Matter - Tilted Forum Project Discussion Community

MageB420666 · 10-20-2004, 08:01 PM

Ok I know this is probably a stupid question, but I am just getting tired of wondering about it so I thought I would ask.

What is matter?

I know mass is matter/volume, and I know what volume is, but what exactly is matter? I'm not talking, atoms, protons, neutron, electrons, and the really small things that make them up.

I am talking about what the absolute building material is. What is the absolutely smallest particle there is made of? Do we even know? Am I just gonna have to keep getting agravated when I try to think about it?

mo42 · 10-20-2004, 08:17 PM

We don't know for sure what the smallest possible particle is. Right now we think it's quarks, which make up protons, neutrons, etc. There's also crazy stuff like gluons that I don't really understand. Your question bothers me also, since it's one of those fundamental things about the universe that remains a mystery.

NeoRete · 10-20-2004, 08:40 PM

We were talking about this in my phyisics class last year, and there is not a "definite answer" - yet. My understanding is the intrinisic properties of matter go past 3 dimensions and our current realm of understanding.

I got this from http://www.dctech.com/physics/features/0801.php you might still be aggrivated about trying to think about it though:

Quote:

In the case of neutrons and protons we can divide them up into smaller particles called "quarks". Quarks are not "pure charge" either, they too have mass, size, and a variety of properties that require more study to understand - "up", "charm", "spin", "strangeness"... What about quarks? What are they made of? ...We can fundamentally never find something which is only charge, it will always be a thing with properties including charge that we find - even if all other property values were zero somehow.

For a relatively easy explanation of where we go from here, try M-theory, the theory formerly known as strings. Here particles such as electrons are seen as vibration modes on strings. This theory strives to describe everything observed, from electrons to black holes. For more information, search for "string theory", "theory of everything", "M-branes"... you'll get to recognize some of the basic search phrases as you go.

M-theory, the theory formerly known as Strings (from http://www.damtp.cam.ac.uk/user/gr/public/qg_ss.html )

Quote:

The Standard Model
In the standard model of particle physics, particles are considered to be points moving through space, tracing out a line called the World Line. To take into account the different interactions observed in Nature one has to provide particles with more degrees of freedom than only their position and velocity, such as mass, electric charge, color (which is the "charge" associated with the strong interaction) or spin.

The standard model was designed within a framework known as Quantum Field Theory (QFT), which gives us the tools to build theories consistent both with quantum mechanics and the special theory of relativity. With these tools, theories were built which describe with great success three of the four known interactions in Nature: Electromagnetism, and the Strong and Weak nuclear forces. Furthermore, a very successful unification between Electromagnetism and the Weak force was achieved (Electroweak Theory), and promising ideas put forward to try to include the Strong force. But unfortunately the fourth interaction, gravity, beautifully described by Einstein's General Relativity (GR), does not seem to fit into this scheme. Whenever one tries to apply the rules of QFT to GR one gets results which make no sense. For instance, the force between two gravitons (the particles that mediate gravitational interactions), becomes infinite and we do not know how to get rid of these infinities to get physically sensible results.

String Theory
In String Theory, the myriad of particle types is replaced by a single fundamental building block, a `string'. These strings can be closed, like loops, or open, like a hair. As the string moves through time it traces out a tube or a sheet, according to whether it is closed or open. Furthermore, the string is free to vibrate, and different vibrational modes of the string represent the different particle types, since different modes are seen as different masses or spins.

One mode of vibration, or `note', makes the string appear as an electron, another as a photon. There is even a mode describing the graviton, the particle carrying the force of gravity, which is an important reason why String Theory has received so much attention. The point is that we can make sense of the interaction of two gravitons in String theory in a way we could not in QFT. There are no infinities! And gravity is not something we put in by hand. It has to be there in a theory of strings. So, the first great achievement of String Theory was to give a consistent theory of quantum gravity, which resembles GR at macroscopic distances. Moreover String Theory also possesses the necessary degrees of freedom to describe the other interactions! At this point a great hope was created that String Theory would be able to unify all the known forces and particles together into a single `Theory of Everything'.

From Strings to Superstrings
The particles known in nature are classified according to their spin into bosons (integer spin) or fermions (odd half integer spin). The former are the ones that carry forces, for example, the photon, which carries electromagnetic force, the gluon, which carries the strong nuclear force, and the graviton, which carries gravitational force. The latter make up the matter we are made of, like the electron or the quark. The original String Theory only described particles that were bosons, hence Bosonic String Theory. It did not describe Fermions. So quarks and electrons, for instance, were not included in Bosonic String Theory.

By introducing Supersymmetry to Bosonic String Theory, we can obtain a new theory that describes both the forces and the matter which make up the Universe. This is the theory of superstrings. There are three different superstring theories which make sense, i.e. display no mathematical inconsistencies. In two of them the fundamental object is a closed string, while in the third, open strings are the building blocks. Furthermore, mixing the best features of the bosonic string and the superstring, we can create two other consistent theories of strings, Heterotic String Theories.

