Are electrons/photons/positrons the smallest quantifiable object?

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Problem Statement: Are electrons/photons/positrons the smallest quantifiable object?
Relevant Equations: NA

Would it be correct to say that electrons, positrons and photons are the smallest object with mass? If so would it also be correct to say that they are the primary "holders" of energy in the Universe and are the main cause of transference of energy between particles?

I am just starting an A level in physics so a simplified response for a current simple mind would be appreciated. I know, it frustrates my advanced physics friends. ;)
 
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Trooper149 said:
Would it be correct to say that electrons, positrons and photons are the smallest object with mass?

Photons, no, as they are massless. And the concept of size when it comes to fundamental particles is problematic, as they aren't solid spheres with non-zero size. Put simply, you will always find a fundamental particle in one spot, and that particular spot can be as small as you can get your detector to see. So if an electron hits a pixel in a sensor and stops, you can make your pixel as small as you like and you will still find that the electron is found in one and only one pixel (as long as it's not traveling too fast and other experimental details). You'll never reach a point where the electron can only be found in two or more pixels at the same time like what would happen if it was a solid object with non-zero size.

Trooper149 said:
If so would it also be correct to say that they are the primary "holders" of energy in the Universe and are the main cause of transference of energy between particles?

No. Energy is a fairly complicated topic, but fundamental particles can't really be said to 'hold' energy in and of themselves. It's more like energy is found in systems of particles. As for transferring energy, that boils down to the interaction of particles with force-carrying gauge bosons (photons, gluons, and W&Z bosons).

Trooper149 said:
I know, it frustrates my advanced physics friends. ;)

I can't say much about your friends, but you won't frustrate anyone around here by asking questions. :wink:
 
Trooper149 said:
I am just starting an A level in physics so a simplified response for a current simple mind would be appreciated.
The electron (and its antimatter partner the positron) are members of a class of particles called leptons. Photons are in an entirely different category.

One thing to wrap your head around are properties such as electric charge, mass, and size. It seems the notion of a particle without an electric charge is easy to accept. But particles can also have a zero size or a zero mass. These notions seem harder to accept, but it is best if you think of mass and size as properties.
 
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Trooper149 said:
Problem Statement: Are electrons/photons/positrons the smallest quantifiable object?
Relevant Equations: NA

Would it be correct to say that electrons, positrons and photons are the smallest object with mass? If so would it also be correct to say that they are the primary "holders" of energy in the Universe and are the main cause of transference of energy between particles?

What do you mean by "object with mass"? It is odd to include photons in that because photons are massless.

If you wish to know about "elementary particles" within the Standard Model of elementary particle physics, then look at this chart. This is what we know as of right now to be the most basic, elementary particles.

http://www.cpepweb.org/images/2014-fund-chart.jpg
2014-fund-chart.jpg


Zz.