What is Energy?

Okay - this is really bothering me. You're all a lot smarter than I, so of course I turn to you first (well... second, after Wikipedia) for answers.

I've been reading Denis Brian's biography on Einstein and the book contains lots of references to something called "energy". It says stuff like

"everything in the universe is a repository of enormous, latent energy"

"the formula implied that mass is frozen energy"

"every gram of matter contains this tremendous energy"

Over the years I've also talked to lots of spiritual types who like to tell me about 'energy envelopes' and chakras which are apparently an energy. The body has an 'energy aura'. My friend Sailor Bob the guru likes to say that the universe is "intelligence energy".

 So I went looking for a definition of what this thing called 'energy' really is.

Wikipedia was, of course, my first port of call. It says:

In general, the concept of energy refers to the potential for causing changes. The word is used in several different contexts. The scientific use has a precise, well-defined meaning, whilst the many non-scientific uses often do not. In physics, energy is the ability to do work and has many different forms (potential, kinetic, electromagnetic, etc.) No matter what its form, physical energy has the same units as work; a force applied through a distance. The SI unit of energy, the joule, equals one newton applied through one meter, for example.

Okay, so what is the precise scientific meaning of 'energy'? Until 1807, scientists used the term 'vis viva' (latin for 'living force') instead of energy, which sounds similar to the way it's often used by my spiritualistic friends. So what does Wikipedia say the term means now?

The concept of energy change from one form to another, as a "driver" for natural processes, is useful in explaining many phenomena.

... in the context of physics energy is said to be the ability to do work

Okay but.. what is it? What is it made of? Can I touch it or smell it is visualize it in any way? The chemical and biological definitions for energy are similarly vague. The term gets used like there is an a priori understanding on behalf of the reader that energy does, in fact, exist. And yes I still don't know what they are talking about. It reminds me of talking to spiritual friends about "soul". What is it? They cannot tell me, just that they believe it exists. It seems about as good as I can get for "energy" as well.

Wikipedia also has this to say:

During a 1961 lecture for undergraduate students at the California Institute of Technology, Richard Feynman, a celebrated physics teacher and a Nobel Laureate, had said "There is a fact, or if you wish, a law, governing natural phenomena that are known to date. There is no known exception to this law -- it is exact so far we know. The law is called conservation of energy [it states that there is a certain quantity, which we call energy that does not change in manifold changes which nature undergoes]. That is a most abstract idea, because it is a mathematical principle; it says that there is a numerical quantity, which does not change when something happens. It is not a description of a mechanism, or anything concrete; it is just a strange fact that we can calculate some number, and when we finish watching nature go through her tricks and calculate the number again, it is the same..."

So Feynman says it isn't a thing as such. It's a principle. An abstract idea. A useful imaginary premise. I found this quote somewhere else: 

"It is important to realize that in physics today," says Richard P. Feynman, "we have no knowledge of what energy is." Feynman was one of the three recipients for the Nobel Prize in Physics in 1965 for his contributions to quantum electrodynamics and was one of the most influential physicists of the 20th century.

We don't know. No idea. This bothers the HELL out of me. Scientists use this term every day but nobody knows what it is??? It's one thing for spiritual fairy people to use vague terms, I kind of expect that. But I hold science to a different standard. It's okay for fairy lovers to accept "belief" over evidence and rational thinking, but I expect scientists to be my source of deep thinking about the true nature of things. I expect the scientific method, a process for evaluating empirical knowledge under the working assumption of methodological materialism, which explains observable events in nature as a result of natural causes, rejecting supernatural notions. As yet the definitions of "energy" I can find seem about as supernatural as they come. It's almost enough to make me buy some prayer beads.

With respect to uses of the term "energy" in spirituality, Wikipedia says this: 

... refers to a widespread belief in an interpersonal, non-physical force or essence. Vitalism is a general term for a force that animates living things. Believers consider spiritual energy to be of a different type than those known to science. Various ideas pertaining to spiritual energy have been postulated in various cultures, prominent amongst them are: 

• The Christian idea of the soul or spirit
• The traditional Chinese qi
• The Indian chakra or shakti
• The New Age/paranormal aura
• The "orgone energy" of Wilhelm Reich
• The morphogenetic fields of biologist Rupert Sheldrake
• The Odic force of chemist Carl von Reichenbach
  
  Various forms of mysticism often associate "bad energy" with disease, and "good energy" and healing powers. Most theories involve the ability to actively influence one's energy.

