Does e=mc2 violate thermodynamics?

[Dustin Kesselberg]

Essentially, yes. When you look at the mass and energy involved in high energy interractions you will notice that some of the mass has gone missing and energy has been emitted. Thats E= mc2 in action.

I though energy was the ability to do work.

Well if it has "gone missing" it's been destroyed and turned into energy,Which violates thermodynamic laws.They state that the amount of energy AND matter in the universe are always constant. This means that the money in the bank and pocket anology does not work.

The question here is....You have 10 dollars in your pocket and 100 in the bank.
The amount of money in your pocket stays constant as does the amount in the bank.
So how can you "convert" the two?


Also...."do work" means Move matter.

 

[Dustin Kesselberg]

It changes to energy - see the sun or nuclear weapons for examples.

"Changing" to energy from matter means that the amount of matter in the universe has just gone down while the energy gone up.This vilolates the laws of thermodynamics.
Also,Since "Energy" is just the ability to do work(non physical) how can it turn into matter(Physical) ?

Please provide a better explanation.

 

[Darat]

Well if it has "gone missing" it's been destroyed and turned into energy,Which violates thermodynamic laws.They state that the amount of energy AND matter in the universe are always constant. This means that the money in the bank and pocket anology does not work.
...snip...

No because it is now accepted (because of e=mc²) that energy and matter are just two different but equivalent ways of describing the universe.

...snip...

Also...."do work" means Move matter.

You can use energy to "do work" on other energy. Again don't forget we are trying to translate maths into English and have to be careful not to allow English (semantics) to confuse the matter.

 

[NarrMaster]

"matter and energy cannot be created nor destroyed" does not mean "matter cannot be created nor destroyed" and "energy cannot be created nor destroyed".

It is not two statements rolled into one. It is one statement, concerning the non creation/destruction of matter and energy, or more appropriately, matter/energy (because they can be converted).

 

[Dustin Kesselberg]

No because it is now accepted (because of e=mc²) that energy and matter are just two different but equivalent ways of describing the universe.

...snip...



You can use energy to "do work" on other energy. Again don't forget we are trying to translate maths into English and have to be careful not to allow English (semantics) to confuse the matter.

How can energy do work on other energy when energy is described as anything that can do work on matter?

Give me an Example.

 

[Brian the Snail]

Something does not seem right here...You seem to be saying that conversion of energy to mass and vise versa does go against thermodynamic laws.
But this does not seem right...Since the laws remain the same,Obviously it does not otherwise it WOULD of been amanded.

They have been amended. It's just that the conversion between mass and energy in most circumstances where thermodynamics is used (for example, chemical reactions) is so small that for all intents and purposes these kinds of subtleties can be ignored.

Also...Does the thermodynamic laws take place only in classical mechanics? And not quantum mechanics? Or what?

Thermodynamics is really useful for classical (i.e. large scale) systems. They can also be used for quantum systems as long as you consider long enough times/big enough systems. But to really understand why you need to understand quantum mechanics and statistical mechanics.

Im missing something here...I just don't know what. Because I know energy can't be created or destroyed. and I know that "converting" the two would cause one or the other to be created or destroyed.

Energy can be created or destroyed, by converting to and from mass.

 

[Dustin Kesselberg]

"matter and energy cannot be created nor destroyed" does not mean "matter cannot be created nor destroyed" and "energy cannot be created nor destroyed".

It is not two statements rolled into one. It is one statement, concerning the non creation/destruction of matter and energy, or more appropriately, matter/energy (because they can be converted).

1st law of thermodynamics="Energy cannot be created or destroyed, only modified in form."

The Law of Conservation of Matter="Matter cannot be created nor destroyed, only modified in form."

 

[MRC_Hans]

No offence meant, but this kind of questions always puzzle me.

Now, the sharpest brains on the planet have been working with this for the best part of a century; if it was fundamentally flawed, or logically inconsistent, don't you think somebody would have noticed?

Hans

 

[Badly Shaved Monkey]

I'll add my non-physicist's tuppence-worth to reiterate what Soapy just said. Once you can get to grips with mass and energy being two ways of expressing the same thing, there ceases to be a problem.

One thing I found helpful was to stop reading E=mc² as "E equals m c squared" and actually say, "E is m c squared". I find that gets the identity of them across in a subjective way more strongly.

Then focus on an example: I charge a NiCd battery and electrical energy enters it. Does that mean it is heavier? That seems to be ridiculous, but it is true, it's just that the extra weight conferred by giving it that electrical potential energy is really really tiny, because E must be divided by c² to express it in everyday units.

