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m74z00219
2009-Aug-06, 06:31 AM
Normally, what we think of matter is quantified by mass. However, the mass quantity contains not just the protons, electrons, and neutrons, but the kinetic energy, inter-atomic bond energy, inter-molecular bond energy, and inter-nucleon bond energy as well.

Even the proton is made up of massive quarks and massless gluons. When the mass of proton matter is measured, it contains the energy of massive and massless particles.

It seems to me that the definition of matter is a bit hazy, isn't it?

What if we defined matter as that set of particles that are both massive and fundamental (indivisible)? Or, is this the "true" scientific definition of matter?

Also, how do we know that a particle is truly elementary and not, say, infinitely divisible?

Thanks all for your time,
m74

astromark
2009-Aug-06, 07:00 AM
No. I do not think the divisibility of mass defines it as mater or not... Without doing the 'Wicki.,' search or going to 'google'... I enjoy these questions and have decided that mater is more than atoms and sub atomic particles. I would describe mater as the collection of particles and compounds that have molecular structures that have formed into detectable mass.

astromark
2009-Aug-06, 07:06 AM
:)sorry for this but...'What's the mater? never mind.
What's the mind? It does not mater...

gzhpcu
2009-Aug-06, 07:09 AM
Anything that has mass and volume?

gzhpcu
2009-Aug-06, 07:12 AM
And mass is related to weight, which is related to interaction with gravity.

Now enter the Higgs boson, predicted by the Standard Model as the particle which imparts mass to the elementary particles... if it exists...:)

astromark
2009-Aug-06, 10:12 AM
Anything that has mass and volume?

I knew that...:( I did:)!

Then how do we describe a black hole.? It seems to be possible that all that mass in a singularity ( no volume ) I must be not understanding some vital bit... but rules are made to be broken. I still think your 'Anything with mass and volume' works best...

Jeff Root
2009-Aug-06, 01:22 PM
Mass is not an essential property of matter. Particles which are massless
are also matter.

I may not be able to define it, but I know it when I detect it. :)

-- Jeff, in Minneapolis

Jeff Root
2009-Aug-06, 01:26 PM
Mark,

Hard and gentle.

Figure that one out! Use your brain!

-- Jeff, in Minneapolis

Cougar
2009-Aug-06, 01:28 PM
Also, how do we know that a particle is truly elementary and not, say, infinitely divisible?

We don't.

Jeff Root
2009-Aug-06, 02:33 PM
Also, a particle doesn't necessarily occupy any particular volume. Electrons,
for example, are essentially pointlike.

-- Jeff, in Minneapolis

gzhpcu
2009-Aug-06, 03:40 PM
Also, a particle doesn't necessarily occupy any particular volume. Electrons,
for example, are essentially pointlike.

-- Jeff, in Minneapolis
That is only because QM models them as zero dimensional. This can only be an approximation. QM is not the final theory. String theory models them as one dimensional strings, which is assuredly another approximation.

GOURDHEAD
2009-Aug-06, 03:40 PM
At Planck dimensions even mass is difficult to define. The best definition I've seen is: 'resistance to motion" in momentum equations. We just don't seem to know where we came from, where we're going, what we're made of, how we came to be, why we're here, how long we can stay, nor where here is. Otherwise, we're pretty much doubt free.

Pmb61
2009-Aug-06, 10:18 PM
There is no agreed upon definition of the term matter. Some say that history has shown that all attempts at definition have failed. Some us the term to refer to an electric or magnetic field has being matter. Since light has inertial mass (not to be confused with proper mass) then it too can be said to be a form of matter.

Jeff Root
2009-Aug-07, 04:48 AM
I think most people would agree that all physical particles are matter.
We might have a problem with virtual particles.
And gravitons...
And dark matter... even though it has "matter" right in its name!

-- Jeff, in Minneapolis

WayneFrancis
2009-Aug-07, 05:21 AM
I knew that...:( I did:)!

Then how do we describe a black hole.? It seems to be possible that all that mass in a singularity ( no volume ) I must be not understanding some vital bit... but rules are made to be broken. I still think your 'Anything with mass and volume' works best...

While the singularity might not have any volume itself that is inside of the EH and thus outside of our universe so you can consider the EH of the BH as its volume. That is how I would look at it.