Okay... no help here? These definitions seem to try to define one word with an equally vague word. Energy is Soul. Riiight. So Sayeth The Flying Spaghetti Monster.

So if anyone out there can help me understand what energy really is, ping me. Come on G'Day World and enlighten us all.

Comments

[Gran Jan]

Yeah...Well I can't see the wind or touch it, but I can see & feel it's affects.

[Cameron Reilly]

Yes Mum... and I can provide a rational, scientific explanation for what "wind" is.... "the roughly horizontal movement of air (a mixture of gases, mostly nitrogen and oxygen with some water vapor, surrounding the earth) caused by uneven heating of the Earth's surface."

If you say you feel the effects of something, you should be able to provide a rational definition for what that something actually is. Otherwise, how do we know we aren't kidding ourselves and still living the the Dreamtime where giant snakes swallow the world every evening?

[granjan]

We don't know. As yet not everything can be explained scientifically. That doesn't mean it doesn't exist. It just means we can't prove it. I use electricity but I can't really explain it. I know a scientist may be able to come up with some sort of explaination, but from what I've read they don't really understand it either. Some things we just believe, rightly or wrongly. As long as it works for our benefit, what does it matter? Perhaps it is simply the "belief" that makes it work.

[Cameron Reilly]

I don't like the electricity analogy and here's why. You may not know much about how electricity works, but both of us can do some simple experiments to prove that it works the same way for both of us. You flick the switch and I flick the switch and the same thing happens every time. There is an observable result to a set of actions. It has nothing to do with belief. It is verifiable. Whether you believe in the electricity or not, it still works the same way every time.

[Tony]

Love posts by you Mother Reilly.

Love the spaghetti monster anolgy to Cam. Some say that God exists but they can't prove it so who is to say there isn't a Giant Spag Monster.

I have no idea how to define energy..it just is.

[Cameron Reilly]

Tony, don't encourage her. Senility is a terrible thing. :-)

As for "it just is"... that doesn't bother the crap out of you?

[Mark C.]

Pretty cool stuff. It is funny how people rely on the verbage of priests or scientists, while no one actually knows what the hell is going on.

Another one is 'Evolution' which explains the process but I don't believe answers why things want to reproduce in the first place.

It reminds me of one of the names for intelligence energy of the Advaita Show 'What the Fuck? Shutup'

[Grant]

Hi Cam - I actually think electricity is a good analogy. There are lots of experiments you can do to prove energy (electro-magnetic, kinetic etc.) but no way to verify it. Electricity is actually the same thing. It is a form of energy. But what it is? Who really knows.

I think what you've stumbled across is what I like to call "science as religion". If you look at the theory of evolution, there are stumbling blocks along the way. No-one can fully explain it, yet most of us take it for granted. The "big bang" theory upon which so much science is based? Theory. Nothing to prove it.

And then you get into quantum physics which more and more looks to me to be the scientific pursuit of what the Chinese worked out centuries ago - all that Zen Buddhism looks tame compared to some of what comes out of that work.

There are so many things out there that are unexplained, and yet we take them forgranted. Because we can recreate the effect, we call it a law, yet often the laws come from observation alone - that is because we can reproduce it we feel we can understand it. But those foundations are often very slim.

Don't get me wrong, I'm all for science - I think trying understanding our world at a scientific level is an essential thing we should be doing. I also have spiritual beliefs. But the older I get, the more those two worlds are seeming to converge.

Regards, Grant

[Miriam Parkinson]

The wikipedia article is probably the closest to a definition we have available to us. Energy is like many things, we don't know what it is but we can prove that its there, and we can predict with almost total certainty what it will do in a given situation... and if you can do those two things then why do we need to know what it is.

And as far as the mass-energy thing is concerned, mass is a form of potential energy. In much the same way as food contains chemical potential energy, mass is what you could call 'nuclear potential energy'. Simple.

Now I think of it...

Define mass...

[Tony Goodson]

What is Energy?
What is Mass?
When you find this person to interview on G'Day World, can you also ask them What is Gravity, and What is Light.

