Longyearbyen on Svalbard is the northernmost settlement with over 1000 residents
My trip to Norway was funded by Screen Australia, Film Victoria and Genepool Productions as part of a new project. More information soon.

More info on Svalbard: http://wke.lt/w/s/yiYNC

Music licensed from www.cuesongs.com "After Catalunya"
Spotify page: https://play.spotify.com/artis....t/2JnQ2AxkaRjlGCNmfk
iTunes: https://itunes.apple.com/gb/ar....tist/emphemetry/id41

Captions:
Come take a walk with me around Longyearbyen, the largest town on the Norwegian islands of Svalbard.

Parts of it look familiar, but make no mistake, this place is different.

At 78 degrees North, it lies just 800 miles or 1300 kilometres from the North Pole. And with over 2,000 permanent inhabitants it is the Northernmost real town on Earth.

There are only 50km of road, including the small streets between houses, so people get around the island mainly on snowmobile.

In fact there are more registered snowmobiles than residents.

Anyone leaving town is required to travel with a gun and someone who knows how to use it because the islands are also home to polar bears.

The average daytime high is below freezing for all but four months of the year, and from the end of October to mid-February the sun doesn’t rise at all. This is the long polar night.

Living here is tough. This past December an avalanche in town destroyed 10 homes, which used to be here, killing two people.

So how did this cold, remote, ice-covered archipelago come to be inhabited?

The hills around town are rich in coal deposits that have been mined for over 100 years.

The coal was transported to the port via a series of aerial tramways some of which remain today, though they are no longer operational.

Coal is a reminder that Svalbard was not always an Arctic ice world. 360 million years ago it was actually in the tropics North of the equator. A swampy area, it was covered with the precursors to modern ferns, which were much larger than they are today, reaching 10-30 metres in height.

This vegetation was then covered in mud and sand and submerged under the sea. Over time it turned into the coal deposits that in the 20th century brought miners from Norway, Russia, and the US.

Most of the coal mines have now closed and the economy is gradually shifting towards tourism, education and research.

Tourists take trips on snowmobiles and dog sleds.

There is a university centre in Svalbard, which offers semester courses in biology, physics and geology.

And up on the side of a mountain is the Svalbard Global seed vault… but that’s a story for another time.

The locals tell me that interest in the region from different nations is increasing.

As the globe warms and Arctic ice shrinks, trade routes are opening up across the North. And Svalbard is strategically placed between North America, Asia and Europe.

One day in the future Svalbard may no longer be as cold or remote as it once was.

But for now it is a reminder of how through our ingenuity people can live in the most inhospitable of places.

Shot with a DJI Phantom 4 drone

A launch mishap led to the best experimental confirmation of gravitational redshift. Get a free audiobook with a 30-day trial of Audible: http://audible.com/VERITASIUM or text VERITASIUM to 500500

Huge thanks to
Dr. Pacome Delva: https://ve42.co/pacome
Dr. Sven Herrmann: https://ve42.co/sven
Gravitational Redshift Test Using Eccentric Galileo Satellites: https://ve42.co/GRtest

Disclaimer: It is arguable what is THE best test of general relativity because there are different ways to test the theory. This is the best confirmation of gravitational redshift, which is one of the three original tests proposed by Einstein.

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

Animations and editing by Alan Chamberlain

Music from http://epidemicsound.com "Subtle Substitutes 2" "A sound Foundation 1" "Cell Research 1" "Particle Attraction 1"

The world's roundest object helps solve the longest running problem in measurement -- how to define the kilogram.
Support Veritasium on Patreon: http://bit.ly/VePatreon

A kilogram isn't what it used to be. Literally. The original name for it was the 'grave', proposed in 1793 but it fell victim to the French Revolution like its creator, Lavoisier. So begins the tale of the most unusual SI unit. The kilogram is the only base unit with a prefix in its name, and the only one still defined by a physical artifact, the international prototype kilogram or IPK.

But the problem with this definition has long been apparent. The IPK doesn't seem to maintain its mass compared to 40 similar cylinders minted at the same time. The goal is therefore to eliminate the kilogram's dependence on a physical object. Two main approaches are being considered to achieve this end: the Avogadro Project and the Watt Balance.

