Universal Physics Journal


     Acceleration represents the change in motion of an object or portions thereof.

    If the speed or direction (velocity) of an object's motion is changing relative to a non-accelerating frame of reference, then the object is experiencing acceleration.  Also, as long as an object is rotating about its own central axis, each of its portions is experiencing acceleration directed inward  toward, and perpendicular to, the central axis of rotation. Finally, if the rate of rotation of an object is changing, then each of the object's portions of matter is also experiencing acceleration that is directed along a line that is repeatedly drawn tangent to and on the same plane as the circular path of each portion's rotation about the object's axis.

     There are no occult or non-force causes for an object's acceleration.  Specifically, each and every event involving the acceleration of matter is exclusively caused by the presence of an acceleration/Action force.  The acceleration/Action force may be an internal action force generated within each component of the object's matter such as gravitation or magnetism, or the acceleration/Action force may be an external (contact) action force impressed against the object's surface by another object(s), or some combination of both internal and external a/A forces.  

     (See Article IV: The Nature of Force; Article VIII: Universal Gravitation; Article IX: Galileo's Law of Constant Acceleration; Article X: Universal Physics Laws for Force and Motion: and Question 7: regarding gravitation in space.)


acceleration/Action force   (abr. a/A force)

            An acceleration/Action force is the action force responsible for causing the activity of acceleration for an object.
    The acceleration/Action force may be an internal-to-matter force being generated separately within each component of the object's matter, or it may be an external-to-matter force impressed against the object's surface at one or more mutual points of contact between the object and a second object.  Regardless of whether the a/A force is an internal force or an external force or some combination of both, it always causes the reactive generation of an equal and opposite supporting acceleration/Reaction force within each component of the accelerating object's matter.  Since this supporting a/R force is always an internal force,  the absence or degree of presence of the stacking-of-forces effect within the accelerating object's matter is a proportional indication of whether acceleration/Action force present is totally an internal force or totally an external force or some combination of both internal and external forces.
    Imagine an object in space that is freely accelerating while traveling directly toward Earth (not in orbit of Earth).  Its a/A force will be in the form of the myriad of internal gravitational action forces being generated within each of the object's myriad of components of matter with these a/A forces generally directed toward Earth's center of matter.  With friction absent, and ignoring all other gravitational action forces, a calculation of  mass * acceleration = Force will reveal that 100% of the Earth  gravitational action forces generated within the object's matter are being applied to causing acceleration for the object in Earth's general direction.  Thus 100% of these forces are acceleration/Action forces.  As always, regardless of cause, these acceleration/Action forces generate their own supporting acceleration/Reaction forces.  These a/R forces are always internal forces.  Thus in this event, the result is that there exists no stacking-of-forces through the object's matter in Earth's direction.  This happens whenever one internal force is fully opposed or supported by another internal force within the same component of matter.  No force is left over to seek external opposition or support against neighboring components with the result that no stacking of such external forces is present.  Instead, the internal forces present, both a/A and a/R, are Type 1 forces since they are each finding complete termination against the other within the confines of their single component of origin.  Thus the reason for the object's weightlessness is explained by understanding the cause of its internal equilibrium (See Article IV: The Nature of Force) 
    The object has a small attached rocket which is now set to firing its particle exhaust in the direction opposite to Earth's direction.  One Type 3 bipole external acceleration/Action stacking force of the rocket motor is accelerating the exhaust components in the rearward direction while a bipole partner Type 3 external stacking force is accelerating the rocket motor body and the object ahead in the forward direction toward Earth.  The same internal gravitationally-caused Type 1 a/A and Type 1 a/R forces in the previous event are still present.  Only now upward-directed Type 2 acceleration/Reaction forces are also present.  These internally generated forces reactively bear as upward-directed exterior forces outside their components that stack up from component to component in the direction of the mutual contact point the object shares with the rocket motor.  Now the object is no longer weightless for it has a certain measurable magnitude of Type 2 internal acceleration/Reaction force of weight that it is freely bearing in the upward direction (relative to Earth) against the downward-directed acceleration/Action force from the rocket.
    Understand that both the Type 1 and Type 2 a/R forces present provide the required reactionary support force for the ongoing downward-directed activity of acceleration caused by the downward-directed Type 1 (Earth gravitation) and Type 3 (rocket thrust) a/A forces present.  One must never expect the a/R forces to be capable of canceling or reducing or resisting the accelerational effect of the a/A forces present.  To expect so would be the same as to expect the a/R forces to be capable of canceling their own cause.  The object's reactive a/R forces are merely along for the ride as they always remain directed opposite to the direction of the ongoing activity of acceleration.              

