[Aeris (OP)]

So the original question that used to be here was about what the laws of physics are, but... I realized that I could not for the life of me think of a decent way to word what I was actually asking, not to mention the question itself didn't really make a lot of sense when spoken out loud. So I decided to change the question to be about something a little less ambiguous. Photons. Just gonna jump right into this one again instead of saying anything else.

1. So... Photons lack mass (you know, the thing that gives an object its weight and the ability to impart a force onto another object), yet they carry momentum capable of... moving solid objects? What? How on Earth does this work exactly? How can something with no mass, carry momentum and more importantly, where does the momentum even come from?
2. What exactly are Photonic Molecules?
3. Photons are capable of transferring light (electromagnetic energy) as radiation, but why is light the only form of energy that has the ability to move as a particle? Why don't other forms of kinetic energy like heat and sound have their own particles to move as?
4. When the Sun radiates its energy as a storm of particles, many of them travel throughout space, all the way to the planets around it such as Earth, Mars, Venus and the Moon. Once the energy reaches those planets, they radiate an equal amount of energy away back into space in the form of infrared photons and useless radiation. What about the particles that don't reach anything though, and bolt of into the unobservable universe? There's no air or stone to steal the particles energy away, so do they hold onto that energy forever, or do they eventually loose it through a radiation-like process?
5. How feasible on a scale of 1 to 10 (1 being not at all feasible and 10 being very feasible) is the idea of a Photon blaster/cannon? Think of something like Star Trek's particle cannons, but with Photons instead of electrons/protons. Could we realistically weaponize Photons like this? Just for the record, I know I'm more or less describing a laser, but I was thinking more along the lines of Star War's blasters, or Iron Man's Repulsors. Would something like THAT be possible?     

     

[Origin]

They seem to be woven into the very fabric of the universe, but what do they manifest as?

Not sure what you mean by that.  For instance the conservation of energy is manifested as energy being conserved.

Did they always exist, or did the big bang create them?

Physical laws came into existence as a result of the big bang.

Let me put it in a way that's easy to understand. Some people on Earth have a genetic disability called Autism, which manifests in the brain (which is different from a neurotypical's brain) and brings about said people's difficulty in social engagement, enhanced sensitivity to bright lights and loud sounds, increased difficulty in focusing on others, etc. If the laws of physics are the effects of Autism, what is the thing it manifests as and brings those effects about (does this analogy make any sense? let me know if it doesn't)?   

That analogy doesn't help, it complicates and muddies the water.

[chiralSPO]

Ok, so remember that time I asked about what energy is? Do you also remember the time I asked about why Conservation of Energy can't be violated? Well consider this question a fusion between those two.

The laws of physics, as everyone already knows, are statements made about the way the universe works based on carefully-calculated observations. They define the line between what's possible and impossible in our lives, and as far as we're currently concerned, cannot be broken in any way whatsoever.

But like, what are they exactly?

The universe is complex. Far too complex for our simple meatbrains to comprehend. Luckily, we are resourceful, and have figured out how to imagine simplified "models" of the universe: where we propose sets of "rules" for a "game" and if the "game" mimics what we see in the universe, then it might be a useful model. It is important to point out that all models are wrong. (they are vast oversimplifications) But it doesn't matter if the models are not an accurate depiction of what is "truly" happening, they are still very useful.


The "laws of physics" are rules that it appears the universe ALWAYS obeys. Said another way: every model of the universe that gives good predictions has these sets of rules in common. (Note: it is totally possible to have models that are useful that don't take some of these into account, ie I don't need to use relativistic quantum mechanics to predict that a watermelon will roll off a sloped table.)

The laws of physics aren't like societal laws that are made by those in power and, if broken, result in you going to prison. They seem to be woven into the very fabric of the universe, but what do they manifest as?

I'm not quite sure what you mean. They were deduced from observation of how the universe is. They manifest as how the universe is. But that is circular, so let's jut focus on the first one: they were deduced from how the universe is.

 

Did they always exist, or did the big bang create them?

It's hard to say anything about "before the big bang"

Let me put it in a way that's easy to understand. Some people on Earth have a genetic disability called Autism...

how does that make it any easier to understand? autism is an emergent property of extremely complex systems (and as I understand it, there are multiple causes and forms of autism, which may be incorrectly lumped together, but that is a subject for a different thread)

[alancalverd]

Physics is the business of constructing mathematical models of things that happen. And if you are a structural or civil engineer, also models of things we don't want to happen!

