Ask any question you want about Physics

originally posted by: pfishy

originally posted by: ImaFungi
a reply to: pfishy

When a bowling ball is dropped off the top of a skyscraper;

According to modern physics best understanding of reality, and the aspect of reality we term 'gravity';

What physically is forcing the ball to move?



Does EM radiation (which from now on for convenience sake I will refer to as; light) 'created' 'in/as' the sun move as particles from the location of the suns body, to the location of the earths body? As if the sun was 'throwing baseballs towards earth', as an analogy, to the sun 'throwing light towards earth'?

Ok, I have to admit that the phrasing of the second part of your question is a bit confusing, but let's go ahead and see where we can get with this. I'll give you my answer, then you give me yours and we can see if they differ.
The bowling ball is acting on potential energy, due to the gravitational field of the Earth exerting a constant pull on it. The forces acting upon it are momentum energy and gravity. Now, I suspect that this answer won't satisfy you, so you can elaborate on your question in your response.
Photons are emitting by excited electrons moving between energy states. The direction in which any given photon moves is determined by the local charge field of the electron. So, as they are generated in the Sun's core, and spend around 10,000 years bouncing off protons and such, they work their way to the surface and travel in whatever direction the ended up leaving the core in. Until they are absorbed or reflected. But no, they are not baseballs. Baseballs are mostly composed of baryonic matter. Photons are not. They are most likely massless. (Current experiments have set an upper limit for the mass of a photon, but have not shown them to have mass. We just know that if they do, it is less than the limits of that our equipment can detect. And it would be so small as to be negligible in pretty much every significant way.)
Ok, I know that you are actually asking about the nature of the photon itself, as well as its creation and direction of travel. Photons are quanta of energy. They have properties of both particles and waves. They travel and act like a wave until interactions with matter collapse their waveform and they isolate as a single particle. When they are emitting by electrons, they are moving a relativistic speed. Slightly less than 300,000 km/sec. Passing through matter can slow this speed, but it resumes full speed in a vacuum. As for the reason behind the constant speed in a vacuum, even after being slowed by matter, I do not have a solid explanation. I'm not a physicist.
But the collapse from wave to particle is evident in the fact that an electron can absorb a photon. Electrons are many times smaller than any wavelength of light. This is why we use electron microscopy. Electrons can provide a resolution that light cannot. But if light were purely waves, the photon would only lose a small amount of energy when it encountered an electron. Much like a wave at the shore of the ocean does not cease to exist because part of it hits the piles supporting a pier, or a person standing in the water.

To answer your question light always moves at C. When we say it slows down in a medium well what we should say is ot takes more time. What happens in say glass when a photon hits the glass it is absorbed than re transmitted. This continues until it exits the final photon that exits the glass is not the same one that entered. This same thing happens in a mirror light is absorbed and it is transmitted. Basically energy goes in the atom ans it releases it again trying to get back to its ground state.

So light will always move at C. Thus is because it's massless any particle with zero mass will move at C. If we took something with Mass and we want it to move at C. We a simply swap mass for energy meaning as mass decreases velocity will increase its a trade off.

Now that you mention it, I do believe that I have read that before. Thanks for the info.

originally posted by: dragonridr
To answer your question light always moves at C. When we say it slows down in a medium well what we should say is ot takes more time. What happens in say glass when a photon hits the glass it is absorbed than re transmitted. This continues until it exits the final photon that exits the glass is not the same one that entered. This same thing happens in a mirror light is absorbed and it is transmitted. Basically energy goes in the atom ans it releases it again trying to get back to its ground state.

You were doing OK until you said "energy goes in the atom and it releases it again", since it's pretty easy to show that can't be what happens because atoms have discrete energy states and we don't see this discrete behavior in the transmission of light through glass. It's actually absorbed by the lattice structure, and re-emitted from that, not from individual atoms:

Do Photons Move Slower in a Solid Medium?

