Relativity Theory after 2019: Many-Minds Relativity.

Recent posts show that adoption of the 2019 SI meter Standard makes Einstein's Special Theory of Relativity SR void of physics, since its basic postulate of the same speed of light for all (inertial) observers, after 2019 simply is an agreement or standard to be followed by all (inertial) observers and not a statement about physics. 

The version of relativity theory, which makes sense as a theory about physics under the 2019 SI meter standard, is Many-Minds Relativity MMR.

In MMR Newton's 2nd Law takes the following form for a stationary observer O following the 2019 SI Standard assuming normalisation to unit speed of light: 

• $\frac{m}{1+v}a=F$       (N2)

where $v(t)=\frac{dx}{dt}$ is velocity with $x(t)$ position, $a(t)=\frac{dv}{dt}$ is acceleration, $m$ is mass, $F(t)$ force and $t$ time (measured by a 2019 SI Standard caesium clock). This describes the motion along an $x$-axis of a body of mass $m$ subject to a force $F(t)$, receding from O if $v>0$ and approaching O if $v<0$ with $v>-1$. 

We see that (N2) appears, compared to the usual 2nd Law $ma=F$, with smaller mass $\frac{m}{1+v}$ if $v>0$ and bigger mass if $-1<v<0$. 

Under a constant force $F=1$, this allows a recession velocity $v(t)$ to increase exponentially with $t$ eventually attaining a speed (much) bigger than the speed of light, while in approach with $F=-1$, $v(t)>-1$. The recession case connects to the Nobel Prize in Physics in 2011 "for the discovery of the accelerating expansion of the Universe".

If now since 2019 SR is void of physics, this makes the element of SR present in Einstein's General Theory of Relativity GR also void of physics. What remains of GR is then the Equivalence Principle which GR shares with Newtonian Mechanics NM. Maybe then NM + MMR is enough? Since both SR and GR are very difficult to understand for most people, this could be greeted as a relief?

The shift to 2019 SI Standard appears to give fundamentally new perspectives on modern physics. 

PS1 Recall that the SR version of Newton's 2nd Law takes the form 

• $\frac{m}{\sqrt{1-v^2}}a=F$ 

which has the same form in recession and approach and in particular keeps $v<1$ as if the speed of light cannot be surpassed, which is not what is observed for far away galaxies receding with $v>10$.

PS2 Recall that GR is incompatible with quantum mechanics, which is a main trouble of modern physics, while NM+MMR is compatible with quantum mechanics.

    

Gravitation in Free Fall

Gravitation is in modern physics described by Einstein's General Theory of Relativity GR, and in classical physics by Newton's Mechanics NM including Newton's 2nd Law and Newton's Law of Gravitation. 

GR reduces to NM when matter/mass velocities are small compared to the speed of light, which covers planetary systems (Solar System 30 km/s) and galaxies (Milky Way 100 km/s) compared to 300.000 km/s. 

In coordinate free form NM is based on the following basic principles: 

1. Gravitational force is conservative (zero work from motion in closed loop).
2. Conservation of gravitational force (divergence of force = mass).                     (P)
3. Conservation of momentum (Newton's 2nd Law).
4. Conservation of mass. 

In Eulerian form in Euclidean space-time coordinates $(x,t)$, (P) take the following form assuming only gravitational force (free fall motion): 

1. $F =\nabla\phi$
2. $\nabla\cdot F=\rho$
3. $\dot m+\nabla\cdot (um)+\rho\nabla\phi =0$                          (PE)
4. $\dot\rho +\nabla\cdot m=0$ 

where $\phi$ is gravitational potential, $F=\nabla\phi$ gravitational force per unit mass, $m$ momentum, $\rho$ mass density and $u=\frac{m}{\rho}$ is matter velocity all depending on $(x,t)$. Different space coordinates can be used (spherical, cylindrical et cet), which transforms (PE) but not (P). 

In NM based on (P) there is no limit on the size of matter velocity. The question is if GR contributes something of importance when matter velocity is not small and GR is different from NM?

What can be wrong with NM as being based on (P)? What can be wrong with (P)? 

We compare (PE) with the presentation of GR in the book Gravitation by Misner, Wheeler and Thorne over 1250 dense pages. Is this Gravitation in free fall?

It is essential to understand that real physics cannot depend on specific coordinate systems used to express laws of physics. In particular, the physics of gravitation, that is how matter interacts with gravitational forces, cannot depend on choices of coordinate systems made by humans. The motion of the planets in our Solar system cannot be influenced by the choice of coordinate systems used by scientists to track their motion. But Einstein was obsessed with coordinate systems when setting up both the special and general theory of relativity. 

As recalled in recent posts, GR and NM both satisfy the Equivalence Principle stating that inertial mass is equal to gravitational mass and both have the same speed of light in all inertial systems. 

