What is Energy Really?

OK, don't lump me in with the "Intelligent Design" group, who I really think misappropriate those terms for their own purpose in the same way that Homosexuals misappropriate the word "gay", with the result now that a perfectly good word is anathema to its proper use, and make old texts, films, songs, poetry, and recordings which use it in the proper manner a source of gigglosity (my word) for the younger generation(s).

I think if you read my last response to Dr.Moose (#112) you will understand that though we share a common religious belief our approach to the divine text and to the scientific record is far different.

In seeking a clarification of your terms, which seemed a bit contradictory, I hope I was practicing a good scientific approach, and I thank you for you amplifying remarks and I couldn't agree more with your second paragraph, as you might see in my other posting. It is exactly this absence of (scientific) evidence that makes faith so important. For Christians, we have the evidence of Jesus' unquestioned historically true existence, and the testimony of eye-witnesses as relayed through his faithful disciples until the accounts could be safely written and conserved in documentary form (early Christians being persecuted, tortured, and executed in the Roman Empire before it embraced Christianity made any such documentation highly dangerous).

Cheers!

Long ago, I had an instructor/mentor who told me that the statement "I do not know" was the beginning of all knowledge and all wisdom. To my knowledge, this has never been proven false.

In my high school sophomore Honors History class I had a teacher who taught us that if we were good students we would always be a "sophomore" and there was nothing wrong with being one. This puzzled us since "sophomoric" is often a derisive term, meaning literally, partly wise and partly foolish. He explained that as long as you KNOW that you are a "sophomore" and only have gained partial wisdom and knowledge, you would continue your quest to learn. Only those who think they are all wise and all knowledgeble are truly foolish!

Lesson learned. Thank you, Mr. Klein, wherever you are!

Here's an interesting note: they now know the type of energy that was first present during the first seconds of the "Big Bang". they now know that the four elements were all present in that pea size "matter ball"!

It seems to me that both energy and mass can be defined as a means of comparative measure between phenomena encountered in the universe. Someone once said, "An event is a very short-lived object, and an object is a boring event". If one has only a single phenomenon, one can speak neither of it's mass nor it's energy, nor how long it has been around. If one adds an observer that has the ability to distinguish between self and the observed phenomenon, then the observer can say that the object moves toward or away from self, that the object is bigger or smaller than self. If one adds another phenomenon to the mix, then we can get in to some serious measurements...

What is Energy Really,

I do not have the education level that many of you seem to have, I do not even have a four year degree.

I do have 30 years working within the electronic industry, isolating and resolving faults, and today I cannot even obtain a job.

However, my youngest son asked me this same question and when I tried to comprise a simplistic response, being I normally look at it via means of electron movement, he came back with, energy is the act of, "CHANGE".

Looking into it, just a little prior to me scripting this response, I have come to an understanding that for the most part CHANGE is ENERGY.

As for humankind and energy, it seems if it can be measured, it can be explained, reproduced "under a controlled environment" and used to make money many will get the opportunity to experience it.

Now if it is a change that mankind cannot explain but can generate a need of understanding many will remain confused but again money will be made.

In the end, CHANGE is the effect of ENERGY.

CHANGE OR DIE Really!

Good post , Carl.l.Greg. Movement =energy. But adding the human equation is a meaningless action! I mean compared to the Magnitude of the Universe!

Hi, carl.l.gregg!

--re your post 'energy is the act of, "CHANGE"'--

Energy is neither an act nor an action.

Measurements in quantifiable units reflect changes.

The action of 'change' merely provides an observable difference.

Your youngest son's obvious ability to reason in an independent fashion makes him sound like a real "keeper", to me; and I share your pride in him.

But he has made a quantum (or maybe even a fairly large) leap into conclusion based upon only observation, and added a non sequiter. "A thing has changed. Therefore energy is being displayed." He could have proceeded with smaller, verifiable conclusions before labelling change "energy".

Mark

PS. Electrician's helpers are often employed to trace circuitry so as to locate breaks, ground faults, etc. They make a good buck.

So do self-employed person who advertise to find such things for ordinary folks: "Electrical Problems? Have your electrical circuits traced to find line breaks and ground faults by an experience electroncis expert. Call Carl at _________."

It'll cost you ^+/-$100 bucks to place the ad in a community newspaper group (not a regular tabloid...too expensive). Charge $50.00 an hour --or part thereof--and give callers an advanced free estimate of how much time you think it might take.

Mark

Sorry, However I must give my opinion # 1 million!

Energy! Ok, the first thing that comes to mind is LIFE!

energy=is what makes up everything, period!

We ""munipulate"" energy to do many things! BUT* you nor I can change energy!

We all "think" we do but in reality NO we cannot !

We as a civilization here on earth have made-up many clasifictions to many unknowns that we have come some-what familiar with but still do not understand, we just be-leave or (Be present learn / leave 2-make $ to live / survive) !

