star forming near center of our galaxy

http://physicsworld.com/cws/article/...ky-ways-centre

I have always been of the opinion that stars are in fact spit out by the (rotating) black hole,
and spiral arms are formed that way.
This seems to point to such a process and supports it.

On Friday, March 20, 2015 at 6:07:44 AM UTC-4, Jan Panteltje wrote:
http://physicsworld.com/cws/article/...ky-ways-centre

I have always been of the opinion that stars are in fact spit out by the (rotating) black hole,
and spiral arms are formed that way.
This seems to point to such a process and supports it.

Not really. That article presented evidence of star formation from gas clouds, not whole stars ejected from a black hole. Also, the orbits of stars around Sgr A* have been measured and they are pretty normal Keplerian ellipses, not stars on escape trajectories.

On a sunny day (Tue, 24 Mar 2015 12:25:57 -0700 (PDT)) it happened Craig
Markwardt wrote in
:

On Friday, March 20, 2015 at 6:07:44 AM UTC-4, Jan Panteltje wrote:
http://physicsworld.com/cws/article/...ky-ways-centre

I have always been of the opinion that stars are in fact spit out by the (rotating) black hole,
and spiral arms are formed that way.
This seems to point to such a process and supports it.

Not really. That article presented evidence of star formation from gas clouds,

Right.


not whole stars ejected from a black hole.

If 'black holes' exist or not, apart from the purely theoretical fact
that nothing can escape when escape velocity is greater than C,
the 'inner part' of galaxies often looks like a bar, where the ends leave a trace of stars
while it (the bar) rotates, that trace being the spiral arms.
I think the processes at the center of a galaxy (this galaxy) are far more complicated
than just 'black hole'.



Also, the orbits of stars =
around Sgr A* have been measured and they are pretty normal Keplerian ellipses,

It is funny, as observations of the orbits of stars in galaxies has shown that those are indeed not 'in orbit'
as in the sense of Newtonian orbit, and that caused people to come up with MOND,
dark matter, and what not.

In my view if the orbits do not obey Newton's law, then (Occam's razor) then they are NOT in orbit.

Bit silly to say well lets modify the math a bit,
well you can probably write any polynomial to closely match anything, but that has nothing to do with understanding.



not stars on escape trajectories.

I did not claim that.

Look at it (the galaxy) as a garden sprinkler,
the process in the center (high pressure hose feeding in that case) plus centrifugal force
causes water droplets to be ejected,
those droplets are _not_ in some orbit.

The interesting thing is when you look at the ends of the spiral arms, where do the stars go?
Well they do not go anywhere, it is their end position likely (maybe held back by intergalactic space, who knows).


Science has so often got it the wrong way around, in history, earth could not be round,
people would fall of in Australia etc...

Celestial mechanics anything you see.

Look at some simple fireworks, make your own galaxies, it all originates from the center.

On Wednesday, March 25, 2015 at 5:00:34 AM UTC-4, Jan Panteltje wrote:

not whole stars ejected from a black hole.

If 'black holes' exist or not, apart from the purely theoretical fact
that nothing can escape when escape velocity is greater than C,
the 'inner part' of galaxies often looks like a bar, where the ends leave a trace of stars
while it (the bar) rotates, that trace being the spiral arms.
I think the processes at the center of a galaxy (this galaxy) are far more complicated
than just 'black hole'.

I think that's quite true, but I also don't think you will find anybody in astronomy who claims that galactic dynamics are "just black hole."

You claimed that the paper supported your idea that stars were being "spit out" by a black hole. But in fact the paper showed that what was happening was star formation from gas, not stars being spit out.


Also, the orbits of stars =
around Sgr A* have been measured and they are pretty normal Keplerian ellipses,

It is funny, as observations of the orbits of stars in galaxies has shown that those are indeed not 'in orbit'
as in the sense of Newtonian orbit, and that caused people to come up with MOND,
dark matter, and what not.

Please don't confuse the issue. The stars in orbit within a few hundred AU of Sgr A* are dominated by the gravity of a single compact (but invisible object). This is evident because the detailed orbits of individual stars can be measured, and they are consistent with a central point mass of ~4 million solar masses. And they are closed, non-escaping, elliptical orbits. No sprinkler hose.

The issue of the stellar dynamics for populations far from the center is a different matter. At those distances, a 4 million solar mass central object is negligible compared to the amount of stellar material, gas material and dust material enclosed within the orbit. There something else is going on.

On a sunny day (Mon, 30 Mar 2015 17:28:54 -0700 (PDT)) it happened Craig
Markwardt wrote in
:

On Wednesday, March 25, 2015 at 5:00:34 AM UTC-4, Jan Panteltje wrote:

not whole stars ejected from a black hole.

