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Topic Title: What is Energy?
Topic Summary: Is Energy a real and definite "thing"? or is it a conceptual and relative notion?
Created On: 14 March 2013 04:19 PM
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 14 March 2013 04:19 PM
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jarathoon

Posts: 1043
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Is Energy a real and definite "thing"? or is it a conceptual and relative notion with no unique definition and without a definite distribution in space?

This might seem a silly question, as we must be payng for something real in our utility bills.

Actually we are paying to convert one form of energy to another (heat and work) at time of our choosing. In terms of a methane we pay for the chemical energy that can be converted to heat, when we burn it. We don't pay for the chemical (or indeed nuclear) energy we can't convert to heat. So even if we knew exactly what we were paying for this "energy" is not the whole story. This is paradoxically the "free" energy to use a chemical term.

I was reading the text recently from a lecture that Prof. E. T. Whittaker gave to the Edinburgh University Physical Society on 16th January 1929.

He sort of starts out with what was the 19th Century scientific view of energy: (what is still the dominant engineering view of energy I expect)

1. Energy is a physically real
2. Energy is a scalar quantity
3. Energy is localised in space (anything that is physically real must be somewhere)
4. Energy is Conserved (it must exist in a certain fixed amount and the amount at any place can only be changed by some physical process of transference)

Whittaker concludes the first part of by saying that in this view energy (in its localisation and transference from place to place) must obey a conservation equation like the "equation of continuity" in hydrodynamics.

Now from the time of Einstein there are element of the new physics that engineers find easy to integrate into their realist view, and elements that they find vey hard.

The view that matter is a form of energy is easy to integrate (E=mc^2), if you ignore how the equation is derived. The conceptual view that total amount of energy in the universe is relative and depends on the frame of reference that you choose is much harder to comprehend. Energy loses it "thinghood" when you can use an arbitary change of reference frame to change its value.

Even more disturbing to the engineer, energy is no longer an independent scalar quantity in General Theory of Relaivity, it has now become irretreivably mixed into the Energy Momentum Tensor.

E.T. Whittaker concludes his lecture

"but we may perhaps be pardoned for some sentimental regret that energy has lost the status of thinghood, and now counts as only one of ten components of a symmetrical tensor of the second rank in the distorted manifold of space and time"

We now have dark energy of course (a form of energy that does not gravitate) yet might well be convertable into mass.

Does anyone know what energy is anymore?

James Arathoon

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James Arathoon
 16 March 2013 12:31 AM
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acsinuk

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Good question
Well, you can eliminate potential energy because energy is movement, or the change of movement. So kinetic energy is real energy and the transfer of momentum to heat represents the external condition of that transfer. However, the internal MC 2 energy is not affected.
Fundamental electromagnetic energy is, I believe the movement of a volume of magnoflux through the internal space inside the electron enclosure. Thus as electrical energy can move at the speed of light, it can have nothing to do with electron particles which are electrostatic by nature representing a potential energy only.
CliveS
 16 March 2013 01:34 AM
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ectophile

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But if kinetic energy is "real" energy, but potential energy isn't, then conservation of "real" energy doesn't apply.

Consider a swinging pendulum. At the mid-point of each swing, the bob is moving fastest, and has a high kinetic energy. At the ends of the swing, the bob momentarily stops - zero kinetic energy. The energy must be "hiding" somewhere, because a moment later it starts moving again.

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S P Barker BSc PhD MIET
 16 March 2013 03:23 PM
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Falciferum

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In my understanding (an engineer's, not a physicist's I must stress!) energy at it's most fundamental level is simply information. Matter is information too, and special relativity tells us energy and matter are interchangeable; energy is conserved in the universe just as matter is conserved because the universe is finite, it contains a finite amount of stuff; matter; energy; information; existence etc.

To speak of energy exclusively I think it is more important to consider flows of energy, after all it is only when energy is flowing does it reveal itself! The laws of thermodynamics tell us that in an isolated system energy flows down a gradient in an irreversible process such that the (macro)state of the system will exhibit increased entropy.

