Roger's Equations

Hi Roger.

A very nice overview of the 'particle zoo'.

My biggest interest is obviously the elusive graviton. Question: is there a theoretical difference between a graviton and a virtual graviton?

As I understood it, the virtual graviton is the carrier of the 'force' of gravity, while the 'real' graviton is the quantization of gravitational waves. I'm not sure, though...

Jorrie

You are not alone in this, Jorrie.

Gravity in general, remains the Joker in this game, for the last hundred and fifty years, or even more if you extend from Maxwell's days to Newton's.

It's like, who would have thought that electromagnetics' carrier be the humble photon?

Jorrie,

Great Question. You are right that forces occur through the exchange of virtual particles. However a Real Photon and a Virtual Photon are technically both Photons, just as Real and Virtual Gravitons are both Gravitons and Real and Virtual Gluons are both Gluons, etc. Here is a relevant quote on virtual particles from wikipedia that directly addresses your question.

"This statement illustrates the difficulty of trying to distinguish between "real" and "virtual" particles as mathematically they are the same objects and it is only our definition of "reality" which is weak here. In practice, a clear distinction can be made: real photons are detected as individual particles in particle detectors whereas virtual photons are not directly detected; only their average or side-effects may be noticed, in the form of forces or (in modern language) interactions between particles."

As you can see situation is complicated and the more research I've done to try and answer your question clearly, the more questions I found. Specifically the question I would most like to answer for you (and myself) is "what is the difference between a virtual photon and a real photon?". I have an idea as to the answer but I need to read more to express it correctly. As a consequence I've decided to address this question in my next blog entry so I can give it the thoroughness it deserves.

Roger

Thanks Roger, looking forward to it!

With gravitons the situation is even worse than with photons: we can't even detect a 'real' graviton, never mind a 'virtual' one.

Jorrie

what is the differance between a subatomic particle w/b a.s.a.p

Hi Guest, you wrote: "what is the differance between a subatomic particle w/b a.s.a.p".

What exactly are you asking? What you wrote made no sense!

Jorrie

who cares

Really nice overview... Thanks...

The question that has arised from Jorrie's entry blog: "What is quantum gravity" remains: Are there "real" gravitons???... Are they quanta of the gravitational waves???... Are they different from the "virtual" gravitons (the carriers of the gravity force)???...

I look forward for more discussion on this subject...

(Also, in the same Jorrie's entry blog, I had presented some thoughts about the misterious "real" nature of the elementary particles... Just in the case that you would like to comment or present some other thoughts...)

My next blog entry will try to clear up the difference between real and virtual particles. I'm excited to delve into this subject deeper.

Hello,

My name is Edgar, and I was wondering: do force carriers produce force, or carry it? By the way, I'm doing a project for school, and I have found your blog immensely useful.