acceleration/Reaction force   (abr. a/R force)

    An object's acceleration/Reaction force is the reaction force the object presents in support for any acceleration/Action force that is the cause of acceleration for the object.  In total, the object's a/R force is always equal in magnitude and opposite in direction to the acceleration/Action force.  The a/R force is always an internal force that is generated within each component of the object's matter in reaction to an imbalance in each component's operation due to that component's acceleration.  Each component's acceleration may be caused by an external (contact) acceleration/Action force initially impressed on the component's object by a second object. 
    As in every case where an external force is opposed to or finds support against an internal force, the first object's internal a/R forces will stack up (increase in push or pull) from component to component in the general direction of the mutual point(s) of contact between the two objects.  The first object's a/R forces, being reactively generated within each of the object's components are directed precisely opposite to the direction of each component's acceleration.  The direction of acceleration may or may not lie along a straight line drawn between the individual component and the mutual point of contact between the two objects.  When considerable misalignment occurs, a forceful challenge to the structural integrity of the object being accelerated by an external force will result. For a good example of  the structural distortion this overall misalignment can cause, consider the event where an astronaut in orbit of Earth takes a weightless rectangular block of gelatin and accelerates it by pushing against the middle of one of the block's sides with the tip of a finger.       
    Each component's acceleration may also be caused by an internal force, such as gravitation, in which case these two internal forces, gravitation and acceleration/Reaction, will interface against each other within each component of the object's matter leaving the object, if not too large, in the weightless state of internal equilibrium.  This weightless state of internal equilibrium will remain the same state for the object regardless of whether the object's acceleration is increasing or decreasing or present at a low rate or at an extremely high rate.  These variations make no difference as far as the object is concerned.  When in the weightless state of internal equilibrium, it is not possible to "sense" one's acceleration.  It is for this reason that astronauts on their way to the Moon have to be told by Mission Control when their space module ceases slowing down (negative acceleration) while departing Earth and instead begins speeding up (positive acceleration) while approaching the Moon.  As weightless "objects" the state of the astronaut's internal equilibrium, between the internal Earth gravitational action forces, the internal Moon gravitational action forces, the internal Sun gravitational action forces, the remaining internal planetary and galactic gravitational action forces and the internal acceleration/Reaction forces present within the astronaut's bodies, remains but one state, regardless of the direction or degree of acceleration present.
     As always, when an internal acceleration/Action force, such as gravitation or magnetism, is the cause of acceleration for the components of an object, since this internal a/A force is reactively causing its own support force in the form of each component's internal acceleration/Reaction force, the stacking-of-forces effect is absent for the non-rotating object.  It is for this reason that all objects initially experience a freedom from the compressive effect of stacking forces upon losing their support above Earth's surface.   If you are the object standing on a trap door in the floor, then before the door's release you will experience the stacking-of-forces effect as your component's internal gravitational non-acceleration/Action forces are mutually opposed by the opposing external forces from the door.  Then after the door's release you will experience the contradiction of a sudden freedom from stacking forces while nevertheless accelerating toward Earth at a considerable rate.  Here your components' internal a/A forces of gravitation are causing their own support forces in the form of each component's internal acceleration/Reaction force.  Your senses correctly predict that your body's components are experiencing internal equilibrium.  What you will have a hard time predicting without additional input is your sudden and considerable rate of acceleration.
     (See Article I: The Reality of Newton's Inertia; Article IV: The Nature of Force; Article V: The Mutual Force Rule)

centrifugal force

Centrifugal force is the internal, outward-directed, reaction-to-centripetal-acceleration force that is reactively generated within each accelerating component of an object's matter with this acceleration/Reaction force always being caused by, and always providing the required support for, the internal or external, inward-directed, centripetal, acceleration/Action force that is responsible for acting as the cause for each component's centripetal or inward-directed acceleration away from a straight path of travel repeatedly drawn tangent to, and on the same plane as,  the component's curved path of travel.