If 'black holes' exist or not, apart from the purely theoretical fact
that nothing can escape when escape velocity is greater than C,
the 'inner part' of galaxies often looks like a bar, where the ends leave=
a trace of stars
while it (the bar) rotates, that trace being the spiral arms.
I think the processes at the center of a galaxy (this galaxy) are far mo=
re complicated
than just 'black hole'.

I think that's quite true, but I also don't think you will find anybody in =
astronomy who claims that galactic dynamics are "just black hole."

You claimed that the paper supported your idea that stars were being "spit =
out" by a black hole. But in fact the paper showed that what was happening=
was star formation from gas, not stars being spit out.


Also, the orbits of stars =
around Sgr A* have been measured and they are pretty normal Keplerian el=
lipses,

It is funny, as observations of the orbits of stars in galaxies has shown=
that those are indeed not 'in orbit'
as in the sense of Newtonian orbit, and that caused people to come up wit=
h MOND,
dark matter, and what not.

Please don't confuse the issue. The stars in orbit within a few hundred AU=
of Sgr A* are dominated by the gravity of a single compact (but invisible =
object). This is evident because the detailed orbits of individual stars c=
an be measured, and they are consistent with a central point mass of ~4 mil=
lion solar masses. And they are closed, non-escaping, elliptical orbits. =
No sprinkler hose.

The issue of the stellar dynamics for populations far from the center is a =
different matter. At those distances, a 4 million solar mass central objec=
t is negligible compared to the amount of stellar material, gas material an=
d dust material enclosed within the orbit. There something else is going o=
n.


In my view if the orbits do not obey Newton's law, then (Occam's razor) t=
hen they are NOT in orbit.

That's a pretty good view, but it presupposes the amount of mass. As a ref=
resher, Kepler's laws (not Newton's) depend on how much mass is enclosed by=
the orbit. For galactic rotation curves the whole game is determining the=
mass by estimating it from the amount of starlight. Galactic rotation cur=
ves completely obey Kepler's and Newton's laws of motion, as long as additi=
onal non-visible matter is assumed.

But this is not a crazy assumption since non-visible (dark) matter is found=
on many scales, not just intragalactic. The orbit of M31 requires dark ma=
tter. The gravitational potentials of clusters of galaxies require dark ma=
tter (via X-ray emission). Gravitational lensing requires dark matter. Et=
c.

There are some other games in town, for example modified gravity (MOG) does=
not required dark matter. But this is at the expense of a more convoluted=
theory of gravity, which has its own adjustable parameters and is arguably=
less elegant.

OK,
they say a picture is a thousand words:
http://photojournal.jpl.nasa.gov/jpeg/PIA16613.jpg
http://www.space.com/25584-milky-way...iral-arms.html


Note the bar like structure at the center,
and how star formation is most intense there,
and how it 'fades out' at the end of the spiral arms.
Clearly the bar like structure is rotating.

I have seen pictures of galaxies where the rotation of the center bar changed direction,
and so did the spit out spiral arms.
So then you had 2 sets of spiral arms, one in each direction.

I could imagine the stars at the outer edge of the spiral arms to cool down and become some 'dark stuff',
dark in the sense of difficult to observe, not some exotic sort of matter.
Not that that should not exists, but where does the spit out stuff go?

On Friday, April 3, 2015 at 5:54:07 AM UTC-4, Jan Panteltje wrote:

OK,
they say a picture is a thousand words:
http://photojournal.jpl.nasa.gov/jpeg/PIA16613.jpg
http://www.space.com/25584-milky-way...iral-arms.html


Note the bar like structure at the center,
and how star formation is most intense there,
and how it 'fades out' at the end of the spiral arms.
Clearly the bar like structure is rotating.

I'm not sure why you picked a disturbed galaxy that has huge tidal tails, but you did. That is not a typical example of a spiral.

I don't believe that the galactic dynamics of spiral formation and bar formation are completely settled, but they do not require stars being "spit out" by a central black hole. Rather, it is more like a traveling wave pattern, and/or standing wave.

CM

Hi Craig
long time no see.
I notice a new analysis of frb data (Hippke,Learned)seems to suggest the arrival times of higher frequency radiation
from gammaraybursts arrives sooner than longer wavelengths. And there is a distance/wavelength
relationship based on multiples.
Way back in early 2000,s I had said to you that arrival times of longer wavelengths in grb data
are such that arrival times of wavelengths for longer wavelengths would be in multiples
....So that an arrival time for 2nm at would if seen 100 seconds later for 200 nm if
It was observed to arrive at 10 seconds for 20 nanometers.
I seem to remember you explicitly arguing many years ago that this
wasnt possible.
It seems to me that this latest data interpretation confirms my prediction
and rules out your objection that my analysis is incorrect.
Any thoughts on this?