Or, you could say that my mass is 75kg, or you could adjust your bathroom scales to read in Joules, except the number would always be an unwieldy large one for reporting at WeightWatchers' meetings. "Today, Marcie, I weigh 64 times 10 to the 17th Joules"

(Edited for clarity)

 

[Dustin Kesselberg]

They have been amended. It's just that the conversion between mass and energy in most circumstances where thermodynamics is used (for example, chemical reactions) is so small that for all intents and purposes these kinds of subtleties can be ignored.

How is an Atomic Bomb a small scale?

Energy can be created or destroyed, by converting to and from mass.

This goes against the the first law of thermodynamics.

Also...Define "energy" in terms other than some objectification of matter acting on other matter.

 

[Badly Shaved Monkey]

How is an Atomic Bomb a small scale?

See my post with the example of the battery.

 

[Dustin Kesselberg]

No offence meant, but this kind of questions always puzzle me.

Now, the sharpest brains on the planet have been working with this for the best part of a century; if it was fundamentally flawed, or logically inconsistent, don't you think somebody would have noticed?

Hans

Im not saying it is flawed...Im saying how I am looking at(based on reading of physics) it seems flawed to me.


If Energy(as defined by every physics book i've read) Is just the ability to do work(move matter).

and The laws of thermodynamics are true.

Then E=mc2 can't mean that energy can be CONVERTED into matter and vise versa...

What does "converted" really Mean? Because It can't mean the energy destroyed and matter created because that violates thermodynamic laws.

I know that it takes tons of energy to split an atom and create energy out of it....But Still,Matter is being destroyed which violates thermodynamic laws.

It also takes tons of energy to collide particles to create matter but still you are substituing energy(destroyed) for matter(created).

 

[Dustin Kesselberg]

I'll add my non-physicist's tuppence-worth to reiterate what Soapy just said. Once you can get to grips with mass and energy being two ways of expressing the same thing, there ceases to be a problem.

One thing I found helpful was to stop reading E=mc² as "E equals m c squared" and actually say, "E is m c squared". I find that gets the identity of them across in a subjective way more strongly.

Then focus on an example: I charge a NiCd battery and electrical energy enters it. Does that mean it is heavier? That seems to be ridiculous, but it is true, it's just that the extra weight conferred by giving it that electrical potential energy is really really tiny, because E must be divided by c² to express it in everyday units.

Or, you could say that my mass is 75kg, or you could adjust your bathroom scales to read in Joules, except the number would always be an unwieldy large one for reporting at WeightWatchers' meetings. "Today, Marcie, I weigh 64 times 10 to the 17th Joules"

(Edited for clarity)

This really does not clear a thing up..

First of all...I do already see e=mc2 as e is mc2.

Second of all...If you charge a battery with electrical charge,You are sending electricty into it(Electromagnetic wave) which consists of particles..Which Im not sure,But I think they have weight. So electricty is not 100% energy since it contains particles which of course is matter. Which likely weighs something.

A better example would be sound waves...Do sound waves weigh any thing? No,They theirselfs do not...Their medium however does. And a "sound wave" is just like a ocean wave as in the energy of the ocean wave would not exist without a medium or matter(water).

 

[Darat]

This really does not clear a thing up..

First of all...I do already see e=mc2 as e is mc2.

What's your confusion then? Simple replace any use of the word "matter" and energy with "e=mc²" and use that as your label for whatever matter and energy "is".

Second of all...If you charge a battery with electrical charge,You are sending electricty into it(Electromagnetic wave) which consists of particles..Which Im not sure,But I think they have weight. So electricty is not 100% energy since it contains particles which of course is matter. Which likely weighs something.


A better example would be sound waves...Do sound waves weigh any thing? No,They theirselfs do not...Their medium however does. And a "sound wave" is just like a ocean wave as in the energy of the ocean wave would not exist without a medium or matter(water).

I am not being impolite here but perhaps you would be better working your way through some basic physic text books? I'm not that educated in physics and am not a great teacher but I can see from your above post that you are very confused or ignorant about a lot of basic theories and concepts of physics.



(Edited for formatting.)

 

[Pragmatist]

I don't believe the equation E=mc² violates any law of thermodynamics.

But there is an issue here that needs to be addressed and which I think is being widely misinterpreted.

E=mc² does not say that matter and energy are the same thing. What it does say is that a certain amount of energy is obtained when a certain amount of matter is annihilated which is a different thing entirely.

