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How cool is cold: strange things that happen at ultraow temperatures

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Slides for the demo I am giving at my kids' school, Browns River Middle School on ultralow temperature physics

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Page 1: How cool is cold: strange things that happen at ultraow temperatures

Anita de Waard(a.k.a Sebastiaan’s Mom)BRMS, November 21 2013

How cool cold can be:Strange things that happen at ultralow temperatures.

Page 2: How cool is cold: strange things that happen at ultraow temperatures

What is cold?

Page 3: How cool is cold: strange things that happen at ultraow temperatures

Three temperature scales:

Page 4: How cool is cold: strange things that happen at ultraow temperatures

Weird things happen at low temperatures:

A mental state is found in victims of hypothermia, in which they go from “cold stupid” to “cold crazy”. Delusions and hallucinations are commonly reported. Sometimes, this takes the form of an out-of-body experience where the victims see themselves from outside. One hypothermia victim who was found partially undressed said that he “felt like a bug”. When asked to explain what he meant by this “he became agitated and upset”. http://www.forteantimes.com/strangedays/science/2806/cold_cases.html

Page 5: How cool is cold: strange things that happen at ultraow temperatures

When you get even colder, they get even weirder:

• Liquid nitrogen demonstration

Page 6: How cool is cold: strange things that happen at ultraow temperatures

When you get even colder, they get even weirder:

• Superfluidity is a macroscopic quantum phenomenon: things of the size of our world (macroscopic) behave according to the laws of very small things (microscopic)

• “Typically, this means distances of 100 nanometers (10−7 meters) or less, or matter at very low temperatures.”

• Superfluid helium video

Page 7: How cool is cold: strange things that happen at ultraow temperatures

I worked on superfluid helium:

• In Leiden, while measuring superfluid helium films (when I broke a capillary…)

• And in Moscow, where I learned towork with He-III at mKelvin temperatures (and put my finger on a cryostat with helium to stop the flow…)

Page 8: How cool is cold: strange things that happen at ultraow temperatures

Any questions?

Anita de [email protected]