Silicone oil droplets provide a physical realization of pilot wave theories.
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Filmed by Raquel Nuno

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Nathan Hansen, Bryan Baker, Donal Botkin, Tony Fadell, Saeed Alghamdi

Thanks to Google Making and Science for helping me pursue my #sciencegoals. If you want to try this experiment, instructions are here: link.springer.com/article/10.1007/s12650-016-0383-5

The standard theory of quantum mechanics leaves a bit to be desired. As Richard Feynman put it, "I think I can safely say that no one understands quantum mechanics." This is because observations of experiments have led us to a theory that contradicts common sense. The wave function contains all the information that is knowable about a particle, yet it can only be used to calculate probabilities of where a particle will likely turn up. It can't give us an actual account of where the particle went or where it will be at some later time.

Some have suggested that this theory is incomplete. Maybe something is going on beneath the radar of standard quantum theory and somehow producing the appearance of randomness and uncertainty without actually being random or uncertain. Theories of this sort are called hidden variable theories because they propose entities that aren't observable. One such theory is pilot wave theory, first proposed by de Broglie, but later developed by Bohm. The idea here is that a particle oscillates, creating a wave. It then interacts with the wave and this complex interaction determines its motion.

Experiments using silicone oil droplets on a vibrating bath provide a remarkable physical realization of pilot wave theories. They give us a physical picture of what the quantum world might look like if this is what's going on - and this theory is still deterministic. The particle is never in two places at once and there is no randomness.

Edited by Robert Dahlem

Sound design by A Shell in the Pit

Boredom makes you more creative, altruistic, introspective, and helps with autobiographical planning.
This video was sponsored by LastPass: http://bit.ly/2wAsdUu

I feel like this video might come across as condescending but the person I'm really talking to is myself. Despite the fact that I know how useful it can be to be bored, I still find myself trying to fill every last moment with stimulus. Boredom is unpleasant - the open, unstructured thinking that can take place can also feel pointless. But now I'm made this video to remind myself how important boredom is so hopefully I'll make more time to be bored.

More resources:

The boredom leads people to shock themselves study:
Just Think: The challenges of the disengaged mind
https://wjh-www.harvard.edu/~d....tg/WILSON%20ET%20AL%

Boredom leads people to consider their future and set goals study:
Back to the future: Autobiographical planning and the functionality of mind-wandering
https://www.sciencedirect.com/....science/article/pii/

On boredom and altruism:
https://pdfs.semanticscholar.o....rg/ca72/0f959d3c9c31

Does boredom make us more creative?
https://www.tandfonline.com/do....i/abs/10.1080/104004

Amazing filming by Raquel Nuno

Music from http://epidemicsound.com "I Think I Was There" "Critical Thinking 2" "Wide Open" "Seaweed" "A Sound Foundation 1"

Music also by Kevin MacLeod http://incompetech.com "Fig Leaf Rag"

How does a transistor work? Our lives depend on this device.
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When I mentioned to people that I was doing a video on transistors, they would say "as in a transistor radio?" Yes! That's exactly what I mean, but it goes so much deeper than that. After the transistor was invented in 1947 one of the first available consumer technologies it was applied to was radios, so they could be made portable and higher quality. Hence the line in 'Brown-eyed Girl' - "going down to the old mine with a transistor radio."

But more important to our lives today, the transistor made possible the microcomputer revolution, and hence the Internet, and also TVs, mobile phones, fancy washing machines, dishwashers, calculators, satellites, projectors etc. etc. A transistor is based on semiconductor material, usually silicon, which is 'doped' with impurities to carefully change its electrical properties. These n and p-type semiconductors are then put together in different configurations to achieve a desired electrical result. And in the case of the transistor, this is to make a tiny electrical switch. These switches are then connected together to perform computations, store information, and basically make everything electrical work intelligently.

Special thanks to PhD Comics for awesome animations: http://bit.ly/16ZXcVY

And thanks to Henry Reich and Vanessa Hill for reviews of earlier drafts of this video.

Music: Kevin MacLeod (incompetech.com) Decisions

How lift actually works: http://www.youtube.com/watch?v=aFO4PBolwFg
More with Canadian Olympian Hunter Lowden: http://www.youtube.com/watch?v=6YVOPUkbu6g

How does a sailboat work? The standard idea is that the wind pushes the sails from behind, causing the boat to move forward. Although this technique is used at times, it is not the most efficient way to sail a boat (and it means the boat can never go faster than the wind). Lift is the key mechanism driving a boat forwards. As air flows over the sails, it moves faster over the outer side, creating lower pressure than on the inner side. This produces a force which is mostly to the side and a bit forwards. Lift on the centerboard pushes to the opposite side, cancelling the sideways force and adding a forward component of force to the boat.

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Stained glass is thicker at the bottom - so is it a liquid? Earth's mantle enables plate tectonics, so is it a liquid?
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Pitch drop experiment: http://www.thetenthwatch.com

Thanks to Meg Rosenburg for scripting and animation, Raquel Nuno for filming and Aaron White for script consultation.