Energy is just a word "as is everything we write" that someone made-up-somewhere? on earth we all think so but could it be that words came from somewhere besides Earth?

Don't misread many words are made-up here on Earth!

Trivia to you the reader! find who made the 1st word up??????????

However Energy is not a state nor a thing; it just is always present!

So energy=God?

Genesis 1:1-2. "In the beginning, God created the heavens and the earth, and the earth was void, and formless, and the spirit of God moved upon the face of the deep. And God said, 'Let there be Light!', and there was light." Sounds as good as anything else I've heard. So yes, indeed, God may be thought of as the source of all energy, including that essential energy that kicked everything off. Makes sense to me. Funny how much sense this stuff can make from the right point of view.

Works for me.

Interesting about that "Let there be light" bit, considering what our current theories describe as the conditions of the early Universe: the first moments of the Big Bang (after symmetry breaking) supported nothing else. Light, and lots of it. And for quite some time afterward.

The amazing thing to me about "Let there be light" as the first step is that some old "misguided coot" (to many) wrote this incredible piece nearly three millenia ago. Think about "Let there be light" in terms of the concept itself given the history, the level of scientific development (practically none) and the culture of the times. Even if this were knowingly intended as a mythological bit of fiction in a greater fictional Creation Mythology, it is amazingly inventive even so. More importantly, this Mythology departs in radical ways from all other extant creation mythologies of the times including (and especially) those of the Egyptian and Chaldean cultures with whom Israel had the most contact.

I do not find myself nor thrive in the fields of God! If there is one it would be me

However, theories are descriptions of thought, correct?

So I gave my thought on the matter butt energy is "NOT GOD"

Energy is life as you, I, and everyone else knows it to be no matter what they beleive about God!

Opinion:

The GOD theory is for weak minds who need an excuse in life!

""""""""And to add I don't beleive in the Devil either so if you want to say I am evil cause you are a GOD THEORIST then go ahead and do so as if it will make anything better! """"""""""""""

Good Day!

The GOD theory is for weak minds who need an excuse in life!

Oh, really? Albert Einstein was a believer in the "God theory", so I guess he was one of those "weak minds who need an excuse in life". So was Newton, Galileo, Ben Franklin, and most of the top scientific minds of the last millennia.

Perhaps Atheism and Agnosticism are for weak souls who are afraid to acknowledge that there is a higher power at work in the Universe than themselves. I am sure that the most evil people in history must have been either completely insane, or so sure of their own supremacy, that they had no fear of answering to another for their crimes.

To paraphrase Shakespeare: Methinks thou "doth protest too much"!

Perhaps Atheism and Agnosticism are for weak souls who are afraid to acknowledge that there is a higher power at work in the Universe than themselves.

I agree that atheism indicates a "weak mind" (more specifically weak logic) since atheists accept/assume a proposition (that God definitely does not exist) as true despite the lack of empirical evidence. Since empirical logic cannot absolutely proves the non-existence of a thing, atheists will never have definitive evidence to support their claim. In other words, just as religionists do, atheists rely completely on faith! (they become livid when I point this out). Agnosticism on the other hand indicates an honest open mind -- I don't see anything weak about that. If God (whichever version you choose) does exist, I will gladly affirm this when I see convincing evidence. Until then I humbly admit that I don't know for sure, but I don't rule it out either.

"...atheists accept/assume a proposition (that God definitely does not exist) as true despite the lack of empirical evidence. Since empirical logic cannot absolutely proves the non-existence of a thing, atheists will never have definitive evidence to support their claim. In other words, just as religionists do, atheists rely completely on faith! (they become livid when I point this out). Agnosticism on the other hand indicates an honest open mind..."

Bravo! Well put!

Svengali writes: "I will gladly affirm this when I see convincing evidence."

-----

Hi Svengali,

What evidence would you consider to be convincing? What would you have to see/experience/whatever to become convinced (either way)?

Cheers

To feel certain about the existence of God, I would need to see God in person. Even then, I would need some serious convincing that I had not fallen for a hoax perpetrated by powerful extraterrestrials. Also I would need reassurance that I did not hallucinate the experience (even though I don't use psychoactive drugs).

As for the opposite conclusion -- that God does not exist -- I could never come to such a conclusion for the reasons I already gave (i.e., atheism relies on pure faith). So I see only two logical options: either agnosticism (in the absence of empirical proof) or theism (after seeing credible empirical proof).

No big feat. Atheists see him every time they look in a mirror. The whole point of atheism, really.

Well put e! Bravo to you.

Hmmm, it seems to me that all three groups are Believers. Here is what they believe:

Religionists/Theists: I believe God exists. I don't need any evidence for myself, but it is nice to have some to help convince others.

Atheists: I believe God does not exist, and any evidence presented to the contrary of that must be false, contrived, or some other kind of trick.