The laws of physics are those models that seem to apply to every event, to such a degree of precision that we consider them immutable and universal. At least until we come up with a measurement that violates them.

So we have conservation of energy as a law, except that we can transmute mass and energy in exceptional circumstances so we need to redraft the law in terms of relativistic mechanics, and so far the relativistic corrections to newtonian mechanics seem to hold to a very high degree of precision. Conservation of charge and momentum seem to be very precise laws.

Inverse square laws like gravitation and the intensity of radiation are more idealised than we can measure, because every body that sucks or radiates is necessarily larger than a mathematical point source, but it is clear that reality approximates to the law for small sources and large distances.

It's a pity that the word "law" has survived from the days when it was presumed that events in the universe were ordained by an external entity and thus ran like a dictatorship. It would make more logical sense to call them "best working approximations", thus recognising that they are descriptive and predictive, not prescriptive.

Not all laws are equations. The most fundamental and annoying inequality is  ΔS > 0, i.e. entropy always increases.

[evan_au]

Just What Exactly are the Laws of Physics?

Well, we can't exactly tell you, because we haven't worked them all out, yet.

https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics

[Origin]

First of all, deleting your OP and writing another OP is an absurd thing to do!!!  All the original answers make no sense now.  Start another thread next time.

How can something with no mass, carry momentum and more importantly, where does the momentum even come from?

The momentum comes from the energy of the photon.

Photons are capable of transferring light (electromagnetic energy) as radiation

No, photons are light.

but why is light the only form of energy that has the ability to move as a particle?

Photons are not a form of energy. 
 

There's no air or stone to steal the particles energy away, so do they hold onto that energy forever

If you are talking about the solar wind, the yes they go on forever if they never interact with anything.

How feasible on a scale of 1 to 10 (1 being not at all feasible and 10 being very feasible) is the idea of a Photon blaster/cannon? Think of something like Star Trek's particle cannons, but with Photons instead of electrons/protons. Could we realistically weaponize Photons like this? 

10.  We call it a laser.

[Eternal Student]

Hi.

You might be worrying about your posts too much, Aeris.
    Realistically, hardly anyone is likely to ever look at the thread again after it gets old.   You've gone back and edited your Original post (OP) for very little reason.  When I started on this forum, I thought posts might be quite important and people might read them for a long time after they were finished - but it's not like that.
    The number of regular members using this forum is about one dozen people per day.  Most of the rest of the views that are reported in the statistics are likely to be people who were curious about the forum but not really about your particular post and there's always plenty of people who were keen to see if they could just drop some advertising into something you've written.
     I'm inclined to support the spirit of what @Origin has said.  Starting a new thread is going to work better rather than completely re-writing the OP.  Some of the people who have already replied may not even realise that the OP has shifted it's nature and so they won't even know there are new questions.

How can something with no mass, carry momentum and more importantly, where does the momentum even come from?

   It might be worth turning this question around a little.   Don't be so certain that a photon has 0 mass in any real sense .   All we know is that in any inertial reference frame a photon has momentum and energy.
    Just consider what the rest mass of a photon might actually be.  We say that it is 0  (zero)   but we have no way of measuring it directly.   To measure the rest mass of a particle we need to be in a frame of reference where the particle is at rest.   There isn't a rest frame for a photon.  There is no inertial reference frame where a photon would be at rest, it must always have velocity c  in any inertial reference frame.  Whatever the qunatity we call the "rest mass" of a photon might be it is a bit abstract, it isn't telling us anything about the mass of a photon when it's at rest.
     We have equations like this from Special relativity:
E²  =  m₀².c⁴  + p².c²    and from this we can infer that the quantity  m₀   must be 0 for a photon.   We call this the rest mass but in the case of a photon, it's just a quantity,  an abstract quantity.

    So, we could answer your question by saying there is a fault in the question:  You are attempting to use a simple expression for momentum like  mv    but  the mass you need to know, m,  is not 0,  it is undetermined.   The rest mass of a photon is 0 but this is an abstract quantity and not a description of the mass of a photon when it's at rest (despite the name "rest mass").

Best Wishes.

[Aeris (OP)]

First of all, deleting your OP and writing another OP is an absurd thing to do!!!  All the original answers make no sense now.  Start another thread next time.

I admit in retrospect, it was a poorly thought out idea. I just didn't wanna a question that made no sense when spoken out loud (I'll admit, even I wasn't 100% certain what it was I was originally asking) to sit here and collect dust. That... and the website physically would not allow me to delete the question for some weird reason. I'll keep this in mind for next time though, don't you worry.

