Channel Title: Learning Curve Channel Description: What is Learning Curve all about? The Universe is an amazing place, and the goal of this channel is to uncover some of its secrets. I have been a science teacher for over 20 years, and I'm constantly amazed by the world and the universe around me. Having an inquisitive mind has set me on a mission to explore as many of the fantastic things I find as possible, and explain them to you. So if you have an inquisitive mind too, then make sure to subscribe and check back to find out what I've learned each week. As I always say, curiousness makes us human. <video> Fooling our brains with optical illusions Description: I’m returning to do a video on the reasons why our brains and visual systems can be pretty easily fooled by optical illusions. I always wanted this to be a 10 part series, but got way laid by quantum strangeness, but I thought I’d return to this series a couple more times to finish my 10 part series. I’ll be returning to quantum strangeness soon, but if you enjoy optical illusions then stick around and maybe go and find the other 8 videos I’ve made on the topic. We’re going to take another trip down trickery lane today and have another look at some optical illusions and see if we can explain what is going on, but before we do that if you could stare at the cross in the centre of the screen and I’ll explain what we’ll be looking at today. The illusions I’m going to cover today really look at contrast and how our brains deal with it. Let’s find out more, but before we do, I’ve just been talking and stalling for time, while you look at the picture on screen. If I change the picture, you should see something interesting. Anyway. Shall we carry on. These illusions are based on illusions on Michael Bach’s website. The link to that website is here. It is a truly excellent website. https://michaelbach.de/ot/ Chapters 0:00 Introduction 0:30 Tulips 1:05 Illusion 1 – Stepping Illusion 2:50 Explanation 1 4:35 Illusion 2 – Contrast Illusion 5:25 Explanation 2 </video> <video> How Vacuum Decay could Destroy the Universe Description: I’ve looked at some of the scariest things in the universe, from black holes, to Thorne-Zytkow objects to Magnetars, but the horror of these things all pale into insignificance when compared to the innocuously titled vacuum decay. Let’s find out more. If quantum tunnelling occurred with the Higgs field this would create a little bubble of universe where the Higgs field was at a lower energy level and therefore more stable. This bubble of stability would then cause the universe around it to undergo the same change and so on. This bubble of stability would expand throughout the universe at the speed of light, and this would not be good, well certainly not for us. This change to the Higgs field would change the laws of physics, we don’t really know what effect it might have but since the Higgs field affects the mass of particles, it may affect that. It might be something fairly minor in universal terms such as changing the mass of the neutrino but it might affect the mass of other fundamental particles. It may mean that protons and neutrons are no longer able to hold themselves together in the nuclei of atoms or even the protons and neutrons themselves may fall apart. Chapters 0:00 Introduction 0:39 What are fields? 2:26 What are particles? 2:55 Particles and fields 4:14 Particles and antiparticles 4:41 The Higgs Field 5:24 Fields and Energy 6:15 False Vacuums 7:45 Quantum Tunnelling 9:14 Vacuum Decay Credits Article containing the graph https://www.frontiersin.org/articles/10.3389/fspas.2018.00040/full Iron filings and magnet photo JanDerChemiker, CC BY 3.0 https://creativecommons.org/licenses/by/3.0, via Wikimedia Commons </video> <video> History of the Universe: What happened in the first 370,000 years Description: For anyone who hasn't watched part 1, the link is here https://youtu.be/sOezvWHof68 I’ve looked at what happened during the universes first second, and blimey it was busy. Now I want to have a look at another slice of the history of our universe, so in this video I’m going to look at what happened from 1 second to about 370,000 years. Let’s find out more. 370,000 years isn’t just some random number that I’ve picked out of the air. There is a very important reason for selecting that time, but we'll get to that later. Firstly we’ll start at time equals 1 second, and we’ve just left the hadron epoch. The