Agnostics: I believe I don't know if God exists or not, but I am willing to believe if I am presented with incontrovertible evidence that can be proven not to be false, contrived or some other kind of trick.

So, in other words, an Agnostic is just an Atheist who has doubts about the non-existence of God.

The funny thing is, many, if not most Religionists/Theists also harbor some doubt precisely because we are imperfect beings and that is what is called "Making the leap of faith". Committing to a Belief does not necessarily mean that all of your doubts automatically vanish. It means that you are willing to overlook those small doubts that otherwise would be an impediment to your faith.

Sounds to me like an Agnostic would really like to be an Atheist, but those doubts about the non-existence of God are the impediment to becoming a true believer in Atheism. Rather than sitting on the fence, and willing to go either way as you would have us believe, you put the burden of evidence upon the Theist side, saying, well, I am not going to Believe in God until you PROVE he exists, and telling the Atheists, well, I really don't believe in God either, but I just don't know for sure he doesn't exist, but I am not asking you to prove he doesn't exist either.

Did I get that right? Not quite as self-serving description as the way you put it, but I think it draws the same conclusion.

So, in other words, an Agnostic is just an Atheist who has doubts about the non-existence of God.

Quit playing with semantics. Theists and atheists have very definite beliefs pro or con. An agnostic simply admits "I don't know". Most people want others to take definite black-and-white all-or-nothing positions on important issues. They feel uncomfortable with uncertainty and open-ended questions. But sometimes wisdom dictates that we keep an open mind until we have more information to go on.

"The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts." -- Earl Bertrand Russell

Perhaps Atheism and Agnosticism are for weak souls who are afraid to acknowledge that there is a higher power at work in the Universe than themselves

By the way, I think most atheists and agnostics would readily admit the existence of a greater power than themselves: a vast mysterious complicated possibly self-aware entity -- the universe itself.

By the way, I think most atheists and agnostics would readily admit the existence of a greater power than themselves: a vast mysterious complicated possibly self-aware entity -- the universe itself.

Well now, in light of your other posts, and in contradiction to the apparent belief of many Atheists, that they see God as themselves, there being no higher (spiritual) authority, I would say that your statement above is just a cop-out!

OK, don't call it a cop-out, call it a Cosmic Disclaimer! If you "would readily admit the existence of a greater power" than yourself, which "is a vast mysterious complicated possibly self-aware entity", which you call "the universe itself", what is the difference between that and calling it "God" or any other name, Allah, Yah-weh, etc., other than now that implies a personality and ability to take thoughtful action, and not just pre-programmed reaction, to events and actions of others. I think the hang-up is on the word "possibly" and I would submit that for an Atheist, this is NOT possible, while the "possibility" of such an omnipotent, omnipresent self-aware entity, essentially a Supreme Being, is what make you an Agnostic. Therefore, there is a vast difference between the two.

There might be hope for you yet! <grin>

thanks johnjohn,

i always wondered what kind of agnostic i was. now i still don't know. it is hard for me to choose between Militant agnosticism, apathetic agnosticism, agnostic atheism, ignosticism. i can relate to all of them. is there one that combines these four? i guess that i actually move from one position to another, of these, based upon who is trying to convince me that i am wrong.

"is there one that combines these four?"

"Synergistic agnostic", perhaps?

"i guess that i actually move from one position to another, of these, based upon who is trying to convince me that i am wrong."

Then maybe, "Metastable agnostic" would be more appropriate!

ROFL

the apparent belief of many Atheists, that they see God as themselves, there being no higher (spiritual) authority, I would say that your statement above is just a cop-out!

To whom is this belief apparent? To you and europium? I didn't know that you spoke for atheists. Atheists generally don't consider themselves gods, at least not any that I have encountered (can you point to any documented examples?) They simply don't believe in gods at all.

What I wrote does not qualify as a cop-out. I stated that a power greater than humankind *might* exist. And I did not equate that power with God -- it might have a status greater than human but *less than God* (you must admit that there exists a chasm between these two extremes). So I did not contradict my agnosticism.

OK, don't call it a cop-out, call it a Cosmic Disclaimer!

No, not even a disclaimer. You misunderstand what I wrote.

If you "would readily admit the existence of a greater power" than yourself, which "is a vast mysterious complicated possibly self-aware entity", which you call "the universe itself", what is the difference between that and calling it "God" or any other name, Allah, Yah-weh, etc., other than now that implies a personality and ability to take thoughtful action, and not just pre-programmed reaction, to events and actions of others.

Well gee, other than the tiny difference between "a personality and ability to take thoughtful action" and "pre-programmed reaction" I guess the ideas of universe and God don't differ at all!

