M-Theory is a theory which 'combines' the five superstring theories

[marcus]

http://arxiv.org/abs/physics/0309104 Democritus as Taoist
.

you say the atomist tradition that led to John Dalton should be called
"neo-atomism" (idea of matter consisting of types of identical atom, in integer proportions)
and that Democritus did not has this idea, so did not begin the neo-atomist tradition

where does this tradition, that led to Dalton, begin? how far is it traced back?

 

[arivero]

where does this tradition, that led to Dalton, begin? how far is it traced back?

I'd say, at some point between Aristotle and Epicurus, when the property of "size" is moved from space to the atom. It is the main tradition preserved; it is used by instance by Copernicus in comparing the relative sizes of Earth and Solar System "as an atom to the whole body". And it is surely the one that Gassendi receives, but I can not tell for sure because I have not read him.

The other tradition is darker, but the insight for recovering the word "indivisible" (atom) in the geometric process comes from Galileo, according a partly preserved exchange with Cavalieri.

 

[Spin_Network]

Then what do you mean by singularity. My understanding is that a singularity is where you have infinite value only at one particular point. So if the whole universe consisted of only one particular point, then there is no comparing the value of a field with another point which does not exist yet.

I wonder how you would mark the differences between manifolds of slightly different differential sizes. It seems to me that if you don't have things like particles or strings yet, then there would be some sort of invariance with size, no means of distinguishing the quality or value of empty but growing universes. What's this called, conformal invariance? You'd have to know which point was the starting point and which points in the differential region were not the singualar point. But I think that the idea of a manifold growing from a singularity is that after it grows, you can no longer tell which point is the center. It seems then that you have some other invariant properties such that each point is just as likely to be the center as any other point. The laws of physics are the same at every point in space; there is then no preferential frame of reference for any measurable thing. And if that is so, then how do you even measure the size of the universe as it grows? Maybe that is why it may seem that space is broken into portions of the plank volumes. Below such scales there is no distinctions that can be made, no "measureable" observables.

Looks like a reformation?:http://arxiv.org/abs/gr-qc/0508045

good paper!

 

[Mike2]

Looks like a reformation?:http://arxiv.org/abs/gr-qc/0508045

good paper!

Thanks, that was interesting. I'll have to keep it for reference.

My point, however, was that if there is no particles in the universe, then it becomes impossible to measure how big the universe is. Size then becomes an arbitrary coordinate system on a manifold. Nor is time something that can be measured because it becomes impossible to say how long things have been as they are if there are no things (particles). So it is impossible to say if the universe bounced or banged or emerged. It would seem that at a time before particles (if such ever existed) physics was invariant with respect to a metric and was invariant with respect to bangs and bounces, etc. Or can you suppose a continuous field (not a particle field) whose density is physical?

 

[mykingdomforapurpose]

distance has been shown to be arbitry when we transformed the five sting theories and realized they where all the same. there is a sixth older equation that we can also transform to the string theories and it used an 11 dimention frame work. these transformations led to the brain theories where the 10D string theories are all interchangable even with an 11D frame. so scientists felt the 10D frames where small parts of the 11D. distance was found arbitry when you calculate stings of diffrent length travling in circles. the longer the string the more it winds onto the circle and then travling on the same size cicle covers a massive amount of extra distance.

when considering spacetime backgrounds i use the projector model. where the projector is the stings/brans and the picture is our universe. its a good representation as it alows a universe with no real anything that we can still explore. the vibrations of all those stings crate one cohesive picture and that is all of us, everything projected as one picture. now layer the projections so that there is a picture of everything that will ever happen, like a storybook of all that will ever be. time is the dimensional reality of turning pages. the information is all there, everything has already happened but as you read you get this sensation of moving through the book and things seem to happen as you turn the pages. alas no.