However, this abundance of theories of strings was a puzzle: If we are searching for the theory of everything, to have five of them is an embarrassment of riches! Fortunately, M-theory came to save us.

Extra dimensions...
One of the most remarkable predictions of String Theory is that space-time has ten dimensions! At first sight, this may be seen as a reason to dismiss the theory altogether, as we obviously have only three dimensions of space and one of time. However, if we assume that six of these dimensions are curled up very tightly, then we may never be aware of their existence. Furthermore, having these so-called compact dimensions is very beneficial if String Theory is to describe a Theory of Everything. The idea is that degrees of freedom like the electric charge of an electron will then arise simply as motion in the extra compact directions! The principle that compact dimensions may lead to unifying theories is not new, but dates from the 1920's, since the theory of Kaluza and Klein. In a sense, String Theory is the ultimate Kaluza-Klein theory.

For simplicity, it is usually assumed that the extra dimensions are wrapped up on six circles. For realistic results they are treated as being wrapped up on mathematical elaborations known as Calabi-Yau Manifolds and Orbifolds.

M-theory
Apart from the fact that instead of one there are five different, healthy theories of strings (three superstrings and two heterotic strings) there was another difficulty in studying these theories: we did not have tools to explore the theory over all possible values of the parameters in the theory. Each theory was like a large planet of which we only knew a small island somewhere on the planet. But over the last four years, techniques were developed to explore the theories more thoroughly, in other words, to travel around the seas in each of those planets and find new islands. And only then it was realized that those five string theories are actually islands on the same planet, not different ones! Thus there is an underlying theory of which all string theories are only different aspects. This was called M-theory. The M might stand for Mother of all theories or Mystery, because the planet we call M-theory is still largely unexplored.

There is still a third possibility for the M in M-theory. One of the islands that was found on the M-theory planet corresponds to a theory that lives not in 10 but in 11 dimensions. This seems to be telling us that M-theory should be viewed as an 11 dimensional theory that looks 10 dimensional at some points in its space of parameters. Such a theory could have as a fundamental object a Membrane, as opposed to a string. Like a drinking straw seen at a distance, the membranes would look like strings when we curl the 11th dimension into a small circle.

Black Holes in M-theory
Black Holes have been studied for many years as configurations of spacetime in General Relativity, corresponding to very strong gravitational fields. But since we cannot build a consistent quantum theory from GR, several puzzles were raised concerning the microscopic physics of black holes. One of the most intriguing was related to the entropy of Black Holes. In thermodynamics, entropy is the quantity that measures the number of states of a system that look the same. A very untidy room has a large entropy, since one can move something on the floor from one side of the room to the other and no one will notice because of the mess - they are equivalent states. In a very tidy room, if you change anything it will be noticeable, since everything has its own place. So we associate entropy to disorder. Black Holes have a huge disorder. However, no one knew what the states associated to the entropy of the black hole were. The last four years brought great excitement in this area. Similar techniques to the ones used to find the islands of M-theory, allowed us to explain exactly what states correspond to the disorder of some black holes, and to explain using fundamental theory the thermodynamic properties that had been deduced previously using less direct arguments.

Many other problems are still open, but the application of string theory to the study of Black Holes promises to be one of the most interesting topics for the next few years.

Slavakion · 10-28-2004, 03:51 PM

Quote:

Originally Posted by mo42

There's also crazy stuff like gluons that I don't really understand.

Gluons are a type of quark. I think.

Let's head over to the Wikipedia.

muckluck · 10-28-2004, 06:33 PM

Matter is merely energy condensed into a slow vibration. So I'm guessing that all matter's building block is energy?

Slavakion · 10-29-2004, 02:29 AM

Energy and matter are equivalent. They are not the same, but can be exchanged for each other according to e=mc^2

Although matter is compacted energy, energy is expanded matter (expanded isn't really the word I'm looking for)

So what makes up energy?

10-29-2004, 06:42 AM

What if matter, energy and space were all different variations of the same thing? It's next to impossible to imagine any two without the other one. Matter curves space, forming gravity, and energy flows along geodesics on curved space. Space limits the interaction of matter (except in cases of quantum entanglement) according to distance and time (i.e. the speed of light)

These things seem so closely intertwined that it seems reasonable to assume that they are different aspects of a single fundamental thing. Doesn't it?

disgruntled · 10-29-2004, 07:55 AM

Remember that there are many different forms of energy and that its not always in the form of a light beam or a moving mass.

Slavakion · 10-29-2004, 06:43 PM

The point is that they're all energy, whether it's heat, sound, light or motion-related.

SPQR · 10-29-2004, 10:27 PM

I would probably answer "the Higgs boson."

