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Does the sun release stored energy?


MarkE

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I think that the answer should be 'NO'. This is my explanation:

The arrangement of atoms in a molecule can store energy. The same atoms, arranged differently, may hold less energy. It takes energy to hold a bond together, so by breaking it, you’re releasing the energy that held it together. Heat/fire therefore is the breaking of a formation and/or bond, just like glucose, oil (alkanes), ATP, they’re all ‘balls on top of a hill’ so to speak. (Why THIS arrangement has that feature, and not some other arrangement, is also quite interesting to me).

The sun releases energy in the form of gamma rays by fusing hydrogen atoms together. Does this mean that the element hydrogen conserves energy, just like glucose, oil, or ATP? That would mean that the arrangement ‘hydrogen’ is potential energy by itself? (I’m referring to ‘hydrogen’, not just to a ‘proton’, because it’s not just the protons that, by fusing together, create gamma rays, but also the electrons, that cancel out with the positrons together release gamma rays). Hydrogen is of course a 'bond' of 2 subatomic particles, a proton and an electron, but protons tend to repel each other, because they are charged +1, so fusing them together can’t be a natural reaction, it doesn't seem to be in accordance with the thermodynamic law of entropy.

Radioactive decay on earth take place by neutrons becoming protons, without any external input, that releases stored energy, right? This reactions happens naturally, obeying the law of entropy, because (subatomic) arrangements can’t become more organised just by themselves, they tend to become less organised instead.

The sun is changing its hydrogen atoms into combinations of proton-neutron elements (first deuterium, later higher elements numbers), and by doing that release energy. But how? This can't be stored potential energy, right? If this is an opposite reaction (compared to radioactive decay on earth), you would need an energetic input to make those protons fuse together, but... where does this input come from?

Edited by MarkE
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Mass of proton is 938.272 MeV/c^2

[math]p^+ + p^+ \rightarrow D^+ + e^+ + v_e + 0.420 MeV[/math]

Where does this 420 keV come from?

It's difference between mass-energy of Deuterium nucleus and two protons.

On the left equation you have 2 mp, on the right mass of Deuterium, mass of positron-electron and energy released in the reaction:

[math]m_p c^2 + m_p c^2 = m_d c^2 + m_e c^2 + 0.420 MeV[/math]

[math]938.272 MeV + 938.272 MeV = E_d + 0.511 MeV + 0.420 MeV[/math]

Rearrange it:

[math]E_d = 938.272 MeV + 938.272 MeV - ( 0.511 MeV + 0.420 MeV )[/math]

[math]E_d = 1875.613 MeV[/math]

[math]m_d = 1875.613 MeV/c^2[/math]

 

1u = 931.494 MeV/c^2

[math]m_d = \frac{1875.613 MeV/c^2}{931.494 MeV/c^2} = 2.01355 u[/math]

Add mass of electron, and there will be ~ 2.0141 u.

 

Edited by Sensei
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12 minutes ago, MarkE said:

I think that the answer should be 'NO'. This is my explanation:

The arrangement of atoms in a molecule can store energy. The same atoms, arranged differently, may hold less energy.

Molecular arrangements do not "store" energy. Energy is released when bonds form. A molecule has less energy than the free atoms which comprise it would have.

Chemical and nuclear reactions release energy when they form systems that are more tightly bound. 

12 minutes ago, MarkE said:

It takes energy to hold a bond together, so by breaking it, you’re releasing the energy that held it together.

The opposite is true.

12 minutes ago, MarkE said:

 The sun releases energy in the form of gamma rays by fusing hydrogen atoms together. Does this mean that the element hydrogen conserves energy, just like glucose, oil, or ATP? That would mean that the arrangement ‘hydrogen’ is potential energy by itself? (I’m referring to ‘hydrogen’, not just to a ‘proton’, because it’s not just the protons that, by fusing together, create gamma rays, but also the electrons, that cancel out with the positrons together release gamma rays). Hydrogen is of course a 'bond' of 2 subatomic particles, a proton and an electron, but protons tend to repel each other, because they are charged +1, so fusing them together can’t be a natural reaction, it doesn't seem to be in accordance with the thermodynamic law of entropy.

The electrons are peripheral to the main interaction, which is the fusion of protons.

12 minutes ago, MarkE said:

Radioactive decay on earth take place by neutrons becoming protons, without any external input, that releases stored energy, right? This reactions happens naturally, obeying the law of entropy, because (subatomic) arrangements can’t become more organised just by themselves, they tend to become less organised instead.