Quote The momentum comes from the energy of the photon.

That doesn't make an atom of sense. Are you saying there's some kind of energy to matter conversion happening during a photon's journey from one location to another? Is energy being converted directly into momentum (how the actual duck would THAT even work?)? What does this answer mean exactly?

Quote No, photons are light.

Quote Photons are not a form of energy. 

This feels like a contradiction. You say Photons themselves are light, but then you immediately say shortly afterwards that they aren't a form of energy. Now, you could argue that light itself isn't a form of energy, but, like, there's absolutely no reason at all to think that, or did you just forget about the existence of solar panels? Eternal Student has also stated that Photons aren't made out of light energy, but are rather carriers of it so... which is the correct answer then? Are photons made out of energy, or do they merely carry it? Is light itself a form of energy, or is it something distinct from energy and matter entirely?
     
Quote We call it a laser.

Ok, yeah. I deserve this for not being descriptive enough. I know that real-life laser beams are capable of inducing blindness and can even defect/ignite matter through a conversion of light energy to thermal energy. Those weren't the kind of light-based weapons I had in mind though. I was referring to something akin to the blaster from the Star Wars franchise. You know, blasts of concussive light capable of imparting the same level of force onto their victims as a bullet, melting through metallic matter in an instant and levelling entire cities/planets. Is something like THAT possible?

[Aeris (OP)]

Hi.

You might be worrying about your posts too much, Aeris.
    Realistically, hardly anyone is likely to ever look at the thread again after it gets old.   You've gone back and edited your Original post (OP) for very little reason.  When I started on this forum, I thought posts might be quite important and people might read them for a long time after they were finished - but it's not like that.
    The number of regular members using this forum is about one dozen people per day.  Most of the rest of the views that are reported in the statistics are likely to be people who were curious about the forum but not really about your particular post and there's always plenty of people who were keen to see if they could just drop some advertising into something you've written.
     I'm inclined to support the spirit of what @Origin has said.  Starting a new thread is going to work better rather than completely re-writing the OP.  Some of the people who have already replied may not even realise that the OP has shifted it's nature and so they won't even know there are new questions.

Really? I wasn't under that impression at all. Tons of people have come to give their answers to my past questions (my question about the true nature of energy is like 3 pages long with over 40 replies). I've also never seen a single person drop even a little bit of advertisement into their answer once, but maybe I didn't look hard enough for it at the time.

I agree with your second paragraph though. Changing the question from the ground-up instead of asking a new one was very silly of me and I promise never to do it again. You have my word on that (like, seriously the words telling you I will never do this again are right there on your screen and not going away anytime soon).


Quote It might be worth turning this question around a little.   Don't be so certain that a photon has 0 mass in any real sense .   All we know is that in any inertial reference frame a photon has momentum and energy.
    Just consider what the rest mass of a photon might actually be.  We say that it is 0  (zero)   but we have no way of measuring it directly.   To measure the rest mass of a particle we need to be in a frame of reference where the particle is at rest.   There isn't a rest frame for a photon.  There is no inertial reference frame where a photon would be at rest, it must always have velocity c  in any inertial reference frame.  Whatever the qunatity we call the "rest mass" of a photon might be it is a bit abstract, it isn't telling us anything about the mass of a photon when it's at rest.
     We have equations like this from Special relativity:
E²  =  m₀².c⁴  + p².c²    and from this we can infer that the quantity  m₀   must be 0 for a photon.   We call this the rest mass but in the case of a photon, it's just a quantity,  an abstract quantity.

    So, we could answer your question by saying there is a fault in the question:  You are attempting to use a simple expression for momentum like  mv    but  the mass you need to know, m,  is not 0,  it is undetermined.   The rest mass of a photon is 0 but this is an abstract quantity and not a description of the mass of a photon when it's at rest (despite the name "rest mass").

Best Wishes.

Yeah... I'm gonna level with you buddy. I don't understand a word of what you just said. The only thing (I think) I understood was that the question was inherently flawed due to the way I phrased it. Could you please be so kind as to simplify your answer for me?

[Eternal Student]

Hi.

The only thing (I think) I understood was that the question was inherently flawed

   I need to explain what I meant.

   There's no problem with your question.   There's no "right way" to ask a question, it's your question.  You should ask whatever it is you want to ask.

