What Are We And The Universe Made Out Of?

Have you ever looked at something and wondered what it was made out of? Why should you? Well it might be a nice fact to know to impress your neighbours or perhaps your friends or even the butcher. Then again it might just be interesting.

 Everybody learns about molecules and atoms at school and in high school about quarks perhaps. Let us start at baby level and then work our way up to almost science level  whatever that is.

Molecules are small particles that make up all living and non-living things. They are made up of even tinier particles called atoms. Moving things are made from only about 25 of more than 100 known atoms in the universe. Molecules are made from as few as two atoms to hundreds of millions of atoms. 

Flu Molecule

Molecules are so small that there are more molecules in your body than there are stars in the universe! ( no I didn’t count them).

What’s so special about molecules in your body and in other living things? Each molecule has a unique shape that allows it to interact with other molecules. The interactions, getting together, between molecules let us as well as bacteria, elephants, and other living things  move, sense, reproduce and do the things that keep all living creatures alive.

So if a molecule is made up of atoms then what are they? (Do you really want to know?) A typical atom consists of a nucleus composed of positively charged protons and neutral neutrons surrounded by a cloud of orbiting negatively charged electrons.  The proton is located in the center (or nucleus) of an atom, each atom has at least one proton. The neutron is locatated in the atomic nucleus ( and why not?). The electron is a very small particle located outside the nucleus. Because they move at speeds near the speed of light the precise location of electrons is hard to pin down. 

So what is this quark thing? Quarks are a type of particle that make up matter. Look around you…all of the matter that you see is made up of

A Molecule

protons and neutrons, and these particles are composed of quarks. Quarks and Leptons are the building blocks which build up matter, i.e., they are seen as the “elementary particles”

 In the present standard model, there are six “flavors” of quarks-

Up (symbol: u), down (d), charm(c), strange (s), top (t) and bottom (b). 

Up and down quarks have the lowest masses of all quarks, and thus are generally stable and very common in the universe. The other quarks are much more massive, and will rapidly decay into the lighter up and down quarks. Because of this, the heavier charm, strange, top and bottom quarks can only be produced in high energy collisions, such as in particle accelerators and cosmic rays.   

Every quark has an opposite called antimatter. Almost the entire universe is full of matter and this is a great mystery as antimatter doesn’t seem to exist when it should exist. A good website about antimatter if you are interested is here.

For many months, the GEO600 (a laser interferometer,  whatever that is?)team-members had been scratching their heads over inexplicable noise that is plaguing their giant detector. Then, out of the blue, a researcher approached them with an explanation. In fact, he had even predicted the noise before he knew they were detecting it.

 GEO600 stumbled upon the fundamental limit of space-time – the point where space-time stops behaving like the smooth continuum Einstein described and instead dissolves into “grains”, just as a newspaper photograph dissolves into dots as you zoom in. or like the pixels on your screen that make up this post.

Well thats about as low as we go in this post as the small stuff as it gets smaller now gets truly wacky. The Planck length, for instance, is the scale at which classical ideas about gravity and space-time just stop being valid, and quantum effects dominate. This is the ‘quantum of length’, the smallest measurement of length with any meaning. 

Watch this space for the next thrilling episode of small, very small and really, really small stuff.