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Today, TEDxCERN and TED-Ed have unveiled the first of 5 animated lessons specially developed by CERN scientists for TEDxCERN and brought to life by the talented animators at TED-Ed: “The beginning of the universe, for beginners.”
The lesson, which you can watch above(!) and at ed.ted.com, was conceived by CERN physicist Tom Whyntie and explains how cosmologists and particle physicists explore questions like, “How did the universe begin? How is it expanding?” by replicating the heat, energy, and activity of the first few seconds of our universe, right after the Big Bang.
As I watched this miniature world self-assemble on my windshield like an alien landscape, I wondered about the physics behind these patterns. I learned later that these patterns of ice are related to a rich and very active current area of research in math and physics known as universality. The key mathematical principles that belie these intricate patterns lead us to some unexpected places…
A pretty spectacular science experiment: how to make an Incredible Egg Geode.
Your egg geode is formed through a process called sedimentation. The heated alum solution contains suspended particles of alum powder and as the solution cools, these particles of alum begin settling. When the alum particles settle towards the bottom of the beaker or glass, they begin crystallizing. With the alum-covered egg at the bottom, the alum particles from the solution begin attaching themselves to the egg. Covering your egg in alum powder beforehand gives the suspended alum particles a surface to which they can more readily attach themselves. The particles that settle onto the surface of the egg crystallize, and you will also see crystallization on the bottom and sides of the beaker or glass.
For this experiment, you can use a bicycle pump with a rubber stopper attachment, rubbing alcohol and a clear 1 liter bottle. Don’t forget goggles and some adult supervision! Steve Spangler’s Science has more:
The reason the rubbing alcohol forms a more visible cloud is because alcohol evaporates more quickly than water. Alcohol molecules have weaker bonds than water molecules, so they let go of each other more easily. Since there are more evaporated alcohol molecules in the bottle, there are also more molecules able to condense. This is why you can see the alcohol cloud more clearly than the water cloud.
Clouds on Earth form when warm air rises and its pressure is reduced. The air expands and cools, and clouds form as the temperature drops below the dew point. Invisible particles in the air in the form of pollution, smoke, dust or even tiny particles of dirt help form a nucleus on which the water molecules can attach.