What’s Up with Gravity? part 2

In part 1, I talked about fields and field gradients.  I want to expand on that just a little because I believe that it is key to action-at-a-distance and gravitational forces in particular, and I think I can make it a little clearer.

We know that Einstein’s General Theory of Relativity tells us that gravity is a result of space-time warping in the presence of a mass, often shown in figures as a membrane with a large body (such as the sun) in the middle, sitting in a depression in the membrane and a smaller body (such as the earth) circling around in a smaller depression in the same membrane.  I mentioned that we humans have a tough time getting our mind around that situation when it comes to our own bodies in the earth’s gravitational field.  When we are standing on firm ground, where is the membrane and what is being warped?

I also mentioned that a mass is surrounded by a field and we can draw a circle or sphere around that mass where the field strength (gravity) is the same at all points on the circle or sphere and additional circles around points further out for smaller and smaller strengths.   The result is a series of shells that stretch out to infinity, or at least as far as light has traveled since that mass was placed in that position.  This is different than the normal depiction of fields as being lines connecting two masses along the lines of force.  I’m convinced that my shell drawing of equal strength points will be easier to understand.

The figure above illustrates two situations.  Figure 1a shows two masses that are different sizes and also far apart.   The field lines are drawn around each for some easily measurable strengths and the drawing shows only those fields that have sufficient strength to measure on our crude meter.  In fact the fields go on forever in ever-decreasing strength.  If we had a better meter, we could draw lines all the way between them and beyond.

The fields in figure 1a are essentially circles around each mass because the masses are positioned so far apart that we can’t discern any distortion in the circles.

The fields in figure 1b show a situation where the smaller mass has been placed closer to the larger one and overlap the outer two measurement circles of each.   The figure shows that the fields merge.   The outer rings of both masses were the same strength before and still are because we are measuring the field at equal strength at the minimum reading we can take with our poor meter.  

Notice that the outer ring and the one just inside of it have now combined for the two masses and as a result of the added strength moved out a little further, that is, bulged further out on the far side of the small mass.  In addition, the 3d ring of the bigger mass has also bulged a little due to the movement of the others.   It should be clear that the fields in the bulged areas are not stronger, but are the same strength as before, but now our measurements of that strength are further out.

The two masses are now part of one system  and the rings around them are distorted a little at all points as they now form equal fields around the center of gravity of the two masses.  That is not really apparent in my simplified drawings, but the system now acts as a larger mass to other masses (not shown) further out.

Our body is a system of masses that act like the system above but infinitely more complicated as the fields of every molecule of our body interacts with every other and with fields external.  However, we can now visualize our body as being the smaller mass and the earth a similar system of masses much bigger.   When we are on the earth, our mass interacts with and modifies the earth’s field ever so slightly (and the earth ours), but sufficient to feel the effects due to the enormous mass of the earth.

There is still a gradient across the two masses (the fields on each side of it are different sizes), and a tension across the gradient that tends to pull the masses together.  Actually, it is not clear if it is a pull or a push.  Is the larger mass pulling the smaller one or is the enhanced field that has now moved out behind the smaller one now giving it a slight push?  To be complete we have to say the small one is also pulling on the larger one or possibly the field behind the larger one is pushing it toward the smaller one.  Indeed the field behind the larger one has also moved out ever so slightly in the same manner as shown for the smaller one, but not discernable from the drawing.

From the drawing, I’m inclined to say they are being pushed together, in the same manner that a rubber band wrapped around two fingers pushes the fingers together.    

How did the fields get there in the first place?

There is no question that the fields are there.   But is the gravitational field moving at the speed of light outward from the mass?  The short answer to the last part is no.   The fields as I explain them are essentially static.  They are modulated by disturbances within the core of the mass (quarks, gluons flying around) but the field strength is essentially static except as modified by the fields of other masses elsewhere in the universe.  That modulation of the fields goes on constantly in ways we could never compute.   The modulation or changes in the field do move at the speed of light, but the lines drawn around our figure do not change except as other masses move and influence the fields.