I think the hang-up is on the word "possibly" and I would submit that for an Atheist, this is NOT possible, while the "possibility" of such an omnipotent, omnipresent self-aware entity, essentially a Supreme Being, is what make you an Agnostic. Therefore, there is a vast difference between the two.

Yes, contrary to what many theists would have us believe, atheists and agnostics do have very different attitudes. Thank you for noticing this. I grow tired of refuting the ignorant claim that "an agnostic is just an atheist that is afraid to admit so". Really, I hope for (and admit the possibility of) the existence of a benevolent intelligent higher power that cares about us. We could certainly use some help. But because my definition of the word "know" depends on empirical knowledge, I don't *know* whether such a being exits or not.

We put God in tiny little box and make demands that He be like us. To be as we expect. As if we were really something.

I agreed with everything you said until the very last sentence:

"As if we were really something."

But we ARE something. We are His creation, made in His image (although it might be a Fun House mirror image, fuzzy and distorted, possibly even inverted, like the ones described on another thread!). And we are his beloved creation, as imperfect as we are. Your analogy with the potter and the clay was very good. The potter loves his creations, and he makes a space for them among his other treasures. He loves to talk about them to his family, "Here's one, little Europium. He's a little cracked, a little shopworn around the edges, but once you get past that you see he is really a thing of beauty, a vessel to be filled with knowledge that he can dispense to others. I just love him, despite his flaws, and I think he is perfect! Why? Because I made him of course!"

The part I don't understand: if God loves us so much, why would He (in the afterlife) inflict *infinite* punishment on anyone? Thats sound extremely sadistic. Seems like the punishment should fit the crime, which would mean a *finite* punishment (if we are made in God's image, then He should have a reasonable sense of fairness). Re-incarnation makes much more sense -- suffer in direct proportion to one's crimes, then get another chance to learn one's lesson and move on.

"He's a little cracked, a little shopworn around the edges, but once you get past that you see he is really a thing of beauty, a vessel to be filled with knowledge that he can dispense to others. I just love him, despite his flaws, and I think he is perfect! Why? Because I made him of course!"

Very well put STL.

Sometimes one is to follow the crowd as tho to beleive in order to strive in it!

No god=mc²

Fundamentally, it is an intuition. Something probably which poets could illuminate far better that engineers. To an engineer, it is something...that which is tried to be modelled...that leads to something else but explains at the same time. It is not so important to know what energy is in the sense that you ask, so long as what you can observe conforms to whatever sense of it, of energy, that you can conjure. An abstraction premised on cause and effect. A somethingness about which one can only ask about effect, not about existential being.

BTW: reference to humankind as insignificant would be a fallacious statement, neither provable nor unprovable; neither relevant nor irrelevant. One is not bound to follow the herd's obsession with perverse self effacement. To think for one's self is to recognize that one's universe is the only universe one has. If one is insignificant, then the universe is insignificant. If not, then not.

I may be begging the question, but how about, similar to the difference between light and darkness, energy is anti-matter?

What better way to point out the nature of the original question, than to beg a beggered question. Well done...after a fashion.

I may be begging the question, but how about, similar to the difference between light and darkness, energy is anti-matter?

Boy, that is a stretch. I thought Einsteinian physics related energy as another form of matter, positive matter. Don't use light and darkness as an analogy. There is a danger there. Darkness is the absence of light. But anti-matter (if it really exists) is not just the absence of matter, more like the "inverse" of matter. But that is not quite right either. It is what it is (E-prime be hanged!), the negative or polar opposite of positive matter. "Zero" as a number is the absence of any quantity, but it is not the inverse of any quantity, nor is it the negative of any quantity. When you had add negative and positive quantities of the same magnitude you get... "zero". Similarly, or so the theory goes, when you put matter and anti-matter together, they anhilate each other, yielding...what!?! ENERGY? So "Energy is zero"? No, that would be like saying "Fish is Laughter", or "Knowledge is Good" , ooooor, "God is Love", .....wait we may be onto something..... Naaaaaah!

Confused? Me, too!

"Similarly, or so the theory goes, when you put matter and anti-matter together, they anhilate each other, yielding...what!?! ENERGY?"

I've always wondered about this...it seems curious that matter and anti-matter would convert to the same type of energy. Is there a hint here as to the true nature of energy; that it can form both matter and anti-matter? Or are we missing anti-energy, as well?

"when you put matter and anti-matter together, they anhilate each other..."

Wonder why that is anyway? Why do they just "anhilate" each other" That sounds so final. And what do we get out of all this anhilation, energy, right?

So if I place a strong positive charge upon myself (insulated shoes, etc.) and my enemy places a strong negative charge upon himself, and we then come into contact with each other resulting in both of us being anhilated, do we create useful energy? Wait a minute, maybe that's not such a good idea...

"Today's Standard Model shows that every particle has an antiparticle, for which each additive quantum number has the negative of the value it has for the normal matter particle."

