● Fascinating motion in nature
● The fascinating motion of strands

Fascinating motion in nature

These videos show why physics, the science of motion, is so captivating – be it motion in everyday life, in the universe, in machines or under the microscope. The page is not as beautiful as thisiscolossal.com, but it should be. (Disclaimer: no income is generated with this page and the work of others mentioned in it.)
 

Magnatic levitation with a dremel

A mixture of magnetism and eddy current:
explained here: 10.1103/PhysRevApplied.20.044036
 

Orbiting droplets on the ISS

Due to electrostatic attraction:
 

Looking at coffeemaking with neutron beams


 

Exception 4: a rare interview with Planck


 

Lightnings on Earth

Have a look at this fascinating real-time map for the whole world https://map.blitzortung.org.
 

Merging black holes - a simulation


 

A motor made of a few atoms


 

The most beautiful star of the world

Watch the Sun's 11-year cycle at the UV wavelength of 17 nm, from 2010 to 2020.


 

Flying spiders – a wonder of nature


 

On the difficulty of beating the juggling records

This video shows several astonishing juggling feats.

https://www.wired.com/video/watch/why-juggling-15-balls-is-almost-impossible
 

A helicoseir – driven by a robot


 

More simple motors


 

Solar eclipse from space


On 2 July 2019, filmed by the GOES satellite.
 

Exception 3: a lecture by Dirac

https://lamediateca.infn.it/mediateca/view.php?v=227
 

Exception 2: a rare interview with Dirac

 

He also speaks about the importance of understanding the fine structure constant.
 

Exception 1: a rare interview with Lemaître

 

Watch on youtube.
 

The motion when speaking

Taken with an MRI machine.


 


 

Folding and unfolding a sheet of paper

A Miura fold 

See more at https://rsos.royalsocietypublishing.org/content/2/9/150067.

This gif file shows a simple way, using tesselated parallelograms, to continuously fold and unfold a sheet of paper, the so-called Miura fold.
 

Three animations by Jason Hise: a ball glued into a mattress can rotate forever


 


 


 

A freezing soap bubble


 

The moving telescope eyes of jumping spiders

This video of a jumping spider shows how the spider moves its internal telescopic eyes:

 

The ability is presented in volume 3 of the text. To achieve precise jumps for catching prey, jumping spiders have developed built-in orientable telescopic eyes.
 

The origin of the seasons

These animated satellite photographs show how the illumination of the Earth changes during the course of a year, from equinox to equinox:

 

A detailed explanation is found at https://apod.nasa.gov/apod/ap170319.html.
 

The simplest electric train

A pretty video on how to have fun with a coil, a battery and two magnets:

 

You do not need to buy an electric train for yourself or for your children any more.

The infinite belt trick

A wonderful and surprising video:

 

Did you know that a ball glued to an infinitely flexible sheet can be rotated continuously and for ever, if done properly?

Extreme slow motion: watch light bouncing off a mirror

At last, the videos we were all waiting for: Click here to watch how a light pulse moves through space, bounces off a mirror and enters a dense medium. (https://www.nature.com/articles/nature14005.epdf?referrer_access_token=5Z1oiOBInDp2O8g2WH-mUtRgN0jAjWel9jnR3ZoTv0NZ3EmFUOGYN0jLvU2WgUypCBLJdJFQiaxL30mA5vzOE6aU-cyBtfpDNKUwtqWklRawbNbIWqcwxODa1HC4ouM3)

Amplifying motion effects in everyday life

For a talk by Michael Rubinstein full of surprising effects, see this link to his TED presentation. He shows how to observe and visualize the heart beat through skin colour changes, how to detect sound through shape change of plastic bags or of plant leaves, and how to detect and visualize tiny motions of everyday bodies.

The Sun's surface and its fascinating motion


 

The chain fountain: the weird motion of a chain of beads

 
Steve Mould discovered the effect in 2013. See also the article at his site https://stevemould.com.

The motion and the growth of bacterial flagella

The fascinating motion of bacterial flagella, including the change of direction, is found on the page https://www.fbs.osaka-u.ac.jp/labs/namba/npn . Click here to download the mpeg file.

The incredible growth of bacterial flagella is also found on the page https://www.fbs.osaka-u.ac.jp/labs/namba/npn . Click here to download the mpeg file.

The diversity of bacterial motion

The fascinating motion of different types of bacteria can be watched on the film https://bio1151.nicerweb.com/med/Vid/Johnson4e/Wmv/Bacterial_Diversity.wmv.

Fun with mechanical motion

 
Accelerating and decelerating wheels helps moving across a surface, even if the wheels do not touch the surface at all.