Generally when we think of "matter" in the vernacular sense, we're takling about stuff with mass to it, like bowling balls or planets, but generally not massless stuff like "light" or "space." So what makes matter matter? What gives matter its mass? Enter the Higgs boson.

The Higgs boson is a still hypothetical (although maybe not for long!) particle that is said to give matter particles their mass. Some good descriptions of it can be found here: http://www.phy.uct.ac.za/courses/phy...icle/higgs.htm

Basically the Higgs boson can be pictured as a field in space that interacts with particles and makes them act like they have "mass" in the sense we're familiar with.

Here's another article that shows current efforts to detect the Higgs boson, which is also called the "god particle":
http://story.news.yahoo.com/news?tmp...cience_cern_dc

Hope this answer is something close to what you're looking for.

Rangsk · 11-07-2004, 02:55 AM

I don't know, what's the matter with you? Ok, bad joke.

Anyway, the way I think about is this - matter is simply a way of storing energy. You can actually create matter (for a very short amount of time) in particle accelerators. Some of the things created in particle accelerators are quite exotic too.

The reason we have a hard time perceiving that matter is energy is that we ourselves are matter.

10-20-2004, 08:01 PM	#1 (permalink)
MageB420666 <Insert wise statement here> Location: Hell if I know	Matter Ok I know this is probably a stupid question, but I am just getting tired of wondering about it so I thought I would ask. What is matter? I know mass is matter/volume, and I know what volume is, but what exactly is matter? I'm not talking, atoms, protons, neutron, electrons, and the really small things that make them up. I am talking about what the absolute building material is. What is the absolutely smallest particle there is made of? Do we even know? Am I just gonna have to keep getting agravated when I try to think about it? __________________ Apathy: The best outlook this side of I don't give a damn.

10-20-2004, 08:17 PM	#2 (permalink)
mo42 Insane Location: California	We don't know for sure what the smallest possible particle is. Right now we think it's quarks, which make up protons, neutrons, etc. There's also crazy stuff like gluons that I don't really understand. Your question bothers me also, since it's one of those fundamental things about the universe that remains a mystery. __________________ It's not getting what you want, it's wanting what you've got.

10-28-2004, 06:33 PM	#5 (permalink)
muckluck Psycho	Matter is merely energy condensed into a slow vibration. So I'm guessing that all matter's building block is energy? Last edited by muckluck; 10-28-2004 at 06:37 PM..

11-07-2004, 02:55 AM	#11 (permalink)
Rangsk Crazy Location: San Diego, CA	I don't know, what's the matter with you? Ok, bad joke. Anyway, the way I think about is this - matter is simply a way of storing energy. You can actually create matter (for a very short amount of time) in particle accelerators. Some of the things created in particle accelerators are quite exotic too. The reason we have a hard time perceiving that matter is energy is that we ourselves are matter. __________________ "Don't believe everything you read on the internet. Except this. Well, including this, I suppose." -- Douglas Adams

10-29-2004, 02:29 AM	#6 (permalink)
Slavakion Mjollnir Incarnate Location: Lost in thought	Energy and matter are equivalent. They are not the same, but can be exchanged for each other according to e=mc^2 Although matter is compacted energy, energy is expanded matter (expanded isn't really the word I'm looking for) So what makes up energy?

10-29-2004, 06:42 AM	#7 (permalink)
zen_tom Guest	What if matter, energy and space were all different variations of the same thing? It's next to impossible to imagine any two without the other one. Matter curves space, forming gravity, and energy flows along geodesics on curved space. Space limits the interaction of matter (except in cases of quantum entanglement) according to distance and time (i.e. the speed of light) These things seem so closely intertwined that it seems reasonable to assume that they are different aspects of a single fundamental thing. Doesn't it?

10-29-2004, 07:55 AM	#8 (permalink)
disgruntled Tilted Location: Vancouver BC	Remember that there are many different forms of energy and that its not always in the form of a light beam or a moving mass.

10-29-2004, 06:43 PM	#9 (permalink)
Slavakion Mjollnir Incarnate Location: Lost in thought	The point is that they're all energy, whether it's heat, sound, light or motion-related.

10-29-2004, 10:27 PM	#10 (permalink)
SPQR Upright	I would probably answer "the Higgs boson." Generally when we think of "matter" in the vernacular sense, we're takling about stuff with mass to it, like bowling balls or planets, but generally not massless stuff like "light" or "space." So what makes matter matter? What gives matter its mass? Enter the Higgs boson. The Higgs boson is a still hypothetical (although maybe not for long!) particle that is said to give matter particles their mass. Some good descriptions of it can be found here: http://www.phy.uct.ac.za/courses/phy...icle/higgs.htm Basically the Higgs boson can be pictured as a field in space that interacts with particles and makes them act like they have "mass" in the sense we're familiar with. Here's another article that shows current efforts to detect the Higgs boson, which is also called the "god particle": http://story.news.yahoo.com/news?tmp...cience_cern_dc Hope this answer is something close to what you're looking for.