Alpha decay, too. And you are misapplying entropy. 

12 minutes ago, MarkE said:

The sun is changing its hydrogen atoms into combinations of proton-neutron elements (first deuterium, later higher elements numbers), and by doing that release energy. But how? This can't be stored potential energy, right? If this is an opposite reaction (compared to radioactive decay on earth), you would need an energetic input to make those protons fuse together, but... where does this input come from?

The energy needed is simply an activation energy — a threshold that must be overcome (the Coulomb barrier). It is present owing to the high temperature.  The stored energy is in the mass of the particles.

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22 minutes ago, MarkE said:

where does this input come from?

Here is a simpler summary of one of our models that best moves on from what you already seem to know.

Yes potential energy is stored in the arrangement of atoms within a molecule.

This energy is electrostatic in nature as is the force that generates it.

You are right in observing that this force opposes the cramming together of like charges as we find in the nucleus.

So there must be other forces involved and your question seems to be about what these are.
Furthermore these forces must be stronger than the electrostatic ones.

 

We identify four what are called fundamental forces.

1)Gravity

2)The electromagentic force

3)The strong nuclear force

4) The weak nuclear force

All four lead to a potential which can be regarded as an energy store.

Early physicists discovered that the strengths of forces (1) and (2) vary with distance, the stength falling away as distance increases.
They also found that the electromagnetic force is many orders of magnitude greater than the gravitational one.

When physicists asked the very questions you are now asking they realised that the forces holding the nucleus together must be very short range compared to the first two.
So these forces really only act within the atom.

 

So just like the arrangement of atoms in a molecule, the arrangement of sub atomic particles in an atom can be regarded as storing energy in the potential fields of (3) and (4).
As already noted the internal electrostatic field within the atomis small by comaprison .

This energy is known as binding energy.

Now observation has shown that the binding energy per nucleon varies with each atom.
This is shown by what is known as the packing fraction curve.

And this is interesting because this curve has a minimum at atomic number 56 (iron).

This means that if nuclei smaller than iron are combined energy could be released until the resulting combined nucleus is that of iron.
We call this fusion.

Equally nuclei larger than iron can release energy by breaking apart to move towards nuclei of the size of iron.
We call this fission.

As you say there is a thermodynamic imperative for this, but it is due to energy not entropy.
As with all thermodynamic calculations we work this out by adding up the sum of all the potentials of all the species before the process and comparing that with a similar sum for the species after.
This is how fission can release much smaller particles than iron as well. There is a net energy release.

As a matter of interest, I think but I am not sure, that our Sun is not hot enough for even helium to fuse, that happens in a nova.

And to get all the way from hydrogen to iron to need a supernova.

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7 minutes ago, MarkE said:

The answer should be 'YES' then?

The answer should be that I have given you some new terms for you to look into.

There is a more modern explanation in particle physics, without forces at all, that Swansont and Sensei are offering, but this is a good route there, following the historical development of the subject.

Edited by studiot
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One could argue that it is Gravitational potential which provides the unrelenting compression for the H and He nuclei. This compression gives temps and pressures at the Sun's center to fuse H ( and even He nuclei Studiot ) into heavier and heavier elements. When sufficient radiation pressure is produced by the various fusion reactions, the Sun 9 or any star ) is in equilibrium ( somewhat ) and will stay that way for millions or billions of years ( depending on its size and composition ). When heavier elements ( approaching atomic number 26 ) are produced by the fusion process, it is less and less efficient, and eventually n iron core results in a brown/white dwarf star.

In the case where the star is really massive, the nova/supernova process injects energy back into the core ( also gravitational ) and produces heavier elements above iron ( atomic number greater than 26 ). The shock waves from the nova blasts also compress interstellar gases ( mostly H, various amounts of He, and heavier elements ) to create new stars.

So you could say that, far from being the weakest force, Gravity is the one that makes everything happen.

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@studiot Thanks for your answer, well, everybody thanks for your explanations, but I'm concentrating only on your reaction here, because otherwise it's too much at once.

You're saying something about 'packing fraction'. I understand now that because of this, sometimes fusion can release energy, and sometimes fission instead (after Iron-56). In our sun, 4 protons are turned into 1 Helium atom + energy. This Helium atom has less mass than those 4 protons together because there's less total binding energy involved in Helium. This difference is exactly the energy that has been released (gamma rays, positron and neutrino). Does this by the way mean that our sun is becoming lighter and lighter?