The questions held by me and every other mechanical engineer first taught this is why does this happen and what the hell really are energy and entropy? The number of people I have encountered that give satisfactory answers to these questions is nil. I appreciate then that I stand little chance - but please bear with me! I would love some feedback on my thoughts especially from people with more background in understanding the fundamentals.

Energy (and entropy) is statistical. An energy gradient is, roughly, the natural tendency of a distinguishable, or measurable, quantity of energy (information), whose properties (pressure+volume, or temperature+entropy) can be known for certain, to degrade into an ever-increasing quantity of different distinguishable quantities of energy which must be re-distinguished, or measured for them to be realised. These themselves degrade into a chaotic mess which can never be fully realised because every time a quantity is distinguished/measured/known/realised it just divides into more quantities. This is the increase in entropy - the irreversible process - the arrow of time. Why does it happen? Because for something, with mass and energy, to felt/experienced/measured/known it must be observed, or measured by some interaction in the universe (I think this is where quantum mechanics comes in) but if something is to be observed/measured it must change from that what was measured, if only because the act of measuring and distinguishing has elicited a change in the observer relative to the observed, thus the observed changes relative to the observer in turn. The change multiplies and creates more uncertainty and unknowing demanding more interaction which only serve to do the same in a continuing process that creates ever-increasing uncertainty; entropy. Knowledge is power? Quite literally.

I hope this isn't total nonsense (again, I would love help with this) so to try and insure against wasting your time completely I would like to share with you a great thought experiment taught to me by a materials science professor. It blew my mind and helps to illustrate the informational (or statistical) nature of energy:

Is the process of mixing two colours of paint a flow of energy from which we can extract useful work from some kind of heat engine? Surely not! There's no heat involved? No fuel is being burned? There's no net fluid flow? but it's true, you can!

Paint mixing represents an increase in entropy, and heat is in fact evolved just by mixing paint. After all the paints must be chemically different, their molecules must have different electromagnetic properties otherwise they wouldn't be different colours. Remember in chemistry lessons when just adding some water to some concentrated sulphuric acid created heat? It's the same thing! Generally the paints didn't have to be different chemically to allow for energy to flow - just different in some way that makes sense to us - the observers. We're made of chemicals/atoms too, so that's what we understand. What else is there? Well if we were instead made of bits the paint would have to be digital...
 16 March 2013 03:24 PM
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jarathoon

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Whilst studying Mechanical Engineering in my youth one of the experiments we repeated was Joules experiment on the equivilence of heat and work.

However instead of using a weight falling in the earth's gravitational field to drive a paddle wheel to warm the water, we cheated and used an electric motor.

Potential energy seems to me to be as real as the electrical energy transported in (or in the Faraday-Maxwell view "outside") wires. One can be converted to the other (with some losses I admit), or both forms can be turned into heat, to raise the temperature of an insulated water tank.

(I didn't raise the issue of energy ultimately being quantised, in my original post as I am just refering to macroscopic physical theory here, even though the conservation of energy is central to quantum theory as well. I am just asking here if it is possible to develop a unified and consistent view of energy within macroscopic physical theory alone)

James Arathoon

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James Arathoon
 30 March 2013 11:09 AM
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acsinuk

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If you charge up a battery or capacitor then it has the potential to produce energy. But it is not until the current starts moving at right angles to the voltage that the energy will be produced. This can then be transformed into mechanical energy electromagnetically in the third right angular dimension.
Happy Easter
CliveS
 01 April 2013 06:58 PM
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jarathoon

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Originally posted by: acsinuk

If you charge up a battery or capacitor then it has the potential to produce energy.


If you charge up a battery or capacitor with what? Energy perhaps?

So your view becomes - a capacitor can "produce" energy on demand from its store of energy previously injected into it (in a way not descibed).

Actually if you connect an inductor together with a capacitor (previously charged) you can get an oscillating current system with transference between potential and kinetic energy. This is analogous to a mechanically oscillating system, such as a pendulum.

