Scientists have recently discovered nanodiamonds in the flames of ordinary candles. They are produced at a rate of about 1.5 million per second. Unfortunately they are also burned up at this rate and released into the atmosphere as carbon dioxide. Still this finding may prove useful in the ongoing search for economical ways to produce diamonds.

Light is so common that we rarely think about what it really is. But just over two hundred years ago, a groundbreaking experiment answered the question that had occupied physicists for centuries. Is light made up of waves or particles?

The experiment was conducted by Thomas Young and is known as Young's Double Slit Experiment. This famous experiment is actually a simplification of a series of experiments on light conducted by Young. In a completely darkened room, Young allowed a thin beam of sunlight to pass through an aperture on his window and onto two narrow, closely spaced openings (the double slit). This sunlight then cast a shadow onto the wall behind the apparatus. Young found that the light diffracted as it passed through the slits, and then interfered with itself, created a series of light and dark spots. Since the sunlight consists of all colours of the rainbow, these colours were also visible in the projected spots. Young concluded that light consist of waves and not particles since only waves were known to diffract and interfere in exactly the manner that light did in his experiment.

The way I have always seen this experiment performed is with a laser and a manufactured double slit but since the experiment was conducted in 1801 I have always thought that it should be possible to recreate the experiment using sunlight and household materials. That is basically what I did here. I will show the interference pattern I observed with my homemade double slit on 2Veritasium but I chose to use a manufactured double slit here to ensure that the pattern was impressive for observers at the beach.

Special thanks to Henry, Brady, and Rupert for their cameos, Glen for filming and Josh for helping create the apparatus. Thanks also to the Royal Society for allowing us to view the original manuscript of Young's lecture and the University of Sydney for lending the double slits.

Music by Kevin Mcleod (incompetech.com) Danse Macabre, Scissors

Cell biology gives clues to why we age and lobsters don't.
I made another video! The future of energy: http://bit.ly/1MAiJKm
Check out Breakthrough, Sundays at 9/8c on Nat Geo with GE #ad

Animations are from Emmy-winning film 'Immortal', reproduced here courtesy of December Media and Genepool Productions (previously Pemberton Films)

Check out Immortal here: http://bit.ly/VeImmortal

Find out more about telomeres and telomerase here: http://bit.ly/WakeTelomeres

Special thanks to Dr. Fiona Ginty, Principal Scientist in the Life Sciences and Molecular Diagnostics Group at GE. Her research focuses on imaging different proteins within the cell. It's both a very powerful technique and it's beautiful.

Filmed by Raquel Nuno and Vasilios Sfinarolakis
Aging makeup by Heather Grippaldi: http://bit.ly/1Xebikh
Music by Kevin MacLeod, www.incompetech.com "Past the Edge" and "Lightless Dawn"

Compliant mechanisms have lots of advantages over traditional devices. SimpliSafe is awesome security. It's really effective, easy to use, and the price is great. Check out SimpliSafe here: https://simplisafe.com/veritasium

I visited the Compliant Mechanisms Research group at Brigham Young University and spoke to Professor Larry Howell:
https://www.compliantmechanisms.byu.edu

At the above link, you can download 3D-print files to make some of the objects in the video, plus learn more about compliant mechanisms.

What I learned about compliant mechanisms I summarize in the 8 P's of compliant mechanisms:

1. Part count (reduced by having flexible parts instead of springs, hinges)
2. Productions processes (many, new, different enabled by compliant designs)
3. Price (reduced by fewer parts and different production processes)
4. Precise Motion (no backlash, less wear, friction)
5. Performance (no outgassing, doesn't require lubricant)
6. Proportions (reduced through different production processes)
7. Portability (lightweight due to simpler, reduced part count designs)
8. Predictability (devices are reliable over a long period of time)

Special thanks to Patreon supporters:
Donal Botkin, James M Nicholson, Michael Krugman, Nathan Hansen, Ron Neal, Stan Presolski, Terrance Shepherd

Animation by Alan Chamberlain

The atmosphere applies a pressure of about 100 000 N to every square metre on Earth's surface. We take this pressure for granted because we have the same amount of pressure pushing out. But what happens when the pressure of the atmosphere is applied to an object with no outward pressure? It implodes. In spectacular fashion.

