# Property Versus Not a Property?

1. Mar 3, 2015

### student34

In physics, it seems like everything is ultimately reduced to a property. I used to believe that everything reduces down to matter and energy. But it seems as though matter and energy are made up of properties.

For example, pure energy such as a photon, seems to be its parts/properties. Its spin, parity, stability etc. seem to be what it actually is.

So then what is something which isn't a property? Do we just live in a world of properties and nothing else?

2. Mar 3, 2015

### e.bar.goum

Hm, I don't think that's really how I'd put it.

Physics is the process of description. We describe every fundamental particle (and, well, everything) through the examination of their properties. For instance, an electron is a particle with rest mass 0.511 MeV/c^2, spin 1/2, charge -1 and does not carry colour charge (is a lepton). If it had other properties, we would label it with those as well. For instance, I could have an electron with a certain kinetic energy $T$, so I'd add that to the list.

There cannot be something that isn't a property of a particle, because I could always list it as a property. Then, the behaviour of the particle is described by its properties. So in some sense, yes, the world is described by properties and nothing else, but that doesn't make a property an actual thing.

3. Mar 3, 2015

### student34

Oh I see. We give properties to things. This makes sense because it seems like we can never really know exactly what something is directly except for how it interacts with its environment.

4. Mar 4, 2015

### OCR

I concur with that definition...

Here's a few more...

http://en.wikipedia.org/wiki/Physical_property
http://en.wikipedia.org/wiki/Property_(philosophy)

By definition, a thing or things, already possess properties... therefore, we can discern, perceive, or

recognize "things" from the existence of these... properties.

Though, this can also have the peculiar effect of somewhat changing the things... "existing" properties...

Last edited: Mar 4, 2015