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Posted (edited)

 

I cam across the following example (again) the other day:

 

Imagine two people standing on the equator some distance apart. They both start walking due north. They both think they are walking in a straight line with no forces acting on them but they still get closer together.

 

Now, you might be thinking that the Earth is playing the role of the "fabric" of space time. But we don't need the Earth there in this example. It just makes it clearer.

 

We can start with two people located on the circumference of an imaginary sphere. They both move in a "straight line" along great circles defined by this imaginary sphere. They will get closer together, even though there are no forces, just the curved coordinate system.

That's an excellent example

Here is one from Wikipedia

 

 

"In the theory of relativity, it is convenient to express results in terms of a spacetime coordinate system relative to an implied observer. In many (but not all) coordinate systems, an event is specified by one time coordinate and three spatial coordinates. The time specified by the time coordinate is referred to as coordinate time to distinguish it from proper time."

 

http://en.m.wikipedia.org/wiki/Coordinate_time

Unfortunately coordinate space on wiki isn't as clear.

 

http://en.m.wikipedia.org/wiki/Real_coordinate_space

 

However if you read it. You will note it mentions the minkowskii distance.

 

Taking those two links you can see that metrics of GR is a coordinate metric that describes space time as a coordinate space + coordinate time.

 

 

Found this handy site that simplifies the Einstein field equations.

http://math.ucr.edu/home/baez/einstein/einstein.html

Edited by Mordred
Posted

Found this handy site that simplifies the Einstein field equations.

http://math.ucr.edu/home/baez/einstein/einstein.html

 

Excellent! I have seen some of that before, but not all of it. Good old John Baez.

 

 

This equation says that positive energy density and positive pressure curve spacetime in a way that makes a freely falling ball of point particles tend to shrink. Since img19.gif and we are working in units where img3.gif, ordinary mass density counts as a form of energy density. Thus a massive object will make a swarm of freely falling particles at rest around it start to shrink. In short: gravity attracts.

 

(This weeks piece of trivia: he is cousin to Joan Baez, the singer.)

Only if gravitons have anti-gravity property, and if they as particles are not able to form blobs.

 

Gravitons are massless and therefore travel at the speed of light.

 

As such, they are as likely to form "blobs" as light is (i.e. not at all).

BTW, Kramer, you should read that article by John Baez. It gives a reasonably non-technical description of how gravity works and how exactly the same thing accounts for the expansion of space (aka big bang).

Posted

 

Actually it was the "photons have a front and back" bit I was curious about. (The bit you describe sounds like the photoelectric effect, which was one of the first bits of evidence for quatum theory - got young Albert his Nobel Prize.)

 

 

In prinicple, yes.

If we can clear the room of all EMF and EM charge, now lets clear that room of spacetime and mass...not too hard to get rid of all the mass, but i need to hear what we can use to rid ourselves of all the spacetime filling the room...

 

I dont think of spacetime as fabric, just as I dont think of the EMF as fabric...I do consider that EMF is THERE or NOT....if something is there, and then can be taken away, it is something...Im not defining the nature of WHAT it is at this point, Only that it is something...

 

I do understand that GR is classical model, which essentially means, it can all be figured with math and geometry, which do not need any THING to create their effects...But it does not stipulate that THINGS cannot be involved in creating the geometry...

In this your not alone a lot of people feel space itself must be some form of material or form of fabric. This is a common problem. It doesn't help when you hear the term the fabric of space time often used. Even by professional physicists. This is where all the aether theories keep cropping up.

 

Part of the problem is energy does not exist on its own. It is a property of particles. This includes fields. As such would also the a gravity field. Which would require a graviton.

 

The term space is just the amount of volume available. Space time just adds the time component. The two are inseparable in many ways one and the same as shown by GR.

 

The thing to realize is that gravity can only communicate to particles.

 

However the average density of space would give roughly the equivelent of 4 to 5 protons per cubic meter. That's a lot of volume with no particles in it.

 

The common argument is to try to fill that up with virtual particles. Zero point energy due to the Heisenburg uncertainty principle is commonly quoted. Aka Casimiir effect.

 

I've always found it best to simply think of space time as a coordinate map. This coordinate map tells particles how to move. Matter tells the coordinate map how to curve.

Aether describes a different thoery of spacetime proposed by some guy...Although my thoery does include a property of spacetime that equates into energy that is meant to replace the cosmo constant and free of us dark matter and dark energy, it is not akin to the aether directly...

