What is the substance that matter and energy are states of?

[Exapno_Mapcase]

@Ring

For Exapno’s edification it might be beneficial for him to wonder how, if mass and energy are the same thing, a system can have energy but no mass.

I see. The person made of matter living in a universe of mass that emerged from vacuum energy is telling me that I shouldn’t use the popular definitions of mathematical concepts that are being explained to me in conversational English. I’ll go off and ponder the information component of that for a while.

[Ring]

@Exapno_Mapcase

I see. The person made of matter living in a universe of mass that emerged from vacuum energy is telling me that I shouldn’t use the popular definitions of mathematical concepts that are being explained to me in conversational English. I’ll go off and ponder the information component of that for a while.

Pardon me? Vacuum energy? Surely you haven’t forgotten that I “Emerged” from the Adam and Eve non zero momentum frame as they transitioned from an excited energy state and had a cigarette.

That was no apple she was chewing on.

[Exapno_Mapcase]

If Eve was chewing on it and you emerged that would explain a lot about you. :eek:

[glowacks]

This has me very very confused, but also perhaps quite enlightened.

So mass is a property of the arrangement of the energy of a system. So if an object is moving faster, it will have more kinetic energy, and thus more mass? Is this related to relativistic mass? I thought that was just a kludge to get f=ma to work at relativistic speeds, when it’s actually relativistic momentum that increases at such speeds.

If I had a sensitive enough scale, could I measure the mass of X atoms of Element Y arranged in a crystal lattice at temperature ZK to be different from X atoms of Element Y in the same physical arrangement at temperate (Z+delta)K? And the difference in mass would be calculated partly via E=mc^2? What sort of delta are we looking at to get a measurable increase in perceived mass? (Is some of this irrelevant because it would be impossible to keep the crystal structure in shape at the temperatures needed and thus some energy would change forms to intramolecular interactions?)

[Absolute]

@glowacks

This has me very very confused, but also perhaps quite enlightened.

So mass is a property of the arrangement of the energy of a system. So if an object is moving faster, it will have more kinetic energy, and thus more mass? Is this related to relativistic mass? I thought that was just a kludge to get f=ma to work at relativistic speeds, when it’s actually relativistic momentum that increases at such speeds.

If I had a sensitive enough scale, could I measure the mass of X atoms of Element Y arranged in a crystal lattice at temperature ZK to be different from X atoms of Element Y in the same physical arrangement at temperate (Z+delta)K? And the difference in mass would be calculated partly via E=mc^2? What sort of delta are we looking at to get a measurable increase in perceived mass? (Is some of this irrelevant because it would be impossible to keep the crystal structure in shape at the temperatures needed and thus some energy would change forms to intramolecular interactions?)

The arrangement of energy does not matter, just the amount.

All else being equal, hot objects are more massive. The energy required to heat an object enough to produce a given mass increase is given by E=mc^2. Theoretically, you experiment would work.

[ricksummon]

Are we saying that kinetic energy has mass now? Then, as the classic argument goes, why don’t objects accelerated to relativistic velocities collapse into black holes? Because kinetic energy is relative, and mass is a scalar invariant, correct?

[Stranger_On_A_Train]

@Nametag

They are both manifestations of the graviniferous aether.

I prefer to think of it as oscitant quintessence but then, I just like playing with words.

It is best to consider systems as having properties of both “energy” and “mass”. These properties are related but not identical; energy refers to the system’s ultimate capacity to do mechanical work, while mass is the resistance of system to a change of state. As Ring notes, the total mass of a system cannot change, nor can its distribution as a gestalt except by transferring momentum to an external inertial body. In other words, a closed system without external influence will have the same mass properties regardless of what particle conversion or thermodynamic interactions occur within the boundaries. So you’ve combined a hadron with its antiparticle to create one or more photons; the kid weighing the shoebox in which this occurs in can’t tell any difference in terms of mass, any more than the van carrying a flock of parrots weighs less just because half the parrots are flying.

Stranger

[astro]

Orgone

[Ring]

@ricksummon

Are we saying that kinetic energy has mass now? Then, as the classic argument goes, why don’t objects accelerated to relativistic velocities collapse into black holes? Because kinetic energy is relative, and mass is a scalar invariant, correct?

Mass equals the energy of a system that cannot be transformed away.

So, think of it this way. Let’s say an object has kinetic energy because it’s moving at 10m/s. Now let’s say you start moving at 10m/s in the same direction. From your point of view what is the objects kinetic energy now?

You’ve just transformed the energy of the object away simply by changing reference frames.

Now consider two objects that are moving in different directions. These objects have a center of momentum frame, and therefore, considered as a system, they do have additional mass because their energy can’t be transformed away.

Relativistic mass can always be transformed away. Don’t use this concept.

[Jenaroph]

@The_Hamster_King

Strings – or nothing!

This may be one of the most awesome displays of cross-disciplinary nerdiness ever.

[Chronos]

Quoth falcotron:

Recently, some people have claimed that the holographic principle is a testable theory, in that it would cause the gravitational background noise caused by random fluctuations in position to show up differently, at a scale that we can just barely test today. I don’t know what the current status of that idea is.

