Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: F'dscience on 08/09/2017 07:16:56
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none scientist, or any science paper, has a clear, rational, precise definition of energy.
what is energy?
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All these fifty years of conscious brooding have brought me no nearer to the answer to the question, 'What are light quanta?' Nowadays every Tom, D i c k and Harry thinks he knows it, but he is mistaken. -Albert Einstein 1953
nowadays everything energy, everything quantum.
do you really know what is energy? not even einstein.
what is ENERGY?
coal? fuel? oxygen? wind? sunlight? any matters?
NO. matter is not energy. matter is the carrier/source/container of energy.
a rock at rest only has its thermal energy.
if you threw it away, your hand put a force on the rock pushing it moving at a speed v, the moving rock will have 1/2mvv energy added on it. we call it kinetic energy.
if the flying rock hits a wall, that energy becomes the impact force that hits the wall, makes atoms on the wall vibrate faster/hotter, atoms thermal energy.
so, energy is nothing but vibrating force/moving force.
energy is always vibrating/moving, within and between matters. matter is always moving/vibrating due to the existence of energy.
nothing is ever at rest, keep moving, changing, involving, reforming, transforming.
somehow, LIFE woke up?
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I think JP stated it best, he called it 'a coin of exchange'. It's something that connects everything we know of in thermodynamics. It doesn't go away, it just change state from something you can use to something that stops being useful.
http://www.auburn.edu/~smith01/notes/thermo1.htm
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All things have a very precise mechanism.
The sun is not shooting out light/em wave/photon/energy to every direction, it only shares its vibration em force with matters surround. the energy/force strength is proportional to sun's temperature and mass, inversely proportional to distance squared.
The sun's energy is from star formation, not from on going nuclear reaction.
The sun will never cool off a bit without other huge mass come closer.
To understand all this, must understand atom structure first.
for those believe our sun is a nuclear reactor, ask yourself few questions.
why does all the nuclear fuel not ignite at once?
how nuclear reaction produces heat/energy?
how the energy reaches earth?
if the sun has radiated out energy for 5 billion years, where is all that energy?
what is energy? moving force produced by moving mass?
without matter, there is no energy, no force, nothing. no us, no thought.
matter is made from charged particles.
opposite charged particles attract each other, they collide like magnet and iron ball. the impact force/energy becomes heat/thermal energy of the atoms.
the more atoms get together by gravity attraction, the more mass is added, the higher thermal energy density, the higher temperature.
so bigger star carries more energy, produces stronger light.
the energy is stored in vibrating atoms/charged particles.
the energy a star carry is the vibrating gravity and electrostatic force in its total mass/charges.
the sun's energy is from star formation, the sun is not an active nuclear reactor.
the energy cannot vanish into space but share with other matters surround according to their distance.
the sun's energy circling around earth as earth spins.
if energy can never leak/vanish into space, why all the fuels we used did not make earth warmer?
if you cut a channel between the ocean and a lake, the water level will be the same. if rained 1 foot into the lake, the water level will be still the same. the force between matters is the channel.
if rained 1 inch in the ocean, the lake will be flooded by i inch.
the sun's energy/vibrating electrostatic force/radiation stays within the upper atmosphere and moves around the earth.
transforming into smatter's movement, wind, clouds, waves,
photosynthesis and more.
we cannot create energy, all we can do is to use energy stored in fuels, in sunlight, and in moving matters.
forget about free energy, zero point energy, vacuum energy, magnetic energy generator.
solar, wind, tide, hydro are clean, renewable. low tech.
just $, cut space and war $, can we green the earth?
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You need to move that one to new theories. It's not really a answer to what you asked.
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If particles didn't have mass they would all travel at the speed of light c. Therefore a maximum momentum could be defined as mc. From this the rest energy naively becomes mc^2. Naive since this is a non relativistic term.
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The sun's energy is from star formation, not from on going nuclear reaction.
This is true of the Earth and Jupiter - there is internal heat from their initial formation (plus a bit of radioactive decay from Uranium, Potassium, etc).
This is true of objects even 15 - 60 times heavier than Jupiter - they are too small to achieve the pressures & temperatures necessary to achieve fusion of "normal" hydrogen = protons (although they might fuse any of the Deuterium & Lithium that occur in trace amounts in the universe).
These "failed" stars are called "brown dwarfs", because they never get hot enough to emit light and become "red dwarfs".
