@Z

Micro black holes have probably fizzled by now. 

But intermediate primordial black holes still exist and contribute to the galactic halo

https://www.researchgate.net/publication/269689929_Advances_in_Black_Hole_Physics_and_Dark_Matter_Modelling_of_the_Galactic_Halo

Article Advances in Black Hole Physics and Dark Matter Modelling of ...

Dear Prof. Motyka,

                                 In terms of our research into "low dimensional physics" with "genetic quality" "Arrow of Time" Quantum Mechanical Localised General Relativistic Physics of say Stock Markets there can be instances of Market Crashes (zero entropy) triggered by the zero potential of information stocks (one can think of these as zeros with information reservoir potentials (Mallick (2016) referred on RG website by courtesy Prof. E.Tjaland and NTNU) Dynamic Equilibrium homologous and isotropic to instanton condensation of String Theory Black Hole Physics (Witten, Sen, Arkani Hamid and others, also in our work with reservoir potentials and engineering using D-Branes String Systems and in spacextime relativistic factorisation)  hence null flows but with null closure of the Tychonoff product Groups generated by spacextime interactions. with meta information distributed ensembles In Econophysics of Stock Markets. This equilibrium can be sustained because of zero entropy requirements of stock market equilibrium with no spin polarisation associated with such equilibrium as derived above. Hence BH and mBH can be identical group closure limits under such resolution of space time and event horizons with approximately uniform (classical) gravity. I hope that at least serves as a mind experiment to your question and the discussions.

SKM, NH, SM

Dear Prof. Motyka and all the Distinguished persons following this String, 

                  We may someday discover/invent solar optics which may allow us to coat the earth's surface with extra layers of gravitons as a smooth virtual orbifold meanfield of instantons and tachyons, but it's hard to predict what the earth would look like being a lens! But we think Einstein's Relativity Principle will get a new meaning for something very low dimensional in infinite space viz. that of some harmonic oscillator which brings dynamism into our stock markets.

SKM, NH, SM

Dear Prof. Motyka,

                                We read the very interesting String on Strategic Orientation and I am glad to report that by building in the postulates of "Genetic Quality Orientation" and "Arrow of Time" in Stock Markets or wealth markets one of us has been working with since 1988 , please refer to Soumitra K. Mallick's RG website, it has been found that if you consider the process of optimal growth which are based on steady state genetic felicity models with consumption-investment actions fundamental particle (money or relativistic energy) spacextime interaction picture in classical-quantum Tychonoff closure product algebra meanfields at normal room temperature and pressure of every country standard, and can find the what has been identified as Dbranes String Capital Stocks and Flows in Stock Market meanfields, which exists in Indian Emerging Market and U.S. and other developed market data experiments (Sokoloff & Sokoloff (Econometrica (2012 ?)), one can detect these Lagrangean and String condensed Hamiltonian Control paths of what has been referred to as "strategic orientation" (without trying to stretch my imagination too far perhaps, event horizon by suitable factorization of the Physical  Chemical Technology Computer Network String-Dbranes dual (developed mainly by my son Sandipan Mallick with group closure limits which can be further factorised by our Classical-Quantum Laws of Econophysics. You can refer to our P Vs. NP paper on the website. Also please refer to the coal mining paper on the website. We are working on this and discovered Tachyon condensed limiting Fields but do not know whether this leads to M theory.

SKM, NH, SM

Micro-black holes of mass less than about 10^{14}  gm would have all evaporated away by now due to Hawking radiation if they were created before decoupling of matter and radiation (i.e. when the universe was only 380000 yrs old). Hence, only micro-black holes with mass greater than about 10^{18} gm can constitute dark matter. But there are severe constraints on their abundances resulting from observed diffused background radiation. See B. Carr's papers on this topic. 

Primordial black holes may constitute a part of dark matter if it's mass is in the range between 20 and 100 solar masses. Therefore when LIGO  has observed a binary black hole system merger and when each of them has a mass of about 30 solar masses, it could be possible that LIGO has actually observed dark matter. Such a possibility has been considered in a recent article in Phys. Rev. Letters. authored by S. Bird et. al. Phys. Rev. Lett. 116, 201301 (2016); https://arxiv.org/abs/1603.00464

Dear Zbigniew!

In my opinion the idea of "black holes" is only a formalism based on theories which based on assumptions which based on ... and so on.

The existence of "Black holes" would mean that sooner or later all the matter in universe would be captured by this theoretical objects. Rather in case of a high concentration of material matter (like in the centre of galaxies) it will take place processes of destruction. Sometimes we can observe gigantic bursts of energy in the depths of the universe and indirect also in our galaxy. In our galaxy it was the last time about 65 millions years ago.

In universe exists a gigantic cycle of material-energetical conversion. There was no beginning and there will be no end.

Even the human comprehension is subject to constant change. Today we chuckle at some of the ideas hundred years ago and you can be sure that the people will do the same at many current ideas and theories in a hundred years.

My Regards!

Hans