     

The Equivalence Principle of General Relativity

Bodies of different mass fall the same way.

The pillars of modern physics are quantum mechanics and Einstein's General Theory of Relativity GR, which is based on the following Equivalence Principle EP:

• inertial mass = gravitational mass.                          

In Newtonian Mechanics NM including Newton's Law of Gravitation, EP is not an assumption but instead a necessary consequence of the fact that in NM, as experimentally verified by Galileo dropping different objects from the tower of Pisa while supplying also a theoretical justfication: 

• all bodies independent of mass accelerate the same way in proportion to gravitational force.  

More precisely, with A acceleration and F gravitational force per unit mass, in NM we have 

• A = F

which we can write 

• MA = MF

where M is mass, as an expression of Newton's 2nd Law: mass x acceleration = force. We see that $M$ appears on both sides as an expression of EP. 

Summary: EP is automatically satisfied in NM. It does not make sense in NM to introduce EP as an assumption. On the other hand, EP is an assumption of GR. EP is self-evident in NM but not so in GR, where (P) is made into assumption as if it is possible that inertial mass is different from gravitational mass. This makes GR into a strange perturbation of NM with the following question: What makes GR different from NM when they share the same EP? 

How Do We Know the Names of the Stars?

Recent posts have exhibited a fundamental confusion or ambiguity concerning the basic Postulate of Einstein's Special Theory of Relativity SR stating: 

• The speed of light is the same for all (inertial) observers.     (P)

The question is if this is an analytic statement or definition/convention/agreement/stipulation made by human minds and as such has no value as true or false, or if it is a synthetic statement about some physical reality which may be true or false. 

We may compare with the following innocent question, which can be posed by an innocent child when looking into the night sky:

• How can we know the names of the stars (when they are so silent and far away)?

The natural answer from an adult is that the stars have been given names by human minds and so represent definition/convention/agreement/stipulation as analytic statement. 

But in the mind of the child it may also appear to be possible that somehow the names of the stars have been assigned by some Creator as synthetic statement and that it is up to human minds to try to somehow figure out the names. To a child it would be like asking the name of a new person unknown to the child. Of course the idea that somehow stars have names on their own independent of human name-giving appears arcane to an adult, but the idea is possible. Of course, a child would not direct a question about name to a dog. The question (to an adult) would instead be: What is the dog called?

Let us now return to (P): 

1. As analytic statement as definition/convention/agreement/stipulation, it corresponds to the SI standard defining meter in terms of travel time of light. This corresponds to stars being given names by human minds.  
2. As synthetic statement it means that somehow light propagates with its own speed independent of human minds.  This corresponds to stars somehow having names independent of human name-giving.   

We understand that 2 is strange and can only reflect a very innocent childish mind. Nevertheless, this is the interpretation as basic postulate of SR following Einstein: The constancy of the speed of light for all observers is not simply an agreement as 1, but a physical fact which Einstein assumes to be true. 

Einstein thus views (P) to both be analytic and synthetic. But this is contradictory since analytic and synthetics statements have different nature as concerns being true or false. This is the root to all the confusion and mystery surrounding SR.

Recall that with the 2019 SI meter standard, (P) is definitely analytic and not synthetic. To Einstein in 1905, (P) was synthetic. Things have changed. SR is no longer needed after 2019. Physics has become simpler. Einstein can rest in peace.

Unthinkable that Newton's Theory of Gravitation is Not Correct

The grandest achievement of human intelligence is Newton's Theory of Gravitation NG which can be expressed as a Poisson/Laplace equation:

• $\Delta\phi =\rho$             (N)

where $\phi$ is gravitational potential and $\rho$ mass density depending on a Euclidean space coordinate $x$ and time coordinate $t$ and $\Delta$ is the Laplacian differential operator with respect to $x$, and the gradient $\nabla\phi$ is gravitational force. 

(N) is a mathematical/logical consequence of 

1. Gravitational force $F$ is a conservative force with work independent of path and so of the form $F=\nabla\phi$. 
2. Conservation of force expressed as $\nabla\cdot F=\rho$ leading to (N). 

It is unthinkable that gravitational force is not conservative (not 1) and also unthinkable that it is not conserved (not 2), and so it is unthinkable that (N) is not the connection between gravitational potential and mass density. If there is an experiment/observation/theory contradicting (N), then there must be something wrong with the experiment/observation/theory. 

It is unthinkable the NG is not correct. God must have created the World from mathematical principles.

I have discussed (N) in many posts on New View on Newtonian Gravitation and New Newtonian Cosmology.  

Einstein said that his biggest mistake was the presence of cosmological constant in his General Theory of Relativity GR presenting an alternative to NG.  

