PeterDonis, two respondents clearly deny your claim. I can't accept your argument. Sorry.
For references, please see my two other forum threads. I only have three or four threads. Not hard to do, if threads can be traced by username. I am new to this site, so please forgive my ignorance on the mechanics of how to recall threads. I am a complete newbie, I can't navigate easily.
One quote from an answer to me to an earlier question:
"In the standard model, particles come in pairs. We have the electron, of course, and we must have an anti-electron (aka the positron), which has the same mass as the electron but a positive charge. Even though the positron is called "anti-matter", you could just as easily call the positron matter and the electron antimatter. The important point is that the electron and positron have a tendency to annihilate each other."
The other quote:
(They talk about photons and gravitons)
BadgerBadger92 said:
I thought their properties would be the the exact opposite
What properties would you expect to be opposite? They have no charge, no magnetic moment, etc. Pretty much the only non-zero property they have is helicity, and the helicities of particles and anti-particles is the same anyway. So the properties of a photon and anti-photon are opposites... but as the properties are equal to 0 we just get the same particle back as we started from.
I hope this answers your incredulity why I rejected your answer.
Remember, I am a complete dilettante in quantum physics and in relativity physics, but I apply logic to what I read.
According to the above, anti-particles and particles annihilate each other; and photons and gravitons are anti-particles to each other.
While I admit you may be right, I can't make that judgment. (You claimed matter and anti-matter don't annihilate each other and photons and gravitons are not each other's anti-particles). You have to duke it out :-) with the originators of the above quotes.
I also understand standard English; misplaced antecedents, or unclear relations between pronouns and their antecedents may make the descriptions inaccurate. I read what is written, I don't add or subtract, I assume that the writer writes what he means. This may be naivety on my part, yet what else can I do when I read on a topic I have zero knowledge about?