On Thursday, April 9, 2015 at 10:36:57 AM UTC-4, jay moseley wrote:
Hi Craig
long time no see.
I notice a new analysis of frb data (Hippke,Learned)seems to suggest the arrival times of higher frequency radiation
from gammaraybursts arrives sooner than longer wavelengths. .
....
Any thoughts on this?

What do fast radio bursts (FRBs) of the Hippke Learned et al, have to do with Gamma ray bursts (GRBs)?

On Tuesday, 31 March 2015 01:28:57 UTC+1, Craig Markwardt wrote:
On Wednesday, March 25, 2015 at 5:00:34 AM UTC-4, Jan Panteltje wrote:

not whole stars ejected from a black hole.

If 'black holes' exist or not, apart from the purely theoretical fact
that nothing can escape when escape velocity is greater than C,
the 'inner part' of galaxies often looks like a bar, where the ends leave a trace of stars
while it (the bar) rotates, that trace being the spiral arms.
I think the processes at the center of a galaxy (this galaxy) are far more complicated
than just 'black hole'.

I think that's quite true, but I also don't think you will find anybody in astronomy who claims that galactic dynamics are "just black hole."

You claimed that the paper supported your idea that stars were being "spit out" by a black hole. But in fact the paper showed that what was happening was star formation from gas, not stars being spit out.


Also, the orbits of stars =
around Sgr A* have been measured and they are pretty normal Keplerian ellipses,

It is funny, as observations of the orbits of stars in galaxies has shown that those are indeed not 'in orbit'
as in the sense of Newtonian orbit, and that caused people to come up with MOND,
dark matter, and what not.

Please don't confuse the issue. The stars in orbit within a few hundred AU of Sgr A* are dominated by the gravity of a single compact (but invisible object). This is evident because the detailed orbits of individual stars can be measured, and they are consistent with a central point mass of ~4 million solar masses. And they are closed, non-escaping, elliptical orbits. No sprinkler hose.

Its absurd to suggest that just because you cant do an n3 body calculation
for all the stars/mass in the central halo (assuming no central BH). That
somehow this can only mean that the only correct calculation is a keplerian
one assuming a centrally located (Black hole) mass. That's not logical.
Not being able to do a calculation does not invalidate its potential
conclusion.
I have seen simulations of n body calculations where n3 and although crude
in their limitations they do show orbits near the center that appear elliptical.

On a sunny day (Fri, 10 Apr 2015 06:06:47 -0700 (PDT)) it happened jay moseley
wrote in

as in the sense of Newtonian orbit, and that caused people to come up w=
ith MOND,
dark matter, and what not.

Please don't confuse the issue. The stars in orbit within a few hundred =
AU of Sgr A* are dominated by the gravity of a single compact (but invisib=
le object). This is evident because the detailed orbits of individual sta=
rs can be measured, and they are consistent with a central point mass of ~=
4 million solar masses. And they are closed, non-escaping, elliptical orb=
its. No sprinkler hose.

Its absurd to suggest that just because you cant do an n3 body calculation
for all the stars/mass in the central halo (assuming no central BH). That
somehow this can only mean that the only correct calculation is a keplerian=

one assuming a centrally located (Black hole) mass. That's not logical.
Not being able to do a calculation does not invalidate its potential
conclusion.
I have seen simulations of n body calculations where n3 and although crude
in their limitations they do show orbits near the center that appear ellipt=
ical.

If you squeeze an orange or grape fruit the fluid will spit out of the sides.
If it spits out even a bit asymmetrical then the orange should start rotating in free space.
Black hole, an other mathemagical solution to everything.
It is simply not that simple.
And, BTW
Panteltje's rule 1: There are no infinities in nature, something will always give way.
Panteltje's rule 2: We will NEVER be able to comprehend EVERYTHING (nor a theory thereof)
just like an ant cannot understand the motivation of the architect who designed the wall it is creeping up.
Not enough neurons, you CANNOT grab 'Everything' in a limited amount of 'memory' or 'hardware'
or 'neurons' or whatever you use or identify yourself with.
Now I can live with these 2 rules, and as soon as somebody knows 'everything' I'm out of here :-)

Jan Panteltje
Weapons of Math Destruction.


Man not done so much philosophy in ages, just moved teh grass, cleaned teh house, did the shopping,
and ate a chocolate bar.
I am pretty sure that was real, I really changed the structure of the entire universe,
or ?? rather it moved and I obeyed.
We are but puppets, no free will or Free Willy or whatever.
But, God willing??? Willy will be freed.
i am not religious BTW.
see it this way:
Stars get born, die, explode and here I am, and have to surrender.

mm how about a big bang tax, things will cool of ye know, maybe taxing (of course) will stop that.
What's the word: ??
**** cannot remember.
Ha, 'entropy', I cheated:
http://en.wikipedia.org/wiki/Heat_death_of_the_universe
Intersting view no?