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Mass and Energy

mass-and-energy

What ARE They?

Mass is said to be equivalent to energy by relativists. Let’s see if we can figure out what they mean.

Mass is the quantity of inertia possessed by an object or the proportion between force and acceleration referred to in Newton's Second Law of Motion. - Physics.About

Either possessed by an object or a proportion between concepts? Well, that was what someone had to say about what he thinks Newton had to say about mass. Maybe we should ask the father of Relativity.

“It is not good to introduce the concept of the mass M = m/(1-v2/c2)1/2 of a body for which no clear definition can be given. It is better to introduce no other mass than ‘the rest mass’ m.” - Einstein in a letter to L. Barnett in 1948

Einstein tells us it is one thing to use this first definition of mass (as being inertia) in F=M/A, but not in E=MC^2.

Whatever does he mean? Clearly he understood it as a concept. Maybe if we define all the Key Terms in the definitions we can reach some kind of understanding of these enigmatic words: mass and energy.

What is inertia?
Inertia is the name for the tendency of an object in motion to remain in motion, or an object at rest to remain at rest, unless acted upon by a force. -physics.about

Force is a quantitative description of the interaction between two physical bodies, such as an object and its environment.

Force is proportional to acceleration. -physics.about

and

Acceleration is the rate of change of velocity as a function of time. It is vector. -physics.about

and

Velocity is a vector measurement of the rate and direction of motion or, in other terms, the rate and direction of the change in the position of an object. -physics.about

So using those exact definitions in one sentence we get this:

Mass is an amount of a proportion of an interaction and a rate of change of the change of the rate and direction of the change in position of an object as a function of time. In other words, mass is the movement of motion of an object over time. Clearly the mathematician confuses concepts and objects and moves motion around with his pencil in his equations.

And what about this mysterious word "object" we have been using? We used About.physics for the other definitions, but it has nothing to say about this word object, so lets use Oxford's Dictionary: a material thing that can be seen and touched.

Finally we get to motion:
In physics, motion means a continuous change in the position of a body relative to a reference point, as measured by a particular observer in a particular frame of reference. In other words, any physical movement or change in position or place. - Wiki Answers

Newton's second law of motion can be formally stated as follows:

The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object. - PhysicsClassroom.com

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So here we are back at the beginning and no closer to understanding any of it. At least relativists are being consistent in one respect; mass, object and motion require an observer.

We see, in the articles on mass in the Files Section at RSM, that the equations for mass are circular. We see very clearly here that the definitions for mass are also circular. We also note that, by definition, an observer is needed for mass, object and motion.

But if every”thing” has mass and mass is equivalent to energy, then don't we need to understand what is meant by energy?

As a child my science teacher told me this:

Energy is the ability to do work. Energy is mathematically quantified as follows: 1 J of “energy”= 1 W s = 1 kg m^2/s^2

Energy relates matter, its motion, the distance it has traveled, and how much time it took for it to get there. Energy is not a thing. It is relational, in other words, a concept.

Maybe the definition has changed. Let’s see:

”In physics, energy is a property of objects which can be transferred to other objects or converted into different forms. The "ability of a system to perform work" is a common description, but it is misleading because energy is not necessarily available to do work.” - Wiki

OK, I can transfer my energy to a rock by picking it up and raising it above the ground, or throwing it through a relativist’s window.

But what does it mean when we say a rock sitting on the ground has potential, or stored energy? How can a rock have, or store energy if it is a concept? I store potatoes on a shelf under the kitchen counter. AND how do I transfer energy to the rock by picking it up or throwing it?

From Wiki: “In physics, potential energy is energy possessed by a body by virtue of its position relative to others, stresses within itself, electric charge, and other factors.”

What is kinetic energy?

Kinetic energy is energy that a body possesses by virtue of being in motion.

So I transferred my energy by being in motion (throwing the rock). Since the rock was in motion its potential energy, while just sitting there on the ground, became kinetic energy because it was now moving. But what was actually transferred? Stresses within me, electrical charge, other factors? When the rock went through the relativist’s window the rock transferred its energy to the window which broke into many pieces and fell to the floor. Unless Mrs. Relativist adds her energy to the broken glass’s potential energy, the glass will lie there forever because Mr. Relativist never does physical work.

The sun provides energy to a spinach plant which needs it to grow. Solar energy is transferred to the plant and by virtue of photosynthesis the sun’s energy becomes sugar in the spinach leaf, and the sugar becomes ATP through cellular respiration. A rabbit comes along and eats the spinach leaf . Now the solar energy which became sugar can become rabbit energy. The rabbit hops around looking for more spinach to eat in Mrs. Relativist’s garden.

Sun, spinach, sugar, ATP and rabbit are the objects. But energy is the transfer of motion. Motion is two or more locations of an object. Transfer is an act of moving something to another location. Huh? So energy is moving motion. Grammatically incorrect and irrational!

At least the phiz whiz is consistent. AND we see that mass which is motion in motion, and energy which is moving motion are the same thing!

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