But there is a further problem in the use of the word "amount". We assume that "mass" and "energy" are quantities of "substances" - and this interpretation is too simplistic. Energy is not some kind of "magic liquid", we can't go and fill up a gallon jar with "energy". Nor could we do so with mass. Rather, mass and energy are names we give to particular manifestations or aspects of something more fundamental. Soapy Sam hit the nail on the head when he mentioned that they are aspects of the same thing.

The two faces of a coin are both "aspects" of the coin. But they are neither equal, equivalent or interchangeable. They are distinct and different, and observation of them depends on the frame of reference of the observer. Imagine a coin suspended in mid-air so that an observer on one side sees the heads and an observer on the other side sees the tails. Now, we can agree that they are both looking at a coin - the coin is the fundamental object in question. But they will disagree on an apparent aspect of the coin - if we ask each which side is facing them, one will say "heads", the other will say "tails". It would be silly to deny this and say, "Well heads is the same as tails", because it clearly isn't. Nor could we say, "The total amount of sides is two and therefore we shall blur the distinction between one side and the other". Well, we could say it, but it would be a lousy argument!

Therefore, in respect of energy/mass it would be more accurate to say that they are both superficial aspects of something fundamental. Different and distinct aspects, that depend on something unique to a particular observer. So we need to start by identifying the fundamental thing that we're looking at, and then look at what distinguishes one observer from another.

I believe the fundamental thing is momentum. If we start from the assumption that all things in the universe have a property which we call momentum, it starts to make sense. But what is "momentum"? Isaac Newton thought it was fundamental too, he defined it as, "a quantity of motion". Which, despite its simplicity is a rather good definition.

Let us start with two objects. Each has a fundamental property of momentum. We place an observer on one of the objects. From the point of view of that observer we can now define "mass" and "energy" as relative aspects of momentum.

Assuming our observer is on object A:

1. If the object B is in net motion (not conservative motion) relative to object A, then object B appears to have a quality we call "energy".

2. If the object B is stationary relative to object A, then object B appears to have a quality we call "mass".

Superficially, this appears to be a pretty weak and useless definition - but think about it. It's much more subtle than it appears.

The situation is analogous to electric and magnetic fields. If an observer is stationary with respect to an electric field, he sees only an electric field. If the observer is in motion relative to an electric field, he sees a magnetic field (and a changing electric field). In this latter case, it is actually the magnetic field that is equivalent to the momentum. The question of whether electric and magnetic fields are independent entities rather than just aspects of the same thing dependent on motion, is the same question (in form, if not substance) to the questions of mass/momentum/energy.

 

[MRC_Hans]

Im not saying it is flawed...Im saying how I am looking at(based on reading of physics) it seems flawed to me.

Trust me, it is not.

If Energy(as defined by every physics book i've read) Is just the ability to do work(move matter).

and The laws of thermodynamics are true.

No, because why couldn't it be destroyed (or used up), then?

Then E=mc2 can't mean that energy can be CONVERTED into matter and vise versa...

What does "converted" really Mean? Because It can't mean the energy destroyed and matter created because that violates thermodynamic laws.

Converted, like in exchanged. You exchange $ or € or vice versa. Nothing lost, nothing gained (yeah, forgetting exchange fees; metaphors only go so far). So the amount of energy in the universe is not constant and the amount of matter in the universe is not constant, but the amount of ehergy/matter IS constant.

I know that it takes tons of energy to split an atom and create energy out of it....But Still,Matter is being destroyed which violates thermodynamic laws.

No, it is being exchaged to energy.

It also takes tons of energy to collide particles to create matter but still you are substituing energy(destroyed) for matter(created).

Exchanging

Hans

 

[Dustin Kesselberg]

I don't believe the equation E=mc² violates any law of thermodynamics.

But there is an issue here that needs to be addressed and which I think is being widely misinterpreted.

E=mc² does not say that matter and energy are the same thing. What it does say is that a certain amount of energy is obtained when a certain amount of matter is annihilated which is a different thing entirely.

But there is a further problem in the use of the word "amount". We assume that "mass" and "energy" are quantities of "substances" - and this interpretation is too simplistic. Energy is not some kind of "magic liquid", we can't go and fill up a gallon jar with "energy". Nor could we do so with mass. Rather, mass and energy are names we give to particular manifestations or aspects of something more fundamental. Soapy Sam hit the nail on the head when he mentioned that they are aspects of the same thing.

The two faces of a coin are both "aspects" of the coin. But they are neither equal, equivalent or interchangeable. They are distinct and different, and observation of them depends on the frame of reference of the observer. Imagine a coin suspended in mid-air so that an observer on one side sees the heads and an observer on the other side sees the tails. Now, we can agree that they are both looking at a coin - the coin is the fundamental object in question. But they will disagree on an apparent aspect of the coin - if we ask each which side is facing them, one will say "heads", the other will say "tails". It would be silly to deny this and say, "Well heads is the same as tails", because it clearly isn't. Nor could we say, "The total amount of sides is two and therefore we shall blur the distinction between one side and the other". Well, we could say it, but it would be a lousy argument!

Therefore, in respect of energy/mass it would be more accurate to say that they are both superficial aspects of something fundamental. Different and distinct aspects, that depend on something unique to a particular observer. So we need to start by identifying the fundamental thing that we're looking at, and then look at what distinguishes one observer from another.

I believe the fundamental thing is momentum. If we start from the assumption that all things in the universe have a property which we call momentum, it starts to make sense. But what is "momentum"? Isaac Newton thought it was fundamental too, he defined it as, "a quantity of motion". Which, despite its simplicity is a rather good definition.

Let us start with two objects. Each has a fundamental property of momentum. We place an observer on one of the objects. From the point of view of that observer we can now define "mass" and "energy" as relative aspects of momentum.

Assuming our observer is on object A:

1. If the object B is in net motion (not conservative motion) relative to object A, then object B appears to have a quality we call "energy".

2. If the object B is stationary relative to object A, then object B appears to have a quality we call "mass".

Superficially, this appears to be a pretty weak and useless definition - but think about it. It's much more subtle than it appears.

The situation is analogous to electric and magnetic fields. If an observer is stationary with respect to an electric field, he sees only an electric field. If the observer is in motion relative to an electric field, he sees a magnetic field (and a changing electric field). In this latter case, it is actually the magnetic field that is equivalent to the momentum. The question of whether electric and magnetic fields are independent entities rather than just aspects of the same thing dependent on motion, is the same question (in form, if not substance) to the questions of mass/momentum/energy.

Basically what you are saying is that an object in motion has momentum while an object at rest has potential?


Also..How can an object not have mass and show energy at the same time?

Also..Define "energy". Im not sure I understand your defenition of it,Or if you even defined it.

Also explain how matter is created and how energy is created.

 

[Dustin Kesselberg]

Trust me, it is not.

Not saying it is.


No, because why couldn't it be destroyed (or used up), then?

That violates the laws of conservation of energy and matter.

Converted, like in exchanged. You exchange $ or € or vice versa. Nothing lost, nothing gained (yeah, forgetting exchange fees; metaphors only go so far). So the amount of energy in the universe is not constant and the amount of matter in the universe is not constant, but the amount of ehergy/matter IS constant.

No....Exchanging dollars for euros you loose dollars and gain euros,Exchanging euros for dollars you loose dollars and gain euros...But the laws of conservation of matter and energy state the amount of energy and matter in the universe remain constant.

Question:Can energy Exist without Matter?

Define-Energy...

 

[CurtC]

Dustin wrote:
So electricty is not 100% energy since it contains particles which of course is matter. Which likely weighs something.

Electrical energy is in the form of photons, which have no (rest) mass.

If Energy(as defined by every physics book i've read) Is just the ability to do work(move matter).

Someone else already asked about this, but you keep making the same assertion. Where did you read that the ability to do work is the same thing as "moving matter"? It's not really right.

How is an Atomic Bomb a small scale?

You should have asked "how is the Sun small scale?" But for most purposes down here on Earth, matter and energy remain as matter and energy respectively, so we can, in most situations, ignore the conversion. For those purposes, it's small scale.

I accused someone on another thread a few days ago of being intentionally obtuse. I should have saved that phrase for this thread. It's been explained to you again and again, but you keep posting the same basic question. I'll try to summarize:

* The laws of thermodynamics were originally written before it was known that e and m were interchangeable, and they did indeed say that energy is conserved.

* Discoveries in the 20th century taught us that they are interchangeable, so the laws of thermodynamics got modified, so that (e+m) is conserved. This is likely left out of many textbooks, because the problems students work on when dealing with thermo classes can pretty much ignore the conversion.

Because It can't mean the energy destroyed and matter created because that violates thermodynamic laws.

No, it doesn't violate thermodynamic laws. It violates the laws as they were first written, but now we know that the quantity (e+m) is conserved, so they can change from one form to another.

Do you feel that scientists don't really understand this? That's the impression I get from you.

 

[Dustin Kesselberg]

Do you feel that scientists don't really understand this? That's the impression I get from you.

I get mixed answers from various people and mixed answers from various websites,But
You explained it better than the others did...


But You say that work is not the ability to move matter? What then is "Work" and How would you Define "Energy"?