I have a pretty hard time understanding this 'electrostatic energy'. How can heat energy be static? 'Energy', sure, gravitational potential energy, but 'heat energy'? Heat, radiation, is constantly moving, that's why it's called heat, because a particle is moving, the faster the hotter, so how could heat energy be static (not moving), and reside anywhere in the first place? Gravitational energy it's the path that 'stuff' can fall to increase its own movement, like a ball falling from a hill, but empty space (like the space in between the ball and the floor) could never be heat by itself, right? That wouldn't make sense. The space between a hill and a ball on top of it has no energy by itself, only the ball has mass, and therefore energy, because it's made of 'stuff'. But the way I (wrongfully, I hope) understand molecules like glucose, alkanes or ATP is that heat can be stored in a field, poof, gone, and than can be called up (like a genie in a bottle) to show up out of this 'field' where it was hidden from reality. I mean, a ball has to stay a physical ball in order to ever roll down. I have a really hard time understanding a quantum field if it would imply that, at the quantum level, this somehow is totally different from a ball on a hill, because somehow a quantum ball could actually disappear, into a field, where it 'resides', and still be heat energy. it doesn't make any sense (to me). Or is it just that, in these molecules, electrons are in a different shell that explains the difference?

I really hope that, concerning these three molecule examples I just gave, just like in the sun, measuring the difference in binding energy explains where the heat went, just by rearranging itself, without disappearing from the real world or something like that. I really hope that the quantum world is understandable ;)

Edited by MarkE
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3 hours ago, MarkE said:

@studiot Thanks for your answer, well, everybody thanks for your explanations, but I'm concentrating only on your reaction here, because otherwise it's too much at once.

You're saying something about 'packing fraction'. I understand now that because of this, sometimes fusion can release energy, and sometimes fission instead (after Iron-56). In our sun, 4 protons are turned into 1 Helium atom + energy. This Helium atom has less mass than those 4 protons together because there's less total binding energy involved in Helium. This difference is exactly the energy that has been released (gamma rays, positron and neutrino). Does this by the way mean that our sun is becoming lighter and lighter?

More. Binding energy is energy that's released in forming the bonds. It represents energy the system doesn't have anymore, and is the energy you'd need to add to break it apart.

Yes, the sun is lighter. It loses something like 4 billion kg each second (a negligible amount compared to the total mass of 2 x 10^30 kg)

Quote

I have a pretty hard time understanding this 'electrostatic energy'. How can heat energy be static?

It's not. heat is energy transferred owing to a temperature difference.

Quote

'Energy', sure, gravitational potential energy, but 'heat energy'? Heat, radiation, is constantly moving, that's why it's called heat, because a particle is moving, the faster the hotter, so how could heat energy be static (not moving), and reside anywhere in the first place?

studiot didn't discuss heat, from what I see.

Quote

  I really hope that, concerning these three molecule examples I just gave, just like in the sun, measuring the difference in binding energy explains where the heat went, just by rearranging itself, without disappearing from the real world or something like that. I really hope that the quantum world is understandable ;)

Heat from the sun is radiated to us in the form of photons. Energy doesn't just disappear.

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7 hours ago, MarkE said:

@studiot Thanks for your answer, well, everybody thanks for your explanations, but I'm concentrating only on your reaction here, because otherwise it's too much at once.

You're saying something about 'packing fraction'. I understand now that because of this, sometimes fusion can release energy, and sometimes fission instead (after Iron-56). In our sun, 4 protons are turned into 1 Helium atom + energy. This Helium atom has less mass than those 4 protons together because there's less total binding energy involved in Helium. This difference is exactly the energy that has been released (gamma rays, positron and neutrino). Does this by the way mean that our sun is becoming lighter and lighter?

I have a pretty hard time understanding this 'electrostatic energy'. How can heat energy be static? 'Energy', sure, gravitational potential energy, but 'heat energy'? Heat, radiation, is constantly moving, that's why it's called heat, because a particle is moving, the faster the hotter, so how could heat energy be static (not moving), and reside anywhere in the first place? Gravitational energy it's the path that 'stuff' can fall to increase its own movement, like a ball falling from a hill, but empty space (like the space in between the ball and the floor) could never be heat by itself, right? That wouldn't make sense. The space between a hill and a ball on top of it has no energy by itself, only the ball has mass, and therefore energy, because it's made of 'stuff'. But the way I (wrongfully, I hope) understand molecules like glucose, alkanes or ATP is that heat can be stored in a field, poof, gone, and than can be called up (like a genie in a bottle) to show up out of this 'field' where it was hidden from reality. I mean, a ball has to stay a physical ball in order to ever roll down. I have a really hard time understanding a quantum field if it would imply that, at the quantum level, this somehow is totally different from a ball on a hill, because somehow a quantum ball could actually disappear, into a field, where it 'resides', and still be heat energy. it doesn't make any sense (to me). Or is it just that, in these molecules, electrons are in a different shell that explains the difference?