A common explanation that has been provided is that a photon moving through the material still moves at the speed of c, but when it encounters the atom of the material, it is absorbed by the atom via an atomic transition. After a very slight delay, a photon is then re-emitted. This explanation is incorrect and inconsistent with empirical observations. If this is what actually occurs, then the absorption spectrum will be discrete because atoms have only discrete energy states. Yet, in glass for example, we see almost the whole visible spectrum being transmitted with no discrete disruption in the measured speed. In fact, the index of refraction (which reflects the speed of light through that medium) varies continuously, rather than abruptly, with the frequency of light.

Secondly, if that assertion is true, then the index of refraction would ONLY depend on the type of atom in the material, and nothing else, since the atom is responsible for the absorption of the photon. Again, if this is true, then we see a problem when we apply this to carbon, let's say. The index of refraction of graphite and diamond are different from each other. Yet, both are made up of carbon atoms. In fact, if we look at graphite alone, the index of refraction is different along different crystal directions. Obviously, materials with identical atoms can have different index of refraction. So it points to the evidence that it may have nothing to do with an "atomic transition".

When atoms and molecules form a solid, they start to lose most of their individual identity and form a "collective behavior" with other atoms. It is as the result of this collective behavior that one obtains a metal, insulator, semiconductor, etc. Almost all of the properties of solids that we are familiar with are the results of the collective properties of the solid as a whole, not the properties of the individual atoms. The same applies to how a photon moves through a solid.

A solid has a network of ions and electrons fixed in a "lattice". Think of this as a network of balls connected to each other by springs. Because of this, they have what is known as "collective vibrational modes", often called phonons. These are quanta of lattice vibrations, similar to photons being the quanta of EM radiation. It is these vibrational modes that can absorb a photon. So when a photon encounters a solid, and it can interact with an available phonon mode (i.e. something similar to a resonance condition), this photon can be absorbed by the solid and then converted to heat (it is the energy of these vibrations or phonons that we commonly refer to as heat). The solid is then opaque to this particular photon (i.e. at that frequency). Now, unlike the atomic orbitals, the phonon spectrum can be broad and continuous over a large frequency range. That is why all materials have a "bandwidth" of transmission or absorption. The width here depends on how wide the phonon spectrum is.

On the other hand, if a photon has an energy beyond the phonon spectrum, then while it can still cause a disturbance of the lattice ions, the solid cannot sustain this vibration, because the phonon mode isn't available. This is similar to trying to oscillate something at a different frequency than the resonance frequency. So the lattice does not absorb this photon and it is re-emitted but with a very slight delay. This, naively, is the origin of the apparent slowdown of the light speed in the material. The emitted photon may encounter other lattice ions as it makes its way through the material and this accumulate the delay.

Moral of the story: the properties of a solid that we are familiar with have more to do with the "collective" behavior of a large number of atoms interacting with each other. In most cases, these do not reflect the properties of the individual, isolated atoms.

originally posted by: pfishy
Now that you mention it, I do believe that I have read that before. Thanks for the info.

You probably did, but it may have been wrong too. This idea about an atom in glass absorbing and re-emitting photons is a popular misconception. It's interesting how the behavior of large groups of atoms can differ from the behavior of individual atoms.

I wasn't going to say it, but this is correct. It's delayed by the plasmon deformation of the electrons around the atom. They recoil and then spring back to normal and the photon is re-emitted.

Unlike absorption and re-emission by electron orbital, a plasmon deformation retains the phase and direction of the photon (mostly), so everything transparent isn't cloudy like ground glass.

It should be obvious that it's not a re-emission, because the phase and direction of a spontaneously emitted transition photon are random. This doesn't count for stimulated emissions, though.

eta: it doesn't require a collection, either, a single neutral atom will do it to whatever photons it encounters, thus you get some slowing (and dispersion) with interstellar gas, it just takes a lot more travel time to add up...

originally posted by: ImaFungi
In what you know of graviton theory; We drop a bowling ball off of a skyscraper, according to what you know, is it proposed that, the bowling ball falls, because graviton particles push and/or pull it down?