One different thing is that you can cool the electric circuit to near absolute zero to rid yourself of all (ohmic=frictional) resistance losses (just the radiative losses from the capacitor are left - which don't form part of the analogy unless you bring in talk of graviational waves or such like).

Most engineers I doubt would shy away from using the word "produce" as it might lead people to believe that a capacitor or battery can act as some sort of energy amplifier or energy portal to other dimensions (see below, re: string theory), with our current understanding of the first law of thermodynamics (conservation of energy) as burnt to a crisp in the process.

Originally posted by: acsinuk

But it is not until the current starts moving at right angles to the voltage that the energy will be produced.


I don't understand this sentence. I think you have so condensed what you wanted to say that you have ended up with an absurdity.

The "voltage" is a scalar quantity so doesn't really have a physical direction. Perhaps you are obliquely referring to its derivative with respect to time.

Originally posted by: acsinuk

This can then be transformed into mechanical energy electromagnetically in the third right angular dimension.


This sentence doesn't make any sense to me at all. Mechanical systems operate in three spatial dimensions. Actually these three real spatial dimensions tally exactly with the ones electrical engineers work with (as well as those Euclid imagined in Alexandria all those years ago).

Things can be a bit different for physicists though.

If you are a theoretical physicist who believes that the real world consists of 10 spatial dimensions (as used in some string theories), then there are in fact 120 different combinations of 3 engineering (spatial) dimensions or 720 different permutations of 3 engineering dimensions to choose from. As long as you don't change your choice part way through the calculation, and don't allow energy to leak in or out of our 3 engineering dimensions, everything will work out fine apparently.

However having all these extra dimensions (no matter how small they are) does raise the possibility that energy could be flowing in or out of the engineering world to (and from) this new "physical external world".

Actually there doesn't seem any experimental evidence that energy contained and trapped by the engineering dimensions of our sensory imaginations is either escaping or being added to by yet undiscovered forms of energy transference.

If it did the first law of thermodynamics would be falsified when applied to the 3 spatial dimensions in isolation.

All this is a massive relief (to me at least). For some reason my imagination (like my sensory appreciation of the real world) can't comprehend more than 3 spatial dimensions.

Going back to a previous post above by Falciferum, I will try and do a "What is Entropy?" post when I get time; because I believe that there are subtle (yet significant) differences between how engineers (and chemists) view entropy, compared with how physicists and information theorists view entropy. In fact, just like energy, I am not entirely sure anyone really understands what entropy is either!

James Arathoon

[PS: in the generalised co-ordinates used by those studying Hamiltonian and Lagrangian dynamics there is a classical relation between the number of dimensions used and the degrees of freedom in the problem studied. I am definitely not talking about dimensions defined in this sense.]


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James Arathoon
 09 April 2013 03:22 PM
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acsinuk

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James
My point is that electrical energy is not just a scalar quantity or even a vector quantity of movement it is a 3D volume quantity of plasma energy [ like an arc welder spark] that can be converted not only into heat but mechanical energy as well.
Enthalpy, I believe, describes the formation heat of a molecule and entropy somehow demonstrates the transfer of energy between molecules in different states. Solid to liquid to gas to plasma as the temperature increases over time.
CliveS
 09 April 2013 06:34 PM
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jarathoon

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Clive,

Your visual imagination is completely different to mine.

For me heat is mostly about matter in motion, atoms, molecules and groups of molecules in motion. The higher the average speed of the particles the higher the temperature, until the atoms ionise and a plasma is formed.

But is all the heat energy in a hot gas, kinetic energy. I think some engineers and physicists would answer yes to this, but this is true only if you ignore the short periods of time in which an atomic collision occurs or the short period of time when a gas atom bounces against the vessel wall. A gas doesn't seem to be a system where, at any particular moment in time, some proportion of the energy is held in the form of kinetic energy and some proportion potential energy; but it certainly js at the microscopic level.

