Particle & String fundamentals

[baudrunner]

The following is the result of a bit of research I undertook today so as to establish a basis for the discussion of the lower-level topics related to the fundamentals whereof reality is constructed, wherein we usually find discrepency in fact when read from these forums. I am as guilty as any one of us. I did not write this myself as such, it is more or less a plagiarization from various informed sources and might even be outdated in parts, particularly with respect to M-theory (strings), however I have included only that which applies to general discussion and this bodes no serious transgression of contemporary thinking in my view, nor does it infringe on intellectual copyright since the knowledge upon which the sources are based is already in the public domain. This not only assures the accuracy of the information contained herein, it also frees me from committing completely to the facts as stated, since I did not write them.

In "particle physics", a particle is a subatomic object with definite mass and charge. Particle and anti-particle have identical mass and spin but opposite charges. Some electrically neutral bosons (force particles) are their own anti-particles.

The energy unit of particle physics is the electron volt (eV), the energy gained by one electron in crossing a potential difference of one volt. To get an idea of scale, if the protons and neutrons in a Helium atom were 10 cm. across, the electron would be .1 mm in size, and the entire atom would be 10 kilometres in diameter!

Electrically charged particles interact by exchanging photons. In strong 'color' interactions quarks interact by exchanging gluons. As quarks and gluons move apart the energy in the 'color' charge between them increases. This energy is eventually converted into additional quark and anti-quark pairs. These are then seen to combine into hadrons: mesons and baryons. Neutron beta decay results in the production of a proton, electron and an anti-neutrino via a mediating W- boson.

There are about 120 types of baryons, fermionic hadrons composed of three quarks, or three anti-quarks. The proton is the only baryon that is stable in isolation. Its basic structure is two up quarks and one down quark. The picture of a proton as made of three quarks is a gross simplification. For example, we know from measurements that in a high-momentum proton only about half the momentum is carried by quarks, the rest is carried by gluons.

String theory can be considered a particular kind of particle theory, in that its modes of excitation correspond to different particles. All these particles, which differ in spin and other quantum numbers, are related by a symmetry which reflects the properties of the string. The fundamental difference between a particle and a string is that a particle is a 0-dimensional object in space, with a 1-dimensional world-line describing its trajectory in spacetime, while a string is a (finite, open or closed) 1-dimensional object in space, which sweeps out a 2- dimensional world-sheet as it propagates through spacetime.

A string can be either open or closed, depending on whether it has 2 free ends (its boundary) or is a continuous ring (no boundary), respectively. The corresponding spacetime figure is then either a sheet or a tube (and their combinations, and topologically more complicated structures, when they interact).

Strings were originally intended to describe hadrons directly, since the observed spectrum and high-energy behavior of hadrons seems realizable only in a string framework. Certain string theories can thus be considered alternative and equivalent formulations of QCD (Quantum Chromo Dynamics), just as general field theories can be equivalently formulated either in terms of "fundamental" particles or in terms of the particles which arise as bound states. Due to matters of scale, a string formulation, where mesons are the fundamental fields, may be unavoidable. Thus, strings may be important for hadronic physics as well as for gravity and unified theories; however, string models seem to apply only to the latter, since they contain massless particles.

[baudrunner]

The following is a great link for those wanting to clarify their understanding of subjects and definitions pertaining to particle physics. It is a glossary of terms found at the Stanford Linear Accelerator Center web site,

http://www2.slac.stanford.edu/vvc/glossary.html#Beam

..from which you can link to the home page of the Stanford Linear Accelerator Center, operated by Stanford University and the U.S. Department of Energy,

http://www.slac.stanford.edu/

Reading from these pages is pretty much guaranteed to enhance one's understanding of particle physics.

[baudrunner]

Here is a quote from a link found at the Fermilab website,

http://www.fnal.gov/

Extra dimensions promise to solve many of current particle theory's nagging problems. They can explain the abundance of matter over antimatter, the surprisingly large number of elementary particles, and even dark matter—all phenomena that the Standard Model of particle physics fails to predict. This makes the concept of extra dimensions enticing. Yet in the empirical discipline of physics, extra dimensions face an embarrassing dilemma: so far, not a single shred of experimental evidence has been found to support their existence.

It's all just mathematics so far. However, the search goes on,

http://www.symmetrymag.org/cms/?pid=1000237

[Guille]

http://www.symmetrymag.org/cms/?pid=1000237

I liked the experiment which the stanford physicists are planning. It is at the very bottom of the article. What do you think about it, do you think it could find anything?

[baudrunner]

I personally don't think that results obtained from that experiment could ever prove conclusive because of the scale that they are analyzing and the extremely weak interactions that they are attempting to perceive. If a large flatbed truck carrying a part from the massive dynamo from a power plant project rolled by I suspect that they might observe the effects caused by that experience in their experiment and they might misinterpret the results. For that matter, the earthquake that caused the great Tsunami affected the gravitational pull of the earth ever so slightly, but it was also measurable, so seismic events would also affect observation.

In my opinion, the researchers are looking for gravity in the wrong place to begin with so that the proofs that they think they are getting would not reflect actuallity. They are working on the premise that gravitons exist as part of the structure of matter, whereas I think that gravitons exist as the structure of space, a very different theory altogether.

The example given in the article to demonstrate the weak force of gravity wherein the paper clip is picked up by a small magnet is just indicative of the small amount of space displaced by the paper clip compared to that of the dense mass of the small magnet, so the magnetic attraction of the magnet easily exceeds the gravitational attraction of the paper clip by many factors, and it might actually work in combination with its gravitational force in a form of constructive reinforcement.