How long is the coastline of Australia? One estimate is that it's about 12,500 km long. However the CIA world factbook puts the figure at more than double this, at over 25,700 km. How can there exist such different estimates for the same length of coastline? Well this is called the coastline paradox. Your estimate of how long the coastline is depends on the length of your measuring stick - the shorter the measuring stick the more detail you can capture and therefore the longer the coastline will be.

When pressure is applied to ice, its melting point is reduced so it turns to water. When the pressure is removed, however, it turns back into ice. This process is called 'regelation.' Big thanks to Art of Ice Sculptures www.icesculpture.com.au who donated the beautiful block of ice.

An atom is mostly empty space, but empty space is mostly not empty. The reason it looks empty is because electrons and photons don't interact with the stuff that is there, quark and gluon field fluctuations.
It actually takes energy to clear out space and make a true 'empty' vacuum. This seems incredibly counter-intuitive but we can make an analogy to a permanent magnet. When at low energies, like at room temperature, there is a magnetic field around the magnet due to the alignment of all the magnetic moments of the atoms. But if you add some energy to it by heating it, the particles gain thermal energy, which above the Curie temperature makes their magnetic moments randomly oriented and hence destroying the magnetic field. So in this case energy is needed to clear out the field, just as in the quantum vacuum.

Special thanks to Professor Derek Leinweber, find out more about his research here: http://bit.ly/ZZTKFP

Complete unedited interviews: http://www.youtube.com/watch?v=8dcw98B2Nzg
Trees can weigh hundreds or even thousands of tons, but where do they get this mass from? A few common answers are: the soil, water, and sunlight. But the truth is the vast majority of a dry tree's mass comes from the air - it originated as carbon dioxide

There seems to be confusion about what radiation is and where it comes from. Many people believe it is the radiation that comes directly from nuclear power plants that poses a threat to public safety. In fact it is the radioactive atoms, which can escape in the event of an explosion, that pose a safety risk. They can be scattered by the wind over hundreds of kilometres. Then they may be ingested or breathed in. If they release radiation at this point, it is damaging to the body's molecules and cells because the radiation is delivered directly to tissues.

Heisenberg's uncertainty principle tells us that it is impossible to simultaneously measure the position and momentum of a particle with infinite precision. In our everyday lives we virtually never come up against this limit, hence why it seems peculiar. In this experiment a laser is shone through a narrow slit onto a screen. As the slit is made narrower, the spot on the screen also becomes narrower. But at a certain point, the spot starts becoming wider. This is because the photons of light have been so localised at the slit that their horizontal momentum must become less well defined in order to satisfy Heisenberg's uncertainty principle.

I based this video on one by Prof. Walter Lewin of MIT: http://bit.ly/100Wk2K

Henry (MinutePhysics) has previously made a video about Heisenberg's Uncertainty Principle where he treats it as less spooky and more a consequence of waves: http://bit.ly/TV3xO5

Sixty Symbols has a great video on Planck's constant: http://bit.ly/11upebY

Thanks to the University of Sydney for hosting this experiment, especially to Tom and Ralph for their assistance getting it working.

Music: Kevin McLeod (Incompetech.com) Mirage and Danse Macabre

Lift is an important concept, not only in flying but also in sailing. This week I'm talking to Olympic Sailor, Hunter Lowden. But before I get to the physics of sailing I thought I would explain lift since it's generally poorly understood.

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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.

A quote by Einstein: A human being is a part of the whole, called by us "Universe", a part limited in time and space. He experiences himself, his thoughts and feelings as something separated from the rest — a kind of optical delusion of his consciousness. This delusion is a kind of prison for us, restricting us to our personal desires and to affection for a few persons nearest to us. Our task must be to free ourselves from this prison by widening our circle of compassion to embrace all living creatures and the whole of nature in its beauty. Nobody is able to achieve this completely, but the striving for such achievement is in itself a part of the liberation and a foundation for inner security.

I bought 10,000 shade balls and tried to swim in them.

They appear to act like a non-Newtonian fluid: rigid under high shear stress, but they flow like a liquid under low shear.

A boomerang can execute its unique roundtrip flight by making use of three fundamental physics principles: lift, relative velocity, and gyroscopic precession.

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This short was made in support of #TeamWater

💧Support Team Water Here: https://www.TeamWater.org

The biggest YouTuber collab just happened on YouTube! Hundreds of creators got together to post a video about Team Water, a fundraiser launched by @MrBeast and @MarkRober to raise $40 million to give people all over the world clean drinking water!

Special thanks to Xi Shen and his team at The Hong Kong Polytechnic University for all their help. ACS Energy Lett. 2025, 10, 7, 3419–3429.

What is the optimal strategy for bowling? #science #veritasium #physics #bowling

LED's don't get their colour from their plastic covers. The blue LED was supposed to be impossible—until a young engineer proposed a moon-shot idea.

Now, it’s true that one of the benefits of flying at 30,000 ft is a smoother ride. This is high in the troposphere, the layer in which most weather occurs. So, there’s less turbulence and fewer storms to navigate around.

But this is not the main reason that planes fly so high.