Pressure
Alter-self: What is Pressure?
Self: Why, It is the interaction of matter changing states.
But, an interaction isn't an entity is it?
No, but to be a reality does not require something to be an entity.
Energy is not an entity, why did you say it is not real?
Energy is an after the fact measurement of how much ability or capacity of work was done; and work is actions of nature as they are happening. Work is the name for real actions of nature.
Why didn't you put "work" in this section on reality?
Because work can be broken down to a more elementary level that is just motions of entities and pressure interactions. And, these actions, can be measured, sensed, and observed.
Hum...
Alter-self: I can sort of understand how it might have been in a beginning of the Universe, where there could have been a whole bunch of tiny particles turned loose... And, if these particles were in motion, they would fly about Space and force themselves upon one another with impulse pressure contacts... but, how did that change the particles into electrons, protons, and stuff like that; and would cause them to work, and gang up together, like elemental type groups... and to finally go on to form a Universe? Was Light some of this same beginning stuff that got exiled and turned itself into something a bit different that the main group? What about life? What makes you and me think like this?
Self: Stop, Stop... Stop! There are many things that are still unknown. And, I will continue to wonder about these items. But, I am not going into a depth that, for my knowledge, I haven't a clue! I will just stay with my hopefully reasonable beliefs and deductions, that Pressure is the action for all forces and it is real.
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And, if I apply the other test for something real... the Universe cannot do without pressure forces; it would not be the same.
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All bodies of matter in the Universe consist of particles. Theory has it now that the very smallest elementary particle of matter is a quark. Moving upwards in size we come to electrons, protons, and etc. Then we have atoms that can group together to get molecules. These particles have motion. These atoms give off photons of light at times, and take on photons at other times. Atoms have increased and decreased amounts of activity. This is why an iron bar that is hot expands. Matter will bend, and or break... I write all this to remind you that matter is not a solid chunk of material. If it were, the Universe would not function. Matter is elastic, and flexible to varying degrees. For solid matter... it can be flexed and come back, resilient, to its own shape. If it is flexed too far. it will deform and stay, or break.
When two equal billiard balls in motion collide head on, the colliding balls start applying pressure to each upon contact. Atoms and or molecules, at the collision point start moving backward away from the pressure impact in both balls. The atoms in the balance of the balls are still moving forward. In this case we will assume the balls are coming at each other directly straight on and at equal speeds. With all things equal there are equal pressures between the balls, resulting in a null. These opposing pressures are high at the instant of impact and reduces equally to zero as forward motions come to a halt... and then resumes again increasing to the value of the initial impact in reverse, due to resilient recoil. There is a differential of pressure within each ball, as the impact region of atoms trying to squeeze backwards at an increasing rate, and atoms in the rear of the balls still moving forward, but are slowing as squeezing increases. The balls are both compressed to some degree, and this squeezing of atoms causes more atomic activity. They are locked into a solid molecular configurations with minimal motion, but sub atomically are more active. Finally all the atoms in both balls generally stop moving in the direction of the collision, and the balls quit moving forward, but there remains still a differential of pressure across each ball since each is in a compressed state. The atom molecules are in some irregular configuration of stress that is trying to pressure the balls back into their original spherical shape. This is the recoil of the balls, and as they regain their shape the balls push off from each other in opposing directions with equal speeds. When the compressing and recoiling was going on there was always internal differentials of pressure. Also, when the compressing and recoiling was going on there was, first minus acceleration (deceleration), and second, accelerations of the balls in the reverse directions. While all this is happening there was acceleration of particles as changing their states, within both balls. Once all differential of pressure disappears... all acceleration disappears... (With the exception that in the, extreme physics reality of our Universe, everything is in curved motion, and has some amount of pressure forces always acting upon bodies of matter... thus always in some amount of overall acceleration.)
The two equal balls above, hitting equally head on, came away from each other with the same amount of ability to do work as they had before the collision. This ability to do work was due to their additional opposite directional mass, equating to kinetic energy. What they did was, in a sense, both worked on each other equally which resulted in the same abilities to do work, energy, but in different directions. Each had a loss of their forward directional mass and gained a new directional mass in the reverse direction.
