https://aussiescience.com/silicon/why-can-sand-think/https://aussiescience.com/thumbs/silicon/why-can-sand-think-1280.webpWhy can sand think?Uses energy bands to explain why copper conducts and glass doesn't, and why silicon is really an insulator with a narrow gap. Follows silicon from quartz to a single crystal ten or eleven nines pure, and shows why it replaced germanium, whose leakage ran away as it warmed.https://www.youtube-nocookie.com/embed/umoeUS-qdRU7412026-10-04T00:52:28+00:00yesno https://aussiescience.com/silicon/doping/https://aussiescience.com/thumbs/silicon/doping-1280.webpDoping: a few wrong atoms on purposeExplains how a phosphorus atom brings a loose spare electron and a boron atom leaves a hole, making n-type and p-type silicon. Covers Russell Ohl's cracked rod at Bell Labs in 1940, why one dopant atom per billion matters so much, and how ion implantation puts atoms in place.https://www.youtube-nocookie.com/embed/nuTmrlDrCQo6182026-10-04T00:43:59+00:00yesno https://aussiescience.com/silicon/diode-and-rectifier/https://aussiescience.com/thumbs/silicon/diode-and-rectifier-1280.webpThe one-way street: diodes and rectifiersExplains the depletion region, the hill of locked charge where p meets n, and why silicon's comes out near 0.7 volts. Shows how forward and reverse bias make a one-way valve, how four diodes and a capacitor turn mains AC into one-way current, and why gallium arsenide glows while silicon stays dark.https://www.youtube-nocookie.com/embed/VY2kwwl3FMU6752026-10-04T00:45:30+00:00yesno https://aussiescience.com/silicon/1947/https://aussiescience.com/thumbs/silicon/1947-1280.webp1947: how Bell Labs stumbled into the transistorWilliam Shockley's field-effect amplifier failed, and John Bardeen traced the problem to electrons stuck in surface states. Walter Brattain's gold contacts on germanium then amplified about a hundred times by injecting holes. Also covers Shockley's junction transistor and the 1956 Nobel Prize.https://www.youtube-nocookie.com/embed/6w69YGqgtbI6492026-10-04T00:42:29+00:00yesno https://aussiescience.com/silicon/switch-and-amplifier/https://aussiescience.com/thumbs/silicon/switch-and-amplifier-1280.webpSwitch and amplifier: BJT vs MOSFETCompares the two kinds of transistor. The bipolar junction transistor needs a steady base current, while the MOSFET's insulated gate summons a channel and draws almost nothing at rest. Covers Atalla and Kahng's 1959 device, Dennard scaling, and why, by one estimate, 99.9 per cent of transistors shipped are MOS.https://www.youtube-nocookie.com/embed/M7QMJjb0ESs6672026-10-04T00:47:40+00:00yesno https://aussiescience.com/silicon/integrated-circuit/https://aussiescience.com/thumbs/silicon/integrated-circuit-1280.webpThe integrated circuit: printing circuits with lightCovers the tyranny of numbers, Jack Kilby's 1958 germanium chip with hand-bonded gold wires, and how Jean Hoerni's planar process let Robert Noyce put the wiring on the oxide. Walks through photolithography layer by layer, and explains why big dies and dust push up the cost of each good chip.https://www.youtube-nocookie.com/embed/UaPDw0oBNQo6812026-10-04T00:48:59+00:00yesno https://aussiescience.com/silicon/logic-from-switches/https://aussiescience.com/thumbs/silicon/logic-from-switches-1280.webpLogic from switches: gates, CMOS and the 555Shows how pairs of n-type and p-type transistors make CMOS gates, and why NAND gates alone can build any logic. Covers George Boole, Claude Shannon's relays, binary adders, why idle CMOS draws almost no power, the clock, the flip-flop as one bit of memory, and Hans Camenzind's 555 timer.https://www.youtube-nocookie.com/embed/eGG2-SgumO86812026-10-04T00:55:47+00:00yesno https://aussiescience.com/silicon/memory/https://aussiescience.com/thumbs/silicon/memory-1280.webpHow silicon remembers: RAM, ROM and flashExplains static RAM's six-transistor loop, Robert Dennard's one-transistor DRAM cell that leaks and is refreshed roughly every 64 milliseconds, and flash memory's