I really hope that, concerning these three molecule examples I just gave, just like in the sun, measuring the difference in binding energy explains where the heat went, just by rearranging itself, without disappearing from the real world or something like that. I really hope that the quantum world is understandable ;)

I think we need to look more closely at some of the words you are throwing about.
This is because although these words are derived from English they have particularly tightly defined meanings in Science which are quite restricted compared to their general English usage.

So to start with a region of space.
This is pretty much the same as its English counterpart and might be the inside of an eggshell or a smartie box.
More usefully in Science it might be the bore of a pipe or the interior of a chemical reaction flask.
Or of course it could be the whole of space itself or just the space around planet where the panetary gravity is not negligable.

Whatever region we take it, we need a boundary to describe what lies inside the region and what lies outside.
Proper specification of that boundary is of vital importance in Science, particularly Thermodynamics - the Science of Heat.
We also identify  every individual location or point within the region. Some of these have special names such as the centre of gravity.

Another English word with a special meaning in Science is the word Field.

In English it often means 'the stage in which the activity takes place' eg the 'field of operations', 'he was an expert in his field' and so on.

This meaning is not taken on by Science, so do not use it in a scientific manner.

In Science a Field is a region of space where every point of that region has a specific value of some property of interest assigned to it.
Every point might have the same value eg the density in a homogeneous substance, or the pressure inside a small balloon.

So we can talk of a density field or a pressure field
Or the value may be different at every point for example the temperature field within a large copper bar, heated at one end with a blowtorch.

The properties of that Field as a whole will depend upon the particular property we are considering.
Some of these properties as simple numbers like in my examples, some are much more complicated mathematical expressions, such as the electric field vector in an electric field or the magnetic field vector in a magnetic field.

But there may be many properties and other things (like machinery or electric fires) inside a region.
In themodynamics we call such a region a 'system' and we include, but separately identify, the boundary.

These concepts allow us to develop conservation laws.

Conservation of mass, conservation of momentum, conservation of energy.

OK, so I used the E word - Energy.

For the moment, I will simply observe that there is only one property called 'energy' that has many forms that are all equivalent and stop there to allow you to digest this lot and ask any questions.

 

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I couldn't have explained the above better, excellent quality post.

 Useful hint non uniform field values gives rise to work potential, binding energy resists these changes so is also involves work.

energy is the ability to perform work

Edited by Mordred
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Thanks! It's important to set the different terminologies and concepts themselves right first, @studiot.

If I understand correctly, energy doesn't just 'disappear' into a field (of course!) because energy is always being conserved, which can be proven by measuring the binding energy, and heat that has been 'lost'. There's no 'hidden field' in QFD whatsoever (fortunately!), and everything is perfectly measurable. This binding energy can be high or low, if differs from the bond itself, one bond can be stronger than the other. That makes perfect sense.

An electron bound to a proton (a hydrogen atom) has slightly less mass than a free electron and a free proton. When the electron becomes bound to the proton, a photon is emitted, and the hydrogen atom becomes more massive because of this photon. But… a photon has no mass. So how can this photon itself be responsible for the mass change, according to E=mc2? 

Edited by MarkE
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10 minutes ago, MarkE said:

But… a photon has no mass. So how can this photon itself be responsible for the mass change, according to E=mc2? 

The photon has energy. That energy is equivalent to the mass difference (as described by that equation).

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24 minutes ago, MarkE said:

Thanks! It's important to set the different terminologies and concepts themselves right first, @studiot.

If I understand correctly, energy doesn't just 'disappear' into a field (of course!) because energy is always being conserved, which can be proven by measuring the binding energy, and heat that has been 'lost'. There's no 'hidden field' in QFD whatsoever (fortunately!), and everything is perfectly measurable. This binding energy can be high or low, if differs from the bond itself, one bond can be stronger than the other. That makes perfect sense.

An electron bound to a proton (a hydrogen atom) has slightly less mass than a free electron and a free proton. When the electron becomes bound to the proton, a photon is emitted, and the hydrogen atom becomes more massive because of this photon. But… a photon has no mass. So how can this photon itself be responsible for the mass change, according to E=mc2? 

