Physics is Dying

Theoretical physicist Sabine Hossenfelder is angry. Sabine is finished with modern physics: This is why physics is dying: 20 years without progress:

• We are endlessly arguing about irrelevant questions.
• This is why physics is dying.
• Loop Quantum Gravity and String Theory cannot be tested.
• Same thing with Supersymmetry and Inflation and Dark Sectors. 
• I do not understand why people get paid for this. 
• Research bubbles of mathematical fiction without connection to reality.
• I cannot believe that this is still going on.
• We are seeing the beginning of a collapse of the foundations of physics.
• These people sit on cosy tax paid positions with no other task than producing useless papers.

This is also my impression.

But what do you do when you understand the theory, which is the very foundation of your academic position, does not work? If you do not see a new theory that you could jump to? Is this what is frustrating Sabine so very much?

A scientific theory is like an Empire and Empires do not fall without much fight and anger. 

Mass: Inertial = Passive Gravitational = Active Gravitational

Maybe, it is now time for Newton to return? Maybe I was wrong? In any case: Newton forgive me!

The basic model of Neo-Newtonian Cosmology takes the following form in terms of gravitational potential $\phi$ as primordial, mass density $\rho$, momentum $m$ and $u=\frac{m}{\rho}$ material velocity all depending on a Euclidean space coordinate $x$ and time coordinate $t$ with the dot on top representing differentiation with respect to time:

• $\rho = \Delta\phi$                                    (inverse square law in differential form)
• $\dot\rho +\nabla\cdot m=0$                       (conservation of mass)
• $\dot m +\nabla\cdot (um)+\rho\nabla\phi=0$    (conservation of momentum: Newton's 2nd Law)  

A basic property of this model is conservation of energy in the sense that total energy $KE + GE$  with $KE$ total kinetic energy and $GE$ total gravitational energy, does not change over time: 

• $\frac{d}{dt}(KE+GE) = 0$        (conservation of total energy)

with 

• $KE = \int \rho\frac{u^2}{2} dx$
• $GE = -\frac{1}{2}\int\vert\nabla\phi\vert^2dx$. 

In this model we have identified 

• inertial mass = passive gravitational mass                        (Galileo's Equivalence Principle EP)
• passive gravitational mass = active gravitational mass     (Newton's EP)

with 

• inertial mass = mass $\rho$ in $\rho\frac{u^2}{2}$
• passive gravitational mass = mass $\rho$ in $\rho\nabla\phi$
• active gravitational mass = mass $\rho$ in $\Delta\phi =\rho$. 

In other words, the model has only one form of mass appearing in three different contexts with equality expressed as Galileo's EP and Newton's EP as fundamental features of Newtonian mechanics in the form of Neo-Newtonian Cosmology.

We recall that Einstein used Galileo's EP as a Postulate for his General Relativity (probably also with less exposure Newton's EP). 

Leibniz' Principle of Sufficient Reason shows that Galileo's EP (universality of free fall) cannot be false since sufficient reason is lacking, while violation of Newton's EP would violate conservation of total energy. 

Conclusion1: The basic model of Neo-Newtonian is simple, universal and computable, and must be fundamentally correct. There is no sufficient reason to replace it by General Relativity, which is the opposite of both simple and computable. Recall that a main dilemma of modern physics is the apparent incompatibility/contradiction between Einstein's relativity and Schrödinger's quantum mechanics, while Newton and Schrödinger are fully compatible.

Conclusion2: Kinetic energy KE can increase from decreasing GE from increasing $\vert\nabla\phi\vert^2$ from concentration of mass as the engine of gravitational collapse, which gives an endless source of kinetic energy. 

Question: Neo-Newtonian Cosmology and Einstein's Cosmology/General Relativity both start from Galileo's EP + Newton's EP. Does it mean that Einstein agrees with Newton? Probably not, since the basic idea of modern physics is that Einstein does not. The difference appears to be that Einstein demands Lorentz invariance as his incarnation of a Principle of Relativity, while Newton is happy with Galilean invariance. So we have Einstein-Lorentz against Newton-Galileo. What is your bet? Newton-Galileo reigned from 1600 to 1955, while Einstein-Lorentz took over in the 1970s along with the decline of modern physics into our days. Time for Renaissance of Newton-Galileo?

PS1 Recall that the Lorentz transformation lacks physical meaning and so must Lorentz invariance, while Galilean invariance expresses real Newtonian physics. 

PS2 Recall that the the above model naturally suggests low intensity distributed $\rho =\Delta\phi\ge 0$ as dark matter and naturally extends to $\rho =\Delta\phi$ of variable sign as origin of dark energy.