See: https://en.wikipedia.org/wiki/Brown_dwarf
why does all the nuclear fuel not ignite at once?
Because when you crush two protons together, their electrostatic force immediately pushes them apart again.
To get them to stick together (with the strong nuclear force), one of the protons has to turn into a neutron, almost simultaneously (via the weak nuclear force). Actions of the weak nuclear force are extremely improbable (compared to the strong force), and so proton-proton fusion occurs very slowly in stars the mass of the Sun.
In larger stars, Carbon, Nitrogen & Oxygen act as a "nuclear catalyst", which makes the Hydrogen fusion reactions go faster. This is thought to occur in stars more than 1.3 times the mass of the Sun.
how nuclear reaction produces heat/energy?
This article explains it better in pictures than I can in words:
https://en.wikipedia.org/wiki/Proton%E2%80%93proton_chain_reaction
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Back to the question, briefly:
Classical physics defines energy as one of the quantities that is conserved in all interactions. As is mass, momentum and angular momentum. Energy and mass are scalars, momentum and angular momentum are vectors.
Relativistic physics allows for the interchange of mass and energy with E = mc2 but in terms of everyday experience (apart from sunlight) we can usually ignore that interchange. Nevertheless, conservation still applies.
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none scientist, or any science paper, has a clear, rational, precise definition of energy.
what is energy?
At the upper limits of energy, photons will split into matter and anti-matter. If we take away the anti-matter and leave only matter, matter still exists at the upper limits of energy. Matter is at higher potential then energy. The direction of potential in our universe is matter to energy; via the forces of nature. In terms of reference, the potential also goes from inertial reference; matter, to speed of light reference energy, as matter lowers potential and releases energy.
Energy is the bridge between inertial references and the speed of light reference. Energy can be impacted by inertial reference; red shift, while also traveling at the speed of light where it exist in the C-reference. Energy is the bridge between inertial and C-level allowing matter to return to C-level.
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none scientist, or any science paper, has a clear, rational, precise definition of energy.
what is energy?
Damnit!
Have they forgotten?
There was a definition when I was at school- "Energy is the capacity to do work".
What happened to it?
Or does the OP just not know what they are talking about?
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Matter is at higher potential then energy. The direction of potential in our universe is matter to energy
It is thought that in the big bang, a lot of energy was in the form of quark-gluon plasma and other high-energy particles that we have trouble creating in the LHC. But as the universe cooled, energy precipitated out into the protons and electrons with which we are more familiar (plus dark matter, with which we are not nearly so familiar).
As they cooled further, the protons formed into deuterium and helium nuclei (plus a trace of lithium).
These then cooled further into the hydrogen and helium atoms that make up most of the Sun.
https://en.wikipedia.org/wiki/Chronology_of_the_universe
Why do you suggest that matter tends to turn into energy?
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"Energy is the capacity to do work"
I would say it is the full potential of the capacity of doing work.
And it is the curvature of spacetime. Now, try to define spacetime... If you take out spacetime from the Universe, what is left? Nothing! ???
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And it is the curvature of spacetime. Now, try to define spacetime.
Before you do that; define curvature of spacetime.
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And it is the curvature of spacetime. Now, try to define spacetime.
Before you do that; define curvature of spacetime.
The simplest answer I could think of is a curved trajectory in space through time without any net work done (or no net energy exchanged)...
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The simplest answer I could think of is a curve trajectory in space through time without any net work done (or no net energy exchanged)...
I'm not sure if you are saying that spacetime is actually curved, or not. If it is, it must be curved relative to something. What would that be?
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Relative to an inertial frame. A curved trajectory like the moon around the earth is a good example, if you neglect the losses. The moon orbiting the earth is in itself an inertial frame too... neglecting any net energy transfer, naturally (tidal, grav. wave, etc..).
This is a static limit. For a dynamical perspective, the energy is always in the curvature of spacetime anyway. At least, this is what I propose.
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I forgot to mention that if you added mass to the Earth (or energy) and the moon was still orbiting at the same distance from the Earth, it would mean that the curvature of spacetime is higher because the orbit cycle would be shorter and therefore there is more energy in the system. This is just to disambiguate space and spacetime.
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I'm not sure if you are saying that spacetime is actually curved, or not. If it is, it must be curved relative to something. What would that be?
Relative to an inertial frame.
Is it spacetime that is curved, or just a trajectory through an artificially inserted inertial frame in spacetime?
