Physicist: Unfortunately, “pure energy” isn’t really a thing. Whenever you hear someone talking about something or other being “turned into pure energy”, you’re listening to someone who could stand to be a little more specific about what kind of energy. And whenever you hear someone talking about something being “made of pure energy”, you’re probably listening to someone who’s mistaken.
“Pure energy” shows up a lot in fiction, and most sci-fi/fantasy fans have some notion of what it’s like, but it isn’t a thing you’ll find in reality.
Energy comes in a hell of a lot of forms, but they’re all pretty mundane. For example, when “energy is released” in an explosion (most explosions) that energy mostly takes the form of kinetic energy (things moving and heat). Light is about the closest anything comes to being pure energy, but it’s not pure energy so much as it’s one of the several kinds of energy that isn’t tied up in matter. It’s “matterless”, sure, but that doesn’t mean that electromagnetic fields (light) are any closer to being pure than, say, gravity fields (another, very different, massless form of energy). “Pure” energy: nope. Some form of energy without matter: that happens.
So, energy can change from one form into another into another into another, etc., but the question remains: what is energy? The answer to that is a little unsatisfying.
There’s this quantity, that takes a lot of forms (physical movement, electromagnetic fields, being physically high in a gravitational well, chemical potential, etc., etc.). We can measure each of them, and we know that the total value between all of the various forms stays constant, and just like every other every constant, measurable thing it gets a name; energy.
If fusion in the Sun releases energy*, then the amount released is E = (Δm)c2 (where Δm is the change in mass between the hydrogen input and helium output and c is the speed of light). If that energy travels from the Sun to the Earth as light, then each photon of that light carries E=hν (Planck’s constant times frequency), of it. If those photons then fall onto a solar panel, that light energy can be converted into electrical energy. If that electrical energy runs a motor, then the energy used is E = VIT (voltage times current times time). If that motor is used to compress a spring, then the energy stored in the spring is E=0.5kA2 (where k is a spring constant, and A is the distance it’s compressed). If that spring tosses a stone into the air, then at the top of its flight it will have converted all of that energy into gravitational potential, in the amount of E = mgh (mass of the stone times the acceleration of gravity times height). When it falls back to the ground that energy will become kinetic energy again, E=0.5mv2 (where m is the stone’s mass and v is its velocity). If that stone falls into water and stirs it up, then the water will heat up by an amount given by E = C(ΔT) (where C is the heat capacity of water, and ΔT is the change in temperature).
The “same energy” is being used at every stage of this example (assuming perfect efficiency). But there’s no “carry through” that makes it from the beginning to the end. The only thing that really stays the same is the somewhat artificial constant number that we Humans (or more precisely: Newton) call “energy”.
When you want to explain the heck out of something that’s a little abstract, it’s best to leave it to professional bongo player, and sometimes-physicist Richard Feynman:
“There is a fact, or if you wish, a law governing all natural phenomena that are known to date. There is no known exception to this law – it is exact so far as we know. The law is called the conservation of energy. It states that there is a certain quantity, which we call “energy,” that does not change in the manifold changes that nature undergoes. That is a most abstract idea, because it is a mathematical principle; it says 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 a strange fact that when we calculate some number and when we finish watching nature go through her tricks and calculate the number again, it is the same. (Something like a bishop on a red square, and after a number of moves – details unknown – it is still on some red square. It is a law of this nature.)
(…) It is important to realize that in physics today, we have no knowledge of what energy ‘is’. We do not have a picture that energy comes in little blobs of a definite amount. It is not that way. It is an abstract thing in that it does not tell us the mechanism or the reason for the various formulas.” -Dick Feynman
The Green Lantern picture is from here.
*Every time energy is released from anything, that thing ends up weighing less. It’s just that outside of nuclear reactions (either fission or fusion) the change is so small that it’s not worth mentioning.
@John:
“The problem with science is the ego of Wisdom. Like wisdom, the mother of science, science has no foreknowledge, it only relates to tangible history, chemical energy; thus it doesn’t matter what truth exists, if science cannot verify it, it is meaningless to its subjects; even though pure Energy is staring it in the face.”
John, you’re saying nonsense. Energy is INHERENTLY a scientific idea, because it was invented by science, and as such, it can only be meaningful within science. Also, it is not true that if science cannot verify it, then it is meaningless to the subject. Mathematics are not scientific, yet they are meaningful to the subject. However, pure energy is still meaningless as energy was never pure or impure to begin with, energy is just a mathematical quantity we can measure.
@TK
“@Hanson…. The Big Bang, I believe, is one of many bangs, a continual or series that exists and will always: a constant series of super mega size black holes that siphon and squeeze matter through into and out of “white holes” (a starting point of big bangs), like a cosmic chain…it’s perpetual.”
We have little evidence for this, though.
@Sjb:
“Pure energy
Why don’t you all accept that pure energy is something humans of earth can never harness or control at this stage of evolution. Long way to go.”
Because pure energy doesn’t exist. Read comments above for reference.
Challenge Accepted
You say a photon carries energy and this is a wrongful assumption. A photon is energy. The words “photon” and “energy” are synonymous and should not be separated. Like “love and marriage” you can’t have one with out the other.
How does photon can be energy. Rather it is a energy carrier. It is a quantum object that has lot of quantum properties like momentum, spin position etc…
So if I understand this and it matter is just a form of condensed energy then at some time in the future might we teleport people and materials across space? The experiments with quantum entanglement seem to lead one to think it might someday be possible.
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We have one formula for energy. E = MC2. The conversion of mass to energy is well known in the production of sunlight energy. This energy is carried by photons. It is well known photons carry energy so without energy a photon could not exist. The problem remains can energy exist without the photon. My answer is “no” so the solution, it seems to me, is that the photon and energy can not be separated. I would go so far as to say they are the same thing, that the words “photon” and “energy” are synonymous. Maybe we need a new word.
maybe pure energy or other forms of energy is an allusion. something that has emerged from the big bang.