[Guille]

I believe that the experiment is good for a good reason. Although I do think the scale they are looking at is not good, I don't think they are looking in the wrong place. The fact is that gravitons must exist as exactly betwen the mass and the spacetime. This premise allows that either gravitons and/or other bosons make up spacetime, or are between space time and matter. Because I use the word mass. Of course that gravitons are not in matter, they are in mass. Not exactly "in" mass, but either surrounding it, or as the edge of it.

[baudrunner]

This premise allows that either gravitons and/or other bosons make up spacetime, or are between space time and matter. Because I use the word mass. Of course that gravitons are not in matter, they are in mass. Not exactly "in" mass, but either surrounding it, or as the edge of it.

You're right about that. They are of such a nature that they can be said to permeate everything. I think that we agree in that they do not form a constituent component of any of the elements but that they yet keep the company of all the particles that do comprise them, effectively being displaced by those particles. The denser the object, the greater the overall displacement. That is and always has been exactly my way of thinking.

Here's an idea..

In that one must learn to not expect the expected, as often occurs in nature the exact opposite of a predicted outcome is usually encountered, it is also conceivable that gravity is a function of the absence of a homogeneous field of these gravitons/bosons. So that the more there are of these force particles in a given volume the weaker the force of gravity. Close to a large body such as a planet, the atmosphere displaces gravitons as well and we experience gravity for being on the surface, as well as atmospheric pressure. There are relatively far fewer gravitons at the bottom of the ocean, and a great deal of pressure because of the mass of the water. So what is mass, if it cannot be defined as the absence of gravitons? And gravity, if it also cannot be defined as an absence of gravitons? It's worth a good think.

[Guille]

You're right about that. They are of such a nature that they can be said to permeate everything. I think that we agree in that they do not form a constituent component of any of the elements but that they yet keep the company of all the particles that do comprise them, effectively being displaced by those particles. The denser the object, the greater the overall displacement. That is and always has been exactly my way of thinking.

And although we agree, I have a strong problem with this idea. This is: where is mass? How is mass? Is it contained all around the matter, in each particle? If so, where is the mass distributed around each particle? In this ultimate question I'm a refugee of string theory, I hope, momentarilly. It's the only idea that gives me any hint of how mass could be.

In that one must learn to not expect the expected, as often occurs in nature the exact opposite of a predicted outcome is usually encountered, it is also conceivable that gravity is a function of the absence of a homogeneous field of these gravitons/bosons. So that the more there are of these force particles in a given volume the weaker the force of gravity. Close to a large body such as a planet, the atmosphere displaces gravitons as well and we experience gravity for being on the surface, as well as atmospheric pressure. There are relatively far fewer gravitons at the bottom of the ocean, and a great deal of pressure because of the mass of the water. So what is mass, if it cannot be defined as the absence of gravitons? And gravity, if it also cannot be defined as an absence of gravitons? It's worth a good think.

This is interesting. But I believe in such case we wouldn't call gravitons gravitions, but another thing. And we would call graviton to whatever is where there is mass, spacetime curve. Weather it's a field, quantum-made, inhered in spacetime, or just absence... But I think this is not possible anyway for our universe. Because vacuum space means that there is no gravity, therefore it couldn't be that were there is no mass/matter, there is all the gravity there can be. By this discussion we're moving on from a more relativity vs qm synthesis into a maxwell vs newton synthesis. I believe that we cannot achieve the GUT or at least a basic explanation of the forces with the current forms of QM and of relativity. I'm working hard on a substitude of GR math, but the theory stays very similar, if I manage to solve the maxwell-newton problem, then the new version of GR that I make would be much more combatible with qm than Einstein's.

[baudrunner]

This is: where is mass? How is mass? Is it contained all around the matter, in each particle? If so, where is the mass distributed around each particle?

Relativity establishes that at light speed, an object has infinite mass and exists in a place where time stands still. Relativistic effects resulting from high velocity do not kick in appreciably until one approaches it very nearly. The angular spin momenta of particles approach this velocity and not only contributes to mass but time as well.

As for string theory, I see it as the fundamental law to which particles subscribe. We just can't analyze deeper than strings. After all, quarks and gluons etc have to be made of energy with a common origin and that origin is strings. m-theory fits in nicely with the beginnings of creation as I've described it in my TOE.

But I believe in such case we wouldn't call gravitons gravitons, but another thing.

I thought very much the same thing even as I was writing it, but I wrote it anyway because I thought the matter academic in a playful sort of way.

I don't think that Maxwell-Newton displace or exclude Relativity-QM in the least. The equation (m1m2)/d² applies regardless of the actual nature of the forces that bring two objects in space together.

[Guille]

Baud,

I didn't mean newton-maxwell to displace relativity-qm. Einstein developed SR to solve the fights N-M. 10 years later he developed GR to solve the problem SR-N (for SR had decided M was correct in the previous fight). Then we have GR-QM. But this problem has no slution, if it only took 10 years to solve the two biggest problems in physics until then to Einstein, how can it take 80 years and still not done to all the physicists? Their looking at the wrong problem. So we should just re-formulate GR math by developing a better result from classical physics and SR's interpretation and derivations from M, and all this done by knwoing that our result shoudl be combatible with QM. A new GR easy to unify with QM is a much more convincing idea than curent GR and QM unified.