   When I said there's a flaw in the question, that's not your fault.  It's the way physicist use the term "rest mass" and all the things you would have seen elsewhere and in school.
    If you just pull the term "rest mass" apart as if it's a phrase in the English Language then it would mean the mass that a photon has when it's at rest.   However, this is not something sensible.   It would have been better if Physicist's had always called this thing  "the invariant mass" because then everyone would know it was something special with a precise definition.    However, that is not my decision to make.  Historically, "the invariant mass" has been called the "rest mass".   All we can do now is to make it clear that this isn't the mass that a photon would have when it's at rest.

   I've decided to cut down my original post, it was far too long and you probably aren't that interested in the details anyway.
   Special relativity demands that light will always travel at the speed of light, c  (in any inertial frame - but I'm not going to discuss inertial frames here - so I'll just say  "in all sensible situations").  So it is not possible for a photon to be stationary in any sensible situation.  In particular, we have no hope of measuring the mass of a photon when it is at rest because it just can never be at rest.
     Therefore the "rest mass" of a photon is just an abstract quantity and we should really call it the "the invariant mass" so that everyone knows it's an abstract, generalised or ideal thing and not something we can actually measure directly.

     The next important thing is that you have probably read or been taught that    momentum = mass x velocity.    This is probably why you are concerned about the photon having 0 mass   but still having a non-zero momentum.
     There are at least two ways we can address this issue.   The first is to say that many physicists were also troubled about this.  It's a very good question to ask and something that does seem quite puzzling.
      [** See LATE EDITING, below]    Physicist's were sufficiently determined to maintain this simple concept of momentum that they developed a quantity called "relativistic mass".   They accepted that the invariant mass of a photon wasn't anything you could ever really measure, it certainly wasn't going to be measured as the mass of the particle when it was at rest in some inertial frame.  So they determined that the invariant mass wasn't something that should be used in that formula     momentum = mv.     The "relativistic mass" is something you can almost measure, you can certainly infer it's value from some simple observations, and this is what you needed in that formula.    So we could answer your question by saying that although a photon has 0 invariant mass   (or  0 "rest mass"),  it has a non-zero relativistic mass  and that's what's needed to allow it to have momentum.   [**]

      More recently, the idea of "relativistic mass" has gone out of favour.  It's best if we just don't use it and only use the quantity called invariant mass.  In this situation we still have a problem  with the simple formula   momentum = mv   but we're not encouraged to modify the mass term, m in order to fix that equation.   We have to accept that the momentum is NOT given by the expression  mv.     Instead the momentum of a particle is obtained from a more complicated structure called the four-momentum.    You probably don't want a full explanation of what a four-momentum is  (there are references on Wikipedia and/or textbooks  and you could always ask if you really did want to know about this more complicated structure).
     Anyway, we could now answer your question by the second method:   We could state that momentum isn't exactly what you thought it was or might have been taught at school.  It never really was given by the simple expression    momentum = mv.   That expression is just an approximation that holds well for slow particles.   Momentum was really obtained from a more complicated structure, the four-momentum, and there was never any requirement for the invariant mass to be non-zero in order for a particle to have a non-zero momentum.
     
   Let's put this directly into action on the original question:

So... Photons lack mass (you know, the thing that gives an object its weight and the ability to impart a force onto another object), yet they carry momentum capable of... moving solid objects? What? How on Earth does this work exactly? How can something with no mass, carry momentum and more importantly, where does the momentum even come from?

  1.   Photons have 0 invariant mass but this is just an abstract thing.  We could never directly measure the mass of the photon when it's at rest.  So the mass of a photon is actually undetermined, all we know is it's "invariant mass" and, if we wish to calculate it and use it, "the relativistic mass".
  2.   Mass doesn't give a particle weight.   This requires gravity and gravity acts on any source of something we often call "stress-energy" or "energy-momentum"  -  mass is just one common example of this "stress-energy".  To phrase it another way, mass is NOT required.  Anything with momentum and energy will be a source of gravity and anything with momentum and energy will be influenced by gravity.
  3.   The ability to impart a force onto another object is granted by many things.  You were presumably talking about direct physical collision and the transfer of momentum.  This only requires that the incident object has some momentum and in the formal definition of momentum  (from four-momentum) this does not require the incident particle to have a positive invariant mass.  Non-zero mass is only required in the simple model of momentum that might be taught in school and/or applies adequately for slow particles.
  4.    "How on earth does this work exactly?"  It rests upon a decision to give up the school definition of momentum and recognise that it has limits.  You can't save the school definition of momentum = mv  when considering fast particles.  You can either "tweak it" by using a quantity called "relativistic mass" or else directly utilise a better definition of momentum.

Best Wishes.

