Re: Evidence for EXTERNAL Galaxy black holes.

On Jan 28, 7:24 am, "LeoV...@xxxxxxxxx" <LeoV...@xxxxxxxxx> wrote:
Evidence for EXTERNAL Galaxy black holes.
It is well established that X-ray production should be present around
black-hole sources due to interaction with local gas.

Your unstated assumption is that the mass accretion rate is high, i.e.
the local interstellar medium must be dense and infalling. In fact,
the mass accretion rate is not always high.

As a consequence we should observe black hole locations around gaseous
galaxies in space by x-ray images taken by the CHANDRA satellite.

Given your oversight noted above, we should not *necessarily* observe
central black holes in every galaxy.

Andromeda, (M31) and the Sombrero galaxy (M104) seem to be excellent
examples. .
However in both cases the brightest x-ray sources are located FAR
OUTSIDE these galaxies.
This seems to be a clear support for a NEW black hole theory able to
explain such black hole anomalous behaviour.

Or, evidence that sometimes the mass accretion rate of black holes is
low instead of high.

Consider the Milky Way galaxy. There are many intermediate mass black
hole candidates in our galaxy, located in random X-ray binaries, and
not located at the center. Most are episodic accretors.

That fact does not *also* preclude the knowledge that there is a super-
massive black hole at the galactic center, called Sgr A*. This fact
is based on direct measurement of the orbits of many stars orbiting
the central massive object, and determines the central mass with
exquisite precision. However, the Sgr A* object itself is
'dark' (actually it is faintly luminous in X-rays). There is a
separately line of evidence, based on time-delayed light echos from
gas clouds near the galactic center, that Sgr A* was active several
tens of thousands of years ago. All of the evidence that I am aware
of points to a situation where black holes mostly accrete and emit
episodically, not continously.

Thus, there's doesn't seem to be a need for a new theory of black
holes.

CM
.

Relevant Pages

  • Re: Evidence for EXTERNAL Galaxy black holes.
    ... It is well established that X-ray production should be present around ... Your unstated assumption is that the mass accretion rate is high, ... evidence that sometimes the mass accretion rate of black holes is ... massive black hole at the galactic center, called Sgr A*. ...
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