Yet a gas allows sound waves to pass through it, which are reversible in a thermodynamic sense. Sound waves can also be modelled by considering that energy is changing from the kinetic form (motion) to a potential form.

So even within a gas, which at first sight appears devoid of potential energy (except at the very moment of each atomic collision) seems to become at the macroscopic scale a medium which can store potential energy (and kinetic) in a fully reversible way in the sound waves that exist at ALL length scales.

Here is where I part company with the physicists (and Maxwell for that matter - in modern terms he is very much more like an engineer). I really think we are missing something critical to our models. I don't believe that macroscopic potential energy (as stored by sound waves) can immerge from a gas model of colliding atoms, without some inherent potential energy being stored at all physical length scales of the gas volume (it could be a very small percentage of the overall heat energy stored).

One of the things that leads me to think that there is potential energy stored at all length scales in a gas is the phenomena of atmospheric tides. These are twice daily changes in atmospheric pressure which can be measured most easily at equatorial latitudes, and which are synched with the position of the sun alone (not the moon and the sun as with ocean tides). They are completely independent of the sort of pressure changes that might be ascribed to thermal forcing as the sun heats the ground say (because exactly the same semi-diurnal (twice daily) variations in pressure occur over sea and land).

The phenomena of atmospheric tides has nominally been explained due to thermal forcing of the high atmosphere transmitted down via a frequency doubling process. This seems to arise naturally from copious quantities of spherical harmonic equations and some dubious physics concerning accelerating frames. (see Chapman and Lindzen (1970) Atmospheric Tides)

Needless to say I don't accept their explanation, which is only marginally better than Lord Kelvin's original resonance explanation.

I suspect that there are small twice daily changes in the spring constant (or compressibility) of the air (and thus leading to small variations in the ratio of kinetic to potential energy stored in the air). One possible explanation for this is that atomic collisions vary very slightly in the length of time they take on average to "bounce", and this depends on the position of the sun in the sky.

The semi-diurnal pressure tides are too regular (i.e. unlike all other meteorological phenomena) to depend solely on the vagaries how the upper atmosphere heats up and cools down.

There you are then, my wild imagination is completely different to yours! Perhaps it is just nonsensical in a completely different way!

James Arathoon


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James Arathoon
 09 April 2013 07:41 PM
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jarathoon

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For a long time now I have been trying to determine the relationship between Newton's quantitaive theory of gravitation (as expounded in Principia) and his qualitative theory of graviation as described in the queries found in his book "Opticks" (see queries 20 and 21 for example)

I now believe Newton was thinking "mathematically" in his qualitative theory, as well as in his quantitative theory.

His quantitative theory relied on action at a distance, and his qualitative theory relied on action by contact, via some medium with a varying material density and with a large elastic constant. (Euler and Maxwell interpreted this as being a medium under hydrostatic pressure and I agree with him on this)

It seems to me that all you need to do is convert material density to energy density and ascribe energy density changes in the medium to variations in the elastic constant brought about by the pressence of mass, and Newton's qualitative ideas can be brought into line with his quantitative ideas.

The question that arises from studies of this type is this.

Is comparing Newton's qualitative theory with his quantitative theory one of the following?

a) philosophy
b) mathematics
c) physics
d) history
e) pedagogy
f) psychology

Or is it plain old engineering?

The above study is probably some complicated mixture of (a) through to (f).

Some complicated mixture of (a) through (f), is in itself a reasonably good description of the fields of knowledge engineers have to trample over in the course of their work.

Yes I think it is within the scope of engineering to consider questions such as that given above, even if the end results of such work later effect how people see and learn physics or indeed mathematics.

(Obviously engineering of biological systems is now part the equation - which didn't really exist in Newton's day - other than controlling horse power of course!).

James Arathoon

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James Arathoon
 09 April 2013 08:21 PM
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jarathoon

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I also have in mind that there is evidence that some radioactive substances can vary slightly in their decay rates over the course of a year more than others.

I also have in mind the fact that the moment of inertia of the earth changes inexplicably for a short time during and after a solar storm mass ejection event.