Common pitfalls of New Year's resolutions and how I plan to avoid them. Thanks Audible! Start listening with a 30-day trial and your first audiobook plus two Audible Originals free when you go to https://audible.com/veritasium or text veritasium to 500500.

Thanks to Simone Giertz for sending me and Every Day Calendar!
Get notified when they're available to order here: http://www.simonegiertz.com/every-day-calendar

Special thanks to Patreon Supporters:
Alfred Wallace, Arjun Chakroborty, Chuck Lauer Vose, Dale Horne, Jasper Xin, Joar Wandborg, Kevin Beavers, Leah Howard, Lyvann Ferrusca, Michael Krugman, Noel Braganza, Ron Neal, Tige Thorman

In the mid 1800's scientists successfully passed an electric current through a vacuum in a glass tube. They saw a glow from the tube that seemed to emanate from the negatively charged plate called the cathode. Since scientists didn't know what the glow was they called it a cathode ray. There was debate over whether the cathode ray was a wave phenomenon like light or a stream of negatively charged particles. JJ Thomson effectively resolved the debate in 1897 by performing a clever experiment that determined the charge to mass ratio of the particles making up the cathode ray. He also showed that this same particle was in all different cathode materials so it must be a constituent common to all atoms. This changed our understanding of the atom from the previous billiard ball model to Thomson's plum pudding model of the atom.

The Event Horizon Telescope Collaboration observed the supermassive black hole at the center of M87, finding the dark central shadow in accordance with General Relativity, further demonstrating the power of this 100 year-old theory.

To understand more about why the shadows look the way they do, check out: https://www.youtube.com/watch?v=zUyH3XhpLTo

I will continue updating this description with more links.

Event Horizon Telescope collaboration: https://ve42.co/EHT

Animations and simulations with English text:
L. R. Weih & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/jvftAadCFRI

Video of observation of M87 courtesy of:
C. M. Fromm, Y. Mizuno & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/meOKmzhTcIY

Video of observation of SgrA* courtesy of
C. M. Fromm, Y. Mizuno & L. Rezzolla (Goethe University Frankfurt)
Z. Younsi (University College London)
https://youtu.be/VnsZj9RvhFU

Video of telescopes in the array 2017:
C. M. Fromm & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/Ame7fzBuFnk

Animations and simulations (no text):
L. R. Weih & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/XmvpKFSvB7A

Special thanks to Patreon supporters:
Donal Botkin, Michael Krugman, Ron Neal, Stan Presolski, Terrance Shepherd, Penward Rhyme

Scale animation by Maria Raykova

A forest is like a meadow on useless stilts.
Most amazing thing about trees: http://bit.ly/TFilQ8
Meetup in Stockholm Sunday, Apr 6 Cafe String

We often imagine that unregulated competition produces optimal outcomes, behaviours, efficiencies, but trees and baggage carousels are two examples where the stable solution is worse for everyone than another strategy. This I find surprising and interesting - that evolution doesn't come to the best solution, it comes to the most stable one.

The Forest of Friendship was a concept I first came across in Richard Dawkin's book "The Greatest Show on Earth." One point I'd like to clarify is that being taller comes with a cost - having a longer trunk requires costly expenditure of energy. However, in a forest of uniformly short trees, being a little taller conveys an advantage. That is until all the other trees catch up, at which time the extra height no longer provides a benefit. So over time as the whole forest rises up the conditions are getting worse for each tree, but they are powerless to stop the evolutionary arms race.

Huge thank you to Brady Haran for filming (and summarizing the main points at the end of the film). He is the amazing creator of:
Numberphile: http://youtube.com/numberphile
Sixty Symbols http://youtube.com/sixtysymbols
Periodic Videos http://youtube.com/periodicvideos
And many more...

When air is compressed very quickly, it can reach high temperatures. In this demonstration we show how cotton wool can reach the point of auto-ignition by quick compression of air in the fire syringe.

This is the first Veritasium science video. It addresses one of the most fundamental concepts in science: the idea that all things are made of atoms, tiny particles that are in perpetual motion. They attract each other when a little distance apart and repel when squeezed together.

