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As a general reminder, I think it is wise to remember that the concepts of ‘particle’ and ‘field’ are first and foremost mathematical models - to be precise, they are irreducible representations of symmetry groups. In physics, when we say that something ‘is’ a particle or field, then the verb ‘is’ should not be understood in a strictly ontological manner, but rather in the sense that these concepts are useful models for some observable aspect of reality. They are ways to make useful and functional models of the world, not irreducible ontologies. Consider the following effects: 1. The Unruh effect: for a given volume of space, the number of particles contained therein depends on the observer. An accelerated observer will figure that the volume contains more particles than does an inertial observer, even though they are looking at the same 3-volume. 2. The Aharonov-Bohm effect: there are measurable physical effects on charges due to an electromagnetic potential, even though the charges are located in a region where the electromagnetic field is absent (F=0). So clearly, our naive intuitions of what ‘particle’ and ‘field’ might mean can be very misleading. Ultimately, the question as to what exists in an irreducible way on the most fundamental level is very much open, in physics as well as philosophy. To me, it isn’t even clear what ‘exists’ and ‘most fundamental’ actually means, since these terms would need to be defined in a completely observer-independent way, which is difficult to say the least. Modern physics takes quantum fields and spacetime to be the most fundamental categories of (physical) existence that we know of, but there is certainly no claim that there couldn’t be something else that is even more fundamental - in fact, it is quite safe to claim that there most likely will be. There are also other ways to make models of what we already know - Rovelli’s relational QM, where the central category is a network of interactions rather than a collection of entities with given properties, is a good example. With all that being said, particles and fields are far to useful as computational models in order to simply abandon them.

In quantum field theory, particles are characterised as irreducible representations of symmetry groups. Symmetry transformations are different ways to look at particles that leave the quantum state unchanged. When these transformations can be expressed in terms of a finite number of parameters, these groups of transformations help us classify the particles according to their so-called Noether charges. When the system is symmetric under one of these groups --also called Lie groups--, Noether's theorem guarantees that these "charges" are conserved. Some transformations have to do with space-time symmetries. Examples are translations and rotations, which have the corresponding conserved quantities that we're familiar with under the name of linear momentum and angular momentum. In any quantum theory, charged particles are represented by complex wave functions. Everything observable depends on quadratic expressions of the form (field)*(field), where the asterisk represents complex conjugate. Because the physics is indifferent to a global phase change, a conserved quantity exists --by virtue of Noether's theorem-- that we call electric charge. In the case of angular momentum --due to symmetries under rotations--, it so happens that the spatial coordinates are not enough to represent all the rotational states of particles. Internal variables must be specified describing the orientation of a particle that allow no representation in terms of spatial coordinates. That's what we call spin. Spin has to do with rotation, although it's not nearly as intuitive as the rotation of a spinning top, eg. Charge has to do with something even more abstract, which is a phase shift in the wave function. This transformation is sometimes called "internal." Isospin invariance is not exact, it's only approximately conserved. It is an analogue of electric charge, and also occurs in this "internal space" of elementary particles. It so happens that, if you ignore electromagnetic interaction, a proton and a neutron are very similar when you only consider the strong nuclear force. You can kind of rotate the states smoothly from "being a proton" to "being a neutron." This is in close analogy with electric charge. There are other analogues of electric charge: baryon number, lepton number, hypercharge... Colour charge is similar, but more complicated, as the previous charges depend on a 1-parameter group called U(1), while colour is defined in terms of a 3-parameter group SU(3). Mass is very different. It is not a conserved quantum number like the other charges. So I would say that what gives a particle its charge and spin are its properties under global gauge transformations (global phase shifts), in the case of charge; and rotational properties, in the case of spin. This is a summary of the present theoretical understanding of these things within the context of the standard model of particle physics.