Where are all these anti-particles anyway? Why don't we encounter gamma rays being produced from anhilations all around us, especially if EVERY particle has an antiparticle? Why hasn't the entire universe been anhilated by massive particle/antiparticle contact?

-John

So if I place a strong positive charge upon myself (insulated shoes, etc.) and my enemy places a strong negative charge upon himself, and we then come into contact with each other resulting in both of us being anhilated, do we create useful energy? Wait a minute, maybe that's not such a good idea...

Yes, not such a good idea at all!

First of all, do not confuse electrical charge with the state of matter. You have suggested an analogy nothing more. Although analogies can be useful in learning and investigating, the key thing to remember about analogies is that, eventually they always breakdown. An analogy is NOT an equality. An analogy says one thing IS LIKE another. An equality says one thing IS another!

Second, if the equalization of charge results in a strong enough flow of current across your heart muscles, than yes, one or both of you could be anhilated, in the sense that your life would be terminated, however, your physical bodies would remain (at least for the time being). However, the only energy that would be liberated (but not actually created) would be a small amount of heat, especially at the point of contact, as the electrical current passed through your bodies.

Believe it or not, I actually know the difference between analogy and equality. The analogy was stated with tongue planted firmly in cheek.

What do you mean, saying what you mean? Stating an analogy does not mean that it means equality, even when someone else reads it and thinks that it means what it does not mean. Maybe you're just mean today. I think I'll tell Dell.

So if I place a strong positive charge upon myself (insulated shoes, etc.) and my enemy places a strong negative charge upon himself, and we then come into contact with each other resulting in both of us being annihilate, do we create useful energy?

-----

In this case your enemy has an excess of electrons, and you have a dearth of them. If you lack exactly the same number of electrons as he has a surplus, then when you come into contact with him those electrons will migrate to you and occupy the vacancies. You may feel it as a shock. You are positively charged because the electrons that you lack are plucked from some of the atoms that make up your body. Where the atoms lack one or more electrons, some of the positive charge at the atoms' nuclei peeks through (due to the positively-charged protons present there). When you meet the electrons fill the vacancies in your atoms and both of you will each have a net charge of zero.

In the case of matter vs antimatter, say electrons vs positrons, the picture is vastly different. The positron isn't lacking an electron, as in your case, it actually has a positive charge. The result when they meet is a burst of gamma rays. The mass of both particles is converted entirely into energy.

Here's one to bake your noodle: when an electron (having a negative charge) collides with a proton (having a positive charge), the result is a neutron - a neutral particle having no charge. After a short time the neutron will decay back into a proton, forming a plain old garden-variety neutral hydrogen atom. Nothing is annihilated in the process. So why, then, do positrons (having a positive charge) and electrons (having a negative charge) annihilate each other when they meet, and electrons and protons when they meet do not?

"when an electron (having a negative charge) collides with a proton (having a positive charge), the result is a neutron - a neutral particle having no charge. After a short time the neutron will decay back into a proton"

So what happed to the electron?

"why, then, do positrons (having a positive charge) and electrons (having a negative charge) annihilate each other when they meet, and electrons and protons when they meet do not?"

It's obviously much more than a question of charge. I think maybe the quantum strings and the anti-quantum strings have a knock down, drag out fight. Their strings get so entangled that they become some other kind of particle, one that is not (yet) observable to us.

If you have an answer, e, I'd sure like to hear it.

-John

So why, then, do positrons (having a positive charge) and electrons (having a negative charge) annihilate each other when they meet, and electrons and protons when they meet do not?

I think it must have something to do with the relative velocities and also relative momentum. In the electron/positron collision relative velocity may be extremely high, yet mass is extremely low, so the net energy of the collision may be very high, based on the square of the velocities (second order), but momentum is relatively low, where mass and velocity effects are both of the first order. Neither particle has a particularly high rest mass, and relativistic mass may be even lower, so perhaps then momentum need not be conserved, but energy must.

On the other hand in the electron/proton collision, the overwhelming mass of the proton would absorb the tiny mass of the electron. We know this to be nearly true, since the mass of a neutron is slightly higher than a proton.

However, it is much more complicated than that. Here is a discussion of proton versus neutron mass:

http://www.newton.dep.anl.gov/askasci/gen01/gen01078.htm

Velocity and momentum play no part in determining whether a specific pair of particles can annihilate to produce pure energy. For annihilation to occur, the two particles must have quantum numbers that sum to zero. Therefore an electron and proton cannot annihilate each other into pure energy (although with enough collision energy particles, they could produce a different set of particles). But an electron and positron (or any matter particle or ensemble and its exact antimatter counterpart) -- since their quantum numbers add up to exactly zero -- can annihilate.

By the way, I find it surprising that an engineer wrote "... so perhaps then momentum need not be conserved". Has anyone ever reproducibly observed non-conservation of momentum in any context?