The biggest mistake of modern physics was to throw out NG and replace it with GR, which has put modern physics in a permanent state of crisis. 

Einstein is viewed to be the greatest physicist of all times, greater than Newton, because Einstein is viewed to have shown that NG is wrong. 

But we have just understood that it is unthinkable that NG is wrong. The conclusion can only be that Einstein's claim that NG is wrong, cannot be true. 

This means that it is unthinkable that Einstein is correct. It is time to return to Newton and let Einstein fade away and so proceed to get out of the present state of crisis of modern physics. Ok? 

Gravitational Waves as Fiction

We recall the following Newtonian model of the Universe from this recent post:

• $\rho=\Delta\phi$                        (N)             (conservation of gravitational force)
• $\dot\rho +\nabla\cdot m =0$                        (conservation of mass)
• $\dot m +\nabla\cdot (um) +\rho\nabla\phi =0$    (conservation of momentum)

describing a (zero pressure for simplicity) distribution of matter subject to gravitation, where $\rho$ is mass density, $\phi$ gravitational potential, $\nabla\phi$ gravitational force per unit mass, $m$ is momentum, and $u=\frac{m}{\rho}$ is material velocity, all depending on a Euclidean spatial coordinate $x$ plus time $t$ with the dot representing differentiation with respect to time.

We focus on the connection between gravitational potential $\phi$ and mass distribution $\rho$ expressed through Laplace/Poisson's equations (N), which formally involves infinite speed of propagation into $\phi$ from a local change of $\rho$. Let us compare with the following wave equation as a Neo-Newtonian variant of (N) with finite speed of propagation $c$

• $\frac{1}{c^2}\ddot\phi -\Delta\phi = -\rho$.            (NN)

Let us now compare (N) and (NN) in a situation where the mass distribution changes/moves with velocity $v$ which is small compared to $c$, which is the typical situation within a planetary system and collection of stars or even galaxy. This means that $\nabla\cdot m$ is small of size $v$, which means that $\dot\rho$ is small of size $v$. We conclude from (NN) that $\dot\phi$ is small of size $v$ and so also $\ddot\phi$ assuming $\nabla\cdot\dot m$ is small of size $v$. This means that the difference between (N) and (NN) is of size $\frac{v}{c^2}$ thus very small.

We conclude that even if we extend (N) (without gravitational waves) to (NN) (with gravitational waves), the difference is very small. This is in line with the LIGO experiment supposedly identifying a very very small gravitational wave from a very very large source. Indeed, very very small. More precisely from LIGO documentation:

• For physicists, a strong gravitational wave will produce displacements on the order of $10^{-18}$ meters - this is 1000 times smaller than the diameter of a proton. Waves of this strength will be produced by very massive systems undergoing large accelerations, like two orbiting black holes that are about to merge into one. Since systems like these are rare, these sources will be light-years away. Therefore, the search for gravitational waves is seeking the minute effects of some of the most energetic astrophysical systems from the depths of the universe.

We thus have theoretical and observational support of an idea that we can view gravitational waves to be fiction,  which we do not have to worry about. This makes theory simpler and also computational simulation, since (N) is much simpler to solve computationally than (NN), and so makes cosmology simpler. This is a gift from Newton.

Napoleon criticised Laplace, expert in infinitesimal Calculus, for work on infinitely small issues in his administration. Napoleon would probably similarly criticise Einstein for working with infinitely small deviations from Newton's mechanics.

A Contrafactual History of Modern Physics

An early Rangefinder from 1900.

This connects to the recent posts on the 2019 SI unit standard of second and meter.

Suppose the 2019 SI standard had been implemented already say in 1900. This means that from 1900 on length was measured in terms of travel time of light assuming a speed of light of exactly 299792458 meter per second. 

This is how a rangefinder of today works: Send a signal towards an object and measure the time for the reflected signal to come back, assuming a certain speed of light. This would have been possible in 1900. 

Using the SI standard a null result from the Michelson-Morley experiment is to be expected. Each observer "drags along an aether" linked to the observer and defines length from travel time of light under the assumption that light propagates with exactly 299792458 meter per second. 

With an expected MM null result using the SI standard, there would be no reason to invent the new physics of Einstein's Special Relativity SR, because it was motivated by the MM null result seeming to be  inexplicable using the meter sticks/measuring rods envisioned by Einstein. More precisely, what motivated Lorentz to introduce the Lorentz transformation in 1904 (first formulated by Voigt in 1887), was to explain the MM null result as an effect of space contraction in the direction of motion. Einstein picked up the Lorentz transformation in 1905, without reference to Lorentz or Voigt. 

Modern physics as a physics under a SI standard adopted in 1900, would thus be free of SR. Modern physics would thus consist of quantum mechanics added to Newton's mechanics and Maxwell's electromagnetics as a fully compatible combination. This would be a modern physics without the incompatibility of relativity theory and quantum mechanics, as a main trouble behind the present crisis of modern physics.