Nobody is mad at you, we are just trying to guide your thinking so you can see for yourself. 1) Black body radiation. I stick a poker in the fire and it glows red, then yellow, then white. I don't see any quantum interactions here and you have specifically limited this discussion to quantum matters. 1) Photoelectric effect Here there is an interaction because an electric current is produced when a light shines on certain materials. But there is nothing that suggests light needs to be a Field. Swansont mentioned one of the characteristics of this effect that lead to the conclusion that this must be a quantum effect since classical EM wave thoery will not produce this effect, but a different one that is not observed in practice. Read the attachment I previously posted before you reply. I don't think I have posted this analogy since you have joined but maybe it will help a bit. Think of a stream bed with an smooth clay or sandy bottom. The stream flows in steady parallel lines with no disturbances. This is an example of a Field, called a flow field. Now change the bed to a rocky bottom. The flow changes and eddies appear around some of the rocks. A few of these eddies are transient but many are persistent. These all constitutes a disturbance in the field and involve greater energy due to the rotation of the fluid field at the eddy location. Noone pretends that the eddies are points, they occupy real volume. So within the field there can bee seen persistent disturbances, of higher energy than the surrounding general field. These disturbances can be regarded as self contained entities, and if they relocate they move as self contained entities ie they have particle like characteristics This is a very simple picture of the proposition 'a particle is a disturbance in a field'. Does this help ?

Because the Van de Graaff generator is right now in my rest room.. ? (no joke, really)

It seems you've come up with a foolproof way to prevent these types of viruses from occurring naturally. Simply build labs next to every wet market.

I'm assuming you mean the energy of N photons, where hf < 1eV and Nhf = 2eV? I was saying earlier, there would have to be a localized form of energy that mediates interactions, so fields wouldn't interact with each other directly. hf would have to be the quantization of interactions between the EM field and the intermediary. Please don't be mad at me. I know this all probably sounds hokey and ignorant, but I'm really not trolling. I just don't like a lot of things in modern physics, and I'm trying to make sense of them as well as I can.

I must say it has always seemed to me that the notion of "particles" is a fairly preposterous construct, when one thinks about it: the idea of an entity with no physical dimensions but nevertheless finite properties such as mass, charge, intrinsic angular momentum etc. Just as artificial as "waves", really. Originally, in classical physics, the concept of particles was merely used to simply physics problems to their essentials, for ease of modelling. Like you, it has often seemed to me that QM entities only behave like particles when they interact. Reading Rovelli's Helgoland last year, I was quite impressed by his idea that QM entities only have defined properties at all when they interact, so we should perhaps let go our idea that they possess them in a continuous sense in between.

I'm in. One of the funniest films ever! The planet porno attacks the earth with the super sex beam!

The Thirteenth Floor is a special favourite - as noted by TheVat it was based on a German TV series called World on A Wire. If you enjoy VR based SciFi theme films, then you might also enjoy Avalon (2001) which is Japanese/Polish collaboration directed by Marmoru Oshii - who is probably better known for his original animated version of Ghost in The Shell (1995). Avalon was made on location in Poland with a Polish speaking cast and crew. A stand alone sequel called Asssault Girls set in the same world was released in 2009

Flesh Gordon (1974)

I suspect they're far more useful to adults refreshing their knowledge or broadening their education than for full-time students. Motivated mature learners have a much longer attention span.

When news came out of this rocket hitting Poland, I immediately thought it was heavily odds-on the Zelensky had fired it, in a crude attempt to get Russia blamed, and drag NATO into a shooting match. Everything that's emerged since has fallen in line with that scenario. Zelensky probably calculated that he could aim it at the countryside, away from habitation, and everybody would go along with the deception and not look too hard at the details. What went wrong was that Polish People died, so the Poles were angry and not at all inclined to go along with it. So it was properly investigated and the source was established as Ukrainian. What's telling is that not one media source (that I've seen) has even raised the possibility that it was a deliberate act by Ukrain. Just show that our media are into propeganda, not news. But NATO probably knows, and are keeping their mouths shut.