer m such that t-m is non-negative.
⬣ INVESTIGATORS ⬣ Nothing for you here. Sorry!
⬣ REFERENCES ⬣ R. T. Curtis, A New Combinatorial Approach to M24. Math. Proc. Camb. Phil. Soc. (1976), 79, 25. J. H. Conway and N. J. A. Sloane, Sphere Packings, Lattices, and Groups. Springer Science (1991).
Contact me via my personal website if you’d like to hire me as a tutor: ⬡ drmcgaw.co.uk
⬣ ABOUT ⬣ All my life, I have been obsessed with a counting puzzle I came up with as a child. Turns out, I’m not the first to think about it. Known as Hertzsprung’s Problem or the n-kings problem, I present an elementary proof of the general formula given by Morton Abramson and William Moser.
⬣ TIMESTAMPS ⬣ 00:00:00 - Introduction and History 00:11:04 - Overview 00:17:14 - Stars & Bars 00:23:44 - Inclusion-Exclusion Principle 00:29:31 - Pascal’s Triangle 00:33:27 - Forbidden Pair Options Part 1 00:43:51 - Forbidden Pair Options Part 2 00:51:55 - Number of Permutations 00:55:52 - Putting it all Together 01:03:22 - A Cleaner Way? 01:06:40 - Outro
⬣ INVESTIGATORS ⬣ Nothing for you in this one. Sorry!
⬣ REFERENCES ⬣ M Abramson and W Moser, Combinations, Successions and the n-Kings Problem. Mathematics Magazine, Vol. 39, No. 5 (Nov., 1966), pp. 269-273.
Contact me via my personal website if you’d like to hire me as a tutor: ⬡ drmcgaw.co.uk
⬣ ABOUT ⬣ The word "deduction" is often used synonymously with "reach a conclusion." But deduction is much more specific than that. Watch to learn about the three types of reasoning -- deduction, induction, and abduction -- and find out which method Sherlock Holmes actually employs.
How were tangents derived before calculus? And why did Descartes and Fermat, two of history’s more renowned mathematicians, hate each other? Watch to explore their methods to solve the tangent line problem and the origins of their bitter rivalry.
⬣ TIMESTAMPS ⬣ Intro - 00:00 Descartes and his Circle Method - 03:34 Fermat and his Adequality Method - 15:13 Rivalry - 29:09 Folium of Descartes - 31:26 Conclusion - 42:18 Outro - 46:08
⬣ CORRECTIONS ⬣ In some sources, “Discourse on Method” is described as a work of three essays. Elsewhere, it is described as the introductory work to those three essays.
⬣ INVESTIGATORS ⬣ Are you still out there? Check my logic video for an update!
⬣ REFERENCES ⬣ [1] R. Descartes, La Geometrie, Trans. David Eugene Smith and Marcia L. Latham. Open Court Publishing Company: La Salle. (1952), pp. 95–112. [2] Selected Correspondence of Descartes, Jonathan Bennett 2017: earlymoderntexts.com/assets/pdfs/descartes1619.pdf [2a] to Mersenne, end of xii.1637, paraphrased. [2b] Fermat to Mersenne, iv or v 1637. [2c] to Morin, 13,vii.1638. [2d] to Mersenne 27.vii.1638 [2e] to Mersenne, ix.1641. [2f] against Fermat, 1.iii.1638. [2g] to Mersenne, 27.v.1638. [2h] to Mersenne, xii.1638. Huge thank you to Hal Hellman and his excellent “Great Feuds in Mathematics” for compiling many of the sources used in this video. [3] Hal Hellman, Great Feuds in Mathematics, 2006. [4] D. E. Smith, A Source Book in Mathematics, McGraw-Hill, 1929, pp. 389-96. [5] Fermat to Mersenne, December 1637; Fermat Oeuvres, vol. 2, p. 116. Translated by Daniel Curtin. [6] Fermat to Mersenne, February 1638; Fermat Oeuvres, vol. 2, pp. 132-33. Translated by Daniel Curtin. [7] G. F. Simmons, Calculus Gems, 1992 p. 101. [8] Fermat to Clerselier, March 10, 1658. Translated by elucidation by James Nicholson. [9] J. D. Nicholson, as detailed in Hal Hellman, "Great Feuds in Mathematics" 2006. [10] L. T. More, Isaac Newton, Scribner’s 1934 p. 185.
Symbolic logic looks intimidating, combining familiar symbols like equality and inclusion with lesser-known backwards E’s and upside down A’s. But with a bit of guidance, anyone can understand the meaning of these symbols and interpret logical statements.