The Avogadro project aims to redefine Avogadro's constant (currently defined by the kilogram -- the number of atoms in 12 g of carbon-12) and reverse the relationship so that the kilogram is precisely specified by Avogadro's constant. This method required creating the most perfect sphere on Earth. It is made out of a single crystal of silicon 28 atoms. By carefully measuring the diameter, the volume can be precisely specified. Since the atom spacing of silicon is well known, the number of atoms in a sphere can be accurately calculated. This allows for a very precise determination of Avogadro's constant.

Special thanks to Katie Green, Dr. David Farrant, the CSIRO, and the National Measurment Institute for their help. Thanks also to Nessy Hill for filming and reviewing earlier drafts of this video.

There is debate as to whether this is truly the roundest object ever created. The Gravity Probe-B rotors are also spherical with very low tolerances such that they may in fact be rounder.

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

The Earth spins on its axis, completing a full revolution every day. By why does it do this? One of the most common misconceptions in physics is the belief that constant motion requires a constant force. So many people believe there must be some force in the Earth (e.g. gravity, centrifugal force) that keeps it spinning. In truth, no force is required because a fundamental property of mass is that it maintains its state of motion in the absence of external forces. This property is called inertia.

How do you measure big forces accurately? By calibrating your force transducer on the world's biggest weight - 1,000,000 pounds of force. This machine ensures planes don't break apart, jets provide required thrust, and rockets make it to their destination.

Thanks to the people at NIST for showing me around: Rick Seifarth and Ben Stein. Animations here are by Sean Kelley and additional footage by Jennifer Lauren Lee.

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

Support Veritasium on Patreon: http://ve42.co/patreon

Before visiting NIST in Washington DC I had no idea machines like this existed. Surely there's an accurate way to measure forces without creating such a huge known force?! Nope. This appears to be the best way, with a stack of 20 x 50,000 lb masses creating a maximum force of 4.45 MN or 1,000,000 pounds of force. I also wouldn't have thought about all the corrections that need applying - for example buoyancy subtracts about 125 pounds from the weight of the stack. Plus the local gravitational field strength must be taken into account. And, the gravitational field varies below grade. All of this must be taken into account in order to limit uncertainty to just five parts per million (.0005%)

Music from The Epidemic Sound http://epidemicsound.com "Serene Story 2"

Will artificial intelligence weapons cause World War III? https://www.youtube.com/watch?v=qiJTq11kqdw
This animated clip is from my friends at http://ve42.co/pindex2
New series! http://vrv.co/paradigms

I'm not sure how alarmed to be about artificial intelligence. Personally I think it's really hard to predict when we'll create a machine that essentially has consciousness. That's because we don't know what consciousness is, how it works, what's required to create it etc. So It might be technologically around the corner or a hundred years away.

What I do think is more predictable is the development of autonomous weapons that use AI to be the most effective killing machines of all time. That is scary. As outline by people like Musk and Hawking, this threat is clear and present so we should address it. I would like to see us agree as a species not to develop these sorts of weapons because if any one state does develop them, they would be very hard to stop.

New research shows chameleons actively tune nano-crystals to change their color.
For a 10-day free trial, check out http://lynda.com/veritasium
Chameleon research in Nature Communications: http://bit.ly/1FacHO2
"Photonic Crystals Cause Active Colour Change in Chameleons"

This research was carried out by Jérémie Teyssier, Suzanne V. Saenko, Dirk van der Marel & Michel C. Milinkovitch at the University of Geneva Department of Quantum Matter Physics and the Laboratory of Artificial and Natural Evolution (LANE)

Original videos of chameleons are here:
https://www.youtube.com/watch?v=YIRiCwHlUd8
https://www.youtube.com/watch?v=XdQvtP8EKrM
https://www.youtube.com/watch?v=YSH7EmXFMac
https://www.youtube.com/watch?v=egwueh6wj1E

Additional details available at: http://www.lanevol.org/LANE/ch....ameleon_colour_chang
For correspondence: Michel C. Milinkovitch, Laboratory of Artificial & Natural Evolution (LANE), Dept. of Genetics & Evolution, University of Geneva, Switzerland.

The melanin spreading out video is courtesy of Richard Wheeler:
https://www.youtube.com/watch?v=hL0USeWjTHQ
http://www.richardwheeler.net

Special thanks to:
Harry, Jo, Daniella and Raquel for helping me produce and film this video - it looks great thanks to you!