  

 

Physics as Agreement is Not Real Physics

This is a further clarification of recent posts on units of time and length. 

The International System of Units SI defines 7 base units starting with time (seconds) and length (meter) as a universal system to be used in science and technology. 

The second (s) is defined by taking the fixed numerical value of the cesium frequency, the unperturbed ground-state hyperfine transition frequency of the cesium-133 atom, to be exactly 9192631770.

The meter (m) is defined by taking the fixed numerical value of the speed of light in vacuum to be exactly 299792458 meter per second.

This system can be used at any place of the Universe, as long as there is light in vacuum and caesium-133 atoms to set the units. Very handy and completely universal! 

But there is a caveat: How can we know that the speed of light or frequency of caesium-133 is the same everywhere? Maybe there is light but no vacuum, and maybe the frequency of the caesium-133 atom varies with temperature, pressure and gravitation? 

We must thus be prepared that different observers setting up their equipment under different conditions to set their specific time and length scales, will not agree to the last decimal on measuring something of common interest. This is the same as expecting that different traditional craftsmen may have had a bit different ideas of thumb, feet and yard.

The key question with physics as agreement according to SI, is to what extent different observers using this standard will agree outside the SI standard. In particular, we may ask to what extent different observers moving with different velocities will agree on distances? A partial answer is given in Many-Minds Relativity. As long as velocity differences are small compared to the speed of light, there will be little disagreement on distance, but not so in general.

Summary: It is possible to make an agreement to define length by travel time of light agreeing on a specific speed of light. If you think that this agreement is more than an agreement, that it is in fact real physics established by agreement, then you are fooling yourself. This is what Einstein did with his Special Theory of Relativity. You may test if you have understood by answering the following question: Is it possible that the speed of light in fact is 299792457.99?

With all observers using the same type of caesium clock for which a dependence of inertial motion is unthinkable, there can be no time dilation between inertial observers, which shows that the Lorentz transformation is not physics,  as very well understood by Lorentz, but misunderstood by Einstein. SR is clearly non-physics since 2019, which should have been understood by everybody from the beginning. But Einstein was very smart and fooled a whole world.   

Null Result of Michelson-Morley Experiment vs 2019 SI Meter Standard

This is a further clarification of the recent posts on the 2019 SI definition of length scale.

Einstein's Special Theory of Relativity SR as a pillar of modern physics came out from an effort to explain the Michelson-Morley experiment performed in 1887 with the objective of detecting the presence of a luminiferous aether as a medium surrounding the Earth carrying light waves. The MM-experiment gave a null result (as the most famous "failed experiment") indicating that if there was such a medium, then it must be "dragged along" by the Earth, which was viewed to be very strange. I will return to this below.

More generally, the null result indicated that the speed of light is the same independent of motion with constant velocity, so called inertial motion.  

To maintain credibility, the physics community was in desperate need to explain the MM null result and to this end the FitzGerald–Lorentz length contraction hypothesis was fabricated suggesting a change of spatial scale depending on motion, but that was also viewed as very strange. How could the lenght of a solid bar change with inertial motion. 

Then came Einstein with his SR in 1905 claiming that there is no medium at all required for propagation of light, thus explaining the MM null result from null presence of any medium as a very radical solution as a form of null from null. 

But the physics community did not accept SR until much later long after Einstein himself had distanced himself from SR as being null. What opened physics books to SR was Einstein's General Theory of Relativity GR from 1916 kick-started in 1919 as supposedly experimentally verified by Eddington's solar eclipse experiment.  

The net result is that modern physics is based on SR/GR and quantum mechanics, with a declared formidable success however compromised by the fact that these two theories are incompatible. This ended in a stalemate with no hope to finding a common theory. The result is that modern physics today is in a state of crisis from unresolved incompatibilities.

But in 2019 a new element was brought in by the International Committee for Weights and Measurements (CIPM) setting a new standard for length scale (meter) defined by travel time of light defining the speed of light (in vacuum) to be exactly 299792458 meter per second with time measured by a standard caesium atomic clock. 

This means that since 2019 the length scale for a given inertial Euclidean coordinate system $X$ traveling with a constant velocity with respect to other inertial systems, is determined by sending a light signal from the origin of $X$ and marking distance along coordinate axes by travel time of light assuming a specific speed of light. This means that effectively each inertial coordinate system $X$ serves as a medium for propagation of light at a specific speed, as if the medium is dragged along with the coordinate system. Since there are many different inertial systems,there are many media for light propagation each one at rest with its inertial system. 

