The purpose of science - part 1
The purpose of this document is to study science only with experiments which use light signals. As such only clocks which operate with light signals are studied. Atomic clocks are not considered because they belong to quantum mechanics. See also book "Gravitation" page 393. The movement of objects (gravitation) is not considered.
The behaviour of moving objects is studied in this document: The purpose of Science - part 2. In that document light signals are not used.
The purpose of science at large scale is to predict the future of the evolution of the universe as acurate as possible.
The purpose of science at small scale is to predict the evolution of any process as accurate as possible.
The question to answer is: what are the rules to follow, to perform science properly.
A different definition of the purpose of science is to explain something. To explain in general means to define the cause however it can also mean to describe something in more detail.
The discovery of the telescope (improvements) allowed Galileo to draw more detailed sketches of the surface of the Moon.
In order to do science claims or concepts are used.
One of the rules is of science is that any claim or concept used should make a clear distinction between at least two different physical situations.
It is also important to make a difference between measures versus calculated.
- As such it does not make sense to claim that the speed of light is constant (every where in the universe)
It only makes sense to claim that the speed of light can vary based on certain external influences or conditions.
It should be mentioned that light is strictly speaking only a condition when a photon hits a human eye. For the rest the behaviour of a photon is a physical process.
- It does not make sense that nothing in the universe is absolute. If you make such claim, the word absolute, implying something physical, has no value. In fact the word absolute can be removed.
- It also does not make sense to claim that all velocities or speeds are relative.
- It does not make sense to claim that only mathematical equations or relations can be absolute. Mathematical concepts are used to describe physical processes, but by themself are not part of a physical process.
- It does not make any sense to claim that each clock always tick at his own rate.
It only makes sense (if that is the case) to claim that the ticking rate of a clock can vary, based on certain external conditions.
- Measures is all what is directly physical is first hand established, using a measuring device. The result is a measurement value.
- Calculated is a mathematical operation which involves a combination of measurement values and calculated values. The result is a mathematical operation.
A calculation can also be the combination of a measured value and a conversion factor.
2. Accepted facts
A second rule is to start from certain accepted facts.
Ofcourse everyone can challenge what these 'facts' are.
A scientific investigation can starts as follows:
See for more below at 4. Outline to do celestial mechanics
- There exists an universe and the universe itself is an amalgation of objects. There are objects of all differents sizes and composition. The largest we call black holes and stars, the smallest dust particles and even smaller.
- We humans define something what we call the state of the universe. The state of the universe defines a description of the positions of all the objects in the universe at any one particular moment.
- The state of the universe is not static but dynamic and changes continuously. As such the composition and number of objects also changes continuously.
All over the universe changes take place and many of these changes are identical. It is the object of science what these differences are and how these processes can be influenced or controlled in a specific direction.
- One of the most special objects which inhabitat the universe are human beings. We humans define that there exists a present or a now. This concept is clocely linked to the state of the universe.
- Humans have something special and that is that they have a mind.
Using their mind humans can remember what has happened in the past and can predict what will happen in the future.
It is important to point out that there exists no past and no future.
3 How to perform science properly
Now we come to the issue is how to perform science properly.
- All of science starts with performing observations and measurements. This is a very important step performed by humans using instruments. The importance should not be under estimated.
- The second step is to perform experiments. Experiments are specific important to get more detail about what is involved. An important part of experiments is to describe in full detail how the experiment is performed and what the results are. This is important such that other people can repeat the same experiments and or improve the experiment.
- The third step is to describe the results of the experiments in a mathematical form or equation. It should be mentioned that most experiments or processes, cannot be described by mathematics. Processes that can be described we call stable, those that cannot be described we call unstable or unpredictable (chaotic). It should be mentioned that stability is caused by the internal physical conditions inside the processes and not by the mathematics or laws that descibe these processes. Specific it should be mentioned that what we call the laws of nature is not something that exists out there. All these laws are slowly invented and improved mainly by performing experiments.