By the way, I find it surprising that an engineer wrote "... so perhaps then momentum need not be conserved". Has anyone ever reproducibly observed non-conservation of momentum in any context?

No, I am just showing my ignorance. Never really understood what goes on at the subatomic level. Thought maybe some of the rules were different. I must have dozed off during the "Quantum Mechanics" lecture in General Physics. Just took a WAG.

Thanks for the enlightenment!

Fair enough -- with all the quantum weirdness that apparently occurs at the sub-atomic level, maybe we can speculate about non-conservation of momentum without sounding too outrageous. But as far as I know, the 1st and 2nd laws of thermodynamics, and conservation of momentum (both linear and angular) apply even in such an unusual setting. If anyone proves otherwise, this would imply the possibility of perpetual motion machines and reaction-less drive.

Gollee!

Best answer I have seen so far, as far as I can understand it anyway!

I would love to know more about your "thermo-dynamic unification" and how is it your own contribution? Have you published a paper on this? Just curious.

I wonder what Jorrie and Fyz think of this one.

Maybe we should just ask the molecules why the application of thermal elements causes them to go all kinetic???

Working the problem backwards, a technique engineers use sometimes, start by defining 'really'. Does it refer to an illusion brought on by an absence of alcohol or hallucinogenic substances, both legal and otherwise?

What do we mean by 'What do we mean?'

Del the cat!

What do you mean, "What do we mean by 'what do we mean'?"

Mark

"Del the cat! What do you mean, "What do we mean by 'what do we mean'?"

I think he means that he wants someone to define the meaning of the phrase "what do we mean". His meaning is plain. What else could he mean? It could be HE is mean, knowing that the mean answer would probably be meaningless to the mean individual who is not mean. Understand my meaning?

ROFL

In one my earlier posts in this thread I stated that we should define "energy" in terms of what energy *does*, not what it "is". Now I will give my definition:

The word "energy" denotes the ability of a system to move matter against an opposing force.

To elucidate what I mean, we should look at specific examples. But first I must point out that we can only observe energy when it inter-converts between two different forms. Furthermore, in each pair, we can label one of the energies as "active" and the other as "potential". Example 1: Conversion of chemical energy (electromagnetic potential energy) into heat energy. When a chemical fuel burns, the molecules in the vicinity of the flame increase in temperature. This means that the average speed of these molecules increases. For this to happen, the molecules must accelerate against the opposing force of inertia. Example 2: Conversion of kinetic energy into gravitational potential energy. If we push a disabled automobile to the top of a hill, we do so against the opposing force of gravity. Example 3: Conversion of light into electricity (electromagnetic potential energy). When a photo-voltaic cell absorbs light, electrons escape the cell's surface by travelling against an opposing electromagnetic force. Example 4: Conversion of kinetic energy into nuclear potential energy. Most people know that we can harness energy from nuclear reactions. But, less obviously, we can in principle (but not economically) also manufacture nuclear fuel by using a cyclotron to bombard certain elements with charged particles. During this process, the precursor's atomic nuclei capture the charged particles, causing the nuclei to deform against an opposing nuclear force into a less stable (radioactive) arrangement.

Of course energy conversions can occur by other routes not mentioned above. In total, I think we could enumerate about 24 different permutations (taking into account that conversions can occur either from potential energy to active energy, or from active energy to potential energy (see below for an explanation of my terminology).

Now I present my attempt to innumerate the basic categories of energy (the ones we know about). I welcome feedback.

1. "Active Energy"

1a) coherent kinetic energy -- a group of molecules all moving together in the same direction. Examples: speeding bullet, speeding locomotive, sound waves.

1b) incoherent kinetic energy -- collection of randomly moving molecules, aka "thermal energy" or "heat".

1c) radiant energy -- travelling force-carrying particle/waves. These come in three subtypes, corresponding to the gravitational, electromagnetic, and nuclear forces: photons, gravitons, and bosons.

2. "Potential Energy"

2a) Gravitational potential energy -- the energy available due to the relative positions of two or more masses in a gravitational (or inertial) field. Example: water behind a dam.

2b) Electromagnetic potential energy -- the energy available due to the relative positions of two or more electrical charges in an electromagnetic field. Examples: chemical fuels, electricity, compressed spring.

2c) Nuclear potential energy -- the energy available due to the relative positions of two or more subatomic particles (protons, neutrons, and/or quarks) in a nuclear (strong force) field. Examples: fissionable isotopes, and elements like hydrogen which can undergo nuclear fusion.

Hi svengali,

Interesting post.

Let me play devil's advocate for a moment:

You said 'I stated that we should define "energy" in terms of what energy *does*, not what it "is".'

The original question was "What is energy?" Defining what it does does not answer the question my friend. If the question were "what is an automobile?" and if I answer "it goes up the hill against gravity". That does not, in any way, define an automobile.