 

[rain.w]

when considering spacetime backgrounds i use the projector model. where the projector is the stings/brans and the picture is our universe. its a good representation as it alows a universe with no real anything that we can still explore. the vibrations of all those stings crate one cohesive picture and that is all of us, everything projected as one picture. now layer the projections so that there is a picture of everything that will ever happen, like a storybook of all that will ever be. time is the dimensional reality of turning pages. the information is all there, everything has already happened but as you read you get this sensation of moving through the book and things seem to happen as you turn the pages. alas no.

Oh, mykingdomforapurpose, I just hold the same view! except I prefer the term "layer model" to your "projector model". I think every layer emerged along the time line means a new/extra dimention above the previous layer...

 

[janusz]

How can gravity be both a curved spacetime and a particle moving through spacetime simultaneously? If gravitons are particles moving through a background spacetime, then where did the background come from? Even if it doesn't matter what the background is (it still results in the same physics), you still seem to need a background in order to calculate the particle properties. Where did that background come from? Is there a 5th force which does bend the background spacetime? If it doesn't matter what the background is in order to obtain the particle properties, then the particle properties cannot depend on the background, so the background, likewise, cannot be influenced by the particles, right?

I have similar problem,particle as a point of relation to expanding space is not passive .Matter seems to be negative and contractive but spacetime positive and repulsive coming from within a particle.Is it possible that this repulsive and expanding force is the source of gravity and string of energy is balancing portion of energy on the framework of the spacetime?
Why movement curve the spacetime in the direction of movement longitudinal mass,time and length?
Why term for acceleration on the line and gravity for spherical acceleration?
What about violation speed when speeding body reaching light speed and need constant acceleration to keep the same speed? In empty space just once given the speed stay invariant- is it for certain value mass a limit?Does inertia has limit in the speed closed to the speed of light?
Why exist term background in physics,where every thing is strictly interactive? Is it this background in within us, the atom enlarged is ghostly place?
Why time is always presented as the line,to have chance to write sf? What about it curl up with dimension and time as flat surface,rubber sheet grabbing particle in movement ,speeding to light limit and stretching its fabric to cumulate violation of time,imagine atomic clock with radioactive uranium still ticking whereas its brothers twins from radioactive family long ago decayed.I can imagine sheet of paper and passing the pencil,but pencil is not existent only the hole changing properties,in human minds the pencil represent history and the future but is illusive.
Space time energy must be positive--because it is coming - potential difference?
Never background.otherwise we are mostly background.Thank you.
Janusz Melbourne Australia

 

[janusz]

All the difference in the world between particles flying around in a curved, fixed, background space on the one hand, and particles causing the spacetime to bend, while it causes them to curve in their paths. Background independent means that the space is in the foreground, taking part in the physics, and dynamically altering and being altered.

