Entities and attributes in science

arfa brane:

You just spent a lot of time complaining because people who you consider "authorities" apparently have a different opinion about energy than I do. As if science is decided by authority.

What you didn't do - and this is a notable in its continual absence from your posts - is to make any attempt to refute the argument that I put to you. You know, on the basis of rational reasoning, logical arguments - that sort of thing. That's what good science is based on, not what some "authority" or idol figure says.

And I told you that anybody who claims that photons are a "form of energy" is wrong. I explained why.

See if you can refute the reasons I gave you, rather than just complaining that my argument doesn't match what your googled sources (wrongly) claim. Try to make an argument of your own, rather than one based on presumed authority figures. Try to think for yourself.

Yes.

You have made no attempt at all to give any coherent reason for why the NASA source (probably a publicist) or the university (who knows?) would be right about this.

Please try your best to do that.

Your argument from ignorance is a logical fallacy.

No. It's more that a lot of people are sloppy about this sort of thing, so they often get it wrong. Moreover, a lot of people simply haven't thought it through. And/or they were poorly taught.

Maybe, but at least I've given reasons I hold the position I hold. Your only reasons, so far, seem to be (a) authority based and (b) a result of a complete failure to seriously consider what I have put to you.

I don't care about your "authorities". Tell me why I'm wrong. Make a logical, reasoned argument for your position. If you can.

Of course. People define all words as they see fit.

What's the "well-defined" meaning of "physical", according to you?

If a rock physical?
Is Planck's constant physical?
Is the theory of relativity physical?
Is the fossil record physical?
Is "1 kilogram" physical?

Or physics struggles with philosophy a lot. Or, they are two separate areas of inquiry, with some areas of overlap. Or something.

Take your useless ad hominems elsewhere. I'm not interested in that personal bullshit, especially from you. Grow up.

Yes. Some kind. Now, brain on. Think about what I have put to you. Try to formulate an actual argument against it. Stop whining.

This is rich, coming from you. Try turning that mirror around. Take a good long look at yourself.

With all due respect, you seem quite unqualified to judge that accurately.

You just told me that, in science, words are preferred that have well-defined meanings.

So, tell me: what are the well-defined meanings of "attribute" and "physical", in science?

Support your claims.

Heat is a number. It doesn't cause anything to do anything.

That's one reason you're so confused, no doubt.

It would be best if students were given the correct notion of what energy is early on in any physics or engineering course. Unfortunately, many standard texts fail to communicate this. It is just sort of assumed that students will somehow work it out for themselves.

When people fail to understand energy from the start, they can go through the whole rest of a degree in physics or engineering (or chemistry or other sciences) with a fundamental misconception about what energy is. They can then, potentially, go on to have careers, taking their misconceptions with them. Then, years later, they end up where you are, with these vague, incorrect notions about energy.

The causation in that sentence does not follow, but you have bigger problems than this so I'll ignore it for now.

I accept that momentum is "physically real", using the definition you provided previously: it has units, so it is "physically real". Satisfied? I can't see any need to go beyond your blinkered definition on this point, for now.

What do you mean by "transfer", here? What is being "transferred"? Can you put it in a bottle?

Whatever it is that photons do, electrons do something similar, when it comes to momentum. They are both, after all, entities, as I have defined that term.

i.e. momentum is an attribute of a particle. Yes.

... a particle hit the screen.

 

arfa brane:

It's a common mistake to claim "electromagnetic radiation is energy". It's even written into some textbooks, whose authors should have known better.

Waves are one model of light. A different model is a particle model. Yet a different model is a quantum model, that combined properties of waves and particles. This should give you a hint that a model of a thing is not the thing.

i.e. you have a mathematical description of something. Then you apply some maths to derive a numerical quantity of that mathematical something. Okay. So what?

I did not say this doesn't apply to waves. Don't put words in my mouth. I forgive you, because - as you say - you don't get any of this. You're a little lost lamb in these woods. It's not suprising you're simply compounding your initial errors.

See, the thing is: to understand something requires that you put in some effort. Maybe you should try it.