To me if all clocks changed in the same way (with the same time constant and having the same effective transfer function) under influence from the sun and its varying distance and storm levels, we shouldn't be able to "see" any of these effects, because all our "clocks" would vary in the same way.

So perhaps all these subtle variations in the "clock" rate of different time measurement systems is in some sense differential, based on the time constants and physics of the devices and systems themselves.

Perhaps some of our clock systems (including atomic clocks and pulsar clocks) are more or less independent of solar influence.

If all our clocks changed we would perhaps see this in yearly variations in the measured radiation energy fluxes from the sun and stars, and as far as I know this does not happen.

James Arathoon

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James Arathoon
 10 April 2013 08:08 PM
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Zuiko

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Well, you can eliminate potential energy because energy is movement, or the change of movement.

That is of course not correct. A body can have energy relative to another body purely because of it's position. This is called potential energy and it is a real quantity.

A simple thought experiment will prove to you that it is real.

Consider the axiom that energy cannot be created or destroyed.

Now consider a child on a swing, in motion going back and forth. At the top of her swing, her kinetic energy is exactly zero, because she is not moving, therefore 1/2 mv^2 = 0J because v = 0 m/s.

However, her potential energy is at a maximum,
ie mgh = max J because h = max


As she moves down (due to gravity) the total amount of energy in the system remains constant. But some of her potential energy is converted to kinetic energy. At some point through her descent her kinetic energy and potential energy are equal.

ie mgh = 1/2 mv^2

At the bottom of the swing, her velocity is maximum, so

1/2 mv^2 = max because v = max

Then the opposite happens in reverse and the kinetic energy is converted back to potential energy.


Consider also a hydroelectric storage dam. Energy is used to pump the water up to the dam. Some energy is lost in the pumping process (heat, noise, friction etc). But the rest of the energy remains in the water, at the top of the dam.

When the water is released, this energy is released. And the energy in the water is due to its position less the energy it took to get it there.
 13 April 2013 03:24 PM
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jarathoon

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Zuiko, Yes potential energy (PE) is just as real as kinetic energy (KE), but that might not be saying much if both measures of energy can be redefined relative to different inertial frames of reference. It appears we can transform away kinetic energy when we change our frame of reference, and hence redefine its baseline value. Its not clear we can do the same with gravitational potential energy or other forms of potential energy, but perhaps you can. So perhaps saying "potential energy (PE) is just as real as kinetic energy (KE)" is just the same as saying "potential energy (PE) is just as imaginary and relative a concept as kinetic energy (KE)" Also a lot of the energy we observe in the universe is in the form of an energy flux (e.g. Electromagnetic radiation) According to special relativity our in frame clocks will slow as our speed increases. This means that the integrated energy received from the remote stars per unit time (measured perpendicular to our direction of travel) will increase. It we integrate this starlight energy to make a clock, then it will tick at a faster and faster rate compared with our in frame clocks. Which way of measuring time is the right one? and does the way we measure time alter our view of whether energy is real or not? James Arathoon

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James Arathoon
 13 April 2013 04:54 PM
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westonpa

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Energy is just a name that we humans gave to something in order that we can each communicate with each other about it. Most people speak about energy in the classical physics realm, e.g., what they can see, feel, hear, measure, etc., but 'energy' starts in a place we cannot see, feel, hear, measure, etc., because we do not yet have the correct tools. People speak about chemical energy, potential energy, kinetic energy, nuclear energy, etc., etc., but 'energy' is all about movement because even if a body of water is built up behind a damn and appears to be still within it the atoms and/or the building blocks of atoms are moving. When the damn is opened the movement within and/or of the atoms simply add and/or change to a different type of movement. However even whilst that water is moving there will still also be internal movement within the atoms which make up the water and even when it comes to a rest the atoms, and that which makes them up, will still be moving. Everything which exists within the universe is real because even if we imagine something it is real because in the mind atoms/quarks etc., have 'communicated' with each other to create a memory. We humans are a product of the universe and its building blocks and the labels we attach to things are only to help our understanding and communication about it, but they do not change its building blocks or that it exists, unless of course we get spooky and think it's all some kind of dream and we have all been duped. Energy is real and energy is movement and if everything stopped moving down to the smallest particle then it is likely that there would be no energy as we would understand it. You strike a match and light a fire only because the atoms in your body move and allow that to happen.