At this point this forum look like dead,cold desolated place.I went through the threads and I noticed that I could be placed into the class of "discovery channel" in which i not to be classified.I came to the forum with the bunch of weird question,with the quest to complete or build the view of my Universe.
Just for example in the book Universe in the nut shell - S Hawking maybe 20 times spoke about his contribution to the science .My contribution can be only if I hold the answer provider for the minute in the spacetime of his PC and protect him this way from the car crash next minute.So I'm expecting nothing accept good answer.I love Einstein imaginary world and I'm not going demolish anything in the system,just get alight dark patches in my mind regarding this world.
In the Universe in the nut shell - author describing the world two mixed ways; classical when he say in the one line that gravity bend the light in the black hole vicinity and relativity way in the next line then curvature of the space bend the light hence a confusion of light having mass.This is contribution of the great master Jedi to my building workbench.And it is tones of other examples .
Having 45 years 20 years ago I switched myself to the relativity mode and I found myself having gaps in understanding it and only that's why I'm here...
I come back to the thought experiment I have given before but from different perspective.My kids asked me why the same 1 kg of sugar weights on Jupiter more? Say - my answer in relativity mode sounds like this; because the curvature of the Earth give this 1kg mass or acceleration 1g on the Moon roughly 1/4 g and in the spacetime between Earth and Moon 1kg of white sugar for instance has its own curvature of spacetime of let's guess of 0.0000157g.OK? So I told kids one made bad investment by putting all package on the moon.They asked why it is still the same 1kg.
Let's say another thought experiment,atom of hydrogen and speed it up keeping its matter property.When it reach the speed closed to speed of light the relative length increase ,is not the illusion for hydrogen atom ,it lives in different universe and other dimension flatten,so it is long like galaxy -time tick,1 second taking to travel through the Galaxy,still it needs the travel for the rest of Universe to complete the trip.In that speed takes maybe 100000years.Lets speed it up then.We come according to Einstein that even the whole energy of the Universe we put into expenses to defeat of the resistens and still it did not get into the speed of the light.We couldn't flatten enough width,height and time to having only length like the light has...loose characteristic of matter.
At first our atom does not need extra energy it works with inertia but in the certain point the spacetime became resistent and we have to invest more and more energy to push it forward.It can change into energy itself but in the thought experiment I want to preserve the characteristic of the matter or rather curvature of space? Where is this resistent barrier for mass of the atom of hydrogen?
Another example is the light in the spacetime,its travels having only length with no time characteristic so should theoretically come back everytime,constantly and coming within background radiation,where is the rest? It disperse in the expansion,it means for me {sorry} some of the grains of the space are not touched by traveling light beam,when come from A point to B on the remote areas of the Universe it not finishing in the B because B has been replaced by pop up fresh B2 =C. ,so in this case light behave like having curvature - little bit of time? - and too can't escape of the system .
And the last question ;in the theoretical physics string is the lowest part of the matter so the next step down is the space itself,expanding ,dynamic not stagnant space within the matter.Is it possible to create mathematical model of the hatching point or grain of the spacetime 3 dementional with expanding like umbrella surface of penetrating time with the dynamic,oscillating ring of the string on it,grains emits another grains? Passive grains and active grains?
There is no point of the rest in the universe,all matter have the curvature,spacetime is manipulated by movement and masses.
Why to close the picture this expansion is not a reason for gravity,why we talk about vacuum and on other hand that skillfully we explain 11 dimension and not seeing beauty of our magnificent 4 in theory of relativity.
Movement like negligence of the grains,and spherical acceleration as negligence of the grains in rescistance for expansion and very closed to it resistance to speeding matter violation speed ending inertia?
Thank you
Jan Maszczyszyn - nobody Melbourne Australia

 

[selfAdjoint]

I come back to the thought experiment I have given before but from different perspective.My kids asked me why the same 1 kg of sugar weights on Jupiter more? Say - my answer in relativity mode sounds like this; because the curvature of the Earth give this 1kg mass or acceleration 1g on the Moon roughly 1/4 g and in the spacetime between Earth and Moon 1kg of white sugar for instance has its own curvature of spacetime of let's guess of 0.0000157g.OK? So I told kids one made bad investment by putting all package on the moon.They asked why it is still the same 1kg.

It isn't the curvature of the Earth (that sphere we live on) that makes the acceleration, it's the curvature of the spacetime near the earth. This makes the shortest path for the Kg. of sugar curved (it's just straight down in 3-space, but curved when you include the time dimension, which is experienced in 3-space as acceleration). And aren't your kids right? What we want from a Kg. of sugar is a certain amount of sweetenig power, not what it shows on a spring scale. This is why the metric Kg is better than the avoirdupois pound; it is a measure of mass, which is the same on the Earth, Moon, and Jupiter, and even in free fall, while the pound is a measure of force which is not constant even on Earth (lighter at the equater than at the poles due to centrifugal force).