The answer to the title question “How did the fields get there in the first place?” is this:  They have been there since the mass was created.   For the atomic scale, we are talking about when the quarks and gluons first condensed out of the big bang expansion and atoms and other particles were formed.   Each atom and each particle that has mass had a field established at that time and it has followed them around ever since.   On a larger scale, as atoms combined into molecules and dirt and other debris combined into lumps and moons, the systems of fields depicted in figure 1b began to grow as well.    Eventually a sun was formed, an earth was formed and we were born into it.  Our masses accumulate and become a smaller system of our own.

Thus we are composed of atoms from the creation and from the deaths of stars which may have flung our larger atoms and their attendant fields out into space to end up as us with enough intelligence to understand a few things about our world, including a little about gravity.

Where does mass come from?

If gravity is a function of mass, where does mass come from?   Actually there is no problem here:  if E = mc^2  then it can be restated as m = E/C^2.   Simply put, mass is a form of infinitely condensed energy.   Release the energy and you have an atomic bomb.   The components of an atom really have very little individual mass among them.  All of the mass is ultimately from the energy within.   The quarks and gluons and other stuff inside are moving about in a wildly speedy fashion, like a whirling dervish.   In effect, gravity is more of a function of energy than any real matter.  

The point of mentioning this is that I believe that the gravity fields that were established at the beginning, shortly after the big bang, are the left-over effects of energy being condensed into matter – huge amounts of energy being squeezed or formed out of the soup of creation during the bang and leaving lonely fields stretching out forever and following that condensed energy wherever it goes.  So what holds us down is essentially the debris of locked up energy condensed when our atoms were created, long before the earth was formed and eventually accumulated into the ground we walk on. 

Copyright 2007 by James A. Tabb

Marietta, Ga. 

  

What’s Up with Gravity?

Gravity is a problem for physicists.

It not only affects mass, but all forms of energy. If you add energy to a mass, its gravitational effect is increased as well but only minutely because an enormous amount of energy is equivalent to a small amount of mass.

Gravity is weak, far weaker than electrostatic forces. Jump off a building and you go splat when you hit the earth. What took perhaps 20 stories to accelerate you to the splat speed is gravity. But the thousandths of an inch that you were stopped in was due to electrostatic forces. Electrostatic forces are the forces that keep your fingers from going through the keyboard.

Gravity also affects matter at a distance – forever like distances. Every atom in your body contributes to the earth’s attraction of the moon and the sun. Consider a molecule of water in the ocean. It is pulled as part of a tidal force by the sun and moon and it in return pulls on both the sun and the moon. Taken together it all adds up.

Gravity is not shieldable.  Elctrostatic effects are. You can build shields to protect you from most radiation and from electromagnetic fields. But gravity is different. If you could shield from gravity, you could build a big enough room to float around like spacemen. But the gravity force on a pea is just as strong no matter what you put around it.

Einstein developed a theory for gravitation – General Relativity – in which gravity is the effect of a distortion of space and time in the vicinity of mass. We can visualize that in the isolated case of the earth moving around the sun as a depression of a membrane representing space and time around the sun.

However, we can’t get our minds around that being the case when you or I standing on a set of scales. What space and what time are we distorting? How does an individual electron’s mass affect another one a mile away? A million miles away? What is going on?

Lets make a distinction: Gravity and Gravitation. “Gravitation” is the attractive influence that all objects exert on each other, whereas Gravity is the force that objects exert on each other due to their relative masses.  Maybe I can state it more simply: one is an influence (gravitation) and the other is a measurement (gravity). For example, a marine sergeant can influence a recruit to jump by yelling at him/her; how high they jump is a measurement. Gravitation is the attractive influence of you or I on the scales by the earth’s mass in relation to our mass. The scale indicates the weight. The force causing that scale’s hand to move is a measurement of gravity.