very end of the hadron epoch saw an important event occurring. That is the decoupling of neutrinos. Before this time neutrinos interacted with the matter that existed in the universe, but at a time of 1s, neutrinos stopped interacting with matter. Since the neutrinos at this time no longer interacted with matter, they just started flying round the universe, and have been flying round the universe ever since. Somewhere out there, these neutrinos still exist and form what is called the neutrino background radiation, but these neutrinos are very low energy. Much lower in energy than neutrinos made today in the heart of suns. These neutrinos are out there but due to their low energy we may never discover them. Microwave Background Radiation Image Credit: NASA / WMAP Science Team Chapters 0:00 Introduction 0:30 Neutrino Decoupling 1:25 Lepton Epoch 2:15 Matter is Energy 3:45 Photon Epoch 5:20 Nucleosynthesis 6:10 Proton-Proton Chain Reaction 7:30 Energy Density 8:20 Atoms Form 8:45 The Universe Becomes Transparent </video> <video> Einstein and Mercury: How the Orbit of Mercury Proved Einstein was Right Description: The orbit of the planet Mercury is a bit strange and doesn’t act exactly as expected. This was such a problem, that we even invented another planet to account for its weird orbit. In fact it is this strangeness that provided evidence that Einstein was right all along. Let’s find out more. The orbit of Mercury doesn’t act like we expect it to, it has a rate of precession that is higher than expected. In the 19th century, astronomers even suggested that this was due to an additional planet that they named Vulcan. In fact the real reason was even more strange and due to the curvature of spacetime. This proved Einstein and his theory of general relativity correct after all. Chapters 0:00 – Introduction 0:29 – General Relativity 2:45 – Orbits and ellipses 5:00 – Precession 6:00 – The problem with Mercury 7:20 – Relativity 8:15 – Real World Applications </video> <video> kilonova: When Neutron Stars Collide Description: We all know that neutron stars are pretty extreme stellar phenomena, but what would happen if two of them ever collided? Welcome to the strange world of the kilonova. Let’s find out more. Kilonovas get their names from the fact that they are 1000 times brighter than a nova. This does mean that they are about 1 tenth to 1 hundredth the brightness of a supernova, and because of how they form they are incredibly interesting indeed. Magnetar Video https://youtu.be/jRPjgKs-aw4 Speed of light video https://youtu.be/kZZ4B8UiEGM Chapters 0:00 – Introduction 0:12 – What are Kilonovas 0:42 – Neutron star formation 1:00 – Binary pairs 2:23 – Neutron star mergers 3:18 – Kilonova 3:48 – R process 4:50 – What does a kilonova produce? 5:17 – Gravity waves 7:00 – Gravity wave detection Image Credits GRB130603 Image Credit: NASA, ESA, N. Tanvir (University of Leicester), A. Levan (University of Warwick), A. Fruchter (STScI), J. Hjorth (University of Copenhagen), R. Hounsell (STScI), K. Wiersema (University of Leicester), and R. Tunnicliffe (University of Warwick) Hubble picture of NGC 4993 with inset showing GRB 170817A over 6 days. Credit: NASA and ESA Hubble Space Telescope, NASA and ESA - https://www.nasa.gov/press-release/nasa-missions-catch-first-light-from-a-gravitational-wave-event </video> <video> History of the Universe: When did the first stars start to shine? Description: In this video, I’m going to carry on and look at what happened between 370,000 years and about 4.6 billion years ago when our sun formed. So for the first time, the universe has become transparent, so what can we see. Well not very much. And now that the universe is transparent lets hop into my time and space machine and go and have a look. If you look round, you can see an orange glow all over the place. These are photons produced during the decoupling where photons stopped interacting with matter. If we stick around for the next 3 million years or so we will see that orange glow get gradually redder and redder as the expanding universe red shifts the light waves until eventually nothing is visible. These photons haven’t gone they are now just not in the visible part of the spectrum. By the time we get to our time, these photons have become shifted so much that they are now in the microwave part of the spectrum. Link for Part 1 https://youtu.be/sOezvWHof68 Link for Part 2 https://youtu.be/2daHlx9z9Jw Chapters 0:00 Introduction 0:50 Cosmic Microwave Background Radiation 1:50 Liquid Water? 