Ketchup, My Favorite Non-Newtonian Fluid
When the ketchup won't come out of the bottle, simply tilt the bottle at about a 45 degree angle and tap it gently against the heel of your hand.
I have been using a lot of ketchup lately, ever since scoring a few bottles of the new Heinz Balsamic Vinegar version. Ketchup has many excellent qualities, of course: for one thing, it embodies a wide spectrum of flavors including salty, sweet, and umami.
For another thing, ketchup is one of the world's few examples of a fascinating physics phenomenon, non-Newtonian fluids. And the more you understand how a non-Newtonian fluid works, the more easily you will be able to get ketchup out of a glass bottle without a hitch!