00:00 - Intro 03:07 - Or, And, Not 06:28 - Implication 16:39 - Quantifiers 26:26 - Outro
INVESTIGATORS
ftfftttftf is not the slug you are looking for.
CORRECTIONS
*Propositions vs predicates: So that I didn’t overwhelm the viewer I stuck to just using “proposition” throughout. I know this isn’t strictly correct as many of the statements involving variables are actually prediates.
**For some reason when recording I had it in my head that ‘n’ was a British thing when it is widely used throughout the Anglosphere and beyond.
***Slip of the tongue that kind of undermines my point — the converse of Legrange’s Theorem would be “H is a subset with cardiality dividing |G| ⇒ H is a subgroup of G."
****Another slip of the tongue that undermines the point — we are showing that whenever x is NOT zero, it has a reciprocal y=1/x.
Okay, we all know 1 isn’t prime. But it wasn’t always that way. It also wasn’t always considered to be a number at all. Join me on a deep dive into mathematical history to see how our concepts of numbers and primes changed over time.
A huge thank you to my patrons for keeping the channel alive. Please consider supporting me by following the link above!
An enormous thank you to Chris Caldwell et al. for their compilation of sources regarding the history of 1 as a prime. Their work is much more thorough and extensive than my video and covers many, many more examples of 1 defined as prime or otherwise. My video is intended as a rough narrative through line regarding the broad(ish) consensus regarding the status of 1. Having such an extensive list of sources was really helpful when writing. You can find their article here:
Caldwell, Chris K. et al. “The History of the Primality of One: A Selection of Sources.” Journal of integer sequences 15.9 (2012).
All music by Danijel Zambo.
TIMESTAMPS:
00:00 - Intro 01:20 - Antiquity 09:17 - Medieval 13:50 - Modern 23:59 - Outro
REFERENCES
[1] - Euclid. The Thirteen Books of The Elements, Vol. 2 Books III-IX. Translated by Heiberg. Dover Books on Mathematics, 1956.
[2] - Martianus Capella. et al. Martianus Capella and the Seven Liberal Arts. Vol.2, The Marriage of Philology and Mercury. New York ;: Columbia University Press, 1977.
[3] - Isidore, and Stephen A. Barney. The Etymologies of Isidore of Seville. Cambridge: Cambridge University Press, 2006.
[4] - Khuwārizmĭ, Mu.hammad ibn Mūsá, Robert, and Barnabas. Hughes. Robert of Chester’s Latin translation of al-Khwārizmĭ’s al-Jabr : a new critical edition. Stuttgart: Franz Steiner, 1989.
[5] - Stevin, S. The Principal Works of Simon Stevin. Vol.2B. Mathematics. C.V. Swets & Zeitlinger, 1958.
[6] - Morland, Samuel. The Description and Use of Two Arithmetick Instruments : Together with a Short Treatise, Explaining and Demonstrating the Ordinary Operations of Arithmetick, as Likewise a Perpetual Almanack and Several Useful Tables : Presented to His Most Excellent Majesty Charles II ... London: Printed and are to be sold by Moses Pitt ..., 1673.
[7] - Moxon, Joseph, and Henry Coley. Mathematicks Made Easie, or, A Mathematical Dictionary ... The second edition, corrected and much enlarged by Hen. Coley ... London: Printed for J. Moxon ..., 1692.
[8] - Rahn, Johann Heinrich, Thomas Brancker, and John Pell. An Introduction to Algebra. London: Printed by W.G. for Moses Pitt ..., 1668.
[9] - C. Goldbach, Letter to Euler dated 7 June 1742. Correspondance math´ematique et physique de quelques c´elebres geometres du XVIIIeme, siecle by P.-H. Fuss, Vol. I, pp. 125–129, Academie Imperiale des Sciences, St.-Petersbourg, 1843.
[10] - J. G. Krüger, Gedancken von der Algebra, nebst den Primzahlen von 1 bis 1000000, Lüderwalds Buchhandlung, Halle, 1746.
[11] - Euler, Leonhard, and John Hewlett. Elements of Algebra. Trans. John Hewlett. Cambridge: Cambridge University Press, 2009.
[12] - Gauss, Carl Friedrich et al. Disquisitiones Arithmeticae. New York: Springer-Verlag, 1986. Print.