Chris Baird says this of spacetime curvature:
“In everyday language, we use the word "curved" to mean that a bar bends sideways in space away from a straight shape, or a ball traveling through space bends sideways in space away from a straight trajectory as it travels. When we talk about spacetime itself, the word "curved" must mean something else because spacetime itself can't bend sideways in space. A lot of popular writers speak sloppily in this way, but it really makes no sense. Spacetime is not a physical object sitting in spacetime, able to be grabbed and bent like a bar. Spacetime is the underlying universe itself”.
“I'll tell you a little trick that helps makes sense of spacetime. Any time spacetime is curved, it makes one direction act differently from the other directions. Put roughly, spacetime curvature makes one direction special. Anytime you have a reference frame where one direction is special, you have spacetime curvature. It is the curvature itself which makes one direction special”.
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In the same email from which the above quote came, Dr Baird also says: “A lot of popular writers speak sloppily in this way, but it really makes no sense”.
I found this in his blog:
“General Relativity describes how gravity is not really a direct, classical force. Rather, the effect we call gravity is simply how objects move in a spacetime that is itself curved”.
Hmmm! BTW, this is not a criticism of someone who has devoted quite a lot of time and effort helping me to sort out problems. I just thought I would mention it before someone else did. :)
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Yes, spacetime is not a substance in space but the fabric of the universe itself. I don't see any disagreement with what I said. But the truth is, to really understand gravity and spacetime, we need a unified theory.
Yesterday, I read a bit of a long discussion on another forum about the question of energy and motion. Someone suggested that energy is motion. Evidently, most answers were very negative. The standard model is stuck with a probabilistic model for quantum mechanics where particles have no definite trajectories. Someone even proclaimed that we can cool down particles to absolute zero creating a kind of static object. And then there is the alleged singularity at the center of a black hole... There is no point to argue with the defenders of the faith, especially when it is their job. Generally, they do a good job but their knowledge is just too limited and they just refuse to admit that they just ignore the definitive answer.
Seriously, it is obvious that everything is in a constant motion. And I'm ready to bet anything that energy is always in the motion and the curvature. In gunpowder, as in nuclear energy, in a coil spring or a magnet, the energy is just compactified in higher curvature. The gravitational redshift is equivalent to a redshift due to a relative velocity.
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In the same email from which the above quote came, Dr Baird also says: “A lot of popular writers speak sloppily in this way, but it really makes no sense”.
I found this in his blog:
“General Relativity describes how gravity is not really a direct, classical force. Rather, the effect we call gravity is simply how objects move in a spacetime that is itself curved”.
Another way to understand it is simply as I said: a curved trajectory without any net energy transferred can be seen as a straight line or a null path. The fact that the trajectory of a null path is curved mean that spacetime itself is curved... This is a uniform motion and therefore the object following this trajectory is an inertial observer. I think it helps a lot to understand it this way and it is how Einstein explained it.
My own point of view of space and time differs from the standard point of view concerning the basic ingredients. In my theory, there is no space, only a basic length (the Planck length). Space is a product of the basic length and time. Spacetime is relational to all elementary particles of the entire universe. Therefore, there is no pervasive spacetime forming a background; and spacetime is, in the end, the actual trajectories of particles. Then there are electric charges which are intersections between two different dimensions of spacetime, but this is another story. I try to avoid mixing my theory to this section of the forum. There are many unresolved concepts in Physics while a majority of physicists think they are well explained and well understood.
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Sascha Vongehr has some interesting comments on energy here:
http://www.science20.com/alpha_meme/energy_not_golden_holy_cow_urine-72881
"Classically, space-time is static, and so E is conserved, which means if some is missing, we better find out where it went. However, energy in general relativity is not even expected to be conserved. If it is missing and we know well why it is missing, then why not? Why be traditional?
If E is not conserved, then a perpetual motion machine becomes possible. Exactly! Did you guys not yet realize that the universe is a perpetual motion machine of the worst kind? It not just creates E, it creates space-time out of nothing, violates the second law of thermodynamics, all of it. And I ask again, why should it not? Certain “laws” are applicable when certain symmetries are present for the system under investigation. These symmetries that describe the physics in our backyard may not hold for the universe as a whole, and why should they? They should not even be expected to hold".
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If we are here to talk about this, it is because there is a basic asymmetry within the entire universe. This basic asymmetry could be motion and time itself. I don't think you can build a machine with a perpetual motion, because you would need to control the entire universe to do so. Being a part of it, it's kind of difficult :)...