3:05 Matter & Dark Matter 5:35 The First Stars 7:10 Reionisation 8:13 Methuselah Star 8:39 The First Galaxies 9:10 Time moves more slowly 10:20 Dark Energy 11:00 Proxima Centauri Credits ESA/Hubble, CC BY 4.0 https://creativecommons.org/licenses/by/4.0, via Wikimedia Commons Andromeda Galaxy Torben Hansen, CC BY 2.0 https://creativecommons.org/licenses/by/2.0, via Wikimedia Commons </video> <video> Quarks: They Make up (a lot of) The Universe Description: Hello! I'm back!! In this video I’m going to look at Quarks, and their relationship with the matter of the universe. Ok so lets start off with matter. This is the stuff that makes up much of the visible universe. Matter is made from atoms, and atoms are made from protons and neutrons collected in the nucleus, and electrons in a sort of cloud around the nucleus. If we look more closely at the protons and neutrons, we find that they are in turn made up of even more fundamental particles called quarks, but what are quarks. Quarks are part of the standard model of particle physics, which we can see here, and there are 6 types of quark, and we call the different types flavours. The 6 flavours are, Up, down, top, bottom, strange and charm. Up, down and strange are grouped together as they are lighter, and the top, bottom and charm are grouped together as they are heavier. Demonstration of spin ½ by Lloyd Watts https://www.youtube.com/watch?v=JFSU9X11wyY My Vacuum Decay video https://youtu.be/1zDzbXbt7Hc Chapters 0:00 Introduction 0:20 What is matter? 0:55 The Standard Model of Particles 1:25 What are Quarks? 2:30 Electric Charge 3:45 Spin 5:00 Weak Force & Gravity 5:40 Strong Force 6:05 Colour Charge 7:20 Mesons 8:50 Baryons 11:30 Gluons 13:00 Valence & Sea Quarks 14:45 Tetraquarks 15:55 Pentaquarks </video> <video> The Size of the Universe: In Stages Description: I’ve looked at the very small scale of the universe, what about if I go the other way and have a look at the large scale of the universe, what is out there? Lets find out more. I’m going to start off with the SI base unit of length, the metre. I’ll try and do as many conversions to imperial units as I can, but I’ll stop once we get to light years. I’m going to go up in scale looking at both the size of objects and distances involved as we go from the metre upwards. This is also going to be my longest video to date, so bring snacks. Let’s get on shall we. So to start we have the metre. This is 3.28 feet and the standard length measurement in the SI system. It was originally defined as 1, 10 millionth of the distance from the north pole to the equator. After a number of redefinitions, it was finally defined in 1983 as the distance light travels in 1 over 299 792 458 ths of a second. In fact we’ve now set the speed of light so that any revisions of the speed of light wouldn’t change the speed of light itself, they’d alter the size of a metre. Chapters 0:00 Introduction 0:42 The Metre 3:39 1 Kilometre 6:11 1000 Kilometres 9:16 1 million Kilometres 11:39 1 Billion Kilometres 15:13 1 Trillion Kilometres 16:04 1 Light Year (roughly) 22:32 1000 Light Years 26:09 1 Million Light Years 29:58 1 Billion Light Years Dimorphos Image Credit By NASA/Johns Hopkins APL - https://www.nasa.gov/feature/dart-s-final-images-prior-to-impact (image link); original upload from https://dart.jhuapl.edu/Gallery/ (image link), Public Domain, https://commons.wikimedia.org/w/index.php?curid=123433723 Map of Tethys NASA/JPL-Caltech/Space Science Institute Map of Rhea NASA/JPL-Caltech/Space Science Institute Map of Triton NASA/JPL-Caltech/Lunar & Planetary Institute Map of the moon NASA's Scientific Visualization Studio Map of Io US Geological Survey Astrogeology Research Program Map of Ganymede A Map of GanymedeNASA (original photographies)/Björn Jónsson/Feldo, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons Jewel Bug Nebula Image NASA, ESA, and J. Kastner (RIT) https://esahubble.org/images/heic2011c/ Helix Nebula Image NASA, ESA, C.R. O'Dell (Vanderbilt University), M. Meixner and P. McCullough (STScI) Crab Nebula image By NASA, ESA, J. Hester and A. Loll (Arizona State University) - HubbleSite: gallery, release., Public Domain, https://commons.wikimedia.org/w/index.php?curid=516106 Veil Nebula Image NASA, ESA, Hubble Heritage Team https://esahubble.org/images/heic1520a/ Tarantula nebula IMAGE: NASA, ESA, CSA, STScI, Webb