what are photons made off??

mal4mac

So we can't say what photons are made of? We can't even say if they are particles or waves or strings?

mal4mac

How do you know that? How *can* you know that? You certainly can't observe them all the time, without the observation interfering with them...

Drakkith

Nope. We can't 100% know this. However I don't believe the universe works one way when we observe something and another way when things interact without us to observe them.

harrylin

It walks like a duck, and talks a dog. The debate was then if it is a duck or a dog. I would say that a duck resembles it in the way a duck walks, and a dog resembles it in the way a dog talks.

The problem is largely in the descriptors: real "particles" such as electrons can have wave behaviour, and real waves such as sound waves can have particle behaviour.

Agerhell

For most practial applications you can forget about electromagnetic radiation being particles and just treat it as a wave as prescribed by Maxwells laws of electrodynamics. When you have light interacting with atoms or molecules they can typically only emit/absorb energy from the radiation in "chunks" corresponding to differences between energy levels in the atom/molecule.

Maybe someone can remind me of when we need to treat electomagnetic radiation as consisting of particles?

Naty1

[/QUOTE]We perceive the effects of what we don't understand and make them understandable by expanding the improbable. Hiding behind the multiple definitions only delays the truer understanding of the reality of the universe.[/QUOTE]



yes, sometimes....like dark matter and dark energy....Or "Is light a wave or a particle?" or the precession of Mercury.....that's often the start of a 'new discovery'....or attempts at least.

well some things ARE 'improbable'...like quantum theory.....but if they turn out to be
incorrect, meaning proven false, they are usually set aside and a new understanding is sought.

I think you mean 'explanations' rather than definitions...but when first discovered an initial explanation is often incomplete, incorrect or only partially correct. For example when Einstein published his theory of general relativity, he did not see the unification of space and time into spacetime [that advance insight came from his college math professor, Minkowski] nor had he even solved in own equations [the first solution came from Karl Schwarzchild, I think]. And it took Einstein some ten years to uncover what he did publish...we learn stuff in pieceparts.

I'd argue just the opposite: publishing or sharing a partial or incomplete theory or working with colleagues speeds up an improved understanding.....think of collaboration where multiple and conflicting perspectives and insights are argued out and a consensus is eventually reached.

juanrga

As is well-known in particle physics, photons are particles.

Photons, in the Standard Model of particle physics are structureless. This mean they are not made of anything, but are a basic 'building block' of nature, as fermions and quarks.

mal4mac

Lowest intensity radiation? You may have to assume photons proceed one-by-one in particle like fashion. For instance, there is a neat double-slit experiment where photons are detected one by one. Of course, the pattern they make (eventually) looks like an interference pattern, which can only (surely) come form waves. But they arrive one by one... Does even Feynman understand this stuff?

mal4mac

But the Standard Model is a ..er.. model. So it doesn't tell us *exactly* what photons are made of. So we don't know if photons are made of anything or not.

Drakkith

The model brings together all the pieces and attempts to explain how different particles interact according to laws we have derived through observation and experiment. According to the model the photon is fundamental. That doesn't mean it CANNOT be composite, only that to the best of our knowledge it is not. So when we say that a photon is a fundamental particle and not made up of anything else it is given that we mean according to the standard model and could very well be incorrect. So, according to the standard model, a photon is an electromagnetic wave that interacts according to the rules of Quantum Mechanics and has wave-like and particle-like properties.

Nabeshin

You're going to have serious issues in physics with this kind of attitude. EVERYTHING is a model, we're merely doing our best to describe how the universe functions. If you want to start asking questions about what things REALLY are like, I suggest you go hit up a philosophy forum.

juanrga

It seems that anyone knows that the Standard Model is... a model. But the rest of your post clearly indicates that you do not know what a scientific model is and what does.

harrylin

Indeed - except that if they consist of nothingness, they can't exist. And we have no reason to think that they have rest mass.