The truth, with photons.
I hope I've articulated everything clearly in this video. If not, I'll clarify in comments. Thanks to everyone who appears in this video and thanks to everyone who watches this video!

Veritasium is of course a combination of the latin 'veritas' meaning truth, and the common element ending 'ium'. I guess this is my version of the 'draw my life' craze that rolled through YouTube many years ago. Except I wanted to tell my story with the actual moments, the photons, the stored magnetic states. There's something about that which is so important to me (because I think the alternative involves fooling yourself) which is why I'm so fascinated by film and video.

One of my inspirations for the name Veritasium came from the end of the poem Ode on a Grecian Urn by John Keats, in which he writes:
"Beauty is truth, truth beauty,—that is all
Ye know on earth, and all ye need to know."

Special thanks to Patreon supporters:
Tony Fadell, Donal Botkin, Michael Krugman, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen, Yildiz Kabaran,
Terrance Snow, Stan Presolski

Music from http://epidemicsound.com
Magnified X1 - Gunnar Johnsen
Fluorescent Lights - Martin Gauffin
Dissolving Patterns - Ebb & Flod
Luna - Ebb & Flod

Additional music by Kevin MacLeod: http://incompetech.com
Sneaky Snitch

When evolution favours a stable ratio of traits rather than one dominant trait.
Check out Audible: http://bit.ly/AudibleVe
Animation by The Lyosacks: https://www.youtube.com/TheLyosacks

Hosting Neil Degrasse Tyson, info and tickets: http://bit.ly/NDTandVe
Aug. 22 in Sydney
Aug. 23 in Canberra

Special thanks to Richard Dawkins

Filmed at Academia Film Olomouc with help from Martyn Marek

Music by Kevin MacLeod www.incompetech.com 'Marty Gots a Plan' 'Sing Along with Jim'

The logistic map connects fluid convection, neuron firing, the Mandelbrot set and so much more. Fasthosts Techie Test competition is now closed! Learn more about Fasthosts here: https://www.fasthosts.co.uk/veritasium Code for interactives is available below...

Animations, coding, interactives in this video by Jonny Hyman ?
Try the code yourself: https://github.com/jonnyhyman/Chaos

References:
James Gleick, Chaos
Steven Strogatz, Nonlinear Dynamics and Chaos

May, R. Simple mathematical models with very complicated dynamics. Nature 261, 459–467 (1976). https://doi.org/10.1038/261459a0

Robert Shaw, The Dripping Faucet as a Model Chaotic System
https://archive.org/details/Sh....awRobertDrippingFauc

Crevier DW, Meister M. Synchronous period-doubling in flicker vision of salamander and man.
J Neurophysiol. 1998 Apr;79(4):1869-78.

Bing Jia, Huaguang Gu, Li Li, Xiaoyan Zhao. Dynamics of period-doubling bifurcation to chaos in the spontaneous neural firing patterns Cogn Neurodyn (2012) 6:89–106 DOI 10.1007/s11571-011-9184-7

A Garfinkel, ML Spano, WL Ditto, JN Weiss. Controlling cardiac chaos
Science 28 Aug 1992: Vol. 257, Issue 5074, pp. 1230-1235 DOI: 10.1126/science.1519060

R. M. May, D. M. G. Wishart, J. Bray and R. L. Smith Chaos and the Dynamics of Biological Populations
Source: Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, Vol. 413, No. 1844, Dynamical Chaos (Sep. 8, 1987), pp. 27-44

Chialvo, D., Gilmour Jr, R. & Jalife, J. Low dimensional chaos in cardiac tissue. Nature 343, 653–657 (1990). https://doi.org/10.1038/343653a0

Xujun Ye, Kenshi Sakai. A new modified resource budget model for nonlinear dynamics in citrus production. Chaos, Solitons and Fractals 87 (2016) 51–60

Libchaber, A. & Laroche, C. & Fauve, Stephan. (1982). Period doubling cascade in mercury, a quantitative measurement. http://dx.doi.org/10.1051/jphy....slet:019820043070211 43. 10.1051/jphyslet:01982004307021100.