Jeff Root
2009-Aug-07, 05:46 AM
While the singularity might not have any volume itself that is inside
of the EH and thus outside of our universe so you can consider the
EH of the BH as its volume. That is how I would look at it.
Doesn't work for me. I know that interior to the event horizon is
almost entirely empty. I'm not going to think of it as matter. Also,
the event horizon is an arbitrary dividing surface. At least as good
a case could be made for the photon sphere as the dividing surface,
in my opinion. But I really think the matter is (almost) all at the
center of a black hole, even if that is beyond everyone's ability to
observe, and it doesn't have any particular volume.

-- Jeff, in Minneapolis

Bruceleeeowe
2009-Aug-07, 11:54 AM
No. I do not think the divisibility of mass defines it as mater or not... Without doing the 'Wicki.,' search or going to 'google'... I enjoy these questions and have decided that mater is more than atoms and sub atomic particles. I would describe mater as the collection of particles and compounds that have molecular structures that have formed into detectable mass.

I'm agree with you but additionaly I think it also consists of some of energy.

m74z00219
2009-Aug-07, 06:02 PM
Wow, what a great conversation.

@astromark, Jeff Root

I guess I'm just searching for rigid distinction between matter and energy. I wanted to call massless particles a form of "energy" and massive particles "matter", but now I'm not so sure.

@Pmb61

I could be very happy calling every particle matter.



I guess the point is that matter and energy are the same thing, but in different forms.
Wait, I think I got it!
Matter, intrinsically, does nothing except be. While energy is that which causes change. What does everyone think of this definition?

For example, a photon streaking through the universe bends spacetime (change) and when it hits a copper plate, an electron is kicked up (more change).


Hmm, I'm still not sure how comfortable I am with that. Anyone?

Durakken
2009-Aug-07, 06:40 PM
Wow, what a great conversation.

@astromark, Jeff Root

I guess I'm just searching for rigid distinction between matter and energy. I wanted to call massless particles a form of "energy" and massive particles "matter", but now I'm not so sure.


Matter and Energy is the exact same thing...How that works out beyond e=mc^2, no clue...

Durakken says, "Matter is all that matters!"

korjik
2009-Aug-07, 07:12 PM
That is only because QM models them as zero dimensional. This can only be an approximation. QM is not the final theory. String theory models them as one dimensional strings, which is assuredly another approximation.

incorrect. Electrons are still considered point sources because its diameter is smaller than we can measure. That is really really tiny.

Boratssister
2009-Aug-07, 07:45 PM
Hi , I'm new and very amateur . Forgive me if I appear stupid.
I would think that matter is anything that exists, Is '' nothing '' possible? or is that on another thread? . I mean is there ''nothing'' in an absolute vacuum ?is the fabric of space time matter?so I would say, anything that we experience/observe or have the potential to experience/observe is matter.

Jeff Root
2009-Aug-07, 11:16 PM
Just off the top of my head, here are a few examples of things that exist
but are not matter:

Happiness, getting out of bed, the number 4, north, distance, time, speed,
being next in line, King Lear, a sharp pain in your left side, failing to catch
a fish today.

-- Jeff, in Minneapolis

Jeff Root
2009-Aug-07, 11:29 PM
I guess I'm just searching for rigid distinction between matter and
energy. I wanted to call massless particles a form of "energy" and
massive particles "matter", but now I'm not so sure.
Mass is a form of energy. It is, in fact, the densest form of energy.
A quantity of mass represents more energy than can be contained
in any other form of energy on a similar size scale.



Wait, I think I got it!
Matter, intrinsically, does nothing except be. While energy is that
which causes change. What does everyone think of this definition?
It isn't a definition, but it is a useful description which helpfully
characterizes the relationship between matter and energy.

-- Jeff, in Minneapolis

Tobin Dax
2009-Aug-08, 12:11 AM
Wait, I think I got it!
Matter, intrinsically, does nothing except be. While energy is that which causes change. What does everyone think of this definition?

For example, a photon streaking through the universe bends spacetime (change) and when it hits a copper plate, an electron is kicked up (more change).


Hmm, I'm still not sure how comfortable I am with that. Anyone?
Does a photon bend spacetime? I was under the impression that it didn't.