- The fourth step is, it is not really a step, is to repeat these steps in order to improve accuracy or to find new laws with better describe the observations or experiments.
4. Outline to do celestial mechanics
That does not mean we (humans) can not learn from the past nor that we cannot predict the future. In fact we can predict the future specific when we can describe the results of experiments in some mathematical way.
The first step in the field of celestial mechanics is to measure the positions of the objects we want to study in a certain coordinate system.
- The problem is that in principle you can do all these measurement at the same moment. However that is not what we want.
What we want is that all these observations should reflect the same moment. It should be mentioned that to do that requires very difficult calculations. That is the second step.
- The third step is to calculate the speed of each object.
To do that you need a clock . The problem is a clock is also a physical process, which in turn requires detailed investigations how it operates under difficult conditions.
From past experience we know that moving mechanical clocks effect the ticking rate. They can even stop ticking. In this document the main attention is on clocks which internal operation (oscillation) is based on light signals.
- As a final remark here I want to mention that in order to do step 2 you also need a clock
5. Experiments with 2 Space ships.
The purpose of these experiments is to demonstrate and use the information of paragraph 1 and 2.
We start from the following accepted facts:
Consider an almost empty universe with only small objects. Each object is a space ship. All the objects are considered at rest.
Gravitation is not considered
Only one coordination system is considered.
The speed of light is considered to be the same in all directions.
Consider a point O as the origin of a co÷rdination system.
This can also be an object, a space ship, a clock or an observer.
- Consider point A at a distance l in the -x direction from point O. In this case point A is also space ship A
- Consider point B at a distance l in the +x direction from point O. In this case point B is also space ship B.
What this means that we have defined three points A,O and B at equally spaced distances l.
- At t0 we send a light signal, starting from point O towards point A and point B. These lightsignals will reach the points A and B simultaneous at t1. It is important to understand that these are two simultaneous events.
- At each point A and B there is a mirror. The reflection signals will reach point O simultaneous at t2.
This is the end of experiment 1.
Picture 1 shows the situation what happens when at a point O, halfway between two points A and B, a light signal is emitted towards those two points.
- These two light signals reach both points simultaneous at t1, where they are reflected.
- At t2 both signals meet each other at point O.
When Display 2 is selected, the display shows: the situation when the engines in the opposite direction are fired.
Experiment 2 is the same as Experiment 1 except with the only difference that at the moment t1 when the two light signals reach the two points A and B the engines of the space ships A and B will be fired with a standard burst in the +x direction.
This means is that both space ships will move with the same speed v1 in the + direction.
- What that also means if there was a fixed connection (length 2l) between the two space ships A and B before the engines were fired at t1, this distance will be maintained after they are fired at t1.
- Suppose there are also two identical clocks on each space ship A and spaceship B. Both these clocks are reset and started at t1. If that is the case than both these two clocks will run simultaneous.
(Both the two moving clocks A and B will run slower compared with two clocks A and B with stayed at rest)
Picture 2 shows almost the same information as Picture 1 except:
- That at t1 the engines of both Spaceship A and Spaceship B are fired with the same power boost.
That means both space ships have the same speed towards the right.
- The two green lines show the path of each spaceship
- It is important to observe that the length of the distance AB and CD are the same.
What that demonstrates is that the experiment is symmetric
Experiment 3 will start where Experiment 2 ended. That means we have two space ships A and B moving with the same speed v1 at a constant distance 2l apart. That means the two space ships are not at rest.
- Now we are going to repeat more or less the same experiment as Experiment 1.
We are defining a point O half way between the two points (space ships) A and B. This now becomes a moving point O.
- At t3 we send a light signal, starting from the moving point O, towards point A and point B. These two events when they reach point A and B are not simultaneous.
Space ship A will move towards point O and Space ship B away from point O. That is why the lightsignal will reach Space ship A first and Space ship B later. As such the moment that point A is reached, is called t4 and the moment that point B is reached, is called t5.
