Mordred

That is if you truly want to understand what drives space time expansion and contraction. [latex]Pv=nRT[/latex]

We don't necessarily expect to find these toy universes. They are used for a specific function. Lets run an example. "What would our universe look like with no cosmological constant?" How do we figure this out. Well we can take an equation that has been well tested or several equations we know work. Then we crunch the numbers to see what happens. The purpose is to allow one to fully understand what one specific influence changes. One of the best cosmology textbooks I ever read does this in painstakingly detail. She starts with explaining how the FLRW metric works. Then she describes all the single component universes. ( matter only,radiation only,Lambda only etc,) Then she does multi universe combinations. Finally arriving at our current universe. Due to that detail one truly can understand the term universe geometry and the relation to the ideal gas laws. We look into the universe it certainly doesn't look flat. In fact the observable universe looks round. So why does science say it's flat? The answer is the term flat is an energy density distribution term. Key note the FLRW metric is compatible with the Einstein field equations. By the way the textbook is Barbera Rydens "Introductory to Cosmology" So no we don't expect to find a Milne universe. Note in the case of the Milne universe Milne was unaware of GR and SR as noted in the wiki page I've never heard of the other two models Strange linked. There is another toy model universe that's handy to understand De-Sitter/anti-Desitter. http://en.m.wikipedia.org/wiki/De_Sitter_space I'm still hinting by the way. second clue look at equations of state cosmology google that term. Then look at the Einstein field equations and the FLRW metric. You should note all three involve the ideal gas laws. Then realize that so does GUT. You asked for a direction of study start with the gas laws It will make the EFE and FLRW metric easier to relate to. Ps don't forget the math Here is a universe geometry article I wrote http://cosmology101.wikidot.com/universe-geometry Page 2 http://cosmology101.wikidot.com/geometry-flrw-metric/

In some cases that happens. However the knowledge gained allows one to ask the same questions more accurately and concise. Without random misunderstandings interfering.

I've read the other books except the one by Schultz. Good review on em I agree with with Elfomatat's accessment. Lecture notes by Mathius Blau is also good if you have the math skills. See my signature. Least it's free lol. I linked a free one by Caroll already on this thread

In closing +1 lol long road been a pleasure. Not often you get posters in speculations to listen.

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)

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.

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/

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?

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

Thanks Phi didn't realize The link wasn't working.

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.

Yeesh your flying around in your spaceship. You want to calculate the force of gravity between your spaceship and the planet you are orbiting. What formula would you use? Lets ignore the second planet.

You described the radius relation of one body. I described the relation between two bodies. Two bodies have a shared center of mass. If you have two identically massive bodies the common center of gravity is half the distance between them. Not at the center of each body. In this case the force of gravity is strongest at the Common center of gravity. This point can be in open space Hence the references to the shell theorem and keplers laws

Yes your right on that but that's due to space time geometry. You need to use that calculation to know how strong a force of gravity is at a given radius so that you can use that value in your lorentz transformation.

Your post 89 specifically described two objects in space. With a gravitational force between them with a common center of mass. That Is the formula I provided. Here http://www.physicsclassroom.com/class/circles/Lesson-3/Newton-s-Law-of-Universal-Gravitation maybe this will be easier for you. My comments lol all I have stated is that you need to study and learn the math involved.

Lol what if you don't know the value of g then what? How would you calculate the force of g of say a planet with unknown mass?

Fine prove your model with the mathematics. According to the forum rules

Your post in 89 is a two body problem. You really need to learn math Here is the steps http://www.google.ca/url?sa=t&source=web&cd=2&ved=0CB4QFjAB&url=http%3A%2F%2Fwww.math.ksu.edu%2F~dbski%2Fwritings%2Fplanetary.pdf&rct=j&q=keplers%20laws%20pdf&ei=ikCuVP2LMo3_yQSEo4G4Cw&usg=AFQjCNERKXhUjcq8DIiKhxLobebgqftHtw&sig2=JHBfI2EpZAe8PolcTP6sAA&bvm=bv.83134100,d.aWw Your 89 post regarding your test of the force of gravity at the center of mass can be calculated using the method of that link

If I didn't understand physics how would I know what factors apply to your theory to post those articles in the first place. They do relate to your model. Considering the variety of questions you posted throughout this thread. Yes that is what that equation is used for Google universal law of gravity for details http://en.m.wikipedia.org/wiki/Newton's_law_of_universal_gravitation

Went and re-read your 89 post. You included the center of mass component in your beginning descriptive. However the wormhole aspect needs some thought. In answer to the rate that gravity decreases [latex] f=\frac{GMm}{r^2}[/latex] And please don't be insulting I am spending considerable time trying to help you

The shell theorem and the center of mass. I saw that problem in post 89. It's correctable via your second to last post

If you read peer reviewed papers model proposals are always compared to the pre existing models. After all the purpose of a model is to improve our understanding. If it doesn't improve our understanding then it's no good.

You might want to look up shell theorem with regards to your model http://en.m.wikipedia.org/wiki/Shell_theorem I didn't say my model prevents yours from working. I was able to disprove my model idea. You will need to try to do the same to yours. Model development. Premise of the model. Mathematical proof of the model Testing and supportive evidence of a model Disproving a model. A model only lasts if it cannot be proven wrong. So you need to examine how it may be proven wrong and figure out how to correct it.

I do get it. Does that mean you stop there and not learn how to show that to others with the tools of mathematics? After all you want to improve your model and ideas. Lets take an example. For several years I tried to replace the cosmological constant using thermodynamics basically a high density region will naturally spread out to a lower density by increasing its volume. Sounds perfectly plausible. We see this in our everyday experiences. Good example is a sail or how temperature spreads out. If I had stopped there I would have never learned that this doesn't work for the cosmological constant. It's not homogeneous and isotropic nor can it be constant. So I tried other methods and metrics to make it work. Including ADS/CFT. Never did succeed. So I know that idea cannot work. The problem your going to have with this is Keplers laws do work. Let's explain we have the sun and the Earth. Each has its own gravitational field. In Keplers laws the two bodies orbit the center of mass. Luckily the Sun is far more massive than the Earth so the center of mass is the sun. In other system such as two similar suns this isn't the case both suns orbit the center of mass.