LATE EDITING    The paragraph marked   [**]  at the start and end is not intended to be a histroically accurate description of the development of the term "relativistic mass".  It is just a rapid connection between an issue presented by the OP  and  similar issues that would trouble many physicists.  See Post #22 and #23 for discussion.

[Aeris (OP)]

@Eternal Student

Thank you for rewording your answer for me. I understand it a lot better now

[alancalverd]

IIRC Einstein's argument was a lot simpler.

Imagine a box full of electromagnetic energy - i.e. photons bouncing off the walls.
Allow one side of the box to move.
Common sense (and a few very clever observations) says that it will move outwards, reducing the energy density inside  the box. 
So we have imparted some momentum to the wall - or the solar sail
Conservation of momentum says that if we have added mv to the wall, we must have  added -mv to the contents of the box
Thus photons can impart momentum, so they must have momentum.
 

[Aeris (OP)]

IIRC Einstein's argument was a lot simpler.

Imagine a box full of electromagnetic energy - i.e. photons bouncing off the walls.
Allow one side of the box to move.
Common sense (and a few very clever observations) says that it will move outwards, reducing the energy density inside  the box. 
So we have imparted some momentum to the wall - or the solar sail
Conservation of momentum says that if we have added mv to the wall, we must have  added -mv to the contents of the box
Thus photons can impart momentum, so they must have momentum.

So... energy is being converted directly into momentum? Is that what you're saying basically?

[Halc]

Conservation of momentum says that if we have added mv to the wall, we must have  added -mv to the contents of the box
Thus photons can impart momentum, so they must have momentum.

So... energy is being converted directly into momentum? Is that what you're saying basically?

Well yes. I have chemical energy in me, and I can convert that to momentum by moving. This is probably not direct since several chemical reactions are involved, but the light example isn't direct either. Light has energy (and momentum), but light isn't energy (or momentum) itself.

In Alan's example, so long as the system remains closed, the total momentum is still zero (mv + -mv) so momentum is still conserved, but the momentum of the one wall (not a closed system) has definitely changed, and that was due only to the light applying a net force on it.

[alancalverd]

Not so much conversion of energy to momentum, which would offend three conservation principles, but the degradation of energy (increasing entropy) separating momentum vectors.

[Eternal Student]

Hi again.

I was also going to address this point:

Tons of people have come to give their answers to my past questions (my question about the true nature of energy is like 3 pages long with over 40 replies). I've also never seen a single person drop even a little bit of advertisement into their answer once, but maybe I didn't look hard enough for it at the time.

   This thread, I think is the one you refer to:    https://www.thenakedscientists.com/forum/index.php?topic=83150.0
It didn't have as many responses as you might have thought.  It's showing as two pages and if I counted correctly, only 8 people (plus yourself) commented on it.  Half of these people were moderators, so there were almost obliged to engage with people who post.

    I often look at the statistics on the main page when I first log on.  Quite often I'll be the only one loged on.

As regards advertising.  Here's some info from a moderator on another thread:

.....Then came the realisation that internet advertising was good, coupled with the development of bots and we started getting 200 spams a day - more than legitimate posts. Even now the main site can get over 500 a day and recently one of our mods took down 64.....

    Don't get me wrong.  I quite like this forum but it's worth recognising that it is actually a really small forum in comparison to many others.

Best Wishes.

[Aeris (OP)]

Quote Light has energy (and momentum), but light isn't energy (or momentum) itself.

Ok, so if light isn't energy or matter (I'm at least 99% confident in saying that light most definitely is not matter), what the hell is it then? 

[Aeris (OP)]

Hi again.

I was also going to address this point:

Tons of people have come to give their answers to my past questions (my question about the true nature of energy is like 3 pages long with over 40 replies). I've also never seen a single person drop even a little bit of advertisement into their answer once, but maybe I didn't look hard enough for it at the time.

   This thread, I think is the one you refer to:    https://www.thenakedscientists.com/forum/index.php?topic=83150.0
It didn't have as many responses as you might have thought.  It's showing as two pages and if I counted correctly, only 8 people (plus yourself) commented on it.  Half of these people were moderators, so there were almost obliged to engage with people who post.

    I often look at the statistics on the main page when I first log on.  Quite often I'll be the only one loged on.

As regards advertising.  Here's some info from a moderator on another thread:

.....Then came the realisation that internet advertising was good, coupled with the development of bots and we started getting 200 spams a day - more than legitimate posts. Even now the main site can get over 500 a day and recently one of our mods took down 64.....