But I disagree with the idea of energy being change. Interactions cause change. Energy is a quantity, not an interaction. Force, impulse, and torque are all interactions, but mass, energy, and momentum are not interactions. "Quantity" is a clumsy way to describe the latter three, but I don't really have anything better.

grav
2009-Aug-08, 02:20 AM
Wait, I think I got it!
Matter, intrinsically, does nothing except be. While energy is that which causes change. What does everyone think of this definition?That is precisely how I think about it also. Matter is simply that which exists and energy is a property of matter, among many others, that is used to help describe what it is or what it does when interacting with other forms of matter.

grav
2009-Aug-08, 02:21 AM
We just don't seem to know where we came from, where we're going, what we're made of, how we came to be, why we're here, how long we can stay, nor where here is. Otherwise, we're pretty much doubt free.:)

gzhpcu
2009-Aug-08, 11:37 AM
incorrect. Electrons are still considered point sources because its diameter is smaller than we can measure. That is really really tiny.
That is not what I said, I said they are certainly not zero dimensional. You call them really, really tiny, I said it is an approximation.

With our accelerators we can explore down to around 10-17meters, whereas the Planck length is 10-35meters. So a point is a good approximation, but only that.

Boratssister
2009-Aug-08, 01:15 PM
Just off the top of my head, here are a few examples of things that exist
but are not matter:

Happiness, getting out of bed, the number 4, north, distance, time, speed,
being next in line, King Lear, a sharp pain in your left side, failing to catch
a fish today.

-- Jeff, in Minneapolis

All the above can only be achieved because of matter I think. However is there matter in an absolute vacuum ?

gzhpcu
2009-Aug-08, 01:49 PM
All the above can only be achieved because of matter I think. However is there matter in an absolute vacuum ?
Yes, virtual particles (quantum foam).

Boratssister
2009-Aug-08, 04:20 PM
Yes, virtual particles (quantum foam).

So does that mean that ,nothing, as in a completely empty space can not exist? Is quantum foam matter?

gzhpcu
2009-Aug-08, 05:11 PM
So does that mean that ,nothing, as in a completely empty space can not exist? Is quantum foam matter?
That is my understanding....

Tucson_Tim
2009-Aug-08, 05:27 PM
What is matter?

"Matter is frozen energy," Einstein said, relating the essence of his insight into the mass-energy relationship.

NorthernBoy
2009-Aug-08, 05:38 PM
Normally, what we think of matter is quantified by mass.

This, I think, is an error from which many others flow when people approach physics, because many of us don't agree with the statement.

What we view as matter is a collection of particles with various characteristics pertaining to both "inherent" qualities, and to how they interact with other particles. We give these characteristics names and values, and they include charge, spin, lepton number, and mass (amongst others). If you can accept that something is real with a charge of zero, then why not also accept that something is real with a mass of zero?

I know that in the everyday world mass is a very important quantity, but in physics we really just view it as yet one more number to associate with things, not really any more "real" than any of the others, and so we should not mix "having mass" with "being matter" in any strict sense.

Durakken
2009-Aug-08, 07:39 PM
I would say that matter is a state of energy that happens when the type of energy (particle) is capable of generating mass(i.e. gravity)

In other words all "particles" are "energy." Matter is the state when a particle's energy level is sufficient to have mass.

I don't think this is all together wrong, but I also know it's not exactly right...

If this interpretation is correct it would mean that each particle can produce gravity, but do so at different energy levels. The particles that make up atoms as we know them just have a low energy level needed while photons need a high level or high concentration or something like that...

The idea is liken to the concept of matter with differing states, frozen, solid, gas, etc... just applied to particles.

Seems pretty reasonable to me...

m74z00219
2009-Aug-08, 07:50 PM
I think I feel more comfortable calling all particles of the standard model energy rather matter. My reasoning being the same. All of these particles affect the shape of the fabric of spacetime.

By the same token, that's what makes them real. I now realize that previous statement will get me into trouble when considering the virtual particles of the quantum foam.

However, I'm still happy recognizing matter as "frozen energy" as someone put it.

NorthernBoy
2009-Aug-08, 08:19 PM
I would say that matter is a state of energy that happens when the type of energy (particle) is capable of generating mass(i.e. gravity).

Well, you may say that, but it's not really leading anywhere. You are trying to impose your narrative on the physical world, which might help you to organise things in your mind, but is mush more likely to simply lead you down a dead end.