Special thanks to Patreon Supporters:
Alfred Wallace, Arjun Chakroborty, Bryan Baker, DALE HORNE, Donal Botkin, halyoav, James Knight, Jasper Xin, Joar Wandborg, Lee Redden, Lyvann Ferrusca, Michael Krugman, Pindex, Ron Neal, Sam Lutfi, Tige Thorman, Vincent

Special thanks to:
Henry Reich for feedback on earlier versions of this video
Raquel Nuno for enduring many earlier iterations (including parts she filmed that were replaced)
Dianna Cowern for title suggestions and saying earlier versions weren't good
Heather Zinn Brooks for feedback on an earlier version.


Music from:
https://epidemicsound.com "What We Discovered" "A Sound Foundation 1" "Seaweed" "Colored Spirals 4"

https://ve42.co/Artlist "Busy World" "Children of Mystery"

Panem finds power in the radiance of the sun, and the water which rains down upon us! District 5’s Chief Energy Researcher Derek Muller takes CapitolTV on a tour of our nation's cutting edge renewable technologies, and demonstrates one of the largest ‘Kelvin’s Thunderstorm’ experiments ever built to date… all for a brighter and more efficient Panem.

Sanctioned by the Capitol Ministry of Information, DISTRICT VOICES was made with friends from Google - http://artcopycode.com/campaign/lionsgate

For more of Panem’s finest programming, and to register for updates, visit http://CapitolTV.pn
#CapitolTV - #DistrictVoices

The Hunger Games: Mockingjay Part 1 – In theaters November 21
http://TheHungerGamesExplorer.com
#Mockingjay

Physics of contraptions meant to go faster than light.
Audible: http://bit.ly/AudibleVe
My video about the problem with Facebook: http://bit.ly/PwFB

Special thanks to MinutePhysics for visual effects and Prof. Geraint Lewis for revisions to earlier drafts of this video.

The sun has been producing light for about five billion years but where does all its energy come from? The most common idea is that the sun is burning gas - like a giant fireball in the sky. If this were true, the sun would have gone out long ago. So how is the sun actually fuelling itself? It is converting its own mass into energy. By combining protons (the nucleus of hydrogen) into helium, it squeezes some mass into energy - 4.3 billion kg per second. It is Einstein's famous E=mc^2 which gives us the quantitative relationship between mass and energy, where c is the speed of light.

I've created an educational product to help people learn chemistry!
You can buy it here: http://www.snatoms.com

Space junk is a real problem. NASA now tracks around 20,000 pieces of debris orbiting Earth, most of them larger than 10cm across. Since the average speed of a collision between orbiting objects is 10 km/s these pieces of trash can cause a lot of damage despite their small size.

Scientists in Switzerland have a plan to clean up space junk - it involves creating a 'Janitor Satellite' that will seek out pieces of space junk to drag back into the atmosphere causing them to burn up.

This video was created for the Aussie science show Catalyst on the ABC: http://www.abc.net.au/catalyst

This is what the world would look like if you could see invisible air currents, temperature gradients, and differences in pressure or composition of the air.
Support Veritasium on Patreon: http://ve42.co/patreon

Special thanks to Patreon Supporters:
Tony Fadell, Donal Botkin, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen

I first saw a Schlieren imaging setup around ten years ago in Melbourne. I was immediately fascinated by the way I could see the warm air coming off my hand. I hadn't expected the currents to be moving that fast or to be so visible. This was a tricky setup to get right because alignment is very important and here I'm just working with what I had lying around the house mostly (plus the mirror). For the best Schlieren photography, making sure the mirror is stable is essential. I want to improve my setup so the mirror doesn't wobble back and forth too much creating the pulsing light and dark sections of this video.

The relationship between index of refraction of air and temperature, pressure, humidity and wavelength is complicated. This website will calculate it for you: http://emtoolbox.nist.gov/Wavelength/Ciddor.asp

Slow motion by Hollywood Special Ops: http://www.hollywoodspecialops.com

Sound Effects by A Shell in the Pit: http://www.ashellinthepit.com

Filmed by Raquel Nuno
Special thanks to Blake Nichols for assistance