If we ask the question of where did all this come from then it gets really interesting because that then raises other questions which we cannot answer at this time and maybe we never will.

Regards.
 15 April 2013 02:05 PM
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jarathoon

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I agree energy is real, but I am not sure that all forms of energy need be equated to movement, for example gravitational potential energy.

An extreme view on this is that not just gravity (explained by unobservable gravitons variants wizzing around the universe) but everything else can be explained by M-Theory [encompassing 11 dimensions of space and time]...

http://www.latimes.com/news/sc...30410,0,7704203.story

"
For him [Stephen Hawking], the answers to the largest and tiniest questions lie in M-theory.

"To understand the universe at the deepest level, we have to understand why is there something rather than nothing," Hawking said, speaking through a computer program that converts his eye and cheek movements into spoken speech. "Why do we exist? Why this particular set of laws, and not some other? I believe the answers to all of these things is M-theory."
"
Even though engineers do not really understand what energy really is, at least we are prepared to admit it.

The problem is a lot worse for the theoretical physicists. Some of them don't even admit the existence of the problem and some appear [like Hawking] to have completely given up on all logic and reason...

Perhaps Hawking should encourage engineers to work on M-Theory, because as we all remember the last notable English mathematical physicist (half swiss) was Dirac, who trained as an electrical engineer and as it turned out actually predicted things we could measure; and the most notable one before that was Oliver Heaviside, who really was an electrical engineer.

However I think engineers would write off M-Theory as a bad job within a few days of starting to study it.

James Arathoon

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James Arathoon
 15 April 2013 09:03 PM
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kengreen

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That is a very perceptive question.

It has long been my view that it is a relic of early experimenters trying to make sense of their discoveries. They most certainly may be forgiven for setting out on a false trail but, today, it is difficult to put the wagon back on the tracks.

The word is bandied about almost as a colloquialism without thought as to what its derivatives may actually mean. For example: settle back and write two definitions for (a) potential energy and (b) for kinetic energy. Make those definitions rigorous and you will find that they are identical.

We need to go back to the roots of our Physics and fill such holes as these.but be warned - you will be criticised for throwing out the baby with the bath-water.

And you will meet real trouble when you get around to rubbishing those cherished Black-holes and the zoo of multi-coloured particles.
kengreen
 15 April 2013 10:11 PM
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westonpa

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Originally posted by: jarathoon
I agree energy is real, but I am not sure that all forms of energy need be equated to movement, for example gravitational potential energy. An extreme view on this is that not just gravity (explained by unobservable gravitons variants wizzing around the universe) but everything else can be explained by M-Theory [encompassing 11 dimensions of space and time].

The thing about theories are they are just that, theories. We exist and there is something in which we exist and we are built from things which also exist. I can no more prove I am correct than you can prove I am incorrect and therefore what I suggest is just as possible to be correct as it is wrong. I do not subscribe to the thinking that just because the majority agree on something therefore it must be correct. If I am built from the building blocks of this thing in which we exist how do I know that I am not already programmed to see only what I am allowed to see? In my opinion energy is all about movement and different types of energy are simply different types of movement and we humans just use different words to make ourselves think we are clever. If you take some quarks and group them they make some atoms and if you take some atoms and group them they make some elements and if you take some elements and carry on grouping them you get some rocks and if you take some rocks and group them eventually you get some planets and if you keep going you get a galaxy and so on. All this 'new' stuff about dark energy is where we invent things to explain what cannot be explained and then we go look for some proof and then yahoo we find something which makes us feel comfortable that what we invented now seems true. I conclude that the cause of all that exists is unknown to us and whilst that remains the case many things remain possible.