- At each point A and B there is a mirror. The reflection signals will reach point O simultaneous at t6.
As such from the point of view of an Observer at point O there is no difference between Experiment 1 and Experiment 3.
This is the end of experiment 3
Picture 3 what happens next after the engines of both space ships are fired
- Again at a point halfway between the point A and B (at point O) a lightsignal is send towards the two space hips.
- At t4 and t5 point signals are reflected. They again meet point O simultaneous.
Experiment 4 is the same as Experiment 3 except with the only difference that at the moment when the two light signals reach the two points A and B the engines of the space ships A and B will be fired with a standard burst in the +x direction.
What that means is that there after both space ships will move with the same speed v2 in the +x direction.
However there is a distinct physical difference between Experiment 2 and Experiment 4:
In Experiment 4 the two engines will not be fired simultaneous: The engine of space ship A (at the back) will be fired first at t4 in the +x direction and the engine of space ship B (in front) later at t5.
- What that also means if there is a fixed connection (length 2l) between the two space ships A and B before the engines were fired at resp t4 and t5, this distance will become shorter after they are fired. This is because space ship A, being fired first, moves in the +x direction towards space ship B.
- However there exists also a different possiblity. This is the case when the engines of the space ships A and B will be fired with a standard burst in the -x direction.
This means is that there after, both space ships will move with the same speed v3 in the -x direction.
Also in this case the engine of space ship A (at the back) will be fired first at t4 in the -x direction and the engine of space ship C (in front) later at t5.
- This also means if there is a fixed connection (length 2l) between the two space ships A and B before the engines were fired at resp t4 and t5, this distance will become longer after they are fired. This is because space ship A, being fired first, moves in the -x direction away from space ship B
When Picture 4 is selected the opposite is the case. In that case the engines are fired in the opposite direction as previous.
Picture 4 shows what happens next after Picture 3.
- At t4 and t5 the engines of each spaceship are fired in the same direction as previous with the same engine boost.
- The new path for each engine is indicated with the red line.
- In Picture 4 you can see, that the enigine of spaceship A is fired at t4, before the engine of space ship B is fired at t5.
- What that means is at t5 the distance between both spaceships (the length CD) is shorter than before (the distance AB).
- What that also means, if AB was the length of a rod, with two engines at both ends, that after t4 the length of the rod will be compressed and becomes shorter.
What that means is at t5 the distance between both spaceships (the length CD) is longer than before (the distance AB).
- What that also means, if AB was the length of a rod, with two engines at both ends, that after t4 the length of the rod will be stretched and becomes longer.
- At the end of experiment 2 is written:
- Both the two moving clocks A and B will run slower compared with two clocks A and B with stayed at rest
Consider a set of 4 clocks (A0,B0,C0 and D0) at rest, equally spaced and a set of 4 moving clocks (A1,B1,C1 and D1) also equally spaced. There is also a separate point O which takes care the the clocks are properly synchronized
The set of clocks at rest (A0 etc) run synchrone and so do the moving clocks (A1 etc).
Because the moving clocks move in the +x direction they can meet (coincide) clocks at rest.
The first time this will happen, clock A1 will meet clock B0, clock B1 will meet C0 and clock C1 will meet D0.
The second time, clock A1 will meet clock C0, clock B1 will meet D0 and clock C1 will meet E0.
All these meetings (events) will happen simultaneous.
Clock count observations of all meeting events will reveal that all clocks show the same behaviour.
The first meeting all clocks at rest (A0 etc) show 100 counts and all moving clocks (A1 etc) show 90 counts.
The second time all clocks at rest show 200 counts and all moving clocks 180 counts.
Using these numbers you can calculate the speed of the moving clocks clock relative to the speed of light
- You can also perform the same experiment in the opposite direction. The results will be the same.
What this means is that this is a symmetrical experiment and a confirmation that the speed of light is at least the same in the +x and -x direction.
- Experiment 4 resembles experiment 2 but it is basically different.