 

A photo has no mass...are you still calling it a particle? Gravity definitely works with photons...I can see that you are a particle fan...but I am a waveparticle fan...

 

Since I have a new theory, not all the old definitions "work" for me...this has been an issue between us ever since this post began...I am here talking about new perspectives and your only response is to ask me to see it in terms of the old definitions...It does help me see GR better and better...but, youre not putting any real effort into seeing the topic through the perspective I offer...which would be the only purpose of exploring a new topic or perspective...

 

 

Posted

i need to hear what we can use to rid ourselves of all the spacetime filling the room...

 

Reduce the size to zero, is the only thing I can think of.

 

Actually, the same thing is true of the EM field: if you screen the room you won't get rid of the field, just sets its value to zero. This is more akin to making sure the space-time in the room is not curved.

 

 

But it does not stipulate that THINGS cannot be involved in creating the geometry.

 

I don't see why. (Have a read of the John Baez thing: even if you skip the maths you should get something out of it.)

Posted

 

Reduce the size to zero, is the only thing I can think of.

 

Actually, the same thing is true of the EM field: if you screen the room you won't get rid of the field, just sets its value to zero. This is more akin to making sure the space-time in the room is not curved.

 

 

I don't see why. (Have a read of the John Baez thing: even if you skip the maths you should get something out of it.)

Well, all im doing right now is trying to convince those that see EMF and spacetime as "nothing" to begin to see it as something...anything that would put it beyond the barriers of being truly "nothing"...Can nothing be molded? can nothing have its value set to zero? can nothing have properties that effect something? Getting people over the hump to see that spacetime is something is my first order of business...once it is something, i can start talking about how that some interacts and how it has energy...

Lets say that spacetime is nothing...meaning that there is no spacetime at all...do these 2 statements mean the same thing? I think they do and have no conflicts.

 

theres just one issue...there is spacetime...for those who say its nothing, they really have a major issue to deal with...

To say that there is spacetime, but it is nothing, seems to ring of practical impossibility...

Posted

What makes you think we think of the EMF and what occupies the volume of space time as nothing?. No matter how dense you make matter space still exists between particles. This includes a virtual particle field of photons. Aka the basis of field theory.

 

I mentioned the ideal gas laws before. The ideal gas laws are inclusive in the Einstien field equations with an association with the stress energy tensor.

 

No matter how dense you try to make space time there is still space between particles.

 

Remember the term space must apply equally for ALL size scales.

 

So how can we possibly describe space as anything other than volume?

Posted

To say that there is spacetime, but it is nothing, seems to ring of practical impossibility...

 

The thing is the model, the theory, doesn't require these things to be real or to be made of something. As such, saying that they are made of something (which has no effect on the theory) contradicts Occam's Razor. If someone comes up with a new theory that requires space-time or the EM field to have some physical properties (mass, tensile strength, flavour, whatever) then that is a different thing.

 

Features aren't added to theories to satisfy someone's aesthetic sense (after all, someone else might just as well say, "its not gluons but neutrinos/Higgs bosons/photons" - all of which have been suggested in the same way) but because the theory doesn't work without them.

 

If you want to say that space-time is gluons then you need to develop a theory that requires spacetime to be made of gluons - not just the existing theory with gluons stuck on the side like an unnecessary wart.

Posted

I know geometery doesnt require anything to exist, and to perform its functions in thoery...but, in this case, although it doesnt require it, does not mean its not there...


We all need to get a government grant so we can sit around talking about gravity theory all day! and not have to work...ha


My theory states the spacetime is a dimensional stacking of fields...each field has its own interactions...its just the gluon field that lends itself to compression,,,


If you go read about the gluon field you will find that it is always present in spacetime...it is the only form of vacuum energy that we have ever detected...


Posted

although it doesnt require it, does not mean its not there...

 

But this is one of the fundamental aspects of science: if it is undetectable, it is assumed not to exist. (After all, science is about the objectively testable and measurable, not belief in the undetectable.)

 

For example, there is a thing called Lorentz Ether Theory which is indistinguishable from Special Relativity in all ways: they both predict exactly the same results, there is no experiment that can tell them apart. The only difference is that LET includes a mysterious "thing" called ether while SR does not. As this ether makes no perceptible difference to anything, no one considers it to be real and the theory is of no more than historical interest.

Posted

Here is a quote on fields.