ERO Production Team https://webbtelescope.org/contents/media/images/2022/041/01GA76MYFN0FMKNRHGCAGGYCVQ Sextans A Image KPNO/NOIRLab/NSF/AURA Data obtained and processed by: P. Massey (Lowell Obs.), G. Jacoby, K. Olsen, & C. Smith (AURA/NSF) Image processing: T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab), M. Zamani (NSF’s NOIRLab) & D. de Martin (NSF’s NOIRLab) Triangulum Galaxy Image ESO https://www.eso.org/public/images/eso1424a/ Sombrero Galaxy Image NASA/ESA and The Hubble Heritage Team (STScI/AURA) https://esahubble.org/images/opo0328a/ Hoag’s Object By NASA and The Hubble Heritage Team (STScI/AURA); Acknowledgment: Ray A. Lucas (STScI/AURA) - http://hubblesite.org/newscenter/archive/releases/2002/21/image/a/http://antwrp.gsfc.nasa.gov/apod/ap020909.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=610534 NGC 404 (Mirach’s Ghost) Galaxy en:NASA, en:STScI, en:WikiSky, Public domain, via Wikimedia Commons M81 Image By NASA, ESA and the Hubble Heritage Team (STScI/AURA) - http://www.spacetelescope.org/images/heic0710a/ (very high quality ([cdn.spacetelescope.org/archives/images/screen//heic0710a.jpg JPEG file] 346 MB) http://hubblesite.org/newscenter/archive/releases/2007/19/image/a/ (direct link), Public Domain, https://commons.wikimedia.org/w/index.php?curid=2173424 Sloan Great Wall Image Pablo Carlos Budassi, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons GN-z11 image NASA, ESA, P. Oesch (Yale University), G. Brammer (STScI), P. van Dokkum (Yale University), and G. Illingworth (University of California, Santa Cruz) https://hubblesite.org/contents/news-releases/2016/news-2016-07.html; see also https://www.nasa.gov/feature/goddard/2016/hubble-team-breaks-cosmic-distance-record/ and http://www.spacetelescope.org/images/heic1604a/ </video> <video> The Planck Density: The Density of the Early Universe Description: I’ve looked at quite a few of the Planck base units, and I’ve even worked them out mathematically, but today I’m going to look at one of the derived units and I’ll compare it to some other things to see how big or small this is. Today then I’m going to be looking at the Planck Density. Let’s find out more. Before we start, we need to know what density is. Density is a measure of how tightly packed a material is. In other words, how much stuff is packed into a certain volume of space. To work out density then we need a formula, and units. To work out density we use the following formula, density and that is denoted by the greek letter rho equals mass divided by volume. The SI unit of density is kilograms per metre cubed. So now that we know what density is and we have our units, time to see how dense different materials are and then compare that to the Planck density, which is very dense indeed. At the end I’ll show you where the numbers come from. We’ll start off by looking at some very un dense things and work our way up. Video where I derive the Planck units mathematically https://youtu.be/VbTW7N_6PAQ Chapters 0:00 Introduction 0:15 What is Density? 1:30 The Density of Space 3:05 Air Density 4:05 Saturn 4:45 Water 5:23 The Planets 7:18 Metals 9:07 Stellar Objects 13:40 The Planck Density </video> <video> Measuring the Speed of Light Throughout History Description: Not only am I a lover of science, but I’m also very interested in the history of science and so I wanted to do an occasional series on some of our most important scientific breakthroughs and discoveries. For the first in this series I want to look at the speed of light, how we first measured it, and how we measure it today. Let's find out more. Before we start let us look at what the speed of light actually is. It is 299 million, 792 thousand 458 metres per second. That is 186 thousand 282 point 4 miles per second. That value has now been set and won’t change, it was actually set in 1983. The speed of light isn’t just the speed of light though, it’s the speed of causality. It is the universes ultimate speed limit. Objects and particles with mass are slowed down by that mass and so must travel slower than the speed of light. Massless things such as electromagnetic waves of which visible light is just one type are not slowed down by any mass and so are able to travel at this ultimate speed. Chapters 0:00 Introduction 2:00 Ancient Times 3:07 Beeckman and Galileo 4:45 Ole Roemer 6:52 James Bradley 8:15 Hippolyte Fizeau 9:50 Leon Foucault 10:50 Weber & Kohlrausch 11:50 James Clerk Maxwell 12:50 