floating gate sealed in glass. Ends with why flash wears out, and why computers stack fast SRAM, then DRAM, then flash.https://www.youtube-nocookie.com/embed/ca88XYhqrQE6822026-10-04T00:24:42+00:00yesno https://aussiescience.com/silicon/special-purpose-silicon/https://aussiescience.com/thumbs/silicon/special-purpose-silicon-1280.webpCPU vs ASIC vs FPGA vs GPUExplains why a processor spends far more energy fetching and decoding each instruction than doing the sum, and how ASICs, FPGAs and GPUs trade flexibility for efficiency. Follows Bitcoin mining's move to ASICs, AlexNet's 2012 win on two graphics cards, and Google's TPU.https://www.youtube-nocookie.com/embed/WylSazccP6k7082026-10-04T00:26:17+00:00yesno https://aussiescience.com/silicon/data-centres-and-next/https://aussiescience.com/thumbs/silicon/data-centres-and-next-1280.webpData centres and what's nextExplains why heat is now the limit: leakage stopped voltages falling, Dennard scaling broke around 2006 and clock speeds stalled at a few gigahertz. Then covers the industry's workarounds, from extreme ultraviolet light made by blasting tin droplets to chiplets, wide-gap materials and silicon photonics.https://www.youtube-nocookie.com/embed/4yx35SoV-UI6952026-10-04T00:27:32+00:00yesno https://aussiescience.com/australian-science/wifi/https://aussiescience.com/thumbs/australian-science/wifi-1280.webpWi-Fi: how CSIRO beat the echoExplains how indoor echoes cap wireless speed, and how CSIRO's 1992 patent beat them by splitting data across many slow lanes, with error correction and interleaving. Separates what came from Bell Labs and the IEEE, and follows the US lawsuits, with licence income CSIRO puts at around 430 million.https://www.youtube-nocookie.com/embed/DAKWM8ZGJ8c7202026-10-04T03:04:36+00:00yesno https://aussiescience.com/australian-science/black-box/https://aussiescience.com/thumbs/australian-science/black-box-1280.webpThe black box: David Warren's flight recorderFollows the 1950s Comet crashes, which left no survivors to explain them, and fuel chemist David Warren's 1954 memo proposing a wire loop that keeps the last two minutes of cockpit talk. Covers years of official reluctance, the 1958 visit that took it to London, and how modern recorders survive impact and fire.https://www.youtube-nocookie.com/embed/7Kx2osE3UXI6792026-10-04T02:53:15+00:00yesno https://aussiescience.com/australian-science/cochlear-implant/https://aussiescience.com/thumbs/australian-science/cochlear-implant-1280.webpThe bionic ear: Graeme Clark's cochlear implantExplains how the cochlea maps pitch to place, why a hearing aid can't help once hair cells are gone, and how Graeme Clark's Melbourne team built an electrode that slides round the spiral and a speech code that worked. Credits the earlier Paris and Vienna implants, and notes objections from many in the Deaf community.https://www.youtube-nocookie.com/embed/MWmKxAY8vNM6822026-10-04T02:54:40+00:00yesno https://aussiescience.com/australian-science/penicillin/https://aussiescience.com/thumbs/australian-science/penicillin-1280.webpPenicillin: from Fleming's mould to a medicineExplains why Fleming's 1928 discovery stalled, and how Howard Florey's Oxford team, including Ernst Chain and Norman Heatley, extracted penicillin and proved it in eight mice in 1940, then grew it in bedpans and pottery. Also covers how it bursts bacteria, and how resistance appeared almost at once.https://www.youtube-nocookie.com/embed/nMHRYz7O6z87282026-10-04T02:56:11+00:00yesno https://aussiescience.com/australian-science/ultrasound/https://aussiescience.com/thumbs/australian-science/ultrasound-1280.webpSeeing with sound: Australia's ultrasound pioneersExplains how echo timing gives depth, and why higher frequencies show finer detail but reach less deep. Credits the overseas pioneers, then shows how the Sydney group of George Kossoff and William Garrett developed grey scale, which keeps the faint echoes from inside organs that earlier screens threw