Like I said, I don't know much about gravitons, because not only are they only hypothetical, but we know that there are problems trying to treat virtual gravitons the way we might treat virtual photons. So, I'm afraid until we have a workable theory of quantum gravity, or some alternate theory along those lines, we don't have good answers to this question.

This explains some of the issues we face with trying to use gravitons to explain interactions:

Graviton problems

You don't have to accept that gravity is a "force" in order to believe that gravitons might exist. According to QM, anything that behaves like a harmonic oscillator has discrete energy levels, as I said in part 1. General relativity allows gravitational waves, ripples in the geometry of spacetime which travel at the speed of light. Under a certain definition of gravitational energy (a tricky subject), the wave can be said to carry energy. If QM is ever successfully applied to GR, it seems sensible to expect that these oscillations will also possess discrete "gravitational energies," corresponding to different numbers of gravitons.

Quantum gravity is not yet a complete, established theory, so gravitons are still speculative. It is also unlikely that individual gravitons will be detected any time in the near future.

Furthermore, it is not at all clear that it will be useful to think of gravitational "forces," such as the one that sticks you to the earth's surface, as mediated by virtual gravitons. The notion of virtual particles mediating static forces comes from perturbation theory, and if there is one thing we know about quantum gravity, it's that the usual way of doing perturbation theory doesn't work.

Quantum field theory is plagued with infinities, which show up in diagrams in which virtual particles go in closed loops. Normally these infinities can be gotten rid of by "renormalization," in which infinite "counterterms" cancel the infinite parts of the diagrams, leaving finite results for experimentally observable quantities. Renormalization works for QED and the other field theories used to describe particle interactions, but it fails when applied to gravity. Graviton loops generate an infinite family of counterterms. The theory ends up with an infinite number of free parameters, and it's no theory at all. Other approaches to quantum gravity are needed, and they might not describe static fields with virtual gravitons.

a reply to: Arbitrageur

Does the same mass planet have a different value force of gravity depending on how fast it was rotating?

First I would also ask, if the mass of a planet increases as its rotational velocity increases (relativistic mass would increase?), and therefore does that not answer my original question.

If there were 100 trials; Starting with a planet moving linear through space without rotation. And then a planet moving linear through space with minimal rotation. Then next trial a little faster rotation. Next trial a little faster rotation. Until the maximum rotation before the planet could not be held together (which I presume is a very lot) would be reached. Approaching more maximum rotational velocities, would eventually loop over to being opposite of gravity and eject objects off of the surface (like a play ground merry go round, spun faster and faster until children a tossed off).

Or, there is such faith in the concept that gravity operates purely by geometry of physical slopes, that no matter how fast the body was rotating (especially if relatively, this would make the slopes steeper the faster it rotated, or if it would only be pseudo steeper, or...ahh, perhaps my intuition is correct that the massive body in a sense grabs hold of the gravity medium which slopes, and twists it in its direction of rotation, and so the faster the body rotated, the faster the slopes of the gravity field would rotate, making it like trying to climb up a slide that was laterally moving quickly as a treadmill).

I have stuck with my intuition I remember I must have brought it up a year ago to you, my initial concern of what should be our inability to ignore the unavoidable cosmically fast and multiple movements of the bodies we study the gravity of, and then state awareness of the fundamental nature of gravity, that there might be significant difference between a bodies gravity force while purely absolutely stationary and away from all other mass. And a bodies gravity force that is moving linear in increasing trials of velocity, and a bodies gravity force that is moving linear and rotating in increasing trials of velocity.

Mainly. Because I dont see how a stationary body, would cause the gravity medium surrounding it, to slope consistently (I understand square of distance, meaning not consistently in the purest sense, as in linear, but square of distance is still a consistency), If the body is just sitting perfectly stationary, what would cause the gravity medium that is just beyond the square of the distance, (which extends to all throughout the rest of the universe, so its all that collective mass, verse the bodies mass, which displaces the gravity medium mass from its local vicinity) from not caving in and pushing back and successfully overriding the effect beyond the body of the body. Oh boy perhaps thats why and how movement exists in the first place! (because you love to look for my weakest point and attack me there, disregard that last sentence, as all would and should acknowledge it as, although potentially very interesting material to discuss, the least fleshed out and contented of what I am putting forth in this response).