     As a reaction force, the centrifugal a/R force is not responsible for its own cause.  That role lies exclusively with the event's centripetal a/A force.  Hence it is not logical to expect the reactive centrifugal a/R force to be capable of acting as the cause of any outward-directed event.  Instead it always reacts in a benign manner in the outward direction which is opposite to the inward-directed cause by the event's centripetal acceleration/Action force.  In the same manner while riding in an accelerating vehicle one does not expect a body's rearward acceleration/Reaction forces to be capable of "causing" any rearward-directed event while the vehicle is forcefully accelerating the body in the forward direction.  As in all accelerational events, the a/R forces present merely fill a supporting role as they provide the required equal and opposite support for the event's a/A force cause.


     Accordingly, there exists no possibility for the existence of "centrifugal acceleration" for no outward-directed action force exists to cause such an impossible event.  On a final note, any science author who makes the statement: "Centrifugal force is fictitious." simply doesn't understand the physics of accelerational events.  One would be well advised to cast a broad net of doubt upon all the author's statements that follow. 

     (See Article XI: Reaction Forces: Question 3: Question 4: Question 5)


Force is a push or a pull that is either impressed externally against, or generated internally within, one or more components of an objectís matter. 

Force is the exclusive cause of every accelerational event.  No form of energy can cause the activity of acceleration of matter without first begin converted by one technique or another into an acceleration/Action force.  The sudden application of an acceleration/Action force is always the cause of the immediate acceleration of an object according to the dictates of Isaac Newton's formula, Force = mass * acceleration.  There exists no fabled "resistance" to the acceleration/Action force from the object's matter.  In truth, the object's acceleration/Reaction force, the only reaction force to exist in nature, automatically provides equal and opposite support for the object's acceleration/Action force, which action force represents its cause, while serving in no manner to resist, reduce or cancel the ongoing activity of the object's acceleration.


    There are four types for force.  Type 1 and Type 2 are monopole internal forces that act or react in one direction within each component of an object's matter.  Type 3 and Type 4 forces are bipole external forces that act and react in opposite directions as mutual contact forces between objects.  In Article IV:  The Nature of Force, consideration is given to the origination and termination of force as well as how the stacking of forces effect occurs in every event where internal and external forces are opposed.    


    Gravitation is the internal force generated separately within each component of an object's matter due to an imbalance in the component's operation caused by its reception of small portions of expanding energy fronts previously emitted at the speed of light energy by and from other components of matter located both near and far.


    The forces of gravitation, being generated within the myriad of an object's components may collectively stack up or combine in a linear fashion to produce the external force of the object's weight against Earth.  Or, each component of the object's matter may interface directly with an opposing internal force such as the acceleration/Reaction force resulting in no stacking-of-forces through the object in any particular direction.  Instead the object will enjoy the balanced state of internal equilibrium during acceleration within a friction-free environment.  Just such an example is the Space Shuttle while in orbit of Earth.  Here the outward-directed internal a/R forces that react in support of the Shuttle's inward acceleration away from an imaginary tangential straight-line path are a perfect match for the inward-directed internal gravitational action forces that are the cause of the Shuttle's inward-directed acceleration.  If the forward speed of the Shuttle is increased, the inward force of Earth gravitation being generated within each component of the Shuttle's matter will become insufficient to maintain the Shuttle's current orbital radius.  Instead, a brief increase in forward speed for the Shuttle will automatically result in a temporary increase in the Shuttle's orbital radius.


    (It should be noted here that the imaginary concept of "curved space" around Earth is an unsuitable explanation for the Shuttle's orbit.  This concept holds that gravitation is not a force and further that the orbiting Space Shuttle is really traveling in a straight, non-accelerative manner along a "curved path" through "curved space".  If this were so, then there would be no speed requirement for the Shuttle's orbit of Earth.  An increase or decrease in the Shuttle's speed along this "straight-path through the supposed "curved space" around Earth would not cause any change to occur to the Shuttle's orbital radius, which we know is definitely not the case.  Thus, this "curve space" theory of gravitation is a theory without merit.  See the definitions for space and time plus read Question 13.)           