This opens to a different explanation of the MM null result than that of Einstein with no medium, as a many-media situation (as suggested already by Ebenezer Cunningham in the 1910s) elaborated as Many-Minds Relativity. 

The MM null result is then explained by the fact that the length scale in each inertial system $X$ is established by travel time of light assuming that it propagates at exactly 299792458 meter per second in $X$. This means that the length scale depends on motion, and the issue is then to assess difference in distance measurements in different inertial systems, which is the topic of Many-Minds Relativity. 

The length scale thus depends on motion, but it does not mean that a solid bar is affected in any way by inertial motion. The bar remains the same but its length changes because length scale changes.  

In orther words, modern physics has since 2019 returned to a pre-SR era with each inertial system "dragging along" its own medium for light propagation, thus elimination the mission of SR. 

The MM null result is thus finally explained in terms of inertial systems"dragging along" media for light propagation, along the original Lorentz idea.      

 

      

Galilean Relativity returns with 2019 Meter Standard

Galileo is back 2019 and Einstein leaves the scene.

The 2019 SI Standard specifies spatial length scale (meter) in terms of travel time of light as measured by a caesium atomic clock under the common agreement that the speed of light (in vacuum) is exactly 299792458 meter per second. 

This means that since 2019 the main postulate of Einstein's Special Theory of Relativity SR of the constancy of the speed of light in all inertial Euclidean coordinate systems moving with constant velocity with respect to each other, no longer is a postulate about physics, but simply an agreement of how to specify the length scale in any given inertial system. This means that SR is void of real physics, since the other postulate of SR is also void of real physics.  

This means that modern physics after 2019 is not the same as before, since modern physic is based on SR which after 2019 is void of physics. 

SR is thus after 2019 no longer a relativity theory about real physics, and it is natural to ask what kind of relativity theory we are facing after 2019?

We then consider two coordinate systems $X$ and $X^\prime$ moving with constant velocity $v$ with respect to each other, sharing a common time $t$ set by identical caesium clocks in the two systems. Let us consider $X$ to be at rest and the origin of $X^\prime$ following the trajectory $x=v*t$ in the space-time coordinates $(x,t)$ of $X$, with the connection $x^\prime = x-v*t$ to coordinates $(x^\prime ,t)$ in $X^\prime$. 

Let us now consider an object $O$ at rest somewhere in $X$ and determine its $x$ coordinate in $X$ by according to the SI Standard sending a light signal from the origin of $X$ and measure its travel time to reach $O$ and then translate that into distance with 1 second corresponding to $299792458$ meter. If the travel time is 1 second, then  $x=299792458$ for all $t$. This will then be the length of a straight bar reaching from $x=0$ to $O$.

Let us now seek to determine the distance from $O$ to the origin of $X^\prime$ at some given time $\bar t$. With the SI Standard in mind we do this by sending a light signal from $x^\prime =0$ and record travel time to reach $O$. The situation is now different since $O$ is not stationary in $X^\prime$ but moves with velocity $v$ with respect to $x^\prime =0$. This influences the travel time making it longer if $O$ is moving away from $x^\prime =0$ and shorter if $O$ is moving towards $x^\prime =0$. 

The effective speed of light in $X^\prime$ vs the moving object $O$ thus changes from $299792458$ to $299792458+v$ meter per second, if we for simplicity assume that $v$ is parallel to the direction from $x=0$ to $O$.  If the travel time is 1 second, then the distance to $O$ in the $X^\prime$ system is $299792458+v$ meter, to be compared with $299792458$ in $X$. 

If $X$ and $X^\prime$ refer to human observers, then typically $\vert v\vert <1000$ and so distance in $X$ and $X^\prime$ will agree to 6 decimals.

We thus find that with the new SI Standard distance is relative as being different in $X$ and $X^\prime$ with a very simple conversion depending on the mutual velocity $v$. 

We are then led to define the "rest distance/length" as the distance measured in a system where the $O$ is at rest. 

The SI Standard thus brings physics back to Galilean relativity dismissing Einstein's SR with all its heavy baggage of Lorentz transformation, time dilation, space contraction, rest mass and myriad of paradoxes which nobody can really understand, only pretend to understand.  

This amounts to a form of self correction formed by the International Committee for Weights and Measurements (CIPM) seeking to form a useful working Standard and then (without direct intent) happening to eliminate SR from physics since it is not useful. 

We should thank CIPM for making life so much easier for both professionals, students and laymen. After an impasse of SR over 114 years, rationality is back to physics! 

But this message has not yet reached the theoretical physics community still struggling to make sense of Einstein's theories. In particular, in one quick step it eliminates the main road block to advancement of modern physics as the incompatibility of relativity theory and quantum mechanics. 

For more details of Galilean relativity in our time, see Many-Minds Relativity.

New 2019 SI Standard requires Restart of Modern Physics

This is a clarification of the latest posts on Einstein's influence on modern physics.

The SI Standard since 2019 defines length scale (meter) in terms of travel time of light assuming that the speed of light is exactly 299792458 meter per second, while time scale (second) is set by a caesium clock.  

This means that different observers using different spatial Euclidean coordinate systems traveling with different constant speeds with respect to each other, using different inertial systems, will have to adjust their meter scale to an agreed speed of light of 299792458 meter per second according to the 2019 SI Standard.  

This means that the basic postulate of Einstein's Special Theory of Relativity SR stating that the speed of light is the same in all inertial systems, is no longer a statement about physics, which can be true or false, but simply a definition or standard or agreement or convention and as such stating nothing about physical reality. 

This means that SR since 2019 has nothing to say about real physics and so has no longer any meaning as a physical theory. 

This means that modern physics has to make a fresh restart since modern physics is based on SR which no longer is a physical theory. 

The real question confronting physicists after 2019 is to what extent observations in different inertial systems will agree. This is the theme of Many-Minds Relativity MMR, which is a physical theory of relativity conforming to the 2019 SI Standard. 

Next question to be addressed: What will modern physics look like with SR replaced by MMR?

Of course some physicists will claim that SR is a theory about physics even after 2019, since it is a physical fact that the speed of light is the same for all observers independent of length scale adopted, even if that of course is absurd, and this is the reason it can be used as a meter standard. We may compare with time standard set by the same caesium clock for all observers with clock rate independent of inertial motion as a physical fact.  

 

  

New 2019 SI Meter Standard vs Special Relativity

The SI Standard adopted in 2019 specifies the speed of light c to be exactly 299792458 meter per second in all Euclidean coordinate systems, in particular in all inertial systems traveling with constant velocities with respect to each other. 

This means that in each coordinate system distance is determined by travel time of light signals assumed to travel at exactly the speed of c = 299792458 meter per second, with time measured by a standard caesium clock. 

The SI Standard thus requires all observers using different inertial systems to adjust their length unit so that the speed of light is the same for all observers. 

This means that with the 2019 SI Standard the basic postulate of Special Relativity SR of constancy of speed of light for all inertial observers is fulfilled as an agreement or standard, which cannot be subject to experimental verification since it is void of physics. 

This means that SR since 2019 is void pf physics, because the basic postulate of SR is simply an agreement and not a statement about physics which can be true or false. 

Already from the beginning in 1905 the physics of SR with its strange effects of time dilation, space contraction and relativistic mass, was subject to harsh criticism on very good grounds. But against all odds SR managed to survive under the cover of General Relativity GR, which was more difficult to question since it involved new mathematics no physicist could understand. 

So now we can finally put SR into the historic bin of non-physical theories including flogistons and luminiferous aether, and replace it by Many-Minds Relativity MMR which is perfectly compatible with the 2019 SI Standard. 

The central problem addressed in MMR is to what extent different observes using different inertial systems following the 2019 SI Standard, will agree. Take a look.  

Summary: With the 2019 SI Standard, SR is a non-physical theory, which as such is useless. MMR is a physical theory compatible with the 2019 SI  Standard addressing the problems which originally motivated SR. Since modern physics is based on SR viewed to be a physical theory, modern physics after 2019 is not the same as before. After a detour into SR over a period of 120 years, modern physics can now return to its rational classical foundation as Newton's mechanics and Maxwell's electromagnetics. 

Einstein Obsessed by the Speed of Light

Einstein founded his Special Theory of Relativity SR on two Postulates: 

1. The speed of light (denoted by c) is the same in all inertial systems.
2. Physical laws literally take the same form in all inertial systems.  

We have seen that since 2019 Postulate 1 is simply an agreement to define the length unit of meter in terms of the distance traveled by a light signal over a certain time interval, or equivalently an agreement to define the length unit of light-second as the distance traveled by light during 1 second. This is the new SI standard to be valid in all inertial coordinates system moving at different velocities. In other words, the unit of length in each coordinate system is simply adjusted so as to make the speed of light = c. 

The real question is to what extent different observers using different inertial systems, can agree. They agree on the speed of light but everything else is up to comparison.

Maybe this was understood by Einstein as an anticipation of the 2019 standard, or Einstein did not understand the difference between an agreement to use a certain standard as compared to actual physics not asking for any agreement as a physical fact. The fact that that the Sun rises every morning is not the result of an agreement but simply a physical fact.

In any case Einstein elevated the speed of light to have a fundamental significance. Einstein supported this idea by a claim that no physical effect can propagate faster than light (in vacuum), which gave light a special prominence in particular through the "equivalence of energy $E$ and mass $m$ mediated by  $E=mc^2$.  