Energy and Mass, I can just about cope with, but this Gravity thing is a bit weird. If there is a big planet and another big planet, and they're quite near each other, and we chop one planet up into little pieces to investigate its Energy and Mass, where is the gravity bit that the planet is feeling from the other planet? And in the space between the two planets, where is the gravity that's transmitting between the two planets?

And how can light be a wave and a particle?
Is it a wavey particle?

I think Father Bob will have the answers, because science has become the new religion. Declarations are made that have been "Scientifically Proven" so it must be true then!!

[Tony]

Funny you mention gravity Miriam. I was standing on train platform this afternoon thinking about all this and it crossed my mind that gravity will fall into the same category as something that we can't really explain but we know it is there. why does it work and why do diff worlds have different levels of gravity is the same as the energy question i think.

[Lindsey]

If you approach existential analysis from a Rene Descartes inspired reductionist perspective, you nearly always eventually run into foundational axioms. An example of a mathematical axiom is the familiar 1 + 1 = 2. Or to put it more correctly but confusingly, “Two things equal to the same thing are equal to each other, if A + A = B, then A = A” Can't actually be proved other than by general observation.

Axioms are the Academic's way of answering Professor Julius Sumner Miller's question, "Why is it so?" with a sexed up version of 'Because it just is, stupid!' Take a closer look at the bleeding edge of current physics research and you'll see that it is encroaching deeply into the realms of mysticism. Schrödinger's cat is well and truely sick of being in that bloody box.

Piers Anthony's wonderfully funny alternative world of Xanth series of some thirty plus books makes great use of messing with foundational axioms of reality in a very quirky way.

[Miriam Parkinson]

gravity is energy... gravitational potential energy.
As in if you lift something up to a certain point you are converting chemical potential energy (stored in your body) to kinetic energy (moving your hand) to gravitational potential energy (as in if you let go of the object it will fall).

Then if you let go of the object it returns almost all of this energy as kinetic energy with some losses in deformation energy, heat and sound.

[Mr Oneness]

For me, I see our entire existance, this whole reality, simply as ONE energy. We are all a part of this energy field. This Energy can never be created or destroyed but simply continues to change forms ...life is weird huh?... I have a deep sense that energy is the force that moves all things...

[Cameron Reilly]

I agree with you Mr Oneness, but WHAT IS IT? What is this "energy" you speak of?

[Miriam Parkinson]

I've been trying to record a bunch of clever clogs giving their definitions but unfortunately for you the only definitions for energy that are available to us are rather circular.

Energy is the ability to do work. Work is a force applied over a distance. A force is the tendency to change the state of rest or motion of a mass. E=mc^2 so Mass is simply a whole lot of potential energy and suddenly we are back at the start.

We don't know what energy is. Energy is simply a term that we use to describe a phenomenon that we observe. Like time. We experience the passing of time however it has no existence outside the boundaries we put on it. We have invented a system to measure an experience in exactly the same way as we invent energy to describe and measure something that we know happens.

As far as can you touch it... Yes and no.

When you feel cold it is because the environment is taking heat energy from your body. When you feel hot the opposite happens. If you ground a live wire via your body you know all about electrical energy and when you drop a brick on your foot you are feeling deformation energy caused by the kinetic energy of the brick which is caused by the gravitational potential energy. You can see because of electromagnetic energy which also makes your microwave and your wireless work (well mostly work).

So you can't touch energy but you can experience energy.

[Cameron Reilly]

Thanks MIzza, but really, doesn't that all seem a bit "new age" to you? You can't see it, touch it, we don't know what it is, we can't define it, but you can "experience" it? How do you know you aren't actually experiencing the magical power of the wawa tribe?

[Miriam Parkinson]

We don't know and we don't care.
As an engineer my chief interest in physics is how it applies to my robot not falling to bits/going through walls/killing people(assuming that its not designed to do any of this stuff in the first place). All I care about is that I always know exactly what it's going to do. All of this stuff is really mathematical definitions that we know work for the purposes of predicting and describing whats going on in the universe.

Does it really matter if its the magical power of the wawa tribe? All we care about is that it makes mathematical sense and that its not about to change all of a sudden.

[Mr Oneness]

I'm with you on this Cameron what is "IT" ? I know "IT" is perplexing and mysterious! :) The fact that our entire existance is held together by "IT" tends to make this an uber important question in my view... Is "IT" Gods love? Is it even possible to have an understandable and/or valid answer on a rational level?... I want to know too.... Lets keep digging...