 

So: quantum field theory comes from starting with a theory of fields, and applying the rules of quantum mechanics. A field is simply a mathematical object that is defined by its value at every point in space and time. (As opposed to a particle, which has one position and no reality anywhere else.) For simplicity lets think about a scalar field, which is one that simply has a value, rather than also having a direction..

 

in other words it is also a coordinate map of interactions. Each coordinate will have a calculated value of influence. Note the part about particles

 

that was a quote from Sean Carroll

 

http://www.preposterousuniverse.com/blog/2013/06/20/how-quantum-field-theory-becomes-effective/

Posted

 

The thing is the model, the theory, doesn't require these things to be real or to be made of something. As such, saying that they are made of something (which has no effect on the theory) contradicts Occam's Razor. If someone comes up with a new theory that requires space-time or the EM field to have some physical properties (mass, tensile strength, flavour, whatever) then that is a different thing.

 

Features aren't added to theories to satisfy someone's aesthetic sense (after all, someone else might just as well say, "its not gluons but neutrinos/Higgs bosons/photons" - all of which have been suggested in the same way) but because the theory doesn't work without them.

 

If you want to say that space-time is gluons then you need to develop a theory that requires spacetime to be made of gluons - not just the existing theory with gluons stuck on the side like an unnecessary wart.

I know it is not required for a model or theory...the universe where space time does exist however, it needs causes in order to have effects...

 

They didnt add dark matter and energy to GR to satisfy it's "aesthetics"? It seems so...

 

My gluons are not warts...ha....they just happen to be that which gives spacetime the impetus for the curvature of the thoeretical curves of GR....from theory to reality takes a few jumps

Posted

Then your going to need something other than fields to do it with. Fields is a mathematical treatment of scalar,vector tensor etc spaces. It is a coordinate treatment.

Posted

Strange, I dont know if you saw this in an earlier post, but Im gonna do the quick gloun gravity explanation again...really short and sweet as possible...

Protons and neutrons need gluon field strength to support the quark interactions happening within them...

So the gluon field, without the presense of any quarks or hadrons, is still there...its always there and permeates all of spacetime...it takes energy to always be there...

Lets say I have some empty space time and I start filling it with matter...so, lots of protons, neutrons, other hadrons and quarks all need the energy of the gluon field to do their thing (QCD)...

In my theory, there is a point where you can compress enough matter, filled with protons and neutrons, into that volume of spacetime and it does not have the gluon field energy to support all those reactions...it does take energy to compress the matter together that much...and now it will take more energy from the gluon field to support but, but the gluon energy from that volume of spacetime isnt enough...

The gluon filed then has to use energy from a different volume of spacetime and it begins to use the energy from the gluon field that surrounds it...since it cannot take energy from the matter it is supporting, and the matter it is supporting is using all its energy, the gluon filed absorbs energy from the unused spacetime around it...

This would create a "draw" of gluon field energy into the center of the mass from all the space surrounding it...


Then your going to need something other than fields to do it with. Fields is a mathematical treatment of scalar,vector tensor etc spaces. It is a coordinate treatment.

How many more times will you make this statement? :) I know your perspective on this, I can assure you...


The theory can act like a computer screen..When your graphics card is pushed to its limits and can no longer keep up, what happens? a lag is created...the screen slows down (time) and often you lose resolution too (space)...if your computer screen could shrink, in order to need less graphics coverage, that would also help...and if your computer was hooked to a network and could borrow processing power from other computers in the network when its demands were being tested (gravity) that would be very cool...


So really, I was just trying to give a physical explanation for what drives the changing of the bahaviors of spacetime to account for the fact that the geomtery was being created...

I do see Mordreds constant point...Ha...lets make a thoery called "Mordreds Constant Point" where he states over and over that spacetime needs only coodinates to exist...ha...kinda cute...maybe ill buy the URL

I think his point really becomes that the geometry is created by the vectors and tensors of the particles that enter spacetime...they have motions and energies and the geometry created by THEM, is that which then effects THEM, is caused by THEIR influence...individually and as a group...vectors and tensors are awesome concepts...

Which speaks so highly of our state as humans in this whole thing...and even speaks to determinism vs predeterminism...

Ive been floating on air for the last two days...this forum has been the best thing for me since that last chic who was into BDSM...

Posted (edited)

I'm still trying to get you to see the math.

 

Let's take a field we will start with a scalar field.