But what is then the significance of the speed of light? Would the World be different if the speed of light was only half of current standard? Would the World be different if the speed of sound was only half of current estimate? What is the physical meaning of $E=mc^2$, if any at all?

It appears that Einstein in his 1905 patent office became obsessed with an idea that the speed of light $c$ has a universal significance, which he supported in "thought experiments" imagining himself riding on the crest of a light wave at the speed of light.  

We experience sound and light reaching our ears and eyes, but we rarely ask about the speed of sound or light, since it has no significance except as a nuisance in communication over large distances. 

Making something insignificant to something completely fundamental, will ruin any theory. Einstein was a master of such delusions. 

Einstein and the Crisis of Theoretical Physics

The crown jewels of modern theoretical physics are the electronic computer and the atomic bomb. In the light of these amazing achievements it is surprising that theoretical physics today is in a state of crisis because it does not deliver anything useful anymore, only increasingly wild speculations way beyond experimental verification. 

Modern theoretical physics is thus today in a state of confusion and it is natural to seek the origin of the confusion, in order to dismantle it and so return to rationality as the leading principle of classical physics. 

The departure form rationality was initiated by Einstein in 1905 with his Special Theory SR of starting from the following dictate (also called postulate): 

• The speed of light is (must be) the same for all observes moving with constant velocity with respect to each other, that is for all inertial observers.        

Einstein would have been pleased to find that his dictate was adopted by International System of Units (SI) in 2019 as a new definition of the length unit of meter as the distance traveled by light (in vacuum) during $\frac{1}{299792458}$ of a second, or what is the same: 

• The speed of light is exactly $299792458$ meter per second. 

We understand that a scientific standard such as the new SI meter standard, is an agreement made by scientists, like agreeing that there are 100 centimetres on a meter, which is to be compared with a scientific fact. The validity of a standard cannot be verified or disproved by a physical experiment: An experiment verifying that there are 100 centimeters on a meter, would not be possible to publish in a scientific journal. The referees would point out that such an experiment would be based on a misunderstanding of the relation between meter and centimeter. 

For the same reason, a new experiment showing that the speed of light is exactly $299792458$ meter per second would be met in the same way. It means that all observers are required to adjust their length scale to meet this standard, and the real question (answered in Many Minds Relativity) is to what extent different observers will be able to agree when using this standard. 

From his dictate about the speed of light, Einstein developed SR as a new form of relativistic mechanics with all sorts of new strange phenomena such as time dilation, space contraction, relativistic mass, fundamentally different from Newtonian Mechanics NM. 

NM was the ultimate expression of classical physics capturing all of mechanics including gravitation in the following precise mathematical terms as a Model of Newtonian Mechanics MNM:  

• $\rho=\Delta\phi$                                     (conservation of gravitational force)
• $\dot\rho +\nabla\cdot m =0$                        (conservation of mass)
• $\dot m +\nabla\cdot (um) +\rho\nabla\phi =0$    (conservation of momentum)

describing a (zero pressure for simplicity) distribution of matter subject to gravitation, where $\rho$ is mass density, $\phi$ gravitational potential, $\nabla\phi$ gravitational force per unit mass, $m$ is momentum, and $u=\frac{m}{\rho}$ is material velocity, all depending on a Euclidean spatial coordinate plus time with the dot representing differentiation with respect to time. MNM expresses the same physics in all inertial systems and so is a form of Galilean invariant relativistic mechanics perfectible compatible with the 2019 SI Standard of the meter. 

In MNM there is only one form of mass as inertial mass = passive gravitational mass = active gravitational mass, signified by the presence of $\rho$ in MNM.  

Today Einstein could have been perfectly happy with MNM as a relativistic universal mechanics with all observers agreeing on the same speed of light according to SI standard.

But that was not the situation in 1905 with physicists struggling to explain the null result of the Michelson-Morley experiment showing a speed of light independent of inertial motion in line with the SI standard, which was not yet made into an agreement and so seemed to require physics beyond NM. 

This is where Einstein stepped in by replacing NM by a new form of relativistic mechanics involving strange new effects of time dilation and space contraction as an explanation of the MM null result based on Lorentz transformation instead of Galilean transformation. Einstein thus dethroned Newton/Galileo to take the top position with SR, which brought him immense fame in a Faustian deal, which he admitted by asking for mercy: Newton, forgive me! 

But replacing NM by SR was a step away from rationality, because agreement/standard was being confused with physical fact and this has been carried into our time: If you ask a physicist of today if the speed of light of $299792458$ meter per second is a matter of definition/standard, you will get the response that it is also a physical fact: It is an agreement about physics, which is also a physical fact. It is like agreeing that 1+1 = 2 as a definition, while insisting that it is also a physical fact which you can subject to experimental verification and possible falsification.