[13] - Gregory, Olinthus. Mathematics for Practical Men : Being a Common-Place Book of Pure and Mixed Mathematics, Designed Chiefly for the Use of Civil Engineers, Architects and Surveyors. 4th ed / rev. and enl., by Henry Law. London: J. Weale, 1862.
[14] - Hardy, G. H. (Godfrey Harold). A Course of Pure Mathematics. 6th ed. Cambridge Eng: The University Press, 1933.
[15] - Hardy, G. H. (Godfrey Harold). A Course of Pure Mathematics. Centenary ed. Cambridge: Cambridge University Press, 2008.
[16] - Sagan, C. Contact. Simon and Schuster, 1985.
[17] - J. B. Andreasen, L.-A. T. Spalding, and E. Ortiz, FTCE: Elementary Education K-6, Cliffs Notes, Wiley, Hoboken, NJ, 2010.Maths: Discovered or Invented? Do Computer-Aided Proofs Have Value? 10K Q&AAnother Roof2022-10-06 | Huge thank you to everyone who submitted questions -- this was a fun and relaxing video to make. Hopefully my views aren't too contentious.
00:00 - Intro 00:44 - Surreal Numbers? 01:54 - Why YouTube? 03:59 - Negative Bases? 04:17 - Do I Make the Props? 06:08 - Axiom of Choice? 08:24 - Film, Music, Book? 11:47 - Why Bricks? 12:37 - How to Pronounce Gödel? 13:12 - Favourite Theorem? 17:17 - Do Computer-Assisted Proofs Have Value? 21:10 - What's my PhD Thesis? 23:37 - Favourite Type of Graph? 24:12 - Channel Plans? 24:57 - Favourite Number(s)? 25:54 - Is Mathematics Invented or Discovered? 29:10 - OutroDefining Every Number EverAnother Roof2022-09-26 | PATREON: patreon.com/anotherroof CHANNEL: youtube.com/c/AnotherRoof WEBSITE: https://anotherroof.top SUBREDDIT: reddit.com/r/anotherroof
Visit my subreddit to ask questions — if I get enough I’ll make a 10K Q&A video.
Over my previous three videos, we defined the natural numbers 0, 1, 2, 3, and so on, then explored how to use them to count and carry out basic arithmetic. What about the negatives? Fractions? Irrationals? In this video we’ll develop our understanding of numbers to include all these and more.
An enormous thank you to my Patrons. This one took me a while to make but you had my back every step of the way and encouraged me to take my time and make the video the best I can make it. If you'd like to support me and gain access to progress updates, bloopers, the Discord server where we can hang out, and have your name in the credits, please consider supporting me (link above)!
NOTES: https://anotherroof.top/s/Video4Notes.pdf
This video is very long. Certain details had to be cut for the sake of pacing, but you can find some of those details in the notes above. You might also find other things of interest in there. I can confirm that everything you need is in the final portion of the video. And you'll need this: anotherroof.top/taking-advice
Timestamps:
0:00:00 - Intro 0:01:33 - The Plan 0:03:33 - Preparation 1/3: New Axioms 0:05:42 - Preparation 2/3: Cartesian Products 0:10:49 - Preparation 3/3: Relations and Partitions 0:22:39 - Short Break 0:23:10 - Integers 0:39:01 - Rationals 0:55:10 - Real Numbers 1:12:23 - Complex Numbers 1:17:41 - Credits and Q&A
Comments and corrections:
-There is some audio clipping in the video. Sorry about that. I tried a new microphone placement and only realised the issue long after shooting the whole video. Tried to fix it in post to no avail. Hopefully it isn’t too distracting!
As previously explored, we can define the natural numbers in terms of sets. We can even use them to count. But how are operations like addition and multiplication defined? Along with a crash-course in proof by induction, we'll define these operations in this video and prove that they possess all the lovely properties with which we are familiar.
Huge thank you to my Patrons. Without you, I wouldn't have the confidence to make YouTube part of my career may not have continued making videos. If you'd like to support me and gain access to progress updates, bloopers, the Discord server where we can hang out, and have your name in the credits, please consider supporting me (link above)!
Join the subreddit! Thinking of doing a 10K subscriber Q&A video so head on over there and submit your questions, be they personal, mathematical, pedagogical, or whatever. Reddit: reddit.com/r/anotherroof
*It is sufficient to define addition without the n+1:=S(n) part. However, I made the pedagogical choice to include this -- it's less efficient but more intuitive for the uninitiated, in my opinion.