Hopefully you have spent (some of) the last seven days reading and fleshing out my last post?

I am not a little surprised that you have no questions as a result of that post.

And also a little disappointed that you have just ploughed straight on with your use of the word Field as though I my post had never been written.

The whole point of that post was to avoid the misunderstanding you seem to have about a Field, since you seem to treat one as though it was some form of mystic substance that emanates from the end of a magician's wand.

The other trap to avoid is to try to 'pick 'n mix' topics from classical and modern Physics.
It is best to stick with one or the other and employ whichever gives the most convenient and closest match with observation.

In general modern Physics applies at very high velocities and /or very small sizes.

You have asked about stored energy ( a classical concept) and the Sun ( very large object)

So which would you think applies here?

 

Energy in particular is a classical concept so you need to fully understand classical energy before moving on to any modern application.

Edited by studiot
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29 minutes ago, studiot said:

Hopefully you have spent (some of) the last seven days reading and fleshing out my last post?

I am not a little surprised that you have no questions as a result of that post.

And also a little disappointed that you have just ploughed straight on with your use of the word Field as though I my post had never been written.

The whole point of that post was to avoid the misunderstanding you seem to have about a Field, since you seem to treat one as though it was some form of mystic substance that emanates from the end of a magician's wand.

The other trap to avoid is to try to 'pick 'n mix' topics from classical and modern Physics.
It is best to stick with one or the other and employ whichever gives the most convenient and closest match with observation.

It was my misinterpretation, somebody else explained it to me this way, a wrong way now it seems, that made it look like heat energy could actually reside somewhere, unmoving, in this 'field', which can't be seen/detected/measured because it's magically 'hiding' in this field. So thanks again for explaining to me that this is not the case. I know that the quantum world is a strange world, but this would be a little bit too strange!

Every particle has a field, but, have they ever been proven to exist outside of theoretical/mathematical models? Does nature actually creates these fields? 

35 minutes ago, Strange said:

The photon has energy. That energy is equivalent to the mass difference (as described by that equation).

The fact that a photon's energy is equal to mass, but at the same time it's the Higgs boson that gives mass to all particles in the Higgs field, is still very hard for me to understand.

Edited by MarkE
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1 hour ago, MarkE said:

 An electron bound to a proton (a hydrogen atom) has slightly less mass than a free electron and a free proton. When the electron becomes bound to the proton, a photon is emitted, and the hydrogen atom becomes more massive because of this photon. But… a photon has no mass. So how can this photon itself be responsible for the mass change, according to E=mc2? 

Less massive. You had it correct in the first sentence.

The photon energy was converted from the mass energy of the electron-proton system.

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1 hour ago, MarkE said:

The fact that a photon's energy is equal to mass, but at the same time it's the Higgs boson that gives mass to all particles in the Higgs field, is still very hard for me to understand.

Mass and energy can be converted into one another. That is a completely separate issue of how (some of) the mass of particles comes from the Higgs mechanism.

As a not very good analogy, I can change my money into goods (or goods back into money). That is separate from where my money comes from.

1 hour ago, MarkE said:

Every particle has a field, but, have they ever been proven to exist outside of theoretical/mathematical models?

I don't think anything in science is proven to really exist. But it may be better to think of it the other way round: there are fields and the particles we detect are "disturbances" or perturbations in the field. (There was a thread called "everything is fields", or similar, that discussed this is in more detail a while ago.)

As far as we can tell, our experiments behave in ways predicted by those fields. Whether they have a physical existence or are a convenient mathematical description of some other reality is unknown. (And perhaps unknowable.)

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2 hours ago, MarkE said:

An electron bound to a proton (a hydrogen atom) has slightly less mass than a free electron and a free proton. When the electron becomes bound to the proton, a photon is emitted, and the hydrogen atom becomes more massive because of this photon. But… a photon has no mass. So how can this photon itself be responsible for the mass change, according to E=mc2?

For many modern scientists word mass is equal to rest-mass. Charged particle, or complex particle made of few sub-atomic charged particles (overall neutral), can be put to rest, and rest-mass is measured.

Relativistic-mass of positron and proton (or muon+) can be the same (and their electric charge is the same), but their kinetic energies, velocities, Lorentz factors are different.

 

Photon is detected when it's absorbed by matter. Then it's momentum and energy influence matter that absorbed it. Total energy of system is increased. Then it can be emitted back to environment, or bunch of photons with lower energies instead.

 

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