Is that a model, or something "physically real"?

Sounds reasonable. Although a vacuum is more of an absence of a thing, rather than a thing. Perhaps you should start with something simpler - like a rock. See if you can work out whether a rock could be put in a bottle. If it could, it might be an entity. If not, it could be an attribute, or something else (like a concept). Try. Think.

 

billvon:

No. EM radiation is a form of radiation, not a form of energy. Radiation is not energy. Photons are not energy. Light waves are not energy.

Did you read what I wrote about transfers and "conversions" of energy from one type to another? It's only a few posts above, in this thread.

Why are you repeating a point that I already addressed in detail?

Never converted to something that isn't also a number.

Essentially, you are claiming that because 1000 = 200 + 800, there are "two new types of number" when we split the number 1000 into amounts of 200 and 800.

 

Moderator note: arfa brane has been warned for insulting another member.

Due to accumulated warning points, arfa will again be taking some time out to reconsider his behaviour towards other forum members.

 

arfa brane:

They are all wrong, for reasons I explained.

Instead of trying to formulate a rational argument, you decided to try another ad hominem attack. Please realise that personal attacks are not a subsitute for a reasoned reply. Please try to do better, like I asked you to try in my previous post to you.

Yes, and I explained why.

It's no wonder you're struggling, if you used bad textbooks.

And there it is, again. Lacking any substantive rebuttal of what I have told you, you revert to type and act like a child in a playground, insulting the other kids.

Will you ever grow up? How old are you? I have always assumed you are an adult, at the very least.

Wrong. Heat is a form of energy, and energy is just a number. Therefore ... think about what follows.

The sun feels hot because if you stand in the sun you absorb a whole bunch of photons of light, which cause atoms in your skin to vibrate faster, which then bang into other nearby atoms, eventually distributing this atomic motion throughout your body. You feel the sensation of warmth because of various biological structures in your body - namely your nervous system and your brain, which together react to stimuli of various types, caused not by "energy" but by physical interactions with physical entities.

Don't be silly. Philosophy hasn't failed. Besides, your misconception about energy is fundamentally not just a philosophical misconception, but one about basic physics.

You have yet to even start attempting a rebuttal of any of the substantive claims I have made. All you have managed to produce in response so far are childish insults and exclamations of your disbelief.

Nothing in this impacts on the arguments which I have put to you.

Try to do better. Or keep ranting like an angry child who is upset to discover that he has been wrong about something. Your choice.

 

billvon:

I explained why it is a mistake to make that claim.

How do you respond to the argument I put to you? Where's the flaw in my argument?

"Carries" in a literal sense, or a metaphorical one? The difference is important.

The fact that we can associate a particular number with a particular photon and call that number "the energy of the photon" doesn't imply that the photon is literally carrying the number. More specifically, the photon is not carrying any substance that can be identified as "the energy".

There's no such thing as a bottle full of energy.

Do you understand the argument? Do you agree?

 

billvon:

You're saying that photons carry something that is "immaterial"? What does that mean, exactly?

How can something immaterial be carried?

How can you tell the immaterial thing is really there (in the photon or atom or whatever), if it's immaterial?

Do you agree that there's no way to directly detect this energy that you say is "carried" by things? You can't, for example, build an "energy detector".

Do you? How can you tell the space is full of energy? What did you do to view the energy?

Can you put some energy in a bottle by itself (that's the test I proposed, remember), and look at it or detect it in some way? If so, how?

 

billvon:

Is energy the only immaterial thing that can be "carried" by photons or other particles, or are there lots of immaterial things that are carried around? Can other immaterial substances be detected using material equipment, or is energy the only one?

That's a claim. It says that energy is separate, in some sense, from the laser beam, but the energy comes along for the ride when you have a laser beam, for some reason.

That's a different claim. It says that the laser beam and energy are indistinguishable from one another. This immediately invites the question as to why we would need two words for the one thing. It also raises questions about other "forms of energy", many of which do not seem to be laser beams.

Which claim do you want to make? Claim #1, or claim #2? That's the first thing you need to work out.