Some months a go I filmed a slinky falling in slow motion. Now I have interviewed the public about what they expect to happen for ABC TV's Catalyst program and this is the result.

Can you figure out the rule?
Did you see the exponents pattern? http://youtu.be/AVB8vRC6HIY
Why do you make people look stupid? http://bit.ly/12Fmlpl

How do you investigate hypotheses? Do you seek to confirm your theory - looking for white swans? Or do you try to find black swans? I was startled at how hard it was for people to investigate number sets that didn't follow their hypotheses, even when their method wasn't getting them anywhere.

In the video I say "when people came to Australia..." by which I meant, "when Europeans who believed all swans were white came to Australia..." I did not mean any offence to Indigenous Australians who were already in Australia at that time. Please accept my apologies for the poor phrasing if you were offended by it.

This video was inspired by The Black Swan by Nassim Taleb and filmed by my mum. Thanks mum!

Partly my motivation came from responses to my Facebook videos - social media marketers saying 'Facebook ads have worked for me so there can't be fake likes.' Just because you have only seen white swans, doesn't mean there are no black ones. And in fact marketers are only looking for white swans. They think it was invalid of me to make the fake Virtual Cat page: 'well of course if it's a low quality page you're going to get low quality likes.' But my point is this is black swan bait, something they would never make because their theory is confident in the exclusive existence of white swans.

Spinning magnets near copper sheets create levitation!
Try Audible free for 30 days: http://bit.ly/AudibleVe
Special thanks to Hyperloop One for showing me around.

Thanks to Patreon supporters:
Nathan Hansen, Donal Botkin, Tony Fadell, Saeed Alghamdi, Zach Mueller, Ron Neal, Perry cl, Bryan Baker
Support Veritasium on Patreon: http://bit.ly/VePatreon

Filmed by Raquel Nuno, Edited by Trevor Carlee

Obviously this "quadcopter" is a demonstration device, showing how moving magnets over a conducting surface can generate levitation. It has not been optimized to minimize losses or be an efficient mode of transport. I still think it's pretty cool. I'm used to seeing light things levitated by induced currents but not a 100+ lb machine.

For more on Hyperloop One: https://hyperloop-one.com/

Scientists have to work with some very large and some very small numbers. To represent these numbers more easily, they use scientific notation. Scientific notation relies on powers of 10. This video gives examples of how to represent a large and small number and explains powers of ten.

Key aspects of pyramid construction from quarry to completion.
Check out Audible: http://bit.ly/AudibleVe
Live show in Alabama: http://bit.ly/VeRAOI

The most common misconception about the pyramids is that they were built by slaves. Recent archeological evidence suggests they were instead constructed by paid workers. Some may have performed this work as a form of tax payment for several months of the year. Skilled engineers would have planned and orchestrated the building. An estimated 10,000-20,000 people would have been working on a pyramid at any one point in time. They were well fed and provided with shelter near the pyramids. Plus their burial sites close by indicate they were respected and were not slaves.

Much of the limestone was quarried from the Giza plateau itself, meaning the stones did not need to be transported far. The granite casing of Menkaure's pyramid, on the other hand, was transported from Aswan, around 600 miles, or 1000 km up the Nile.

Editing assistance by Dustin Chow

Music by Kevin MacLeod, Incompetech.com "Desert City" and "Ibn Al-Noor"

What is the longest drinking straw that you can actually drink out of? Well in this video, we put the theory to the test. We started off with a one metre long straw made out of drinking straws taped together. We moved on to two pieces of plastic tubing, each 6 metres in length with different diameters. Then we tried a 10.5 metre tube over a cliff's edge. The maximum we achieved was about 7 metres though theoretically up to 10.3 metres is possible if a perfect vacuum is created.

Aerogels are the world's lightest (least dense) solids. They are also excellent thermal insulators and have been used in numerous Mars missions and the Stardust comet particle-return mission. The focus of this video is silica aerogels, though graphene aerogels are now technically the lightest.

At one point Dr. Steven Jones literally held the Guinness World Record for making the lightest aerogel and therefore lightest solid. If you're interested in learning more about aerogels, let me know in the comments as there is a potential trilogy in the works...