So. Lets imagine a perfect spherical body the size of earth away from any other masses. Lets say the planet starts to move or to make things less controversial, is and has been moving through space. From our vantage point as observers, over time, we can establish the actual direction of the planets movement (by determining which direction we ourselves have to move in, in order to continually be closest to the planet), then we label a big arrow on the front of the planet, front denoting the direction the planet is heading, we label a big square on the back of the planet, the planet is not rotating at all.

You and I are now standing on the square. I take a baseball in my hand and throw it straight up, which is the exact opposite direction of the frontal arrow we have labeled. The baseball leaves all contact with the body itself (if atmosphere plays any or a large role in this conceptual discussion, we may discuss it, or consider that we do two trials; one in which the planet possess earths atmosphere; one trial in which the planet possess absolutely no gas, just the pure hard material surface).

So; it seems to me, if you were to argue that the ball would come back to me, considering all the details of the situation (the earths linear movement), you will do so by saying that there exists physical material called the gravity field, which forces the ball to come back to the planet.

But normally; when the gravity medium is 'undisturbed by mass', mass can 'pass right through it'; and now that the gravity medium is disturbed by mass, a mass such as ball, cannot just pass right through it.

Well first lets think of the planet just existing perfectly at rest, amidst the gravity medium; it is posited that it will cause the gravity medium to 'tense up' beyond just the bodies surface; that is what square of distance insinuates, that the planet does not remove all the gravity medium material that would be occupying the area of its massive take up, and then all that gravity medium material does not just pool up right outside the surface of the planet. Cant you see the intrigue there? That there apparently exists, a material medium, and a material called massive planet, which is 'attached' and passes through the material medium of gravity field, but in this scenario it is not passing through, it is perfectly motionless, and its simply existing amidst the gravity material medium, forces the surrounding material medium, at a seemingly astonishing distance from its actual body surface, to tense up, and remain a strict metal like erection. It does not fold under 'non' pressure, the non pressure of at an increasing distance from the actual body, where the actual body is not, the gravity material does not cave in...what the heck!!

That is one of the insights that led me to think that the motions we know to exist of our relation with planetary bodies (that they are not purely stationary) may have something to do with our realization of the existence of what we term gravity.

(you know, why Einstein saw the link between inertia and gravity, I think because if we did this experiment from the front arrow of the planet, we could see why the ball might come back. And then further more, with rotation of the planet and an arcing travel, we might still again see how throwing the ball at any point, the ball being so small compared to the surface area, it would be quickly caught up with by the movement of the planet in the mean time of air time of ball...maybe)

However we come to decide upon and realize the nature of that stationary planet and its effect on the surrounding material gravity medium w/ trials of increasing velocity, would slope of medium truly (which means physically, which means really) increase in angle as the velocity of a planet continually increased? Do you imagine a ball in a bubble and the area of the bubble remains constant as ball increases velocity? Or as velocity increases, does the bubble increase, or at least angle of bubbles walls?

a reply to: Arbitrageur

Much easier to explain it that way than I don't have to explain the electron lattice. Basically with refraction you can see the charge travel though glass. Or in certain experiments stop it But bottom line it's still atoms absorbing and releasing energy. So Your Kind Of Being Picky.

a reply to: ImaFungi

Doesn't general relativity answer your question? Gravity is space-time warp which is described by classical mechanics (we don't have a quantum theory).

In your example above, you say that the planet is at rest with no other mass or force around it. But yet you say it's moving. What's moving it?

originally posted by: Phantom423
a reply to: ImaFungi

Doesn't general relativity answer your question? Gravity is space-time warp which is described by classical mechanics (we don't have a quantum theory).

In your example above, you say that the planet is at rest with no other mass or force around it. But yet you say it's moving. What's moving it?