I don’t think it’s published yet, but I’ve heard through the grapevine that the folks at the GEO experiment have managed to beat down their noise below the purported holographic limit. If true (and I reiterate that this is only the grapevine and might be in error), that would appear to rule out the holographic model (at least, until the theorists finish adding some epicycles and equants to it). A shame; it would have been such an elegant theory.

Quoth Absolute:

The arrangement of energy does not matter, just the amount.

The arrangement of the energy does matter. Mass is, ultimately, one measure of how the energy of a system is arranged.

[Engywook]

@Absolute

It is not a nitpicky technical definition, it’s a correction of a common misperception (that I shared too, until I dug out my freshman physics notes).

Mass and energy cannot be converted into each other. Rather, E=mc^2 implies that all mass has a certain amount of energy, and all energy has a certain amount of mass. They are essentially two ways of measuring the same thing.

Theoretically, if you could measure just the mass of a system, you would know how much energy it has - and vice-versa (I don’t know of any way to measure the energy content directly, though). They are not independent quantities, they are two different measurements of the same parameter, always linked by E=mc^2.

When a particle accelerator creates more particles by colliding two other particles at high speed, the kinetic energy of the two particles itself has mass, exactly equivalent to the mass of the new particles that are created.

Some of the rest mass in an atomic nucleus comes from the binding energy that keeps neutrons bound to protons. In fusion and fission reactions, some of this binding energy is given off as kinetic energy of the reaction products. If one were to look at the rest mass of the reaction products, you would find that a small amount of mass has gone. But it hasn’t been “converted” into energy - it was already energy, the binding energy of the fusing nuclei. The kinetic energy of the reaction products had the “missing” mass.

If one could construct a truly closed system, no matter how many fusion or fission reactions occurred, you would find that it always had the same mass. Before any reactions occurred, most of that mass would be in binding energy in the nuclei. After many reactions have occurred, some of that mass would in thermal energy of the nuclei.

Of course, if you could not keep the system truly closed, some energy would escape, and you would find that the mass of the system had in fact decreased. But the mass was not “converted” into energy. The energy that escaped had mass itself.

Mass and energy cannot be “converted” into each other. They are the same thing.

Thank you for this post. I stand clearly corrected on a misconception I have long cherished… and worse, am guilty of repeating to others. My salute to a true soldier in the fight against ignorance!

[falcotron]

@Chronos

I don’t think it’s published yet, but I’ve heard through the grapevine that the folks at the GEO experiment have managed to beat down their noise below the purported holographic limit. If true (and I reiterate that this is only the grapevine and might be in error), that would appear to rule out the holographic model (at least, until the theorists finish adding some epicycles and equants to it). A shame; it would have been such an elegant theory.

That is a shame.

As a side note, when I first read about the GEO experiment (in some pop-science context), they said that a negative result could disprove not only the holographic model, but also a wide class of discrete-spacetime models. But I couldn’t find any more info on what they were referring to. Surely they don’t mean that LQG, strings with T-duality, and so on are out the window, do they?

[ricksummon]

If there truly is no physical difference between mass and energy, then:

1. Why do particles “without” mass always travel at the speed of light, while particles “with” mass cannot ever be accelerated to that speed?

2. Why is the Higgs boson important at all? If mass is exactly the same thing as energy, then why should anyone care if this particle interacts with electrons and not photons?

3. Why are people in this thread actually claiming that kinetic energy (which is relative) has mass (which is a scalar invariant)? I know full well that “relativistic mass” is an inaccurate description.

4. Isn’t mass specifically associated with inertia? That is, you can accelerate a massive particle from rest by applying force, but a massless particle cannot be accelerated or decelerated, or in any way travel at a velocity other than c.

[Stranger_On_A_Train]

If what you’re taken away from the discussion is that there is no difference between mass and energy, you’ve missed a couple of salient points. Mass and energy are both properties of a system; they are related, but both are independently conserved. You can convert bound energy in a system from one “type” to another, but the mass of the system (which is a property at the system level) will remain the same regardless of that conversion.

As to the speed at which massy and massless particles move, the fact is that they all move at c; it is just that massy particles have a component of movement along the time axis, whereas a massless particle exists simultaneously at all points along its interval from genesis to destruction.

The property of inertia, like gravity, is not really fully understood. We have a mathematical model that describes how particles with mass display an inertial resistance to changes of kinetic energy state, but not an underlying mechanic for what causes inertia. From a very simplistic viewpoint, inertia appears to be tied to some kind of invariant background, like a modern version of aether, which the Higgs field (sort of) is, although in a fashion far more complex than simple scalar field.

[Nancarrow]

The word the OP is looking for is wakalixes.

[Spatial_Rift_47]

@Absolute

Mass and energy are not states of anything, they are properties.

Now - what they are properties of?

Curvature. If you think about it from a GR perspective, what is the one and only thing that all types of mass and energy always have in common? They change the curvature tensor. Depending on what kind of curvature you have, it will either have rest mass (and consequently inertia) or no rest mass.

@Absolute

What “is” kinetic energy?

Still working on this one.