What we have is a set of equally spaced moving clocks (A1,B1,C1 and D1) with a speed v1 and a set of equally spaced moving clocks (A2,B2,C2 and D2) with a speed v2 (or v3). The clocks are renamed to make a distinction.
- The observers A1 etc can consider them self at rest, but physical they are not.
For the observers (space ships) A2 etc this is not the case. They are moving and have a certain speed, because as part of experiment 4 the engines are fired.
Now there are two possibilities.
The first possibility is that the engines of the moving clocks A2 etc are fired in the +x direction. In that case the moving clocks A2 etc will meet the clocks 'at rest' A1 etc.
The first time this will happen, clock A2 will meet clock B1, clock B2 will meet C1 and clock C2 will meet D1.
The second time, clock A2 will meet clock C1, clock B2 will meet D1 and clock C2 will meet E1.
- The second possibility is that the engines of the moving clocks A2 etc are fired in the -x direction. In that case the moving clocks A2 etc will meet the clocks 'at rest' A1 etc.
The first time this will happen, clock B2 will meet clock A1, clock C2 will meet B1 and clock D2 will meet C1.
The second time, clock C2 will meet clock A1, clock D2 will meet B1 and clock E2 will meet C1.
- The result of the first possiblity is that the moving clocks A2 etc will show a lower clock count as the assumened at rest clocks A1 etc.
The result of the second possiblity is that the moving clocks A2 etc will show a higher clock count as the assumened at rest clocks A1 etc.
That means the result is asymmetric.
This in turn means that if you perform this experiment and if the result is asymmetric that the considered clocks at rest A1 are not at rest and that in this case the moving clocks B2, fired in the -x direction, are a better choice to be considered at rest.
Reflection 1 - Experiments with 2 or 4 Space ships
What the experiments 1 to 4 with 3 Space ships demonstrate is that the result of the experiment is different if the 3 Spaces ships are at rest (have a speed a speed v=0) or are moving.
The easiest way to demonstrate this is when the three space ships are physical connect by means of rods.
When initially the space ships are at rest and when the rockets are started, using common synchronization signals, there are no internal forces in the connection rods between the space ships.
When initially the space ships are not at rest and when the rockets are started, using common synchronization signals, there are internal forces operating in the connection rods between the space ships.
What experiment 5 demonstrates is that a clock at rest ticks faster compared to a moving clock.
This behaviour is symmetric independent of the direction of movement. A moving clock always ticks slower compared to a clock at rest.
What experiment 6 demonstrates is, if you start from a moving clock and you assume that this clock is at rest, the behaviour (its clock count) depents in which direction the clock is moved. What that means is that there always is a clock which counts faster.
For more detail select this link:
Article Review On the behaviour of Moving Bodies Appendix 2
Reflection 2 - Phase 3
The 6 experiments we can call the phase 1 and phase 2. They involve observations (measurements) and experiments.
The next step is phase 3. In this phase you want to try in a more technical, mathematical way what is involved.
This means to define which parameters are involved in the process and how they interrelate. You could also call this model building. It is all in the name.
The clock used in the experiments operates by means of a lightsignal that bounces back and forward between two mirrors.
The speed of the clock, defines the length of the lightpath. By definition a certain number of counts of a clock at rest is called the number of rest-counts of a clock (n0)
By performing different experiments we can also see that the number of counts of a clock also depends about the direction of the light signal internal inside the clock.
1) When the lightsignal is vertical and the mirrors are parallel to the direction of movement the time
t1 = t0/sqr(1-v^2/c^2) . The number of ticks n1 = no * sqr(1-v^2/c^2)
For more detail see: Book_Review_Spacetime_Physics.htm#ref4
This situation is in agreement with the Lorentz Transformations.
2) When the lightsignal is horizontal and the mirrors are perpendicular to the direction of movement the time
t1 = t0/(1-v^2/c^2) . The number of ticks n1 = n0 * (1-v^2/c^2)
For more detail see: Book_Review_Spacetime_Physics.htm#ref3
What this means is that the mathematics to describe the behaviour of moving clocks is simple and straight forward.