Gravitational Mass of Visible Matter vs Invisible/Dark Matter

The previous post (on Neo-Newtonian Cosmology NNC) about dark matter asks if invisible/dark matter connected to a primordial gravitational potential  $\phi$ through the Laplacian differential operator $\Delta$, may not react to gravitational force $-\nabla\phi$ in the same way as visible matter, maybe not at all. 

The halo of invisible/darl matter supposedly surrounding a galaxy would then contribute to gravitational force as an explanation of observed rotation, but would not itself be subject to contraction by gravitational force. 

There would thus be a fundamental difference between visible and invisible/dark matter beyond visibility: Visible matter has gravitational mass (equal to inertial mass), while invisible/dark matter has zero gravitational mass thus acting as a passive contributor to gravitational potential without feedback from gravitational force.

(This is sometimes referred to as active and passive gravitational mass, with the meaning of active and passive switched from a perspective that mass is primordial.) 

There would thus be fundamental difference between the galaxy and the surrounding halo depending on the nature of $\Delta\phi$ as high-density-localised visible or as low-density-distributed invisible.   

The current paradigm of Big Bang + Inflation as Post-Newtonian Cosmology suffers from basic questions without answers such as: What was before Big Bang? What was driving initial very rapid Inflation?

Neo-Newtonian Cosmology offers answers to these questions, and more. Maybe it is time for Newton to come after having been replaced by Einstein during 100 years of confusion.

Cosmology is troubled by the apparent impossibility of detecting any particle nature of dark matter. The basic idea of modern fundamental physics is that of particles as some form of point-like little things which can be captured in particle accelerator detectors, but no dark matter particles have been found, not even by the giant particle detector at LHC (see human scale bottom): 

        Dark matter cannot be detected in a particle accelerator, because it is a large scale phenomena.  

Visible Matter vs Invisible/Dark Matter

The apparent gravitational presence of invisible/dark matter is a key open problem of modern cosmology. 

Recent posts seek an answer as Neo-Newtonian Cosmology NNC starting with a primordial gravitational potential $\phi$ as a rapidly oscillating small amplitude perturbation of a zero potential from which mass density 

• $\rho\equiv\Delta\phi\ge 0$ 

is created through the action of the Laplacian differential operator $\Delta$ acting in a Euclidean infinite space. 

We assume a decomposition $\rho =\rho_v +\rho_{iv}$ with $\rho_v$ as substantial and localised representing visible matter, and $\rho_{iv}$ as small and distributed representing invisible/dark matter with clear separation. With $u=u_v+u_{iv}$ as total matter velocity decomposed into velocity $u_v$ of visible matter and $u_{iv}$ that of invisible dark matter, NNC takes the following concise form:

1. $\rho_v+\rho_{iv} = \Delta\phi$                           (inverse square gravitational law in differential form)
2. $\dot\rho_v =-\nabla\cdot (\rho_v u_v)$                   (conservation of visible matter)
3. $\dot\rho_{iv} =-\nabla\cdot (\rho_{iv} u_{iv})$                 (conservation of invisible/dark matter)
4. $\dot u_v=-\nabla\phi$                                    (Newton's 2nd Law for visible matter) 
5. $\dot u_{iv}=-\nabla\phi$                                  (Newton's 2nd Law for invisible/dark matter) 

We see that the total gravitational force $-\nabla\phi$ acts on both visible matter and invisible/dark matter in qualitatively different ways, with precise motion of visible matter as high density + localised and imprecise motion of invisible/dark matter as low density + distributed. 

The observed velocity distribution of visible matter of spiral galaxies can now be understood as driven by gravitational force from $\nabla\phi$ resulting from presence of high density localised visible matter together with presence of  low density distributed invisible/dark matter.

The key assumption is that visible matter as high density localised in the form of protons and electrons carries electromagnetics, while invisible/dark matter as low density distributed of unknown form, does not. 

Here high density localised represents stars and galaxies separated by large apparent voids, while low density distributed may represent a large halo around a galaxy, see below. 

It is natural to extend to dark energy as $\Delta\phi <0$ as small + distributed with an effect of anti-gravity or repulsion between matter of different sign (and attraction for same sign).

NNC naturally explains an expanding Universe from repulsion between matter of different sign.

Questions: 

• Why does the dark matter halo not gravitationally contract? Is the density too small? Is the rate of contraction very small? Is it possible that the invisible/dark matter does not react to gravitational force, only contributes to gravitational potential? 
• Is the visible galaxy formed from a primordial halo by gravitational contraction of in its center into visible matter?