You said "we can only observe energy when it inter-converts between two different forms". Does this mean that when it's not in conversion, it does not exist or only that we can't see it before conversion occurs? If we simply can't see it, is it there or not? Once conversion has completed, does energy then just disappear, or does it somehow then become something like dark energy/matter and no longer a part of the observable universe?

Does potential energy actually exist, or is it just somehow a precursor to some event waiting to happen? If a wagon is sitting at the top of an inclined plane with its wheels chocked, maybe we should say "there lies potential just waiting to become energy".

Why can't we observe energy in its naked, unadulterated state?

I think you hit it on the head though. From all of your examples it seems that the true definition of energy, as you present it, is: Energy = motion against an opposing force.

But then if I'm flying my glider with a strong tailwind, is my glider expending any energy?

Cheers

Excellent points Johnjohn! Or were you just making points for The Devil?

The original question was "What is energy?" Defining what it does does not answer the question my friend.

To me the question "what is energy?" seems meaningless (or more tactfully put, in need of better wording)

If the question were "what is an automobile?" and if I answer "it goes up the hill against gravity". That does not, in any way, define an automobile.

Please indulge me and give your answer to "what is an automobile?". We will see that you define it either in terms of its function (what it does) or what it consists of. Since we cannot break down energy into simpler components, that only leaves the option of describing what it does (how it influences other observables).

You said "we can only observe energy when it inter-converts between two different forms". Does this mean that when it's not in conversion, it does not exist ... ?

No, when not in the process of inter-converting, you can think of the energy as existing in a "potential" state. Think of a battery -- obviously its energy content (electromagnetic potential energy) does does disappear when not in use.

Once conversion has completed, does energy then just disappear, or does it somehow then become something like dark energy/matter and no longer a part of the observable universe?

No, energy *never* disappears (well other than travelling out of view into deep space). Once an inter-conversion finishes, the energy exists as potential energy again. Give me any real-life example, and I'll try to specify more precisely.

Does potential energy actually exist, or is it just somehow a precursor to some event waiting to happen? If a wagon is sitting at the top of an inclined plane with its wheels chocked, maybe we should say "there lies potential just waiting to become energy".

A fascinating question that I have previously mentioned in this forum. We know that nuclear potential energy manifest as increased mass. For example, a pair of deuterium atoms together possess slightly more mass that the helium atom that they would produce via nuclear fusion (our local star "Sol" loses millions of tons of mass per second due to this matter-to-energy conversion). That extra mass in the deuterium atoms equates to their nuclear potential energy. I don't like the idea of "potential energy" as a purely abstract concept, so I propose that the other forms of potential energy -- electromagnetic and gravitational -- also manifest as increased mass. If true, then the wagon at the top of the hill would have slightly more mass (compared to the same wagon at the bottom of the hill). Likewise, a compressed spring, or a charged battery would also have slightly more mass. But because of the huge conversion factor c^2 in E=mc^2, existing technology cannot yet measure these extremely tiny mass differences.

Why can't we observe energy in its naked, unadulterated state?

We can only detect energy via its interactions, during which it inter-converts with other forms of energy. By the way, the Buddhist have know this for over 2000 years.

I think you hit it on the head though. From all of your examples it seems that the true definition of energy, as you present it, is: Energy = motion against an opposing force.

But then if I'm flying my glider with a strong tailwind, is my glider expending any energy?

Thank you. And, yes, once airborne you and your glider perform work by pushing on the air below -- you get to spend the gravitational potential energy that you earned on the way up!

I agree that in most cases it is against an opposing force, however, there is cases where there is no opposing force.

An object travelling through a vacume with no opposing force will continue to travel and retains the potential energy of its mass X speed. I think we have to simplify it further to say it is simply "a quantified amount of motion"

It is simply the transfer or storage of "motion"

Potential energy is equal to the total movements of all the particles (spinning, vibrational, and internal movements of particles.

More energy = either higher speed, and/or more objects moving.

I will not pretend that I understand quantum physics, although I do keep trying. All this talk about what is energy makes me wonder about STRING theory, what would a vibrating string of energy be? At this time it is believed to be the fundimental building block for everything, is it not?

JB

What, then, is a "string?" Do you see the problem?

We ask what energy is, but like time, space, mass, charge, and so forth, we use these fundamental quantities without really knowing what they are. On what fundamental basis do they exist? Why them, particularly, and not something else?

But even if someday we could "look under the hood," we'd simply be pushing the problem farther backstage. If we discovered someday that energy is based on something even more fundamental, we'd be asking the same question about that more fundamental quantity. What is that quantity? What is it really?

We take energy as axiomatic and we take for granted its existence without understanding it at all. We've learned to harness it, manipulate it, measure it, describe some of its relationships with other fundamental quantities, and so forth, but we don't really know what it is. What it really is. Nothing at all.

