Question 1

What is a law ?

Question 2a

What is a theory ?

Question 2b

What is a theory of everything ?

Question 3

What is a paradox ?

Question 4

What is a thought experiment ?


The purpose of this question is to define certain basic concepts which are relevant for understanding.


Understanding is based on concepts like: Laws, Theories, Paradoxes and Thought Experiments.
Newton's Law is an example of a Law
The Special and General Relativity Theory are examples of a Theory


About Law

A law is a description of the physical reality solely based on observations. This description can include constants.

One of the most famous laws is Newton's Law.
Newton's Law is in the form of:

F = G * m1 * m2 / ( r * r )

Accordingly to the definition, the above form of Newton's Law is not correct, because G, m1 and m2 are calculated values. Calculated values are calculations based on observations. In order to make Newton's Law a true law, the calculated values G, m1 and m2 have to be replaced by true observations.

In order to explain the concept what defines a true law, a simulation in the form of a program in Quick Basic, is supplied.
To get a copy select:TWO_BODY.BAS
In this program the movements through space of two object's m0 and m1 are showed. The initial observations are three positions of m0 at equal intervals and two positions of m1. The value of G has no influence on this movement.

About Theory

A theory is a predicted description of the physical reality; of something new.
When the actual predictions are done to prove the theory than the name should be changed into Law.

About a Theory of everything

A theory of everything is in principle one long sentence which explains (describes and solves) everything.

The author does not believe that the reality can be captured in one "sentence" with any true significance.

About Paradox

A paradox starts with two descriptions or stories of the same physical reality or same events. The outcome of the stories is different, meaning one of the stories contains an error. The question is: which story.
A very famous paradox is: The Twin paradox.
It is the opinion of the author that the understanding of the physical reality should not be based on Paradoxes.

The Two Clock example.
The two clock example is an experiment about the behaviour clocks.
Consider two clocks A & B. Both clocks will travel in a rocket through space and will return after one year, Earth time, back to base. Clock A will travel at low speed and Clock B will travel at high speed.
At the end of each Earth day a light signal will be transmitted from earth. This allows each space ships to detect the completion of one year.
Question: When the two clocks return back to base are all the clocks involved the same ?
That means: Earth time, time of A and time of B.

About Thought Experiment

A Thought Experiment is a description of an experiment which can be described but which can not be performed in the reality.
A famous Thought Experiment is. Schrödingers Cat .
It is the opinion of the author that the understanding of the physical reality should not be based on Thought Experiments.



Last modified: 5 January 1996

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