Fields

Fields are invisible lines drawn around objects to represent the points of equal strength of some measurable value. For example we can draw field lines around a magnet’s poles – points where the strength of the magnetic pull are equally strong. You have probably seen (or seen pictures of) magnetic filings on paper above a magnet. Those are lines of force that represent the effect of field gradients, not the points of equal strength that I’m making a point about here. The filings line up along gradients of the fields of the magnets, dipole to dipole so they create lines running from one pole to the other. These lines are often called fields. The ones I’m speaking about are equal strength fields that surround each pole. The filings are linked across those equal strength fields and bridge across the gradients, dipole to dipole.

Fields around single (isolated) objects, such as a charge field around an electron or such as a gravitational field around the same electron, are spaced outward like a shell, keeping the shape of the object but expanding as they go, unless interfered with by another field from another object. The difference is that other objects don’t interfere with the gravitational field (unless it is supermassive like a black hole) All points an equal distance from the object have the same intensity or measurable value. Field lines get weaker as you go away from the object due to the measurable effect becoming weaker as you move away This results in a field gradient from one field surface to the next.

A disturbance at the object (say somehow its mass doubles as two atoms merge) changes the fields at the speed of light, like a ripple in a pool of water. In other words, if the moon were somehow removed at a given moment, the earth would still feel the gravitational pull for just over 1 second (1.2 to 1.3 seconds). If the sun were removed at a given instant, we would not know about it (visually or gravitationally) for about 8.3 minutes.

A disturbance of the type where the mass doubles would cause the field shell that represents a given strength to jump to a distance further away from the mass center. The change would occur at the speed of light, so it is dependent on the distance to that field line or surface. It does not change instantaneously as some suppose and it does not change gradually as might otherwise be supposed. Therefore an object at that point would become affected by gravity at the same instant that light would arrive, not before.

The gravitational fields around an object have gradients that decrease with distance, but go on forever. An atom in your arm has a field that reaches the sun and beyond, but very very weakly and completely swamped (for measurement purposes) by all the other fields generated within the earth. Just the same, it does contribute. Everything adds up. Move your arm and the fields change throughout the universe at the speed of light.

Isolated static (electrical) charges affect each other though the gradients of the fields. They want to move toward each other if the charges are different and the fields tend to cancel or else move away from each other if the charges are alike. They move or experience forces across the gradients. Moving charges affect each other in different ways and their movement produces magnetic fields and magnetic fields also induce movement of charges. They are strongly attracted or forced apart if they are close together because any outside influence that would pull or push them are effectively shielded over relatively short distances by their environment.

What about gravity? Gravitational pull is very weak. What causes that weakness? Why don’t objects closer together (such as your fingers on the keyboard with the keyboard) strongly attract each other? Why doesn’t the massive earth crush us in its gravitational field?

My thoughts

These are just my thoughts, part of my personal theory of gravity. Feel free to discount it or shoot it down.

Isolated static gravitational objects also affect each other through gradients of the fields. Atoms, particles with mass, and all forms of energy are always moving. They jiggle. When they vibrate they do so in the gradient of another object’s gravitational field. I’m not talking about the vibration of one atom against another as being any significant part of the gravitational effect, but instead talking about the quarks and other ingredients of the atoms that are always in motion, those most intimate particles that have mass of their own. The gradients they encounter are also jiggling because the remote masses are ultimately composed of the component parts of atoms, and free particles, always moving.

They are affected only minutely by the gravitational field, which has a very small gradient over the volume of the effective mass of the particle, but they are affected nevertheless. The effect is somewhat like the small magnetic particles which form dipoles in magnetic fields and line up across the magnetic gradients, but these are not magnetic but instead gravitational. There is a gravitational tendency to move toward the other object’s mass, toward stronger gradients and away from smaller ones. Masses tend to congregate, group into crowds, pull together, clump up and possibly create cosmic objects, even suns and earths.

It is not that the gravitational field is so small. It is the competition of the gravitational field of our localized individual component masses within the earth’s gravitational field gradients embedded within the background of all the fields of all the masses of the universe also affecting us.

This competition is not present for electrostatic and electromagnetic fields, so they appear stronger – much stronger.

Our jiggling particles have masses that operate within a gradient that is quite small compared to the size of those masses. All the masses in the universe are contributing to the fields experienced by the particles in our body and the result is a small but measurable attraction that is normal (perpendicular) to the gravitational fields of the individual particles with a tendency to be pulled (a force) toward the center of those fields, force and/or movement toward the stronger gradient of the field. But the overall effect is small even though the earth is huge in relation to us.

