Re: Query: Re: Balloon-Borne Instrument Collects Antimatter

Anders Sandberg (
20 Aug 1999 21:12:12 +0200

"Clint O'Dell" <> writes:

> This whole anti-matter travels backward in time is a little
> confusing to me.

Antimatter doesn't break the laws of entropy; when a physicist says antiparticles move backwards in time he doesn't mean that you can detect that an antimatter generator is going to be turned on in the future by detecting antiparticles, but rather that antiparticles can be viewed as an ordinary particle going backwards in time. Hmm, that may not have made much sense.

The point is, a piece of antimatter will behave just like ordinary matter when it comes to entropy - an anti-ice cone will melt when warmed by a laser just like an ordinary ice-cone, and a bowl of antipasta will cool off if left alone. The component particles can be viewed as ordinary particles moving backwards in time, but the antimatter doesn't do anything stranger than expected.

> My perception of time is an infinite amount of "NOWs". The reason we 'seem'
> to be going forward in time is because we are remembering what happened
> first. We remember events in order. I'm not sure if I'm being clear here
> or not. It's real hard to word.

I know. I prefer Einstein's view of space-time as a big crystaline block, with "now" a plane cutting through it - but you can angle and move the "now" arbitrarily.

> Can some please help this physics layman to understand what is meant by the
> word "time" as applied to physics?

Oh, that is hard. Time is such a strange concept. I suggest that looking up some relativity theory might help, even if it is not going to feel helpful at first. *might* help.

Anders Sandberg                                      Towards Ascension!                  
GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y