How atoms switch orientation inside a magnet

 
This film, taken by Hendryk Richert at www.matesy.de shows how the magnetic regions in a material change when a magnet approaches. The film was simply made using a handheld magnet, a magneto-optic coating on a glass substrate and a usual video camera.

How geostationary satellites remain fixed even if the stars move

Geostationary satellites in the Swiss Alps were filmed by Michael Kunze. The stationary satellites are visible along a line going to the top left corner.

How stars orbit "our" black hole

Click here for a range of fascinating videos showing the motion, during ten years, of the stars around the huge black hole at the centre of our Galaxy. Without that black hole, the Milky Way and thus our Earth would not exist. The film was made with ESA telescopes.

Flying around the Earth is worth it

 
The film shows the beauty of our planet. More details can be found on APOD and even more on the author page https://randomphotons.com/alone.

How atoms move

 
This film shows the motion of a number of atoms, and the way they change position. More details here.

The flickering of stars at night

Click here to see the difference between a star and a planet in the night sky. It is worth it.

The wave properties of matter

Click here to see quantum physics in action: a visualisation of the double split experiment for matter. This might be the best way to understand quantum theory.

More videos are found inside the free textbook

The pdf files of the Motion Mountain textbook also feature embedded films of moving electrons made visible in liquid helium, of the astonishing solitons in water, of the elementary particles inside atoms, about the motion of cilia that determine that our heart grows on the left side of our body, the world seen from a relativistic car, and much more. Just download the pdf files to see these videos; they all run inside Adobe Reader.

Science entertainment

Some people try to make video shows out of physics. Two examples are https://www.youtube.com/user/Vsauce and https://www.youtube.com/user/1veritasium. You might like them.

Top

The fascinating motion of strands

The following is a collection of animations about the strand model, a research topic presented here.

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Basic belt trick animations by Jason Hise

This animation shows how, in the strand conjecture, an elementary particle is conjectured to be continuously rotating, despite its tethers:

 

The next animation shows how, in the strand conjecture, a (tiny) black hole is conjectured to be continuously rotating.

 

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The belt trick as proof of the spin-statistics theorem – two videos.

Spin 1/2 particles are fermions, because belts with buckles behave like fermions: a double exchange – but not a single one – of particle position (i.e., of belt buckles) is equivalent to no exchange at all. This is the defining property of fermions.

This unique animation is copyright and courtesy of Antonio Martos. Assume that the belts cannot be observed, but the square buckles can, and that they represent particles. The animation shows that two particles (the two square buckles) that are connected to infinity by belts, can return to the original situation by fluctuations, but only if they are switched in position twice (and not just once). Such particles thus fulfil the defining property of fermions. (For the opposite case, that of bosons, a simple exchange would already lead to the identical situation.) You can repeat the trick at home, using paper strips. The trick is shown here with two belts per particle/buckle, but the untangling works with any number of belts! Together, this and the next animation are the essential parts of the proof that spin 1/2 particles are fermions. This result is called the spin-statistics theorem.

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Belts with buckles also behave like spin 1/2 particles: indeed, two full rotations – but not a single one – are equivalent to no rotation at all. This is the defining property of spin 1/2:

This beautiful animation is copyright and courtesy of Antonio Martos. Assume that the belt cannot be observed, but the square belt buckle can, and that it represents a particle. The animation then shows that such a particle (the square buckle) can return to the starting position after rotation by 4 pi (and not after 2 pi). Such a `belted' particle thus fulfills the defining property of a spin 1/2 particle: rotating it by 4 pi is equivalent to no rotation at all. (The belt thus represents the spinor wave function; for example, a 2 pi rotation leads to a twist; this means a change of the sign of the wave function. A 4 pi rotation has no influence on the wave function.) You can repeat the trick at home, with a paper strip. The equivalence is shown here with two belts attached to the buckle, but the trick works with any positive number of belts! Can you find a proof for this? By the way, such belted buckles - together with equivalent constructs made of ropes or tubes - are the only possible systems that show the spin 1/2 property.

Parity violation

The weak interaction acts differently on right-handed and on left-handed particles.

In the strand conjecture, the weak interaction is the exchange of pokes, i.e., the exchange of second Reidemeister moves. At the same time, a fermion in a strand conjecture is modelled by a tangle with a rotating core. In particular, an antiparticle tangle is the mirror of a particle tangle, rotating in opposite direction.

In the strand conjecture, the weak interaction effectively induces pokes on a fermion tangle. The following two videos by Jason Hise show how this differs for right- and left-handed particles. Alternatively, the videos can also be seen to show the two extreme forms of the belt trick.

 

You can also click here for an infinite loop version.

 

You can also click here for an infinite loop version.

This is a fun combination of both above motions:

 

You can also click here for an infinite loop version.

And two mechanical realizations, with a construction kit: