We are having a semantic argument over the meaning of "pure".

Considering energy and mass are interchangeable (and exist simultaneously), there are many possible states between pure mass at zero energy and pure energy at zero mass.

Photons are massless. Thus, pure energy.

I don't deny the mass equivalence of energy. Or the "existence" of relativistic mass. Or that a photon has momentum.

But if you accept photons propagate at c, they must be massless -- and therefore, pure energy.

Photons in fact do have mass -- otherwise they would have zero momentum, which we know is not the case (when we bounce them into stuff they exert a pressure). In the old days, scientists used to differentiate between "rest mass" and "relativistic mass", and so they would say that a photon has zero rest mass but nonzero relativistic mass. Eventually they decided that this was not only confusing, but also unnecessary since special relativity showed us that mass and energy are equivalent.

Nowadays, whether a scientist calculates using mass or energy depends only on the type of work. The HEP physicists almost invariably use energy (e.g., the mass of the Higgs boson is said to be 125 GeV, which is a unit of energy), while astronomers tend to do their work in units of mass, which fits naturally with their Newtonian calculations.

The point is that mass and energy are equivalent descriptions of a particular property of a system. Neither mass nor energy are things that exist in and of themselves. It makes no more sense to speak of "pure energy" than it does to speak of "pure mass".

 

Geeze, mellow out dude.

Wasn't that easy!

 

Mass is multi-defined in our science.....depending on the field. We need a strict qualifier.

That qualifier should be inertia. Light is emitted, suspended, and dissolving, inertia.

I'm guessing that there is only 80-90% of the mass(inertia) left from first light. There is a good chronological record of this in the nite sky.

Our real time universe is in all probability a vast un-dense field of dark cinders.

Who says pessimism is not a physical property?

 

Wasn't that easy!

Hi,

Hey you're a good sport. I returned the 'like' because that's pretty cool of you.
I think i'll take a rest on this thread though because i dont study this stuff anymore as it is not as interesting to me as the more practical things these days. I find that the older i get, the more i concentrate on things that affect me more directly the better off i am.
I still have to do one more reply though

 

Photons in fact do have mass -- otherwise they would have zero momentum, which we know is not the case (when we bounce them into stuff they exert a pressure). In the old days, scientists used to differentiate between "rest mass" and "relativistic mass", and so they would say that a photon has zero rest mass but nonzero relativistic mass. Eventually they decided that this was not only confusing, but also unnecessary since special relativity showed us that mass and energy are equivalent.

Nowadays, whether a scientist calculates using mass or energy depends only on the type of work. The HEP physicists almost invariably use energy (e.g., the mass of the Higgs boson is said to be 125 GeV, which is a unit of energy), while astronomers tend to do their work in units of mass, which fits naturally with their Newtonian calculations.

The point is that mass and energy are equivalent descriptions of a particular property of a system. Neither mass nor energy are things that exist in and of themselves. It makes no more sense to speak of "pure energy" than it does to speak of "pure mass".

Hi,

It makes sense what you say, and how NSA put the energy being a property of matter, and i think those are good views.
However, in your last sentence i dont think i can agree with that because what i have read more recently suggests that matter 'condenses' out of energy, and you will note that we experience matter and deduce the energy. The wording i read is energy "congeals" into matter but the mechanism is still unknown.

What i see in ordinary observation is that we might act on matter, thus causing it to move. If we push one piece of matter into a second piece of matter, some of the thing we call energy transfers to the second mass. This could lead us to say that the matter has a property associated with it, as to how much energy it 'has' at the time. But what was it that actually transferred to the second mass. IF we look at energy as a byproduct of movement, then there is no such thing as energy it's just the mass taking on different states. But if we look at the movement as a byproduct of applied energy, then energy is a real thing of it's own.
The way i see it is we would have to know what came first at the big bang, the energy or the mass, and the way i understand it is that it started from energy and that eventually "congealed" enough to become mass.

 

Hi,

It makes sense what you say, and how NSA put the energy being a property of matter, and i think those are good views.
However, in your last sentence i dont think i can agree with that because what i have read more recently suggests that matter 'condenses' out of energy, and you will note that we experience matter and deduce the energy. The wording i read is energy "congeals" into matter but the mechanism is still unknown.

What i see in ordinary observation is that we might act on matter, thus causing it to move. If we push one piece of matter into a second piece of matter, some of the thing we call energy transfers to the second mass. This could lead us to say that the matter has a property associated with it, as to how much energy it 'has' at the time. But what was it that actually transferred to the second mass. IF we look at energy as a byproduct of movement, then there is no such thing as energy it's just the mass taking on different states. But if we look at the movement as a byproduct of applied energy, then energy is a real thing of it's own.
The way i see it is we would have to know what came first at the big bang, the energy or the mass, and the way i understand it is that it started from energy and that eventually "congealed" enough to become mass.

When you see matter 'condenses/congealed' out of energy just know it's a loose term. Condensation, like steam to water (usually a more stable state for h2o) is the same substance in different physical states due to conditions but I'm pretty the physicist actually means something physically more complex than what you read.
One more time, The energy is a property of the system (physical objects in a environment ) , not of the system's parts. Photons do not exist in fixed numbers. Photons can be created and destroyed at our will like water to steam. Does this mean we can create 'pure energy' from matter? Of course not. The properties of energy, momentum, and angular momentum they have were there beforehand, but not in the form of photons.

 

Hi,

It makes sense what you say, and how NSA put the energy being a property of matter, and i think those are good views.
However, in your last sentence i dont think i can agree with that because what i have read more recently suggests that matter 'condenses' out of energy, and you will note that we experience matter and deduce the energy. The wording i read is energy "congeals" into matter but the mechanism is still unknown.

Matter is a fuzzy word with no real physical meaning. We can say "Matter is a collection of molecules", but then what of the atoms in the molecules -- are they not matter? If not, then energy/mass is clearly more fundamental than matter, and the concept of matter only applies to "big" things, like houses.

Perhaps we can say "Matter is a collection of atoms", but what of the nuclei in the atoms -- are protons and neutrons not matter? Ok, then we can say that "Matter is a collection of hadrons", but what of the quarks that comprise them? Fine, then "Matter is a collection of quarks", but what of electrons? We can't sit on a chair without electrons!

So, either matter is everything, or matter is nothing. Therefore, "matter" doesn't matter.

The way i see it is we would have to know what came first at the big bang, the energy or the mass, and the way i understand it is that it started from energy and that eventually "congealed" enough to become mass.

Mass and energy are equivalent. They are two words that describe the same property. Whether we are talking about a quantum field, or a house, or the fiery ball of plasma that was the universe at time t=0, if we know its energy then we automatically know its mass, and vice versa. It doesn't make sense to wonder which came first.

 

It doesn't make sense to wonder which came first.

Wait. According to @nsaspook, wasn't that the rooster?

 

The properties of energy, momentum, and angular momentum they have were there beforehand, but not in the form of photons.

That's where I get a little lost ... according to the standard model, for every particle there's an antiparticle. And when they meet, the annihilate ... and turn into energy. That is, photons ... isn't that right? What am I missing?

 

That's where I get a little lost ... according to the standard model, for every particle there's an antiparticle. And when they meet, the annihilate ... and turn into energy. That is, photons ... isn't that right? What am I missing?

Conserved quantities remain conserved after particle collisions. When an electron and a positron collide, they annihilate each other, producing two photons in the process. They didn't "turn into energy" -- the energy in the resulting photons (their wavelengths) is equal to the energy of the originating electron and positron.

 

Conserved quantities remain conserved after particle collisions. When an electron and a positron collide, they annihilate each other, producing two photons in the process. They didn't "turn into energy" -- the energy in the resulting photons (their wavelengths) is equal to the energy of the originating electron and positron.

Yes, but photons have zero mass... Matter-antimatter annihilation is the perfect corroboration of e=mc^2

 

Yes, but photons have zero mass... Matter-antimatter annihilation is the perfect corroboration of e=mc^2

Photons do have mass, otherwise they would have no momentum. The correct equivalence is E = sqrt[(mc^2)^2 + (pc)^2], where m is the so-called rest mass.

 

Photons do have mass, otherwise they would have no momentum. The correct equivalence is E = sqrt[(mc^2)^2 + (pc)^2], where m is the so-called rest mass.

What they have is an amount of energy with an equivalent mass ... but in reality they have no mass ... otherwise they wouldn't be able to travel at the speed of light.

The photon has zero rest mass and always moves at the speed of light within a vacuum.​

But maybe we're arguing the same thing, and are talking in circles.

Also: Experimental checks on photon mass

 

What they have is an amount of energy with an equivalent mass ... but in reality they have no mass ... otherwise they wouldn't be able to travel at the speed of light.

The photon has zero rest mass and always moves at the speed of light within a vacuum.​

But maybe we're arguing the same thing, and are talking in circles.

Also: Experimental checks on photon mass

I dropped out of the conversation. The equivalence snobs are annoying me.

 

When you see matter 'condenses/congealed' out of energy just know it's a loose term. Condensation, like steam to water (usually a more stable state for h2o) is the same substance in different physical states due to conditions but I'm pretty the physicist actually means something physically more complex than what you read.
One more time, The energy is a property of the system (physical objects in a environment ) , not of the system's parts. Photons do not exist in fixed numbers. Photons can be created and destroyed at our will like water to steam. Does this mean we can create 'pure energy' from matter? Of course not. The properties of energy, momentum, and angular momentum they have were there beforehand, but not in the form of photons.

Hi again,

Real quick, i dont think we will be able to come to a complete agreement on any of this mostly because there is still much being done in this area some of which we dont even know about just yet. I do realize that the process would be more complex than the analogy, but the analogy is there to show us something even if not everything.

You might take a minute to show how you see the process of how energy transfers from one mass to the other such as in two pool table balls that come into 'contact', be they rigid or semi rigid bodies, your choice. I'll start...
When the two balls come close enough the electromagnetic fields of each of the electrons in the atoms start to interact strongly. The moving ball fields are repelled from the non moving ball fields, and eventually the force is enough to overcome the sticking friction of the non moving ball and it starts to move.
Your job, should you decide to accept it, is to show how the energy gets from one ball to the other. Your job is not to show that it DOES transfer, we know that already, nor to show the amount of energy that gets transferred, but to show the exact mechanism by which the energy transfers, period.

 

I dropped out of the conversation. The equivalence snobs are annoying me.

Hi,

I was reading your posts, i hope i did not miss one. If so, i'd be happy to read it.

 

Matter is a fuzzy word with no real physical meaning. We can say "Matter is a collection of molecules", but then what of the atoms in the molecules -- are they not matter? If not, then energy/mass is clearly more fundamental than matter, and the concept of matter only applies to "big" things, like houses.

Perhaps we can say "Matter is a collection of atoms", but what of the nuclei in the atoms -- are protons and neutrons not matter? Ok, then we can say that "Matter is a collection of hadrons", but what of the quarks that comprise them? Fine, then "Matter is a collection of quarks", but what of electrons? We can't sit on a chair without electrons!

So, either matter is everything, or matter is nothing. Therefore, "matter" doesn't matter.


Mass and energy are equivalent. They are two words that describe the same property. Whether we are talking about a quantum field, or a house, or the fiery ball of plasma that was the universe at time t=0, if we know its energy then we automatically know its mass, and vice versa. It doesn't make sense to wonder which came first.

Hello,

So if you have steam and that condenses into water, it does not make sense to ask which came first?

If you believe that, then you should be telling the people who said this not me. I'm just quoting what i read here and there.

 

I dropped out of the conversation. The equivalence snobs are annoying me.

It's called real science, not snobbery. Please don't confuse pop-science with what is used in the field or in abstract to explain solid-state matter structure changes using electron volts, etc ... .

 

Hi again,

Real quick, i dont think we will be able to come to a complete agreement on any of this mostly because there is still much being done in this area some of which we dont even know about just yet. I do realize that the process would be more complex than the analogy, but the analogy is there to show us something even if not everything.

You might take a minute to show how you see the process of how energy transfers from one mass to the other such as in two pool table balls that come into 'contact', be they rigid or semi rigid bodies, your choice. I'll start...
When the two balls come close enough the electromagnetic fields of each of the electrons in the atoms start to interact strongly. The moving ball fields are repelled from the non moving ball fields, and eventually the force is enough to overcome the sticking friction of the non moving ball and it starts to move.
Your job, should you decide to accept it, is to show how the energy gets from one ball to the other. Your job is not to show that it DOES transfer, we know that already, nor to show the amount of energy that gets transferred, but to show the exact mechanism by which the energy transfers, period.

How about this as a quick starter.
The 'energy' we see transferred as you call it is because the two balls become a system where momentum must be conserved. The Coulombic forces (force is just the change of momentum in time) transfer momentum between the objects while they are a system while the energy of this system will now be redistributed as a system not transferred to separate parts.

http://electron6.phys.utk.edu/101/CH2/conservation_of_momentum.htm

 

I dropped out of the conversation. The equivalence snobs are annoying me.

Funny how arguing about the fundamentals can become such a big deal among geeks...

I'm not used to this sort of discussion, so I'm guessing there's a "school" out there that argues against the equivalence principle...