away.https://www.youtube-nocookie.com/embed/MVAdusrsAV47222026-10-04T02:57:39+00:00yesno https://aussiescience.com/australian-science/stomach-ulcers/https://aussiescience.com/thumbs/australian-science/stomach-ulcers-1280.webpThe doctor who drank bacteria: Marshall, Warren and ulcersRobin Warren spotted spiral bacteria in stomach biopsies in 1979, and Barry Marshall only got them to grow after plates sat over Easter 1982. Explains how Helicobacter survives acid, what Marshall's 1984 drink did and didn't prove, and how trials changed minds before the 2005 Nobel Prize.https://www.youtube-nocookie.com/embed/Hldnkjd444A6962026-10-04T02:58:50+00:00yesno https://aussiescience.com/australian-science/hpv-vaccine/https://aussiescience.com/thumbs/australian-science/hpv-vaccine-1280.webpA vaccine against cancer: Frazer, Zhou and HPVExplains how HPV's E6 and E7 proteins disable a cell's brakes, and why the vaccine had to be an empty shell. Follows Ian Frazer and Jian Zhou's 1991 particles in Brisbane, the US patent case they won in 2007, and the evidence so far on warts, infections and cervical cancer.https://www.youtube-nocookie.com/embed/XJd7298suvg7272026-10-04T03:00:03+00:00yesno https://aussiescience.com/australian-science/spray-on-skin/https://aussiescience.com/thumbs/australian-science/spray-on-skin-1280.webpSpray-on skin: Fiona Wood and Marie StonerExplains how shallow wounds heal from hair follicles, and why lab-grown skin sheets took at least three weeks. Follows Fiona Wood and Marie Stoner's spray of a patient's own cells, its use after the 2002 Bali bombings, and what trials of ReCell do and don't show.https://www.youtube-nocookie.com/embed/WdNODt_HRew6742026-10-04T03:00:59+00:00yesno https://aussiescience.com/australian-science/polymer-banknotes/https://aussiescience.com/thumbs/australian-science/polymer-banknotes-1280.webpPlastic money: how Australia made polymer banknotesStarts with the 1966 Times Bakery forgeries and the 1968 Thredbo meeting, then explains how a diffraction grating defeats a camera and why it needs smooth plastic film. Follows David Solomon's CSIRO team to the 1988 note, forgery rates since, and the Securency bribery case.https://www.youtube-nocookie.com/embed/a_k3vP_gT646672026-10-04T03:01:54+00:00yesno https://aussiescience.com/australian-science/parkes/https://aussiescience.com/thumbs/australian-science/parkes-1280.webpThe Dish: how Parkes helped show the Moon landingExplains how a parabolic dish collects and focuses a faint signal, then sorts out who carried which minutes: Honeysuckle Creek showed the first step, Parkes nearly all the rest, and Goldstone the sound. Also covers what The Dish got wrong, and Parkes' work on pulsars and fast radio bursts.https://www.youtube-nocookie.com/embed/2OcxoOt610I6782026-10-04T02:51:11+00:00yesno https://aussiescience.com/maths-puzzles/zero/https://aussiescience.com/thumbs/maths-puzzles/zero-1280.webpWhat is zero, and why did it take so long to invent?Separates zero's two jobs, a placeholder for an empty column and a number in its own right. Traces it through Babylon, the Maya, a dot carved in Cambodia in 683 and Brahmagupta's rules of 628, and explains why dividing by zero has no answer.https://www.youtube-nocookie.com/embed/qmKGz0kmMAU7112026-10-04T03:17:47+00:00yesno https://aussiescience.com/maths-puzzles/infinity/https://aussiescience.com/thumbs/maths-puzzles/infinity-1280.webpWhat is infinity, and can one infinity be bigger than another?Contrasts two ways of comparing size, counting and pairing, and follows the idea from Aristotle and Galileo to Hilbert's hotel and Georg Cantor. Explains the diagonal argument showing the decimals can't be listed, why there's no largest infinity, and the open continuum hypothesis.https://www.youtube-nocookie.com/embed/ttzvQRexh1k6912026-10-04T03:19:45+00:00yesno https://aussiescience.com/maths-puzzles/point-nine-nine-nine/https://aussiescience.com/thumbs/maths-puzzles/point-nine-nine-nine-1280.webpDoes 0.999… really equal 1?Tests the usual arguments, one third times