While NM is rational and so understandable, SR is irrational and so not understandable. Modern theoretical physics is based on SR and so has to struggle with irrationality. This is the root cause of the crisis of modern physics: irrationality brought by Einstein.

More aspects of the irrationality of SR is given in Many Minds Relativity including aspects of NM in extreme situations with very large material speeds.  

SR was met by skepticism, which forced Einstein to lift the bet to General Relativity GR based on a postulate of inertial mass = gravitational mass automatically satisfied by NM, thus without substance. This added to Einstein's fame even if no Nobel Prize has been given to SR/GR because the Nobel Committee has remained skeptical for 100 years. 

The two pillars of classical physics are Newton's mechanics and Maxwell's electromagnetics describing the different physics of matter and light. Einstein claimed that Newton's mechanics is wrong, because it does not describe light, which lacked rationality.  

Summary: Modern physics was triggered by the null result of the MM experiment, which appeared to require new physics to explain why all inertial observers agree on the speed of light as a matter of physics. Einstein took on the challenge sitting at his desk as patent clerk performing "thought experiments" in support of SR starting from an assumption that all inertial observers agree on the speed of light thus simply assuming what was to be explained.  

PS: Recall that Einstein based SR on the following two postulates

1. The speed of light is the same for all inertial systems.
2. Physical laws take the same form in all inertial systems.  

We understand that today 1 is an agreement and so not a statement about physics, nor does 2 contain any actual physics. It means that SR, as being based on postulates without real physics, does not say anything about real physics. This is clearly understood by any physicist with classical training in rational thinking, but not by modern physicists confused by irrational thinking.

Objective of Quantum Mechanics to Predict Outcomes of Experiments?

Leading modern theoretical physicists can tell you:

• The objective of quantum mechanics is to predict outcomes of (quantum mechanical) experiments. 

You may find this a bit strange. Isn't the objective of theoretical physics to understand physical processes. In the case of quantum mechanics, that would be to understand the microscopic physics of atoms, electrons, protons, neutrons and more. But this is not possible in the case of quantum mechanics, since in the words of Richard Feynman:

• Nobody understands quantum mechanics.

So what is left is the to predict outcomes of experiments, which seems a bit like betting on a horse race. Or is the theoretical physicist simply mocking with you, to avoid further questions?

Ok, if the experiment agrees with the prediction, then you may view that as support to an idea that the theory is correct, in that specific case. But to confirm a theory by experiments requires massive experiments. It is not enough, in general, to make just one experiment and then say that the theory is correct. Maybe that experiment was very special? 

In any case this practised a lot: To confirm Einstein's General Theory of Relativity GR, it was enough with one observation of a very slight change of the apparent position of a star during the solar eclipse on May 29 in 1919 (the perihelion shift of Mercury was not a prediction). For a second confirmation, we had to wait until the LIGO gravitational wave detection at 09.51 UTC on 14 September 2015 of two ~30 solar mass black holes merging about 1.3 billion light-years from Earth. But that was also a very special case. In any case, GR is now considered to be fully confirmed by two very special/extreme (and questionable) observations. 

Similarly, the Standard Model of fundamental physics is supposed to now be fully confirmed by very special experiments at LHC completed in 2012 showing existence of the Higgs boson after a 40 year long fruitless search, as a little jump on an energy graph. 

But if the experiment does not agree with theoretical prediction, what to do? Throw the theory away because it fails on one experiment? Maybe quite reasonable if the experiment is relevant. The alternative is to modify the theory by e g some new parameter to agree with the experiment, but then the prediction aspect is missing. Of course it is also possible to modify the experiment until agreement with theory, but again without true prediction.

To fully confirm a general theory by experiments is impossible. To confirm a general theory by very special experiments, as seems to be the current standard, is not very convincing to me. 

Newton's theory of gravitation is a general theory, which is supported by a generality of  experiments/observations and contradicted by none, and can be understood from conservation principles. It can serve as the role model for all of theoretical physics.

 

If the element of understanding is missing, then theoretical science seems to reduce to fitting theory to experiment or vice versa. Is this the reason for the current crisis of fundamental physics? 

What then about GR? Again, we have a theory which is very difficult to understand. Einstein said he could not understand it, but how is it possible to formulate a theory without understanding it? Of course a modern physicists would proudly say that there are two main theories of modern physics, quantum mechanics and GR (which happen to be contradictory/incompatible), and then act as if he/she understand these theories quite well, if not in full detail, while showing no willingness to go into a discussion about specifics of the theories and referring instead to the very rich literature explaining GR written by people who really understand GR.  

It means that a modern theoretical physicist will have to struggle with general theories, which cannot be understood nor confirmed by experiments, since only very special experiments are available, if any at all.

At the same time the modern theoretical physicist must give the impression of understanding and presence of confirmation.