Durakken
2009-Aug-08, 08:28 PM
Well, you may say that, but it's not really leading anywhere. You are trying to impose your narrative on the physical world, which might help you to organise things in your mind, but is mush more likely to simply lead you down a dead end.

That's a bit presumptuous considering we don't know where mass comes from currently.

Even if we find the higgs, as far as I have heard, you still need to figure out why some particles interact with the field to create mass and why others don't.

cosmocrazy
2009-Aug-08, 08:48 PM
If we consider matter to be nothing more than condensed energy then this answers your question, "matter" is the definition of condensed energy which when reaching a certain dense quantity becomes physically measurable to have volume i.e at the Planck length. This is the way i like to define it anyway, a system therefore contains matter & energy of which can be measured by its mass.

astromark
2009-Aug-08, 09:35 PM
Stop and take stock of what you are suggesting here... that energy is mass. We know that's not right. Matter at some point in the past may well have been energy, but to say matter is energy or energy is mater... no that's a distortion of what we know. What is it that we actually know... that we do not yet know everything. This sort of incomplete assumption built on propersitions unfounded are not helpful. Which I must add is no reason for us not to search, learn and question... so in conclusion,. Keep looking for all that is written by the knowledgeable. This internet thing... a wonderful tool... I suggest you step back, take a breath and look at what is being said or implied. Excepting that all I think I know may not be all there is to know. But I am excepting of my incompetent view and trying to fix it. Mark.

cosmocrazy
2009-Aug-08, 09:46 PM
but are you not contradicting yourself a little Mark?

If we consider "matter" to have formed from the primordial soup of energy and then consider the conservation law also, then we could also consider that "matter" is nothing more than energy in a different form, i.e concentrated, or as refereed to earlier "frozen energy". Surely when the total mass of a system is measured then that includes everything contained in that system which quantifies the mass, don't even rest massless particles add mass to the system from their motion energy?

GOURDHEAD
2009-Aug-09, 02:54 AM
It may be helpful to think of matter as one of the many configurations of mass than can form/exist in the more or less macroscopic scales of existence. It is always mass, rather than matter, that is expressed in the equations of physics. Due to pair anihilation/formation, it is convenient to see mass as a form of potetial energy. The geometric properties of the Higgs field, whether or not they are separable from the absolute physical vacuum may shed more light on the nature of mass as we develop more mature paradigms.

astromark
2009-Aug-09, 03:08 AM
Thank you 'Gourdhead' you have said better than I was trying to..
" It is always mass, rather than mater."
Am I condradicting myself ? Yes, and I should be punished for this...:(I will change tack while the paint is drying... Present me with new information and I'm yours...:)Mark.

gzhpcu
2009-Aug-09, 07:34 AM
It may be helpful to think of matter as one of the many configurations of mass than can form/exist in the more or less macroscopic scales of existence. It is always mass, rather than matter, that is expressed in the equations of physics. Due to pair anihilation/formation, it is convenient to see mass as a form of potetial energy. The geometric properties of the Higgs field, whether or not they are separable from the absolute physical vacuum may shed more light on the nature of mass as we develop more mature paradigms.
Perhaps, but then the question becomes "what is mass"?

And is the massless photon considered matter?

:confused:

astromark
2009-Aug-09, 08:03 AM
Perhaps, but then the question becomes "what is mass"?

And is the massless photon considered matter?

:confused:

Mass is matter.

and of the photon at rest ? does no longer exist. While it was moving it was both a wave form and a particle. Just let that digest... stay calm...mark:)

gzhpcu
2009-Aug-09, 08:26 AM
Mass is matter.


Ooh, yes I see: mass is matter and matter is mass... good that we got that cleared up...:)

astromark
2009-Aug-09, 10:16 AM
Not that it is now, but may once have been .

I am trying to tell you that until we have more information from the results of advanced testing of The Large Hadron Collider., and that those results have been tested challenged and confirmed I can not possibly know how to answer this question with any absolute certainty. It would appear as if we are in agreement, Yes.

gzhpcu
2009-Aug-09, 11:06 AM
If we are trying to investigate Planck-sized objects, I don't think we will ever get things cleared up, short of building a collider the length of the Milky Way...:)