Albert Michelson 14:50 Cavity Resonance 16:15 Home Experiment 17:00 Interferometry Ole Roemer Image Jacob Coning, Public domain, via Wikimedia Commons Hasan Ibn al Haytham image artwork drawn by Adolph Boÿ, engraved by Jeremias Falck, Public domain, via Wikimedia Commons Christiaan Huygens Image Caspar Netscher, Public domain, via Wikimedia Commons Albert Michelson Image The original uploader was Bunzil at English Wikipedia., Public domain, via Wikimedia Commons </video> <video> The History of Our Solar System: How did the Sun and Planets form? Description: So far I’ve looked at the history of the universe right up to the point at which our solar system starts to form and in this video I’m going to look at how our solar system developed right up to the present day. I’m not going to cover the earth in this video, I’m going to leave that for a video all of it’s own, but in this video I’ll cover the rest of the planets and the sun, Let’s find out more. The formation of our solar system has for a long time been a topic of avid research, and there are many models to explain its formation, most of which have been modified with the discovery of extra solar planetary systems. There isn’t the time in this video to look at every model for the formation of every planet but I will look at some of the candidates. Chapters 0:00 Introduction 0:40 Formation of the Sun 4:00 How do Planets form? 4:40 Core Accretion 5:25 Disk Instability 5:55 Pebble Accretion 6:35 Gas Giant formation 11:20 Rocky Planet formation 14:20 Mercury 15:20 Venus 17:25 Mars 18:55 Jupiter 20:15 Saturn 21:10 Uranus 22:20 Neptune 22:35 Kuiper Belt & Pluto 22:55 Credits Credits Planet Textures & Materials Solar System Scope, CC BY 4.0 (https://creativecommons.org/licenses/by/4.0) https://www.solarsystemscope.com/textures/ Ganymede, Callisto and Io materials & Textures created by Björn Jónsson https://bjj.mmedia.is/data/planetary_maps.html </video> <video> History of the Universe: What happened in the first Second Description: I wanted to make a video looking at the history of the universe, but a lot had happened so I've decided to turn it into a video series. This first video will look at just the first second. The accepted version of events is called the big bang, but even here there are lots of things we don’t know and lots of potential models to explain what happened. Our current models fit the observational evidence and the mathematical models that we have constructed. Let’s start at the beginning at time = 0. Already we are getting into strange territory here. The big bang didn’t happen at a point in space and time. The big bang happened everywhere. When we think of explosions, we think of them happening in a particular place, and this is a problem with the way that we tend to imagine the start of the universe. The big bang was an expansion of space itself. 0:00 Introduction 0:20 The Big Bang 1:30 The Planck Epoch 3:05 The Hartle-Hawking Model 3:40 The Grand Unification Epoch 5:10 Inflation 5:45 The Horizon Problem 7:21 The Inflaton Field 8:50 The Electroweak Epoch 10:20 The Quark Epoch 11:05 The Higgs Field and Mass 12:20 The Hadron Epoch 13:30 Subscribe Please! 13:44 Our Universe is Strange </video> <video> Calculating the Planck Units Description: I’ve looked at a number of the Planck units, comparing them to other things, and it was lots of fun, but now I want to now look at where these units come from and how they came to be derived. Let’s find out more. This is going to be a very maths-ey video, and because I always wanted to make videos accessible to everyone I’m going to spend the first part of the video explaining some of the mathematical conventions that I will be using. Ok so let us think about why we have the need for the Planck units. Well let us think about time, the SI unit of time is the second, but humans came up with the concept of the second, it was historically measured as a fraction of a day on this planet, and even though we’ve now redefined it to a great degree of accuracy, it is still related to that ancient measurement. The same goes for all our measurements of length, temperature and mass. Wouldn’t it be great if we could find some way of defining these measurements that isn’t reliant on human made values. This would then transcend our human values. So can we define length, time, temperature and mass just in terms of universal constants. Chapters 0:00 Introduction 0:34 Idea 1 – Units 1:35 Idea 2 – Indices 