three and ten x minus x, and shows they assume what they set out to prove. Follows endless decimals from Simon Stevin to Cauchy's limits, Weierstrass and Dedekind, and explains why the three dots name a limit that is exactly one.https://www.youtube-nocookie.com/embed/_0xum-DuYyM6822026-10-04T04:07:21+00:00yesno https://aussiescience.com/maths-puzzles/monty-hall/https://aussiescience.com/thumbs/maths-puzzles/monty-hall-1280.webpShould you switch doors?Plays out every game to show why switching wins two times in three, and uses Bayes' theorem to explain how the host's knowledge shifts the odds. Covers Marilyn vos Savant's 1990 column and the angry letters, and why a host who opens a door at random leaves it fifty-fifty.https://www.youtube-nocookie.com/embed/IMfGPAaQvFM6452026-10-04T04:09:20+00:00yesno https://aussiescience.com/maths-puzzles/birthday-paradox/https://aussiescience.com/thumbs/maths-puzzles/birthday-paradox-1280.webpWhy do 23 people probably share a birthday?Explains why 23 people make 253 pairs, and why gut instinct only counts the pairs that include you. Works through the exact 50.7 per cent, checks it against real Australian and US birth data, untangles the credit between Davenport and von Mises, and shows how the same maths drives attacks on hashes.https://www.youtube-nocookie.com/embed/NJe3-2XtrwU6822026-10-04T04:13:03+00:00yesno https://aussiescience.com/maths-puzzles/primes-and-rsa/https://aussiescience.com/thumbs/maths-puzzles/primes-and-rsa-1280.webpWhy do prime numbers keep your bank account safe?Explains why multiplying primes is easy but factoring the product seems hard, and works through RSA with toy keys on a 33-hour clock. Covers Diffie and Hellman, the MIT trio and GCHQ's secret earlier version, what TLS 1.3 actually uses, and the move to post-quantum locks.https://www.youtube-nocookie.com/embed/LND7q17alCU7132026-10-04T03:22:09+00:00yesno https://aussiescience.com/maths-puzzles/pi/https://aussiescience.com/thumbs/maths-puzzles/pi-1280.webpWhy does pi never end?Explains why pi is the same for every circle, and follows the hunt for it from Archimedes' polygon cage to Liu Hui, Zu Chongzhi and Madhava's infinite series. Shows why Lambert's proof makes pi irrational, why Lindemann's 1882 result rules out squaring the circle, and what the Indiana pi bill said.https://www.youtube-nocookie.com/embed/YhVinl9DBAA7102026-10-04T04:05:58+00:00yesno https://aussiescience.com/maths-puzzles/zeno/https://aussiescience.com/thumbs/maths-puzzles/zeno-1280.webpHow did Achilles ever catch the tortoise?Lays out Zeno's arguments as Aristotle reported them, then shows why infinitely many shrinking steps can add up to a finite total. Works through Achilles' race to eleven and a ninth seconds, contrasts the harmonic series that never settles, and explains how the idea of a limit answers the arrow.https://www.youtube-nocookie.com/embed/aFNPGv_pIL86622026-10-04T04:05:03+00:00yesno https://aussiescience.com/maths-puzzles/graph-theory/https://aussiescience.com/thumbs/maths-puzzles/graph-theory-1280.webpHow did seven bridges start the maths behind Google Maps?Explains Leonhard Euler's 1735 proof that the Königsberg walk is impossible: every place passed through uses bridges in pairs, and all four had an odd count. Follows that idea into graph theory, Hamilton's hard routes, Dijkstra's shortest-path method and the shortcuts route planners use today.https://www.youtube-nocookie.com/embed/60pDlfw_M8U6582026-10-04T04:04:16+00:00yesno https://aussiescience.com/maths-puzzles/godel/https://aussiescience.com/thumbs/maths-puzzles/godel-1280.webpCan maths prove everything?Explains what a formal proof is, Hilbert's hope for a complete and consistent mathematics, and how Kurt Gödel coded sentences as numbers to build one that says it can't be proved. Sets out what the two incompleteness theorems do and don't say, Turing's halting problem, and the continuum hypothesis.https://www.youtube-nocookie.com/embed/8WUozW686aQ7162026-10-04T04:03:01+00:00yesno