I said a lot of thing. You are mistaken. From the start to finish of that post of mine I cover a lot of different potentials. You are mixing one area of moment of thought experiment I said, with another. If you go back and read line by line and see how the lines and thoughts connect, and then end, and new but related thoughts and lines continue, you should be able to notice where, why and how you are mistaken.

I asked very specific questions. Does general relativity submit an experiment to test the gravity of a planet that is absolutely motionless? If it is thought that we are seeking the fundamental laws of physics. If we then think that we have approached and are approaching fundamental laws, we should be able to use these fundamental laws we have found, to use one any conceivable scenario using our knowledge of matter. Thus, I present scenarios in which one, who may know the approached fundamental laws of gravity, is asked to attempt to utilize their knowledge of fundamental law, on a physical scenario which is untestable, such as a completely stationary planet, to see if any further knowledge and ignorance of knowledge can be gleamed from this combative effort.

originally posted by: ImaFungi
Cant you see the intrigue there?

The intrigue for me is in trying to understand exactly why the presence of mass has the gravitational effect it does. But once we accept that it does (for reasons we can't fully explain, hence why we call gravitation a "fundamental" interaction), the math of relativity defines the expected gravitational effects of the scenarios you describe.

I don't think a "bubble" is such a good way to look at gravity, but rather the "well" concept with varying slopes is a better visualization tool, since it doesn't infer any boundary like a "bubble" does. The gravitational effect just gets gradually weaker with distance, such that as the distance approaches infinity the gravitational effect approaches zero.

psas.pdx.edu...

originally posted by: dragonridr
a reply to: Arbitrageur

Much easier to explain it that way than I don't have to explain the electron lattice. Basically with refraction you can see the charge travel though glass. Or in certain experiments stop it But bottom line it's still atoms absorbing and releasing energy. So Your Kind Of Being Picky.

It was the singular atom you referenced that I felt needed correction. If you had used atoms in plural as you just did, I probably wouldn't have said anything.

a reply to: Arbitrageur

What about the implied extra dimensions that string theory suggests, do they actually exist?

originally posted by: dragonridr

With this you also learn about monopoles everything in the universe is controlled by spin. Including why matter can't occupy the same space. Every question you ask involves spin. Once you realize electrons spin all the time it should start to make sense. They don't vibrate like I've seen you say.

I admit, this is a difficult topic. Only because from what I have read it is both said and said not that fundamental particle spin is and is not 'really spin'.

Not so much just the fact that a sphere with markings on it to a stationary observer who can read those markings can determine that the sphere is spinning;

But that, it is thought that a sphere (for simplicity circumstances, any 3d shape can be appropriated into a sphere, I suppose any 3d shape can be appropriated to any shape, but why does the sphere seem to me to be so perfectly balanced, I suppose the cube too, yes the pyramid too, but the sphere seems naturally most balanced, no points of contention) with markings on it that a stationary observer can read these markings, that say marking marked '1', in some of the particles must spin around more than once before the sphere and the system surrounding it, to be equal to as it was before it started spinning.

Some of them only need 180 degree spin before its equal, which suggests that the object, is qualitatively equal in its front and back, although potentially there may be some differences about its sides.

I posit that it must be the way in which the particle in question is attached to the material mediums which surround it, that would cause a greater than 1 spin.

That is; if marking '1' is facing us, and the particle begins to spin, and it spins 360 degrees and marking 1 is facing us, yet we can not say that the system is equal to as it was before it started spinning, that it must spin again; that what comes to my mind as being the only reason that this could be possible, is the way in which this particle is attached to the material medium which surrounds it;

so that each degree it is turning (however we would like to argue of the discreteness of fluidity of motion from degree to degree) it is effecting the field it is attached to, so that by the time it has rotated 360 degrees, which in classical realm we would say,

'the system should be the same as when it started, the particle has turned full circle; why and how could anything have changed?!?';

I would say; 'why and how could anything have changed? it seems it must be that as the particle turned, it also turned the local field it is attached to with it, in a twisted manner, and might we then be forced to consider that there must be something significant and mechanical, in some breaking point sense, that if the system is not equal to as it were when we started the particles rotation after 360 degrees, but if it continues another 180 or 360 degrees until then aha the system is as it were when it started, that the medium attached to the particle, reaches some breaking point, in which it is snapped back into original place,

or even to make crude (but potentially righteously beautiful) analogy as to say the main particle in question is as a gear, and the medium which surrounds it is many little gears, and when the bigger gear is turned 360 degrees, the little gears do not represent the system that existed prior to the big gears turning, but the big gear must be turned an extra 180 or another 360 ( spin 1.5 spin 2) until the system appears as it did prior.