    Don't get me wrong.  I quite like this forum but it's worth recognising that it is actually a really small forum in comparison to many others.

Best Wishes.

Meh. Still a more reliable site to learn about science than anything else on the Internet I've come across (not to mention way friendlier).

[Eternal Student]

Hi.

Ok, so if light isn't energy or matter (I'm at least 99% confident in saying that light most definitely is not matter), what the hell is it then? 

    At school level (let's say under 16 years of age).  Light is one form of energy.  That's it, full stop.  ....Well, almost, for some UK examination syllabuses  energy is NOT considered to have forms, there are just some stores of energy - but let's not worry too much about that for the moment.  If you said light was one form of energy you'd get that marked right most of the time.

    At University level, it's much harder to define what energy is.  I think you (Aeris) have started other threads about this.   Energy becomes a much more abstract quantity - just some number you can calculate and it stops being considered as any sort of substance or physical thing in it's own right.    With this idea, light isn't made of energy because energy just isn't any kind of physical substance.  Instead, light just carries some energy or has some energy value associated with it.

   So what is light at University level?  Well, it's interesting and I'm sure I don't have the definitive answer.
We want both of these things:
1.   It's something that exhibits both wave-like  and particle-like properties.
2.   On macroscopic scales, classical Electric and Magnetic fields seem to permeate all of space and light is a special type of oscillation or excitation in those fields.

   There is a model describing light as a classical electro-magnetic wave, which is true enough or good enough for most purposes at University.  It doesn't describe the particle-like behaviour all that well, we need some sort of qunatum model for that.

  And we often end-up with this conclusion:
3.   A quantum field theory seems the best model to explain what light is and how it behaves.  There is a fundamental field (which permeates all of space) for every particle in the standard model of particle physics.   So a photon is a quantised excitation of the underlying electromagnetic (or photon) field.
   I'm sorry, that probably doesn't help much.  It just says that fields may be the most (or the most so far) fundamental things in the universe and all particles are just excitiations in these fields.  This is unlikely to be the final story, it's just one of the best and most up-to-date that I'm aware of.  String theorists probably have their own opinions (which I know incredibly little about).

Best Wishes.

[Aeris (OP)]

Hi.

Ok, so if light isn't energy or matter (I'm at least 99% confident in saying that light most definitely is not matter), what the hell is it then? 

    At school level (let's say under 16 years of age).  Light is one form of energy.  That's it, full stop.  ....Well, almost, for some UK examination syllabuses  energy is NOT considered to have forms, there are just some stores of energy - but let's not worry too much about that for the moment.  If you said light was one form of energy you'd get that marked right most of the time.

    At University level, it's much harder to define what energy is.  I think you (Aeris) have started other threads about this.   Energy becomes a much more abstract quantity - just some number you can calculate and it stops being considered as any sort of substance or physical thing in it's own right.    With this idea, light isn't made of energy because energy just isn't any kind of physical substance.  Instead, light just carries some energy or has some energy value associated with it.

   So what is light at University level?  Well, it's interesting and I'm sure I don't have the definitive answer.
We want both of these things:
1.   It's something that exhibits both wave-like  and particle-like properties.
2.   On macroscopic scales, classical Electric and Magnetic fields seem to permeate all of space and light is a special type of oscillation or excitation in those fields.

   There is a model describing light as a classical electro-magnetic wave, which is true enough or good enough for most purposes at University.  It doesn't describe the particle-like behaviour all that well, we need some sort of qunatum model for that.

  And we often end-up with this conclusion:
3.   A quantum field theory seems the best model to explain what light is and how it behaves.  There is a fundamental field (which permeates all of space) for every particle in the standard model of particle physics.   So a photon is a quantised excitation of the underlying electromagnetic (or photon) field.
   I'm sorry, that probably doesn't help much.  It just says that fields may be the most (or the most so far) fundamental things in the universe and all particles are just excitiations in these fields.  This is unlikely to be the final story, it's just one of the best and most up-to-date that I'm aware of.  String theorists probably have their own opinions (which I know incredibly little about).

Best Wishes.

You know, it's funny. I LITERALLY just had an online chat with a cosmologist yesterday evening and one of the things he said to me was that matter, as we currently know it, may not actually exist at all. Fields exist, and particles such as Protons, Neutrons and Electrons are merely excitations of those fields (or something like that, I don't 100% remember what he said and my dumb ass was too lazy to write anything he said down). At any rate though, I do understand most of what you're saying. Mostly that we have very little idea what light actually is.