You're saying that the fact that photons (or atoms, say) move from place to place is evidence that they "carry" energy? (claim #1, above)

My argument is: energy is a concept we use to describe a certain aspect of something "moving from place to place".

If your claim is claim #2 (photons actually are energy), that seems quite bizarre to me. Why two different words for the one thing?

But you seem to be saying two different things:
(1) Photons carry energy.
(2) Photons (electromagnetic radiation) are energy.

Which is it? You started with (2). Now you seem to have moved to (1). Do you want to walk back your previous claim (#2), then? Do you now agree with me that photons are not energy?

Your argument is that you can tell that an immaterial thing is really there by observing its effects.

What effects does energy have?

Suppose you shine some light on your skin (using a heat lamp, say) and your skin warms up. Was it the photons landing on your skin that made your skin warm up, or was it the energy "carried" by the photons? (Or do you want to persist with the claim that there's no difference between photons and energy?)

Would you say that photons are "immaterial"? Or are they "material"? If photons are energy, as you previously claimed, that would make them "immaterial", because you have said that energy is immaterial. On the other hand, maybe the photons are "material" and they merely "carry" this immaterial energy thing.

What makes you confident that it is the immaterial thing (the energy) that warms your skin, rather than the material thing (the photons)?

Not "contain". It is you who claims that "a mass" "contains" or "carries" kinetic energy.

My claim is that we can associate a number - a concept - with the motion of a material entity (an atom, say, or a tennis ball), and call that "the kinetic energy" of the entity. I disagree that this implies in any way that there is an immaterial substance called "kinetic energy" which can be carried around by physical (material) entities. The immaterial substance idea is your claim, not mine.

Are you asking how I can tell if something like a tennis ball is really there? Well, I can touch it, for example. I can feel it. I can pick it up and throw it. I can put it in a bottle. Energy? Not so much.

You've built instruments that detect energy?

Are you sure they aren't detecting photons, for example? Or some other material effect?

You can measure the energy of space directly? How?

Photocells work by absorbing photons, don't they? They require photons to operate. They do not detect energy. How could they? You said energy is immaterial. Wouldn't some interaction between a photocell and the thing it is detecting be necessary for the detection to work? How can an immaterial thing interact with a physical (material) detector?

A little context: physicists recognise only four "fundamental" interactions in nature: electromagnetism, the strong interaction, the weak interaction and gravity. These interactions "work" on the basis of physical particles - photons, gluons/pions, W and Z bosons and gravitons (this last is yet to be confirmed, of course). There is no "energy interaction". There are no "energy particles". Why? Because energy is "immaterial", like you said.

Given this, I don't understand why you claim that "energy" can cause physical changes in something material. What would the mechanism be, for the immaterial energy to do anything? Compare my position on this: I say that energy can be used to describe certain aspects of interactions, but the interactions themselves involve those particles I just mentioned - i.e. physical (material) things, not immaterial abstractions.

I say that photocells detect light (photons), not energy.

As far as I can tell, you only have two ways to dispute this (if you want to do that):
(1) claim that photocells don't require photons to operate - (energy alone will be sufficient for it to work); or
(2) claim that light and energy are the same thing;

You started with (2). But if (2) is true, then it makes no sense to claim that "photons carry energy"; just say "photons are energy" and be done with it. There's no need to introduce a fiction that one thing can be divorced from the other, if your position is that the two things are identical.

But if light is energy, then what about something like the kinetic energy of a tennis ball? For consistency with (2), you're then going to have to say that tennis balls somehow carry photons.

I hope you can see that (2) is untenable. Which leaves you with the strange claim #1.

Claim (1) leaves you on very shaky ground, indeed, because I think you'll find that in every single instance in which a photocell "detects energy", light (photons) of some kind is also present. Hence, it seems reasonable to consider the idea what what the photocell is really detecting is the light, not the (immaterial) energy.

Perhaps, if you drop claim #2, you will try to fall back (as you already seem to have done) that photons carry the immaterial energy. In that case, the defining experiment that will prove your claim is when you manage to use your photocell to detect some energy without any photons present. Obviously, if you can achieve that, then the claim that photocells detect photons rather than energy will be dead in the water.