The spin creates a magnetic field In a magnet or a copper wire.

Explain me this How come electrons always repulse; but the main reason magnets work, and half of the way in which magnet works means anything is that, magnets attract; is due to the electrons. In magnets, are electrons attracting electrons?

Two magnets in a vacuum, magnets are made up of quarks and electrons, or lets say, neutrons protons and electrons. These two magnets are separate objects. The neutrons, protons and electrons that make up the magnet, are moving in certain ways. You say the electron is always spinning (real spin, or is there or is there not a different between a baseball spinning, and an electron spinning; I say there is no difference but that fundamental particle spin simply and merely denotes a certain extra connotation to the meaning of rotational spin, due to the intimate nature of supreme particle and supreme field at that fundamental level). Well, it is possible the electron is doing its cloud dance around the nucleus as well as potentially its mysterious and arguable infinitely pure and precise rotation, and it is possible all of these true factors contribute to what I am asking, but I am asking how all these factors contribute to what I am about to ask here;

Two magnets in a vacuum. separate objects. The parts that make up these separate objects are moving in certain ways. It is the way in which the parts of these separate objects move, and how these parts movements interact with the material field (force field) which exists between inside and all around them. My intuition was so right, I am brilliant and great, you have wasted a great deal of my time as two years ago or more I had these marvelous insights and paths towards extreme pure truth. You have time and time again ignored the content of my posts, just so you can feel good about yourself pretending that you are smarter than me, pretending, or perhaps you actually are truly so ignorant as to think that I was not smart or did not know the things you think I did not know, any way you treated me wrongly time and time again, not remembering all the things I had said over the past two years, making you if not a schilly troll, a pompous self congratulating ignoramus, purely seeking the pleasure of your own back patting.

Anyway, you deserve that and more so just ignore what I just said there and focus on the substance of my comments, something you have not done for all the time we have been, blegh, acquaintances.

Mechanically, physically, really; what are the parts that make up each magnet, doing to the mechanical, physical, real, material medium which surrounds the parts that make up each magnet, so that the separate objects of magnets, move toward one another (which is termed attraction)?

a reply to: pfishy

Those were separate questions, not meant to be related. Merely two fundamental questions I have been seeking the deepest insight too for the past few years, which I have been doing so because I know that know human truly comprehends the true fundamental truth of these insights. I brought them up to by pass your insulting belief in the need to start from the conditions which you felt we needed to agree on, to assume I am so far below you in understanding that we need to start from positions which are taught to 13 year olds.

The first question was regarding the fundamental nature of gravity.

The second question was regarding the fundamental nature of light.

Lets you and I focus on light, since if you will read this thread you will see more recently I attempted to dig as deep as possible into gravity with a lengthy series of questions.

As for light, I am wondering about the supposed particle nature, the meaning of masslessness, how it is related to if not entirely actually the phenomenon of electro magnetism itself in every way. And, in what physical form light exists in before it is propagated. Which requires the intimate romance with the ultimate axiom of something and nothing, to avoid cheating, by cheating I mean lying to oneself, by lying to oneself I mean being wrong, I mean being ignorant. Such as to say 'a photon actually exists, and then when it enters into a lattice the photon which is not nothing, 'disappears' and becomes 'energy' which is not nothing, but could sort of be nothing, in the sense that 'movement' is 'real' but not something'. I can further expand upon all this if you dont fully grasp any aspect of what I have just said.

a reply to: Arbitrageur

Try to answer my questions about throwing the baseball from the square mark off the back of the earth without movement, what physically would keep the ball from continuing off into space?