 

Assign a scalar value to every point in space. Call this scalar space. Then introduce a particle. You pick one. The particle will influence The scalar space values according to its range of influence. As this is a scalar field we can describe this as a change in temperature. Temperature being scalar.

 

Now let's step forward. Assign a base line vector value for every point in vector space. Now introduce a particle. The particles influence will interact with a vector influence upon the vector corrdinates.

 

So I ask you how is this any different from your issues with GR in terms of causes?

 

What I did was describe in simple terms the scalar field and the vector field. The gluon field works the same way with the appropriate number of degrees of freedom. (Each color interaction etc)

Edited by Mordred
Posted (edited)

Ill admit my theory is poop...as amazing as the 20 year journey of spending every toilet and driving moment with my thoughts in visions of bent foam and particles of light...as much as it has done for me as a person to apply myself to the very borders of my own conceptions with nothing but knowledge as the prize...feeling the unquenchable thirst that is NEEDING to know and understand and surrounding myself with people who know that PAIN...it has all been awesome...my life would have been a bore this far without these desires driving my thoughts...

Ill find my next theory...realize the problems and revise them...or maybe Ill start searching for dark matter...to release this idea and notion feels ok now


I'm still trying to get you to see the math.

Let's take a field we will start with a scalar field.

Assign a scalar value to every point in space. Call this scalar space. Then introduce a particle. You pick one. The particle will influence The scalar space values according to its range of influence. As this is a scalar field we can describe this as a change in temperature. Temperature being scalar.

Now let's step forward. Assign a base line vector value for every point in vector space. Now introduce a particle. The particles influence will interact with a vector influence upon the vector corrdinates.

So I ask you how is this any different from your issues with GR in terms of causes?

What I did was describe in simple terms the scalar field and the vector field. The gluon field works the same way with the appropriate number of degrees of freedom. (Each color interaction etc)

And as I end, Mordred finally stuns the crowd with an explanation in his own words that makes really good sense and I could relate to and understand...well said...LOL! I was begging you to do that many pages ago...

Dont you ever go hidin your own expressions ever again, young man...for no reason! You are here to express...and you finally did it! Its akin to scientific intimacy issues and finally letting down your gaurd...thanks man :)

Edited by JohnSSM
Posted

"I don't think your characterization of black holes smashing space time out of existence is correct..."

 

If you need to be harsher because "theres NO WAY my characterization of black holes smashing space time out of existance is correct"...Then do it, otherwise you leave me thinking that you arent for sure...

 

If you want to...no pressure to be harsher...my point is...it didnt sound that solid and i wouldnt want you to spare me for my feelings sake...

 

That's a combination of rebutting a vague (i.e. not mathematically rigorous claim) and not being all that familiar with the GR of black holes.

 

You cant decrease the strength of magnets by heating them? I thought it was possible...I might be thinking superconductivty with magnets and heat...

 

You can, but the mechanism is thermal motion of the atoms, destroying the domains. It's not an interaction with the fields.

Posted

 

That's a combination of rebutting a vague (i.e. not mathematically rigorous claim) and not being all that familiar with the GR of black holes.

 

 

You can, but the mechanism is thermal motion of the atoms, destroying the domains. It's not an interaction with the fields.

If the gridlines are closer together near massive objects, its taking it as close as one can for black holes...and the closing of it becomes the event horizon...I thought it nice since it gives a really good explanation of why nothing can radiate from a black hole...not even light can pass a barrier where there is no spacetime to pass through...or so I claim within the bounds of foam theory

 

That's a combination of rebutting a vague (i.e. not mathematically rigorous claim) and not being all that familiar with the GR of black holes.

 

 

You can, but the mechanism is thermal motion of the atoms, destroying the domains. It's not an interaction with the fields.

I looked deeper into it today as well...The heat and magnetic fields...and youre almost right but you have seem to forgotten what I realized today...

 

When you heat a magnet, add energy, the aligned magnetic properties fade away with the excitement of the bits...and heres the thing...that object is creating the magnetic field. Lets say you had a room that you could cut off from all outside EMF...and you bring a magnet into the room, the magnet is what creates the EMF in that room...its the 2 poles interacting with each other....you dont need two magnets to create an EMF...so if particle physics is at work, and you heat a magnet,you are right...but you do lose the field...Do you think magnetic fields are there before the presense of the magnet? Thats exaclty how I was seeing gravity...Believing that space time has its own impetus of existance...but it doesnt...space time geomtery in GR is definitely created by the masses themselves...which is to say the same thing about the empty room as deep empty space...there is no curvature until you bring a mass into deep space...I ope we agree on this or my undestanding is still off

Posted (edited)

Believing that space time has its own impetus of existance...but it doesnt...space time geomtery in GR is definitely created by the masses themselves...which is to say the same thing about the empty room as deep empty space...there is no curvature until you bring a mass into deep space...