How do you rate your prospects of proving that photocells detect energy rather than photons?

Going beyond this particular example, are you aware of any detector that detects energy by itself, without some kind of particle being involved? More generally, how could any immaterial thing influence the behaviour of any material thing; what's your theory of how this could work?

If you can't isolate the immaterial energy from material particles, the questions becomes: what makes you think the immaterial energy is "real", in the sense of being like a substance that can be "carried" by particles? Aren't you just detecting particle behaviours, in the end, and then attributing those behaviours to this fictional immaterial substance you call energy?

 

billvon:

No. The "energy of light" is just one aspect of a full description of the light.

Suppose you write down everything there is to know about the energy of a laser beam. After that, you will still not have completely described the laser beam. Most fundamentally, what is the beam "made of"?

It sounds like you think a laser beam is "made of energy". That's a fundamental category error. Energy is not a substance. Nothing can be "made of energy".

In fact, a laser beam is "made of" light. Light is not energy. You have already admitted that energy is not the same as an electromagnetic wave or a photon. Therefore, light is not a synonym for energy; nor is energy a synonym for light.

I asked you about "forms of" energy previously, but you have done very little to address what I put to you in that regard.

You're still vacillating between "light is energy" and "light carries energy". Which do you think it is? They can't both be right. In fact, neither of them is right, but if can at least sort out this distinction in your mind, we only need to kill one bird rather than two.

Properly speaking, EM waves and photons are models of light. That is, they are concepts or theories used to describe and predict how light is observed to behave.

You seem to be part of the way there when you use the word "representation". A representation of a thing is not the thing. The map is not the territory. You do agree with this, don't you? It follows that neither photons nor EM waves are "light energy", if they are merely "representations" of light energy.

Of course, my argument is that photons and EM waves are not representations of energy at all; they are representations of light.

I'm not sure how your analogy is supposed to apply to light and energy. Is energy the river? Or is light the river? What is the analogue of the water - the light? the energy? space?

(Also bear in mind that light requires no medium to propagate in. Although, having said that, I think this whole analogy is unhelpful in getting to the nub of your misconception here.)

If you think that light is a "form of energy", doesn't it strike you as at all strange that so many other "forms of energy" seem so radically different from light? Consider, for instance, nuclear binding energy. Or gravitational potential energy. Or just plain old kinetic energy. None of these things I've just mentioned seem to fit easily into your river/water analogy, which suggests to me that it's not terribly useful if you're thinking about energy.

I was specifically drawing your attention to the words "light" and "energy", but this is covered sufficiently above.

My definition of "entity" in this thread has been "something you can isolate in a bottle (of some kind) by itself and detect its presence in some way". Are you happy to work with that definition, or are you using your own definition of "entity"?

Do you think you can put energy in a bottle by itself and detect its presence? Note, for example, that putting some light in a bottle with mirrored walls won't do the trick, because in that case light is in the bottle, not just energy. Now, this objection would go away if it were to turn out that, as you claim, light is energy. But I am hoping I can talk you out of that misconception.

You comment energy "does not have mass". I'd rather not dig into that yet, because it's one layer down from the first distinction I want to make first up: the one between light and energy. I agree that photons have no rest mass, of course. But it does not follow that therefore photons must be energy.

Focussing on what energy is, then ... Does the "non-material" nature of energy strike you as at all problematic?

Previously, I asked you if it was possible to directly detect energy. You claimed that you could build an "energy detector". You have not responded to what I wrote to you about photocells. How do you respond to that? Do you still think you can detect energy, even though it is "non-material"?

Consider gravitational potential energy, to take another "form of energy". Can you build a gravitational energy detector, do you think? And while we're at it, where are we to find the gravitational potential energy, exactly? Where, spatially, is it located? Consider, for instance, the gravitational potential energy of the Earth and Moon. Where is it, exactly? Can it be detected?

You're still flip-flopping between "energy is carried by things" and "energy is a non-material entity". Which is it? (Hint: it is neither.)