Do you understand why the slope goes off into infinity?

It is because the gravity medium material is given relativistic momentum by mass exerting its force on it, and there is no equal and opposite force which cancels out the momentum the mass gives that gravity medium material so it continues moving (thus the idea of gravity waves); which is the idea of sections of the gravity medium moving (as sections of the water medium move and can be called waves), though the gravity medium is a 3d medium, as the water medium is, but we are familiar with water waves on the surface of the 3d medium, and we are (I should speak for myself, I am) bewildered as to how waves function (~deep?) inside/within a 3d medium, which is why everyone panics and gets scared about talking about compression waves and polarity and hates the word aether because it reminds them of magic and they put on a suit and tie and look in the mirror as the gate keepers of intelligence and logic and reason and wouldnt be able to look at themselves as the giants who look down at the savage magicians of the past

I only used bubble, because I like to get to as close to truth as possible, and a 3 dimensional well around an object might be something of a bubble.

a reply to: ImaFungi

I understand - I just picked up on that one scenario where the object is at rest with no mass or applied force.

So if the object is at rest, the object is an inertial reference frame with no reference i.e. no outside force or reference to act on it. So F = ma where F and a are usually vector quantities, and F = mg where g is acceleration due to gravity are meaningless. So gravity has to = 0. It takes two to tango to have gravity - can't think of any other scenario for an isolated object in an adiabatic system with 0 references. Even if there was an isolated photon which has no mass, there would be some interaction to induce some small gravitational effect (I think). But in a world consisting of a single object, I think gravity has to = 0.

originally posted by: ImaFungi
a reply to: Arbitrageur

Try to answer my questions about throwing the baseball from the square mark off the back of the earth without movement, what physically would keep the ball from continuing off into space?

We've sent the Voyager spacecraft off into space, and other probes also. As the link I posted calculated, it takes a velocity of 11,181 m/s or greater to escape Earth's gravity. So any velocity less than that would keep the ball from continuing away from Earth forever, since it wouldn't have the necessary velocity to escape Earths gravity.

I only used bubble, because I like to get to as close to truth as possible, and a 3 dimensional well around an object might be something of a bubble.

Bubbles have defined edges The gravitational well diagram I posted has no defined edge. I'm sorry you can't see why bubbles aren't a very accurate representation, but it should be obvious from studying the well diagram and seeing the difficulty of drawing a bubble which shows the same thing. I don't know how you could do it.

originally posted by: andy06shake
a reply to: Arbitrageur

What about the implied extra dimensions that string theory suggests, do they actually exist?

I keep seeing string theorists say they are going to figure out ways to experimentally test string theory, but I'm not seeing the experiments proving it. Maybe with the LHC upgrade we will see some results that give us some clues one way or another, but they are saying it will really take until 2016 at the earliest to get enough statistics analyzed in the latest experiments there.

a reply to: Arbitrageur

Could you escape it if we just had a massive ladder?.
Or a space elevator?.

a reply to: boymonkey74
A ladder won't do it, you need velocity.

Even the astronauts in the ISS are still subject to about 90% of Earth's gravity, don't let the so-called "zero-G" fool you into thinking otherwise.

originally posted by: Phantom423
a reply to: ImaFungi

I understand - I just picked up on that one scenario where the object is at rest with no mass or applied force.

So if the object is at rest, the object is an inertial reference frame with no reference i.e. no outside force or reference to act on it. So F = ma where F and a are usually vector quantities, and F = mg where g is acceleration due to gravity are meaningless. So gravity has to = 0. It takes two to tango to have gravity - can't think of any other scenario for an isolated object in an adiabatic system with 0 references. Even if there was an isolated photon which has no mass, there would be some interaction to induce some small gravitational effect (I think). But in a world consisting of a single object, I think gravity has to = 0.