Let's say another thought experiment,atom of hydrogen and speed it up keeping its matter property.When it reach the speed closed to speed of light the relative length increase ,is not the illusion for hydrogen atom ,it lives in different universe and other dimension flatten,so it is long like galaxy -time tick,1 second taking to travel through the Galaxy,still it needs the travel for the rest of Universe to complete the trip.In that speed takes maybe 100000years.Lets speed it up then.We come according to Einstein that even the whole energy of the Universe we put into expenses to defeat of the resistens and still it did not get into the speed of the light.We couldn't flatten enough

The atom in its own rest frame does not notice any dilation effects. Its physics is just as good as some observer who sees it as traveling fast. All inertial frames see the same physics internally, is one of the two postulates of relativity.

And the relativistic effect on length is to shrink it. If two observers see each other moving with 86% of the speed of light, they will measure each other's lengths as half of their own.

 

[praveen27net]

Membrane Theory

hai all,
actuall i am computer sciec student , but i am interested in knowing abt 11 th Dimention and M-theory . Can anybody gives me right link to know abt it thoroughly.

 

[the blob inc]

i think vectors are wrong

 

[janusz]

It isn't the curvature of the Earth (that sphere we live on) that makes the acceleration, it's the curvature of the spacetime near the earth. This makes the shortest path for the Kg. of sugar curved (it's just straight down in 3-space, but curved when you include the time dimension, which is experienced in 3-space as acceleration). And aren't your kids right? What we want from a Kg. of sugar is a certain amount of sweetenig power, not what it shows on a spring scale. This is why the metric Kg is better than the avoirdupois pound; it is a measure of mass, which is the same on the Earth, Moon, and Jupiter, and even in free fall, while the pound is a measure of force which is not constant even on Earth (lighter at the equater than at the poles due to centrifugal force).
So,where the curvature of Earth starts? I meant something else,spacetime as the entity,as the third observer.I have given this primitive example to form my question about space as a frame not a background...



The atom in its own rest frame does not notice any dilation effects. Its physics is just as good as some observer who sees it as traveling fast. All inertial frames see the same physics internally, is one of the two postulates of relativity.

And the relativistic effect on length is to shrink it. If two observers see each other moving with 86% of the speed of light, they will measure each other's lengths as half of their own.

And again,the spacetime as the third observer supplying the mater of framing of dimension and in the case of accelerating atom having not enough power to push the time into the reality of the atom.For the spacetime is it atom stretched half way trough Galaxy?
Thank You very much for your time .

 

[CJames]

As I recall, the idea of the big bang came from the observation that the universe we can see is expanding. It seems logical that if you could follow the paths of all the particles in the universe back in time, you would find that they had a common origin, a single point, at which space and time all the universe we know occupied a singularity. It isn't practical to actually follow all the particles back in time, but we can do calculations to show what might result.

There was some argument at first about whether the particles would actually come to a singularity. Maybe they just came into some close region of points, not actually a single point. But IIRC this argument was resolved in favor of the singularity. Gravitational forces would become immense, and no surface irregularities could endure. The universe, run backwards, would have to collapse into a perfect sphere, which would then have to collapse into a single point.

There are two definitions here of singuarity. Basically a singularity is just something that starts pumping out infinities. Physicists don't like singularities and usually interpret them as meaning something isn't quite complete, as do pretty much all other sciences.

In any case as I know it the current model of cosmology is something like this. The universe is infinite in space and time. That is, it will never collapse again, and it has no measureable size. I don't think this is totally confirmed, but I was under the impression that measurements of the cosmic background radiation had lead to this conclusion. The singularity that the universe supposedly sprang from, which is ultimately something that needs to be explained away, is infinite in size and density, rather than infinitely small and infinitely dense.

On the other hand, it is still possible that the universe is closed and will eventually collapse again. In this case the original singularity was in fact a point. However do NOT think of the universe after this as being spherical. The universe has no center and no edge. Instead, think of this model of the universe as though it were the SURFACE of a balloon, except 3-dimensional rather than 2-dimensional. I realize some of this may be over your head and for that I appologize.