Reflection 3 - Physics versus Mathematics
We live in a physical world, which in reality is continuity of physical processes, which we try to understand, in order to predict the future.
The first step is to perform observations and measurements. The second step is to perform experiments and the third step is to see to what extend mathematical equations (laws) can be used to bring order in maybe what seems chaotic in our measurements.
In that sense it can be important to see what belongs to the physical domain and what to the mathematical domain.
- A reference frame or coordination system in principle belongs to the mathematical domain, but if it is occupied with physical objects in order to measure its position it becomes part of the physical domain.
- The position of an object is always defined by 3 co÷rdinates which indicate position and one parameter which indicate time.
- Velocities are part of the mathematical domain, because a velocity is calculated quatity. vx = (x1-x2)/(t1-t2)
Even if a velocity is a parameter of a physical object they still belong to the mathematical domain.
It should be emphasized that (in principle) the speed of an object at every position along its path, has a different value.
- The velocity of light is a calculated quantity and belongs to the mathematical domain.
- It should be emphasized that concepts like v=v1+v2, v= v1-v2, v=c+v1 and v=c-v1 clearly belong to the mathematical domain. They are not linked to any physical object.
- The clock count of a clock is a physical quantity (based on the internal operation of the clock and the physical dimensions of the clock).
The speed of a clock is a calculated quantity (as a function of the clock count). The time of a clock is also a calculated quantity.
- Accelerations are also part of the mathematical domain.
- Special Relativity uses complex numbers.
It defines s^2 = r^2 + (i*c*t)^2 or s^2 = r^2 - (c*t)^2
All of this (spacetime) belongs to the mathematical world.
- Newton's law belongs to the mathematical world.
The final calculated (predicted) positions of objects belong to the physical world.
- The concept of mass is a calculated parameter.
Calculation of mass requires for example Newton's Law.
As such it is strange why SR uses the concept of mass. It is even more strange why it uses the concept of rest mass, while in order to calculate the mass of an object you need a set of masses in isolation or equilibrium
- The periodic table of all the elements belongs to the physical domain.
This paragraph about physics versus mathematics has a certain reason. The main reason is to what extend physical processes are controlled or governed by mathematics. I doubt that.
We live in a physical world, surrounded by physical processes. What we want is to understand how these physical processes change and how they interrelate. Starting point is that many processes are identical or almost identical resulting in different outcomes. It are the details we want to study and how we can influence these processes.
The processes can be defined in three categories: First, global processes which involve the total universe, centered around the concept of stars. Secondly, local processes centered around the earth. The main guided process is the evolution theory. Finally human based processes and all what has to do with living creatures.
The main characteristic of global processes i.e. the movement of the stars and planets is that they are stable. This allows that these processes can be described using mathematics, but that does not explain why these processes are stable.
The main reason is that the distances involved are large, the speeds involved are small and that all the stars turn in the same direction. That means the chance of collision is small.
At the same time if the size between two objects is large, and the radial speed (of the small object) is small, the large object attracts the small object and both will collide. This behaviour is (partly) described by Newton's Law but does not physical explain this behaviour. A physical explanation is the concept of gravitons, but that explanation is not accepted by everyone.
The problem with Newton's Law is that the forces involved act instantaneous, but that is inconflict with the idea of gravitons and with certain observations (The planet Mercury).
A different explanation is the combination of SR and GR and the concept of spacetime. As mentioned above this involves complex numbers and the mathematical concept of invariance. The question is, if that way leads to a physical explanation?
SR and GR start from two postulates: (1) that the laws of physics are the same in all inertial frames and (2) that the speed of light is the same in all directions or constant.
You can ask your self the question how can you use the first postulate (which by itself is also a law) while the purpose of science is to unravel the so called laws of physics.
In this document the behaviour of clocks are investigated. Both postulates are not used.
Created: 23 March 2020
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