When there are two equal billiard balls equally colliding at angles__ The atomic activity actions within the balls are similar, as above. There is also compressions of both balls. The differential of pressures, and accelerations are there. There are new directions that the balls will take upon recoil as above. When colliding at angles, it just gets into the geometry of angles, directions, velocities and such for the external motions.
If the scenario is two equal billiard balls, that hit each other at at unequal speeds, or as one moving and one idle... It becomes a situation where the balls compress, and recoil enough to match the slowdown to a stop of the moving ball... which means this ball is losing it directional mass with loss of forward motion. The idle ball is compressed and recoils to go into motion and gain directional mass in an amount equal to the directional mass the first ball had. In a sense, it is setting itself into motion... by recoiling from its compression, but some work had to be done either from impact collision or squeezing and releasing initially, to create the squeezed state.
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The aforesaid billiard balls had differential pressures that had acceleration to go hand in hand. Can we have bodies in a condition of pressure without acceleration, or work being done, or having directional mass? Or as pressure without being a differential. Yes.
Whenever there is a zero null between two bodies pressing against each other, the point of contact will not be a differential. (There may be a differential behind the contact points)
If I were to clamp a block of brass in a screw vise__ while I was increasing the pressure of the vise jaws to the brass block it would be much like the two equal balls coming together. There is compression of both the vise jaws and the brass block. (The work is originating from me to the screw, to the vise, and to the jaws... ) At some point I stop squeezing the brass block. It is held there under pressure... It is much slower than colliding, but while I was squeezing the block, there was compression of both the block and the jaws. And, as the pressure increased there was change of state within both block and jaws. In the scenarios with collisions at the end of the impact the pressure is released and allows for spring back or recoil... but. with the vise I am keeping pressure maintained upon the block. Is the vise still doing work holding the block? Maybe for a short moment or two, but after that... No... Within the jaws of the vise, and within the brass block, after the acceleration due the motion of tightening... there will still be atomic thermal activity. Whenever there is compression, or pressure applied there is an increase in atomic activity... there is also an increase in temperature in the bodies under pressure. Once the pressure quits increasing no additional agitation is occurring so the temperature goes down as the heat is radiated from the bodies. When the heat is back to normal, the bodies are held under pressure, and are in a condition of stress, but are not doing work. The vise and the block are at their at rest mass. If the squeezing did not cause over-stressing__ when the pressure is released there will be resilient spring back to normal with acceleration, and a differential of pressure while this is happening. If something is over-stressed it will break, or stay bent; over stressing will completely break atomic molecular bonds, or change them to another configuration... which results in breaking or permanent distortion to a new shape.
I know some people will ask how come, it is work for a person to squeeze, and hold a box tight? Yep! You're correct, it is work, and a person can even work up a sweat... Our bodies are flexible and fluid. They are not like solid metal; that has a built in molecular structure that holds it shape stiffly. If you lie down on the floor with a book on your stomach, there is pressure from the book... but you are not working hard to hold it there. If you sit on the book there is pressure from you to the book, but with little effort. But, if you hold the book out at arms length... it will become work. Due to gravitation, the weight of the book, and your arm's weight, will put stress on your muscles, and your body will work to keep blood pressured into the proper muscles to keep your arm in an outstretched position. It is also difficult to put much pressure on water or air, unless there is containment of some type. It is a 24/7 working job of your body just to stay alive.
I will tell you here... I do not know exactly how the atoms and molecules hold themselves in their various configurations, and go into a condition of stress when deformed. To hazard a guess I would suspect that it would be as magnet unlike poles being held apart, or like poles held close together. I don't think anyone else knows the answer either. But, I'll bet there is pressure involved!
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I know, just because there are millions of assorted entities in our Universe that exert pressure, does not prove that all forces are of pressure. But, there are a couple of other formidable items that help the assertion that pressure is all forces...