 

This is slightly ambiguous. At the beginning it sounds like you are saying that space-time doesn't exist until you introduce mass, at the end it sounds as if you are just saying that there is no curvature until you introduce mass.

 

The first is definitely not true, as it is entirely possible to solve the Einstein Field Equations for a universe containing no mass or energy.

 

Perhaps surprisingly, the latter isn't actually true either; space time can have some intrinsic curvature even in the absence of mass and energy.

 

Which is rather like the EM field having a non-zero value even in the absence of charge. (Which it does.)

Edited by Strange
Posted (edited)

My theory suggests that massive geometrical collapse (or massive gravity) is what breaks the gloun field...and if I wanted to make it paralell to the rules of GR, I would have to claim gravity itself is the impetus of the gluon field...

If Magnet (charge) is to EMF
then
Mass (gravity) is to Gluon field

and I was not prepared to make that claim after understanding fields and their sources so I put foam theory on a low back burner...


 

This is slightly ambiguous. At the beginning it sounds like you are saying that space-time doesn't exist until you introduce mass, at the end it sounds as if you are just saying that there is no curvature until you introduce mass.

 

The first is definitely not true, as it is entirely possible to solve the Einstein Field Equations for a universe containing no mass or energy.

 

Perhaps surprisingly, the latter isn't actually true either; space time can have some intrinsic curvature even in the absence of mass and energy.

 

Which is rather like the EM field having a non-zero value even in the absence of charge. (Which it does.)

Yknow what...i was right in both claims...youre gonna have to think for a minute though...Do you know of a universe that doesnt have any mass? Of course not..now...envision a universe, with GR, without any mass...there is no space and there is no universe....So yes...mass does create space...but its been created for like 14 billion years now...now the mass that moves through space seems not to create it, but it was allready there...I hope youre getting this...


I truly truly truly understand vectoring and tensor systems now...and I was right about motion...its just an energy level with vector...nothing moves...but it does curve spacetime


was there any spatial volume before the big bang?


The blank slate for a universe, would not be empty space any more than it would be a huge chuck of material with no space....


Actually...it was a huge chunk of material with no space...of course...the laws had not been turned on yet...


If nothing is moving, there is no space...

Edited by JohnSSM
Posted

Youll have to discuss it as you understand it. If you have the proof right there in those links, then it should be easy since you know it so well.

When discussing matters that aren't speculative, Why would there be any discussion? We should just have forum posts full of links to answers and questions...

I take lots of time to type and explain and think...I would rather have you send me private messages to a bunch of links...if everyone did the same, there would be no talking and I could just google the topic entries to find reading material... But im for more than reading material...I am here, at a forum, mostly for discussion...

Don't be offended when I ignore those postings from now on...Im sorry, im not interested I those links right now...

Posted

The problem with gluons being the source of gravity is that gluons don't interact via the electroweak force, and e.g. electrons are affected by gravity. Continuing on with that approach is really a nonstarter.



When discussing matters that aren't speculative, Why would there be any discussion? We should just have forum posts full of links to answers and questions...

 

Understanding something often involves more that simply being given an answer to a question.


If the gridlines are closer together near massive objects, its taking it as close as one can for black holes...and the closing of it becomes the event horizon...I thought it nice since it gives a really good explanation of why nothing can radiate from a black hole...not even light can pass a barrier where there is no spacetime to pass through...or so I claim within the bounds of foam theory

 

The gridlines wouldn't be infinitely close together at the event horizon. At the singularity perhaps, but that's where GR fails, and newtonian gravity blows up at r=0 as well.

Posted

Youll have to discuss it as you understand it. If you have the proof right there in those links, then it should be easy since you know it so well.

 

I have already said that there are solutions to the equations of GR that describe universe with no mass or energy, but still with space and with curvature. I'm not sure what else you expect me to say. I only provided the links so you wouldn't think I was just making it up.

 

Obviously, you can choose not to read them (a couple of them are pretty mathematical) but there is some interesting stuff in there.

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