   "Inertia" is not anything real in nature and therefore has no purpose or role in physics.  To finally set "inertia" aside is no loss.  Its thoroughly confused definition and description by Newton in PRINCIPIA camouflaged his recognition of our modern-day acceleration/Reaction force as you will note in the following quote from DEFINITION III.  "But a body only exerts this force when another force impressed upon it, endeavors to change its condition..."  Here Newton's "inertia force" is Universal Physics's acceleration/Reaction force being caused to exist by Newton's "another force" which is today's acceleration/Action force.  With Newton's "inertia force" finally gone, we are now free to describe forceful events in a manner that makes sense while remaining in full agreement with Newton's LAW III.
(See Article I: "The Reality of Newton's Inertia".  Also see the definition of the acceleration/Reaction force.)


  "Infinity", a term often used in the mathematics of physics, means simply "without end or limit".   While the predictions of calculations may lead one to consider that it is possible for something to become "infinite", logic tells us otherwise.  To begin with, recognize that it is not possible to count one's way to "infinity".  Equally impossible is the application of any mathematical operation to a supposedly "infinite" quantity.  Divide an "infinite" quantity in half and what do you have?  Will each half not continue to be "infinite"?  Of course, a division of any true quantity in half will yield two ends at the point of division and since an "infinite" quantity is without end, then for this reason alone, it must not be possible to divide an "infinite" quantity.  Also the term "infinite quantity" implies the presence of something to which units of measure apply.  What then if you subtract one of these units of measure from the "infinite" quantity?  Are you left with a quantity that is "infinite" - 1?  Will such a reduced "infinite" quantity of something no longer be "infinite"?  If so then by adding back the quantity removed will the something's "infinite" nature be restored?  If not, then maybe the "infinite" something remains "infinite" no matter how large the quantity removed.  Perhaps even the quantity removed, however small, is itself "infinite".  These consideration predict that an "infinite" something not only cannot be divided but also cannot contain measurable units of quantity.     
    Thus it becomes logical to conclude that if something can be divided into measurable units then it is not possible for this something to ever be large enough to be "infinite".  Thus we are left with only nothing to be "infinite" since only nothing will refuse to succumb to being divided into measurable units.  Conclusion?  "Infinity" = nothing.  Since only nothing can be infinite, then mathematical operations that go so far as to predict that given the right conditions, something that contains measurable units can become "infinite", are mathematical operations that cross the line separating the logical from the illogical, the possible from the impossible, and the real from the unreal.  To follow such predictions and  those who make them is to become lost from the age-old quest to understand the physical reality of this Universe.

internal equilibrium

Internal equilibrium is the state when the internal forces being generated within an object are in balance.  This balance of internal forces leaves the object in the weightless state of internal equilibrium, regardless of whether the object is in the non-accelerating state of rest-motion or is  experiencing the state of acceleration caused by an internal acceleration/Action force of any magnitude.  An object that begins to accelerate toward Earth upon losing its support, will, at least initially, be in the state of internal equilibrium as its myriad of components generate internal gravitational acceleration/Action forces which, in turn, act as the cause of their own equal and oppositely-directed internal supporting acceleration/Reaction forces.  Should the falling object be accelerating through generally still air then the object's state of internal equilibrium will soon end as its rate of acceleration diminishes to zero due to the increasing external support from friction with the surrounding air.  Should the falling object be accelerating in a pure vacuum then the object's state of internal equilibrium will continue until such time as the object impacts (negatively accelerates) against Earth.
    (See Article IV: The Nature of Force)  


Mass is the quantity attribute for an object's matter.  An object's matter has many other attributes including length, width, height, volume, density, weight, temperature, etc.  Mass is the answer to the question: "How much matter does an object contain?"  This answer may be expressed in pound.mass (abr. lb.m) or grams with the former being the quantity of matter required to generate a gravitational weight of 1 pound.force (abr. lb.f) when the matter is weighed in a vacuum at sea level at both of Earth's poles at the time of year when the Sun appears to be on Earth's horizon, with the result being the average of the two weighings.

   As the quantity attribute of matter, mass has no attributes of its own for it is nothing more real than a number.  Thus an object's mass attribute does not have length or density or weight just as an object's length attribute does not have mass or density or weight.  Whenever a mass attribute is referenced, the object, whose quantity of matter is being stated, must also be identified.  It is correct to say:  "The mass of the paver measures 1 lb.m or 453.6 grams."  It is not correct to say: "The mass has an Earth weight of 1 lb.force."  Here no object is specified and further, the mass attribute of this unspecified object can not have a weight attribute of its own.
(See Article VI: Gravitation = Acceleration?; Article VIII: Universal Gravitation; Question 4: A.C.E orbital forces; and Question 11: Why objects fall at the same rate.)   