Attraction is an action at a distance, and never been explained how, and would appear to have a greater amount of difficulty than pressure. However attraction might be viable if explained with pressure...
Particle exchanges may be true, but for a particle to be emitter, or radiated... it probable has pressure to set it in motion... there is probably more to his story...
Pressure is not only of classical physical stuff, but is of light, and atomic particles, and is in quantum mechanics.
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Page Relevant Quotes
"We all know that electromagnetic waves transport energy. Perhaps you also know that such waves can transport linear momentum. That is, it is possible to exert pressure (a radiation pressure) on an object by shining a light on it." Fundamental of Physics: David Halliday, Robert Resnick, Jearl Walker."
"Newton concluded that the acceleration given to a body by any particular force will be independent of the form, dimensions, and constitution of the body; it will depend entirely upon the amount of matter that the body contains__ in other words, it's mass. The fundamental law of dynamics is:
F = mγ
where m is the mass of the moving body, F the force acting on it, and γ the acceleration produced. This law shows quite clearly that the only property of the body which is relevant to the study of motion is the mass." Quanta: J. Andrade e Silva, G. Lochak
"Lord Rayliegh pointed out that, in an ideal fluid, a ships propeller would not work, but on the other hand, a ship (once set in motion) would not need a propeller." Fundamentals of Physics: David Halliday, Robert Resnick, Jearl Walker.
"Heisenberg uncertainty principle; principle of indeterminism: The principle that it is not possible to know with unlimited accuracy both the position and momentum of a particle. An explanation of the uncertainty is that in order to locate a particle exactly, an observer must be able to bounce off it a photon of radiation; this act of location itself alters the position of the particle in an unpredictable way. To locate the position accurately, photons of short wavelength would have to be used. The high momenta of such photons would cause a large effect on the position. On the other hand, using photons of lower momenta would have less effect on the particle's position, but would be less accurate because of the long wavelength." A Concise Dictionary of Physics: Oxford
" ...illustrated by considering the movement of a tennis ball.
Classical mechanics tells us that the movement of the ball can be represented by two parameters - the position and the velocity of the ball at any instant - and that a simple means of measurement would be to film the ball so as to note its position at equal intervals of time. Next, we must ask ourselves whether the movement of the ball is independent of our observation.
The answer is, emphatically, 'no'. We cannot film the ball in the darkness, but as soon as we illuminate it, the light exerts a pressure on its surface, and the velocity and motion of the ball will be disturbed. Admittedly, in this case the effect is negligible, but the principle is clear enough. we cannot measure the behavior of the ball without modifying it; in other words, to measure is to disturb." Quanta: J. Andrade e Silva & G. Lochak
"From the point of view of the atomic theory, we can at once say that heat energy is nothing but the energy of motion (to which must be added in some cases the potential energy) of the molecules of which matter is composed. Let us consider a gas, for instance. It consists of molecules, more complex in some gases, less in others, but in all cases about a hundred-millionth of an inch across, with comparatively large spaces between, moving about in all directions with an average speed measured in hundreds of yards a second. The molecules collide with one another, and lose or gain in speed at collision, so that all velocities from very small to very great are represented. ...The hotter the gas the more lively is the motion of its molecules, or, more precisely put, the greater the average energy of the molecules. ...If the vessel be closed the more lively beating of the gas molecules against its sides produce the rise in pressure which we know takes place when a gas is heated in a sealed space.
In a liquid we likewise have energy of motion of the molecule... In a solid the molecules are anchored to definite spots... and vibrate about that spot like balls held by springs. In all cases, however, the heat energy is simply the energy involved in different modes of motion of the molecules." An Approach to Modern Physics; E. N. da C. Andrade
"Galileo taught that 'Nature abhors a vacuum... It is to be noted that the action of a pump is not properly described as 'suction'; that is, in all such cases the motion that results is due to a push from behind rather than a pull in front." A Survey of Physics for College Students; Frederick A. Saunders.
"The term pressure (p) we must confine rigidly to one definite meaning, namely the amount of force (F) per unit area." A Survey of Physics for College Students; Frederick A. Saunders.