**The base cases of our inductions should deal with the n=0 case, as then the n=1 case is true by virtue of "true for k ⇒ true for (k+1)" where k=0. However, the n=0 case is always completely trivial so I decided to make my base cases at n=1 so that viewers less experienced with proof by induction get to see more "work" being done and get a feel for how to complete proofs by appealing to axioms. Let's just go ahead and assume we've proved the n=0 case separately in all proofs!
***I misspeak here: We are proving that if a given number k commutes with *a* then the next number commutes with *a*. Apologies!
****Psst, it's me, Yellow T-Shirt Alex, put the solution in the website slug. You'll also need those numbers I told you to keep safe!
Hidden in this question is a lot of fascinating mathematics. Puzzle through and gain a greater appreciation for the simple act of counting. In this video, we will use our axioms to demonstrate how to construct functions and how we use them to robustly define counting. Last time, we defined the axioms of ZF and I highly recommend you watch that video first. Video making is something I’ve wanted to get into for a while.
Solution is what you seek? Will you succeed? Need to grow my channel. You can help by sharing my videos. To all those who watched and shared my last video, thank you! Write to me through the link in my website to get in touch. Special thanks to all those who supported me on Buy Me a Coffee! Comment below with any feedback you think will improve my content.
If you’d like to see more please consider supporting me on Patreon. Already, I’ve had lots of great feedback and really appreciate all the nice words. Solved — that’s how I’d like to feel about the video-making process but I’m not there yet. Try as I might, these videos take a really long time for me to make. Reverse engineering the mathematics to make it accessible to a wide audience is a slow process. Slug pace, some might say.
*Correction: As stated, I show the 1-set, {{}}, where in fact I should show the 2-set {{},{{}}}.
**I have no idea why my footage is so blurry from around the 26-minute mark. Apologies!
All music by Danijel Zambo.What IS a Number? As Explained by a MathematicianAnother Roof2022-06-29 | NEXT VIDEO IN SERIES youtube.com/watch?v=QO9a7h87DbA See how we develop even more concepts from this mathematical foundation.
Ever wondered how numbers are actually defined? In this video, you'll learn the most common way it's done by mathematicians.
MY PATREON IS NOW LIVE! Buy me a coffee if you like, but the best way to support me now is on Patreon, where I'll post updates, sneak peaks, bloopers, and my signing up you'll have your name in the credits of every video!
My website may be a good place to start if you're confused...
#SoME2
00:00 - Intro 02:19 - Motivation 04:12 - Physical Units: An Analogy 08:26 - First Attempt 10:39 - The Perils of Intuition 12:40 - Definition in Principle 15:38 - Sets and Russell's Paradox 23:44 - Rules of Sets 31:46 - Constructing the Numbers 38:25 - Cake 38:29 - Closing Remarks
*Galileo's Paradox: In his final book, which bears the catchy title, "...," Galileo discusses the size of the set of natural numbers versus that of the set of square numbers (not even numbers, as in my video, but the point is the same). It's written as a dialogue, not as a letter as I erroneously claimed.
**Formulations of ZF: There are several equivalent ways of formulating ZF set theory. Some have that the empty set exists as an axiom, but not all. Others prove the existence of the empty set by using the axiom of infinity then the axiom of subsets, and others argue similarly to how I argue in that in first-order logic, something exists. The point is, I shouldn't have claimed that the axiom of the empty set is always part of ZF.
Help me on my maths mission to raise £2000 for Refuge, a charity providing support for victims of domestic violence. I'm a UK-based maths teacher and PhD graduate. Lockdown was relatively easy for me but hell for many. If you are unable to give, please enjoy the show, ask a question in the comments, and share!Maths Teacher Does 24 Exams in 24 Hours (Part 2/3)Another Roof2022-04-10 | PART 3 HERE: youtu.be/q4zWF0Qpczg
Help me on my maths mission to raise £2000 for Refuge, a charity providing support for victims of domestic violence. I'm a UK-based maths teacher and PhD graduate. Lockdown was relatively easy for me but hell for many. If you are unable to give, please enjoy the show, ask a question in the comments, and share!Maths Teacher Does 24 Exams in 24 Hours (Part 1/3)Another Roof2022-04-09 | PART 2 HERE: youtu.be/T9h55waUth8
Help me on my maths mission to raise £2000 for Refuge, a charity providing support for victims of domestic violence. I'm a UK-based maths teacher and PhD graduate. Lockdown was relatively easy for me but hell for many. If you are unable to give, please enjoy the show, ask a question in the comments, and share!