When an object absorbs energy, its mass goes up because its jiggling goes up and it has a measurably (but very small) higher gravitational effect as it interacts with the field gradients. Cooling a mass to near absolute zero reduces the energy within the mass, those parts that bang against each other, but does not stop the motion of the quarks and other ingredients that make up the rest mass of the object’s atoms. So the gravitational attraction for that object does not diminish appreciably as it cools.

Bring objects closer together, and the gradients get higher at a quickening rate and the attraction gets higher and that effect swamps any energy effect due to cooling or heating. Just the same, the gradients from the masses of the rest of the universe are there all the time and tend to keep the gravitational force small compared to other forces generated by other fields which have limited effect. The gravitational effect can be quite large, but the gravitational force quite small. Gravitational fields around particularly large objects such as black holes and even our sun do get warped because space and time are also warped in those vicinities.

Space-Time Warping

What I leave unanswered with this paper so far is what gravity actually is. What I’ve described above is why I think that a field gradient makes things tend to have gravitational attraction and develop a force between them that we call gravity. I didn’t say anything about what makes the fields themselves. You can go to a certain point around an object and trace out a measurable effect and call it a field but you can’t say what caused the measurable effect without resorting to Newton or Einstein or perhaps gravitons.

In my opinion I have no quarrel with Einstein’s general relativity and its gravitational predictions or his development of the theory of gravity. It is a beautiful work. The mathematics are wonderful to behold and I don’t pretend to know anything about them other than they work and continue to stand up to careful study and experiments, and they also answer the question as to what makes the fields possible, why you can measure an effect at any distance from an object with mass.

It is a matter of relativity!  

 It is space-time warping, the same as with photons. Gravitation seems to be part of the same effects that I’ve been describing for quantum weirdness, and the fact that fields expand or adjust themselves at the speed of light helps make that case.

Fields as I’ve described them don’t move at the speed of light, they are static for static objects. Changes in the field at the source do adjust the fields at the speed of light. However, you can make a case for the changes to be constantly and forever moving the ripples because the masses within every atom (quarks, etc) are always moving and we and all our masses are forever moving on this earth and through the universe. In other words, the changes in the fields, though minute, are always moving at c and always present.

It may be these changes moving at the speed of light that is always running on zero-time zero-distance that are the foundation of action at a distance and gravitation in particular. Every particle in every atom is moving and so there are always field changes moving away at the speed of light, always attached to both the particle and the masses it encounters elsewhere in space and always applying a minute force on any mass it encounters wherever in the universe that might be.

Gravitons

I personally do not adhere to the idea that gravitons exist. Gravitons are a hypothetical theoretical particle that mediates the force of gravity within gravitational field theory. Such a particle would move at the speed of light and have a spin of 2. It would also be massless as a necessity of its speed. It has a lot of problems including “blowing up” (becoming infinite) in situations involving more than a couple of them at any time at energies in the ultraviolet range. The equations in the latter case cannot be renormalized. String theory helps the graviton, but it too has enormous problems.

If there is such a thing as a graviton, it is actually an effect of the changes in the ripples of the field that is caused by the motion of the components of the atoms or free flight particles. As such it could be conceivably be quantized and thus the ripples in the fields might be quantized. So maybe there is such a thing after all, but I’m not sure you can call it a particle and I’m not convinced it has to be a quantum object. The ripples I’m talking about moving from one mass to another are changes in the field that expands as it grows, and diminishes in strength as it goes flying out into space in all direction at once like a shell of a balloon expanding at c. That would be stretching the definition of a graviton quite a bit.

I think my way of looking at it is much simpler and has the effect of making sense to my feeble brain. I’ll leave it to Newton’s equations for most purposes and Einstein’s for special cases for the calculations. They work well. I’m sorry, but gravitons don’t excite me.

Copyright 2007 by James A. Tabb

Marietta, Ga.

aka  Oldtimer