Well is it not that the only way in which an object exists at all (especially as in my example I was using a perfectly spherical earth sized object, referring to it as, planet) is due to what is termed 'gravity'? So that planet cannot exist and there exist 'no gravity', right?

Also, the way in which gravity exists, is due to the material medium which surrounds objects/other material/other material mediums/other styles of mass;

So yes I recall in one train of thought I expressed the hypothetically scenario of taking what we know of as matter/mass/planet and placing it in a hypothetical realm in which it was the only 'something' that existed amidst an area of absolute nothingness;

But the related train of thought, was the planet, existing far away from galaxies, though in this universal system of universe;

To posit the stationary planet, existing amidst the gravity material medium. And different trialed motive versions therein.

originally posted by: Arbitrageur

We've sent the Voyager spacecraft off into space, and other probes also. As the link I posted calculated, it takes a velocity of 11,181 m/s or greater to escape Earth's gravity. So any velocity less than that would keep the ball from continuing away from Earth forever, since it wouldn't have the necessary velocity to escape Earths gravity.

But that is relative to the earths rotation and linear velocity through space and the fact the earth has atmosphere. If you did read my response, I was asking to compare the understanding of mechanism of gravity, to different scenarios; such as, motionless earth in absolute nothing space; motionless earth amidst gravity medium but far away from other masses; 100s or 1000s of trials and how the results would differ of the different possible linear velocities of earth and how gravity is altered therein; 100s or 1000s of trials and how the results would differ of doing the same increasing with each trial linear velocity, as well as an increase with each trial of rotational velocity; and perhaps even how gravity value alters starting from stationary earth, with slightly increased rotational velocity without linear travel over trials.

Also, when things escape earths gravity, do they not enter into the suns gravity well, as we are always amidst suns gravity well?

This relates to my thoughts, on the nature of the slope of the well;

If a baseball cannot be thrown off earth because every point on earth you throw the baseball away from the surface of earth, the ball is rolling up and then rolling down a slope/well wall we cannot see but must be there;

Ok, well a younger me would have asked; why doesnt neptune roll down the hill towards the sun; and the answer is because the sun is always moving; so this is the classic image of wake, neptune, the planets are surfing the suns wave/wake;

But then I ask;

Related to the well and the bubble, 3 dimensional wake? The sun is a sphere, it must effect the medium all around itself equally (intuition says), so would this not mean there are lesser and greater pockets of gravity medium density, in proportion to the vertical axis from N to S of the sun in relation to the square of the distance?

That is to say a probe sent from earth, would experience greater gravity aligned with the suns N and S poles, then it would as it moved to be aligned with the suns equator?

Do you get what I am asking here? Do you see this intrigue?

That a sphere is traveling through a seemingly finer grade material medium, and other spheres that are smaller than this sphere is following it, because the large sphere, moves the material medium in such a way, that the material medium is 'strengthened/fortified/tense' so that the smaller spheres are forced by this medium, to be moved towards the larger sphere.

The reason the square distance drop off;

If we are stationary observers acknowledging that a sun will be passing by our view of observation;

We will observe a sphere moving past our view of vision, and we will see observe that the gravity medium is always bulged locally relative to the sphere;

If we define exactly directly in front of our selves as X, and then a little to the left -1, a little more -2, a little more - 3 etc., and exactly to the right of X, 1, 2, 3, etc. In the entire event of this event of sphere passing through our field of vision, at all number points, will all the values of the sphere and gravity field have been at;

There will be a moment when the center of the sphere is at 5, 4, 3, 2, 1, x, -1, -2, -3, -4 and thus there will be the time when each value of the gravity field slope due to the sphere will be at those points too;

Because the sphere moves the medium at point 5, 4, 3, etc. and then the sphere continues to move onward, the medium must be assumed to continue to move at these points it was moved at (put in motion stays in motion);

thus it must be said;

Because mass exists;

Because gravity medium exists;

Because they are attached in some most non trivial and hopefully not for long mysterious way;

Because the mass infinitely moves;

The gravity medium infinitely moves;

Though the strength of the effect of movement, is greatest, where the greatest mass is, and thus drops off