Huge thanks to Dr. Stephen Steiner and the crew at Aerogel Technologies. To find out more or buy your own aerogel sample, check out: http://www.aerogeltechnologies.com/

Thanks to Dr. Steven Jones and Dr. Mihail Petkov at NASA's Jet Propulsion Laboratory

And thanks to FLIR for loaning us the awesome high definition thermal camera. The footage is amazing! https://www.flir.com

Special thanks to Patreon supporters:
Donal Botkin, Michael Krugman, Ron Neal, Stan Presolski, Terrance Shepherd, Penward Rhyme and everyone who provided feedback on an early draft of this video.

Filming by Raquel Nuno
Animations by Maria Raykova
Drawings by Mariel Solsberg

Music From http://epidemicsound.com "Seaweed" "Swagger Stagger"

Remarkably little is known about great white sharks, but they are similar to humans in a lot of ways - they give birth to live young, maintain a higher body temperature than their surroundings and they are apex predators. There are also many misconceptions about these sharks: people think they don't get cancer and that they reside mainly in shallow waters near beaches. In this video I summarize some of the most interesting things I learned about sharks on my cage diving adventure.

Special thanks to Rodney Fox Shark Expeditions for making this trip possible: http://bit.ly/rodneyfox

Thanks also to Tourism South Australia for facilitating the trip: http://bit.ly/1aq9MgV

Chris Cassella or C² as he is known after this trip was a shark spotter extraordinaire. He also took some of the best shark footage in this video. It was his idea to go on this expedition, which was definitely a once in a lifetime experience, so I am in his debt. Chris, I look forward to going on more great adventures with you. Check out Chris's facebook page ScienceAlert http://on.fb.me/18nhyLp

The strange thing about high jump is that the technique changed dramatically after 1968, when Dick Fosbury used his trademark flop to win the gold medal at the Olympics in Mexico City.
Previously the scissors and straddle had been the most common jumping technique, but after the introduction of safer landing matts, the new unorthodox Fosbury Flop became the jump of choice. There are good physical reasons for this - the style allows the jumper to pass over the bar while his or her centre of mass actually passes below the bar.

Huge thanks to Elly (Appchat http://bit.ly/NxAMlX ) for filming, editing, and music!

numberphile http://bit.ly/numberphile
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appchat http://bit.ly/NxAMlX
erikaanear http://bit.ly/MdyUzQ
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The US signed the metre convention and bases all customary units on SI standards. As an aside, the Utah constitution from 1895 required the metric system to be taught in schools. This requirement was repealed in 1987. ¯\_(ツ)_/¯

Huge thanks to NIST, Ben Stein and Patrick Abbott.
https://www.nist.gov/
https://www.nist.gov/pml/weights-and-measures/si-units-mass

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

Back in 1875 The US signed the Metre Convention, which basically committed the country to use the metric system. In return, French scientists sent two platinum-iridium cylinders that weigh 1kg to the US in 1889 (known by their designations K4 and K20 from a set of 40 identical objects that were produced and sent around the world). So even though everything you see and buy in the US is usually reported in pounds, all weights are traceable back to the K20 kilogram (by applying a conversion factor to get to pounds).

When I was in DC a few weeks ago, I visited the National Institute of Standards and Technology (NIST) and got up close with K20, which is still kept there and used to calibrate all mass standards in this country. I thought it was pretty cool.

Edited by Bill Connor

Most people recognize that atoms are the fundamental building blocks of all matter around us. An atom itself is composed of protons, neutrons and electrons. The simplest atom is the hydrogen atom because it consists of only one proton and one electron. If a neutron is added to the nucleus, the atom is still hydrogen, just a more massive version. Atoms of the same element (i.e. those with the same number of protons) but different numbers of neutrons are called isotopes.

Five cool physics tricks, but how do they work?
Explanations: http://youtu.be/jIMihpDmBpY
Check out Audible.com: http://bit.ly/AudibleVe
Leave your ideas in the comments below or subscribe for the answers next week.

Chris Hadfield in AUS: http://sciencealert.com.au/spaceoddity/
All tickets now sold out.

The Cane Balance:
Slide your fingers in from the ends of a horizontal cane to find its centre of mass.

Shot and Edited by Pierce Cook at the YouTube Space LA.

Music by Amarante: http://bit.ly/VeAmarante

Which weight hits the ground first - the free weight or the weight attached to the chain?