[Cameron Reilly]

Mizza, you don't care? As a rational thinking person, you don't wonder about this mysticism? This circular thinking? Especially when it comes to something which, we are told, is the foundation of all matter?

Oneness, isn't the definition of "God" equally as troubling as "energy"? So "energy" = "IT" = "God's" love? I'm none the wiser.

[Miriam Parkinson]

Cam the essential problem is that we don't really know what anything is. We assign definitions and rules to the universe to make sense of it but we don't by any stretch of the imagination understand it.

We say that the speed of light is constant in all intertial frames of reference. We say this because our observations tell us this is the case. We have evidence to prove it however we do not know that it is definitely true. However, until someone is able to disprove it we will accept it because it works and that is all that matters.

I mean take quantum physics and General Relativity.
Both work, both have been demonstrated and are almost universally accepted by physicists. However they contradict each other. One cannot be rationalized with respect to the other. Einstein himself made a complete arse of himself by trying to disprove quantum physics and in his time eventually disappeared into obscurity, not even being invited to scientific meetings and conventions because he was so determined to make a fool of himself.

Scientists are really just philosophers the only difference is that they work in the physical world not the spiritual.

[Cameron Reilly]

I don't mind a certain level of abstractiveness when we take a reductionist view of the universe. What bothers me about "energy" though is that the term is bandied about by everyone from scientists to new-agists as if they know what it is. As if it *is* something. As if it has certain quantifiable properties, can be measured, can be understood. But as far as I can tell, the term "energy" is a catch-all for "shit we don't understand". It's the modern day equivalent of "ether". It's like saying "look, we see shit happen, and we don't know why, but there must be SOMETHING doing it, so... we'll just make up a name for it and let's move on. Oh look at this pretty blue flower!"

When people tell me "the whole universe is made of energy", I think it's a pretty fair question to ask "great what's that then". The answer "ummm I don't know" doesn't really work for me. It isn't good enough. This is 2006. We can do better. Let's stop using made up words that don't mean anything more than "something that does stuff".

[Miriam Parkinson]

yeah well there's another very important problem with the universe.
At some point in time either something came from nothing or it was always there. Neither of those are rationally possible.

Whilst we don't know what it is we know what it does, and in a way it amounts to the same thing.

Here's another way of looking at the problem. If you can accept every form of energy then you have by definition accepted energy.

Electricity: You have already said is fine.
Gravity: When you drop stuff it moves towards the biggest mass... earth
Kinetic: stuff moves
Heat: Moves from high concentration of heat to low concentration of heat. You touch something with alot of heat energy it attempts to equalize the temperatures by transferring a whole lot of heat energy to you and burns you in the process.
Deformation: If you squish a can you cause a permanent change in its shape
Sound: you can hear stuff
Electromagnetic: your radio works, you can see (well theoretically anyway)
Nuclear: E=mc^2 and all that junk. Breaking up atoms releases energy.
Chemical: food has energy in it kj and all that junk that people like to count.

I will have missed some but there it is...

Really I guess energy is a big umbrella term to describe all of these things because whilst you can turn any one of these forms of energy into any other one, the system as a whole is closed. There is only a certain amount of energy in the universe.

Think of it as a mathematical convenience.

[TT]

Listen up people, Energy is not something one should think of as concrete, in a tangible or intangible sense. When someone claims that a falling tree has a certain amount of Energy, all they are saying is that it is comparable to a brick being dropped from a window(Mathematical exageration). They are not saying that it possesses some magical power; Just that it has a potential value to move, explode, heat, etc.
It is a way of measuring affects, like when I say a piece of lint could burn you equally as bad as a camp fire. In reality, lint cant burn anything. But If I had the knowledge, I could collapse the atoms, and cause an explosion to burn myself to a degree equal to a camp fire(exaggeration). Is that easier to understand than saying, A camp fire has the same amount of Energy as a piece of lint?
Energy is just a (numerical) value to compare and contrast the affects of matter. (Like when I put a red hot spoon in water, its temperature and mass are going to decide how warm the water will be. But if I put it in terms of energy, then I can find out how many light bulbs the spoon could illuminate, how many miles it could destroy, as well as how much it heats water.)
Asking, "What is Energy" is like asking, What is temperature? or What is a pint?

[Miriam Parkinson]

Exactly energy is a convenient measuring stick.