It doesn't mean energy is not conserved. Energy is always conserved locally and in any local experiment. The fact that it is not conserved in GR is due to comparing frames that are out of sync. By including non locality, you can keep energy constant by taking only synchronized frames. GR is fuzzy... no synchronization and lost in space... Though it is great, it is incomplete.
I think physics needs simplifications and more and better explanations, including of unknowns. The basic laws must be very simple. Finding simplified explanations explaining more is the key toward success.
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CPT ArkAngel, there are a couple of points in your last post I'd like to return to, but in the meantime; some thought I was having while waiting for a Consultant appointment.
Thinking about energy, I found myself wondering how many types of energy there might be: or could it be that there is only one?
Three types came immediately to mind: Mass Energy, Kinetic Energy and Potential Energy.
Why?
Because they manifest clear differences. They seem to relate to distinct situations, and each is relevant to its specific situation.
That said; I think it could be argued that there is only kinetic energy.
Why?
Because Einstein said: "The mass of a body is a measure of its energy-content". This energy reflects atomic movement, so is, arguably, kinetic energy.
In the case of potential energy; the word “potential” implies that it is not actually energy, until it moves. Thus, it is potential kinetic energy.
Could it, therefore, be argued that all energy is, at a fundamental level, kinetic energy?
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First, it depends on how you define kinetic energy. Beyond Newton physics, kinetic energy has many labels and many forms.
I'm not entirely sure if I should say energy is "in the motion AND the curvature" or "in the motion AND/OR the curvature".
Time is not supposed to have a direction, it is a scalar. But what I think is Time has all directions in relations to the entire universe. For now, I see curvature and motion as equivalent in the same way inertial mass and gravitational mass are equivalent... It would be groundbreaking to find a single mechanism explaining all forms of stress energy and both gravitational and inertial masses!
But in the end, energy implies motion and motion implies curvature. An essential duality.
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But in the end, energy implies motion and motion implies curvature. An essential duality.
If energy implies motion, does that not imply that it is kinetic energy?
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I'm not entirely sure if I should say energy is "in the motion AND the curvature" or "in the motion AND/OR the curvature".
Wouldn't that depend on how the energy is held in the curvature? That's something I've been wondering about since I first met the statement: "The energy is held in the curvature".
Time is not supposed to have a direction,
I thought time was supposed to have a single direction.
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The force of gravity has a special direction. Towards the centre of the source mass. That is the curvature of spacetime. It is a gradient in the gravitational potential. It is what allows a circular orbit to be stable.
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There is still the possibility of half energy in motion and half in the curvature... Is there one coming first or they come in pair? Can you have more curvature while less motion and vice versa (or can they be out of phase)?
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There are various types of energy. Rest energy, equivalent to rest mass, kinetic energy, relativistic energy and potential energy. These are distinct. One type may affect another. Such as potential energy affecting kinetic energy. So it isn't just a case of portioning out energy so that some creates a curvature while another signifies motion. The study of tensors can be beneficial in understanding the mechanisms. This starts with a study of special relativity.
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BC the ability to do work is pretty nice, but what then about heat? The 'heat death of the universe' where the ability to do work no longer is possible. Would that then mean that this heat isn't a state containing energy?
I still like JP:s definition better. As a 'coin of exchange', although, thinking of it, the same might be asked there.
'Energy' is also something that people expect to be connected to 'time', as in the 'energy' of a vacuum being able to have no limit although then under such a short period of time that it becomes unmeasurable, if I now got that right :) I'll probably need to look it up, again ....
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I was talking about a theory in which particles have real and unique trajectories.
If you move up your keyboard, you increase its potential energy. But at the same time you increase its timerate, by the same token you increase its internal speed... The external speed would have an equivalence in the graviton rate of update.
I proposed an internal speed V1 and and external speed V2 where V1^2+V2^2 always equal C^2. This is special relativity.
All type of masses are MC^2... Newtonian kinetic energy is 1/2*MV^2.
But this is just a theory! I needed to give more explanations, sorry!
I think curvature and motion are always in phase and they can`t be separated but I could be wrong. There are no explanation of internal mechanisms for energy nor time within elementary particles in the standard model.
In GR, Time has a direction from the past to present and to the future but it has no direction in space. Past, present and future coexist because there is no synchronization in GR.