Gravity may just be caused by particles so small that we have not yet found them.

Regards.

Edited: 15 April 2013 at 10:18 PM by westonpa
 16 April 2013 02:49 PM
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jarathoon

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Originally posted by: kengreen

That is a very perceptive question.

It has long been my view that it is a relic of early experimenters trying to make sense of their discoveries. They most certainly may be forgiven for setting out on a false trail but, today, it is difficult to put the wagon back on the tracks.

The word is bandied about almost as a colloquialism without thought as to what its derivatives may actually mean. For example: settle back and write two definitions for (a) potential energy and (b) for kinetic energy. Make those definitions rigorous and you will find that they are identical.

We need to go back to the roots of our Physics and fill such holes as these.but be warned - you will be criticised for throwing out the baby with the bath-water.

And you will meet real trouble when you get around to rubbishing those cherished Black-holes and the zoo of multi-coloured particles.

kengreen


Somehow we have developed a model of science which leads the best mathematical physicists to study theories which are unlikely to ever be experimentally verified one way or the other. And yet some vital subjects, for our collective future on this planet, such as solar terrestrial physics are left to languish.

e..g. The physics of clouds is in a terrible state [Mason's theory of drop growth needs to be replaced with something better].

One of my main gripes is that we still don't really know how the earth maintains its geomagnetic field.

http://en.wikipedia.org/wiki/Earth's_magnetic_field

We pretend to be able to explain it using some variation or other of a asymmetric dynamo, arising out of convection currents in the earths outer core. But this has always struck me and many other people as contrived and completely unrealistic.

However the earth has a solid core within the molten outer core (as shown by detailed seismic models of the earth when major earthquakes hit). The obvious answer is simply that the solid core rotates with a different angular velocity and with a different axis of rotation to the rest of the earth and what we really need is some new physics that explains how this differential rotation leads to the geomagnetic field.

There are lots and lots of dodgy theories in solar terrestrial physics, the field has been ripe for revolution for decades now. Yet are talented young mathematical physicists attracted to the field? No. They are attracted into saying more and more things about black holes that no observational astronomer is ever going to be able to verify.

I just get really annoyed by physicists saying M-theory is the route to all understanding, because it isn't.

Why should we continue to pay for large numbers of our most talented mathematical physicists to continue to work on things (throughout their whole careers) without experimental consequence when there is so much vital work to be done in realm of solar terrestrial physics say?

I invited John Moffat (author "Reinventing Gravity") over from Canada to speak at the IET last year, because I was disgusted that so many uk physicists with a media voice were ardent believers in dark matter, even though the stuff is completely invisible and nobody had ever observed any experimentally. Everyone towing the same speculative party line does not make for the sort of healthy pluralistic science culture that Britain has always been known for.

[Some experimentalists claim to have now found hints of dark matter

http://www.bbc.co.uk/news/science-environment-22155222

but other experimentalists say they don't find anything in the mass range specified.]

I don't think I am in danger of throwing the baby out with the bath water. Engineers need to think how we collectively save the baby [science] from drowning in the bath water [speculation without experimental consequence].

James Arathoon

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James Arathoon
 16 April 2013 03:47 PM
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rogerbryant

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I would recomend reading 'The Trouble with Physics' by Lee Smolin if you haven't already done so. He and Roger Penrose, 'The Emperors New Mind' both consider we are missing some very important point or points in our understanding of physics.

Best regards

Roger
 16 April 2013 05:33 PM
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acsinuk

Posts: 153
Joined: 30 June 2007

James
Energy is movement and can be measured in joules or Watt-seconds. A more practical unit is 3,600,000 times bigger and called a kWh. We imagine that it is a scalar quantity but in its not, as it must be contained in a volume of something which we can measure the temperature of. Energy should be measured practically in kWh per cubic metre. It is then easier to visualize how if you continue to add energy to a set volume that the PV=RT law will increase the gas temperature and how the other laws for temperature rise in solids and liquids of classical physics will apply.
CliveS
IET » Energy » What is Energy?

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