Excellent post e.

We do keep "looking under the [current] hood" don't we? I wonder just how far back we can "push" the problem before we say "I give up!", anything further is unknowable (Naaah, won't happen)

I agree. Whether it be energy, time, space, etc., we really don't know what they are.

Does time exist except at this current instant? How small a slice of time will define the current instant?

What is the "fabric" of space-time anyway?

If I can place something with "mass", say, in my right hand, and mass and energy are equivalent, why can't I place energy in my other hand? But then, the "mass" in my right hand is energy isn't it? As I look at it I only see a mass though.

If I then lift the mass overhead, I'm actually lifting energy or is it my muscles that are the energy here (according to svengali energy is motion against an opposing force).

You're dead on e, we just don't understand a whole lot do we?

Regards,

-John

Good post. And I agree that we might not ever know (with complete confidence) what "ultimate" fundamental particles underly physical reality. Maybe we'll just keep finding more layers of fine-structure as particle accelerators keep applying ever-increasing amounts of energy. To me this seems like more evidence that the concept of "isness" deserves scrutiny. Our understanding will probably progress faster and further by studying the web of interactions linking objects, rather than the absolute structure (or "isness") of objects in isolation. Of course we already accept this in biology, ecology, psychology, and sociology. More recently, many particles physicists have already accepted this in regards to studying quarks. Using higher levels of energy to try to force quarks apart from each other failed completely -- the energy instead manifested as more bound quarks!

Using higher levels of energy to try to force quarks apart from each other failed completely -- the energy instead manifested as more bound quarks!

-----

We needn't go so far as probing the nature of quarks! Take the lowly electron.

In spite of all we know about electrons, they continue to remain an enigma. An electron has mass and charge; this we know. But no matter how deeply we probe this "particle," no matter how high the energies and resolution of our best instruments, no matter how many scattering experiments we conduct, we simply cannot determine an electron's size. So far as we know it has no size. Not even a little! There just isn't anything there! Nothing but mass and charge. There's no "stuff" - not even quarks. Just charge and mass, and swarms of virtual particles that flicker in and out of existence.

Even more mind-boggling is the fact that this thing - whatever it is - has spin. But this also means it has an orientation. Judas Priest! How is it possible for something having no physical extent at all to have an orientation? And have spin? What the heck is spinning when there's nothing there? Worse, what does spin mean when the thing you're talking about has no radius? This thing has none, yet it behaves as if it really were a spinning thing (with the quantum provision that the spin is either completely one way or completely the other with no in-between states).

So we have mass without stuff and without size. Apparently, then, mass in the most fundamental sense doesn't particularly depend on something having a size. Apparently mass doesn't have to occupy space. Off-hand I'd say there seems to be much more (or less) to mass than meets the eye.

And what about an electron's charge? What, exactly, is charged? There's no stuff. There's no size. What localizes that mass and that charge to that particular point in space? What makes that point special and not another point? What lends that point in space those properties? What is there, anyway?

Better yet, why is it there?

As a chemist, I think often think about how the number and arrangements of valence electrons determine the chemical properties of elements and compounds. But I've never given much thought to the properties of isolated electrons. Man, your description blew me away. I knew electrons belonged to the set of "fundamental" particles and could not be subdivided. But I had not consciously considered their inconceivable weirdness. Kind of makes my head hurt!

Man oh man e,

I thought I was perfectly comfortable with the lowly electron but you blew my away with that post.

Mass and spin without size! That's completely mind boggling to say the least.

If the electron cloud has whorls and vortexes within it, might that somehow be interpreted as spin? Electron cloud shown here in black (helium atom).

-John

Here's a thought experiment that anyone can conduct, even the CR4 reader.

Turn off the light and blacken the room. Wear ear-defenders. Stop tasting and smelling and touching things for the moment. Sit there and wait until all is still. No inputs.

Where is the universe? Answer, it's in the mind! Everything mankind knows about the universe is stuff that has come in via various sensors and has been assembled in to a beautiful, complex, terrifying (at times) image projected onto the inside of the cranium!

Mass, energy, charge, length, spin etc. are all concepts.

That's a good experiment...now try it hoding your penis....

Does it put the other concepts into perspective?

Turn off the light and blacken the room. Wear ear-defenders. Stop tasting and smelling and touching things for the moment. Sit there and wait until all is still. No inputs.

Reminds me of Dr. John Lilly's experiments with sensory isolations tanks (floating motionless in neutral-buoyancy body-temperature salt solution, inside light-proof sound-proof tank). Even without using any psycho-active drugs, the mind soon begins to manufacture sensory experiences (hallucinations) to make up for the lack of the usual inputs. Some researchers propose this "manufactured-inputs" phenomenon as part of the reason we dream during sleep (to keep the mind occupied while the body rejuvenates).