Matter is the substance of which an object is composed.  Matter is real with many attributes such as length, width, height, volume, density, mass, weight, temperature, etc. 


    Rest-motion is an object's default state of motion where acceleration is absent.  A non-accelerating observer will see an object in rest-motion as either being at rest or moving with a uniform motion in a straight line depending upon the rest-motion of the observer.  The opposite to the inactive default causeless state of rest-motion is the active, forcefully caused state of acceleration.


    (See Article II: The Equality of Rest and Uniform Motion; Article IX: Galileo's Law of Constant Acceleration; and  Article X: Universal Physics Rules for Force and Motion.)


    Space is the room available for matter to occupy and into which energy emission rings may expand. Any discussion regarding space should begin with a discussion regarding the concept of nothing. Nothing is the absence of something. Since a thing is an object of matter, however small, then nothing or no-thing is the absence of something or some-thing which means that where nothing is concerned, all objects of matter and their components are absent.  This state represents the best way to begin thinking about space.  Space, by itself, is nothing but empty room.


    (See Question 7: Curved Space?)


state of motion

    An object's state of motion represents its level of accelerational activity.  There are but two states of motion possible for an object.  The first state is rest-motion which is the default state of motion where all acceleration is absent for the object or portions thereof. 

    The second state of motion is acceleration where changes are occurring to the speed, direction, and/or rate of rotation of the object or portions thereof.  Whenever acceleration is occurring to the object, it is being caused by a net acceleration/Action force of one type or another.  This net a/A force causes and is equally supported by the object's mutual acceleration/Reaction force.  When no net acceleration/Action force is present, the object just inactively waits in causeless default state of rest-motion for the arrival of the next net acceleration/Action force.  Nothing is required to be present to "cause" the object to wait.  It simply waits in rest-motion due solely to the absence of a net acceleration/Action force.

    (See Article IV: The Nature of Force; and Article XI: Reaction Forces)            


(February 15, 2001)
    The definition for time is coming soon, after a reasonably short period of elapsed time. Curious, is it not, that we understand exactly what it means to have to wait for the passage of a set period of elapsed time... yet we claim to be quite puzzled by the nature of time, itself.  The true definition of time is not the complex, conflicting, multi-headed definition currently accepted within the sciences.  Instead the definition of time is but one definition that is simple, clear, absolute, real, and "timeless".  The hard part will be in our getting used to this true definition for it really sets the parking brake on the activity of our imaginations.

(May 5, 2001)
    We all exist in the same Universal Present.  The Universal Present is in constant motion from one present moment to the next present moment.  This motion is time. 

Time is the motion of the Universal Present.


    Think of the Universal Present as the time container for every object, event and emission that exists in this Universe.  To continue to exist in the Universal Present, it is a requirement that every such object, event or emission proceed toward the future at a rate identical to the Universal Rate.  Continued existence in the Universal Present of any object, event or emission is proof that the Universal Rate of Time is being maintained by all in existence.


(See Article VII: The Nature of Time)     


Weight is the external force that one object freely bears against a second object.  
    An external force is a contact force that one object transfers to a second object across the point(s) where the surfaces of the two objects are in contact with each other.  Freely means the one object is acting of its own accord, without assistance from an additional external force being provided by a third object.
    Thus an object may freely impress the constant external downward force of its gravitational weight at one location against Earth's surface or, the same object may freely impress the varying external rearward force of its acceleration/Reaction force of weight against a cross-hull bulkhead of a rocket ship that is accelerating forward at various rates due to varying magnitudes of thrust from its rocket motors while operating in deep space.
    Besides gravitation weight and a/R weight, an object may also exhibit a magnetical weight, an electrostatic weight, and so on, based upon the type of internal force being generated within each of the object's components of matter.  These miniscule internal forces stack up from component to component through the object's matter in the direction of the point(s) of shared contact with the second object across which the first object freely bears with the external force of its weight.   
(See Article IV: The Nature of Force; Article VI: Gravitation = Acceleration?; and Article XI: Reaction Forces)   

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