Monday, February 20, 2006

RIT Professor Releases New Study About How Black Holes Can Kick Each Other Out Of Merging Galaxies


By Elaine Meinel Supkis

Yet another study of what is now known to be a very common event: galaxies colliding with each other. This latest paper by Prof. Merritt is tries to explain why smaller galaxies sometimes don't have a black hole core anymore. At the same time this work has been done, astronomers in Britain claim they have located a major galactic black hole split event at HE0450-2958. There is some dispute about this.

From Eurekalert.org:
Virtually all galaxies are believed to contain supermassive black holes at their centers. According to current theory, galaxies grow through mergers with other galaxies. When two galaxies merge, their central black holes form a binary system and revolve around each other, eventually coalescing into a single black hole. The coalescence is driven by the emission of gravitational radiation, as predicted by Einstein's theory of relativity.

Merritt and his colleagues determined how fast a black hole has to move to completely escape a galaxy's gravitational field. They found that larger and brighter galaxies have stronger gravitational fields and would require a bigger kick to eject a black hole than the smaller systems. Likewise, less forceful impacts could jar the black hole out of its home at the center of a galaxy, only to later rebound back into position.

The kicks also call into question theories that would grow supermassive black holes from hierarchical mergers of smaller black holes, starting in the early universe. "The reason is that galaxies were smaller long ago, and the kicks would easily have removed the black holes from them," Merritt says.

According to Merritt and his co-authors, it's more likely that supermassive black holes attained most of their mass through the accretion of gas and that mergers with other black holes only took place after the galaxies had reached roughly their current sizes.
Right on the heels of this paper being published came this news out of Europe. From World Science:
A collision between two galaxies may have led them to spit out a colossal black hole that’s still soaring through space, some astronomers have calculated.

If correct, the proposal would be the first evidence of a possibility astrophysicists have theorized for years: a black hole’s expulsion from a galaxy.

Indirectly, it could also shed light on how some black holes became as big as they are—a longstanding puzzle that’s also entangled with the question of how galaxies formed.

A team of researchers describe the results in a paper to appear in an upcoming issue of the Monthly Notices of the Royal Astronomical Society, a research journal.

They claim an enigmatic object known as HE0450-2958, estimated to weigh as much as 400 million suns or more, may be the expelled black hole.
I have noticed some people have mocked Europe for "weakening" and becoming a "backwater" for science. This comes mostly from Americans who like to preen themselves for our past accomplishments all of which have been in rising jeopardy thanks to the insane Bush/GOP program to dumb down America.

Prof. Merritt disputes the contention of the Europeans saying, the black hole is still inside the hot gas envelope of the host galaxy so it really hasn't "escaped". I contend, it can't escape. Indeed, no galaxy will ever escape any other, bigger, galaxy's gravitational pool because contrary to present dogma, the universe isn't expanding straight outwards, time/space isn't straight at all, it is increasingly warped as we move further away from the initial impetus of the Big Bang's outward force.

Here is the picture of one black hole spiralling away from its host.

When I was a child, Walt Disney used to produce "science" films and cartoons. One of them was about the space program and tried to explain gravity and how rockets don't fly straight away from the earth but have to spiral away. My parents were asked to view the film before it appeared in public to critique it. Since our family had seven children, we were asked to watch, too. I remember vividly the parts where they illustrated physics by using billiard balls and a cue stick. After the showing, we demanded our father get us a pool table and we played it so much, I used to amuse myself as an adult, knocking those ivories about in bars, astonishing men who thought women couldn't play well.

The main thing was, using the billiard table model gives a totally false mental picture of the cosmos. For it isn't flat. Carl Sagan gave a much better presentation explaining gravity on his famous TV series for PBS. He understood, the critical nature of time/space around any physical body is warped and the only way most items operate in this medium is to spiral in or out. Indeed, comets and rockets skim down into gravitational pools in order to pick up speed as they skim back out again. It seems as if they then fly off, forever, except they don't, for the most part. Most of the rocks that fall down the sun's gravitational pool shoot back into deep space only to return. This was first noted about Halley's comet, a recent spectacular visitor who comes back like clockwork, it being trapped in the inner la Grange orbits of the sun.

Rocks trapped on the sun's galatic plane seldom degrade in orbit. But those which fall down the pool from other angles do degrade and they are a tremendous danger to us since they can hit the planets that orbit the sun. One should suppose, the angle of movement determines whether or not a body "merges" (crashes).

Back to billiards and black holes: it seems pretty certain, the universal rule of thumb in the universe is, all black holes will fall into the gravitational pull of all bigger black holes and since they sometimes crowd in, more than one at a time, it is like 3 D billiards, the new incoming galaxy will act like the cue ball and striking two galaxies that are near to merging, can "kick" one of them outwards. Only this doesn't mean the escaping galaxy is dissappearing into the wild blue yonder.

Here is my schematic drawing of a non-flat billiard game.
If the cue ball hits very hard on only one of the two balls, one of them can be sent spinning away while the cue ball and the remaining ball stay "stationary" vis a vis each other, in other words, the cue ball displaces the second ball. But absolutely nothing in the universe is "stationary" except in relation to only one body at a time. The multi-level complex movements of various bodies makes the fabric of space a very complex entity. If we could see this visually, the ripples, waves and whirlpools would make an ocean in spring flux off the shores of New Foundland look placid.

It is amusing and scary to me, watching scientists riddle out this business of gravity because of course, Einstein first theorized that all things move relative to each other and this relativity warps light and fools the eye of the beholder. This caution has been overcome by using the magic of numbers to express the relative movements. But as always, one has to have a visual image to dump this data into and mine happens to be spiral/circle/round rather than open space that stretches to infinity.

Just like if we shoot a cannonball, it goes x number of meters but eventually falls back to earth. If we shoot a rocket, it goes x numbers of miles and then goes where? We haven't done any studies of this, yet. We have some probes that are eventually going to clear our solar system, they being exceedingly light and thus, able to escape the gravitational pool of the sun which isn't that great, cosmically speaking. Of course, Bush and the political tools running NASA have cut funding for tracking Voyager, for example, which is, to my mind, really stupid.

One thing is certain, in my mind, there is no way Voyager or anything we send out, will escape our galaxy any more than our galaxy can escape all the others going towards the Great Attractor. Which takes us back to the whole business of visuallizing the universe. I would posit that many astronomers are like "flat earth" people, unable to understand emotionally, that the earth isn't the center of the universe. Thinking about space as essentially flat is wrong.

And thinking there is some "dark attractor" that isn't the Great Attractor which is "tearing apart the universe" and all that ripping of the cosmos talk is desperation, trying to think of things as if there is no gravity at work here, on a mega/mega scale.


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