2:16 Idea 3 – Fractions as Indices 2:38 Idea 4 – Negative Indices 3:48 Idea 5 – Multiplying Indices 4:22 Why do we need them? 5:12 Fundamental Constants 7:18 h bar the Reduced Planck Constant 9:04 G the Gravitational Constant 9:28 c the speed of Light 9:48 kB the Boltzmann Constants 11:04 The Planck Length 15:36 The Planck Mass 18:06 Planck Time 19:56 Planck Temperature </video> <video> Strange Matter: So Stable it's Contagious Description: Now in glorious 4K vision! Today we are going to look at a particularly strange form of matter, literally called strange matter, and it’s contagious. It’s so stable that all matter in the universe might want to be strange. Let’s find out more. First let’s think about matter. What we call normal matter, although we don’t even call it normal matter, we just call it matter, is made from atoms and as I’ve already mentioned in a number of videos, atoms are made from protons, neutrons and electrons and even the protons and neutrons are made from smaller particles called quarks. Neutrons are made from 1 up and 2 down quarks and protons are made from 2 up and 1 down quark. So all the matter that we can see and normally associate with the term matter is made up of just 2 types of quark and electrons. So what about other types of quark, well quarks are quite strange things. Firstly, quarks come in different flavours (I know, physicists are weird), and there are 6 flavours, they are up and down, and those are the ones we are familiar with, but there are others. There are also top and bottom quarks, and finally we have strange and charm quarks. There are also corresponding antiquarks for each of the 6 flavours. Chapters 0:00 Introduction 0:50 Quarks 1:35 Mesons & Baryons 3:45 Strange Matter 4:50 Neutron Stars 6:20 Strange Quarks 7:50 Neutron Star Collisions 8:30 Strangelets 8:45 Strange Matter Spreads 9:20 Does Strange Matter really exist? </video> <video> What Holds the Universe Together? The Fundamental Forces Description: The universe is a wondrous place, but what makes it all tick. What holds it all together and stops everything from just flying off into… well space. In this video I’m going to have a beginners guide look at the fundamental forces that hold the universe together. Let’s find out more. There are a number of fundamental forces, or interactions as they tend to be called, and I’m going to take each of them in turn and explain what they do. They are called fundamental because they can’t be resolved into other simpler interactions. For instance the force of friction, can be explained by using another force called electromagnetism, electromagnetism however, can’t be explained using any simpler force, and so electromagnetism is one of our fundamental interactions, but more about that later. The interactions that I’m going to look at today are electromagnetism, that I’ve already mentioned, the strong interaction, which is sometimes also called the strong force or the strong nuclear force. The weak interaction or the weak force or the weak nuclear force, and gravity, but gravity is a bit strange so I’ll leave that till the end. My Vacuum Decay video https://youtu.be/1zDzbXbt7Hc Ask a Physicist Anything by Joe McCullough https://youtu.be/3Q82mnaq6J4 Stable elements graph Table_isotopes.svg: Napy1kenobiderivative work: Sjlegg, CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0), via Wikimedia Commons Chapters 0:00 Introduction & Explanation of what will be covered 1:20 The Strong Interaction 4:10 Particles Involved 5:30 The Weak Interaction 8:45 Beta Minus Decay 11:20 Beta Plus Decay 12:55 Electromagnetism 13:45 Virtual Particles 14:45 Why do like charges repel? 15:50 Why do opposite charges attract 17:10 The Electroweak Force 18:10 Gravity 20:40 Gravity and acceleration </video>

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Description

What is Learning Curve all about?

The Universe is an amazing place, and the goal of this channel is to uncover some of its secrets.

I have been a science teacher for over 20 years, and I'm constantly amazed by the world and the universe around me. Having an inquisitive mind has set me on a mission to explore as many of the fantastic things I find as possible, and explain them to you.

So if you have an inquisitive mind too, then make sure to subscribe and check back to find out what I've learned each week. As I always say, curiousness makes us human.

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