Black Holes could they be an illusion

[Insane Climber]

This might sound a bit crazy but it occurred to me that Black Holes might not really exist. My theory is that all the mass of stars and dust and planets that appear to be orbiting a black hole, may actually have an average mass that would exist at the point of the hole.

To help anyone silly enough to listen, understand what I'm going on about, Imagine two stars orbiting each other. A binary i think you call it. If a third star was orbiting the two, would it orbit the biggest star or would it orbit the center of mass of the two stars. And how would this work if we added a million stars.

If this sounds like rubbish to you please tell me why and have a good laugh at my limited understanding.

Jas:rofl:

[dpastern]

I'll wait for someone smarter than me to answer this.

Dave

[Insane Climber]

Thats no fun David;)

[leinad]

sorry, I just had to :D
http://2.bp.blogspot.com/_nlB2iavXqvs/R16udh6vXaI/AAAAAAAABjo/gWDuSwWVG8I/s1600-h/Black+Holl+Sun+Optical+Illusion.jpg

Be interested to hear some comments on your question from the masters. :whistle:

[AstroJunk]

For a great many years, the established theory of galaxy composition did not require a central super massive black hole. Globular clusters certainly do not contain black holes as you have sort of deduced. So the simple answer must be, if you have sufficient mass - no.

So I guess you will have to get out and weigh a few galaxies to disprove the existance of black holes. Don't worry if you can't find enough mass straight away, you are alowed to add as much 'dark matter' as you need to make the equation fit :P

[mswhin63]

This idea was put to me as a young apprentice nearly 30years ago, do Black Holes really exist? Never really thought about it until reading this thread.

Einstein theory (layman) if there is any mass the gravity should not be strong enough to pull in all light. E=MC2 this would means the mass inside the black hole would have to be pure energy. Pulsars seem to come close to the mass versus energy where some light escapes.

So if Black holes really exist and no light can escape this means that instead of mass being in the centre of a black hole it must be all energy.

Or just another theory not yet discovered.

Interested.

[sjastro]

Black holes have signatures that a centre of mass doesn't.
For example one doesn't get accretion matter forming around a centre of mass.

Particles of accretion matter falling into a black hole can collide prior to passing through the event horizon and are a source of X-ray radiation.

While this phenomena can also occur with other massive objects such as neutron stars and white dwarfs, since accretion matter is colliding onto a surface, the surface warms up and emits infra-red radiation.

Black holes by their nature are defined by an event horizon and not a surface and as such cannot emit infra-red radiation. Any form of radiation (except Hawking radiation) cannot pass through the event horizon back into space.

Regards

Steven

[xelasnave]

Well of course black holes are an illusion :)... they are an extrapolation of the math of GR and even Dr A felt such a step was unjustified:eyepop:...however for what ever reason they have become a favorite flavour of both scientists and lay people... I blame the movies..scientists get to feel they have a conection to something trippy:)..as the movies train the public to believe... and the public are just as inclined to believe in black holes as much they are about to believe the latest "buffy" or "supernatural" tv dribble..yes bribble... so where do we get the black hole concept..from math extrapolation from a theory that says we can understand the Universe and gravity if we think about a human in a lift.. no I am not kind to GR but its influence on finding what we expect and want to find must be halted... remember the math of gr will be correct.. it is not the math that holds any fault but the premise upon which it is built offers room for extreme doubt as to rightfull application and therefore doubt as to any propositon built from such original premise... GR gives us black holes and dark matter and conveniently we can see neither... well math will not convince me the original premise was reasonable... dark matter..90% of our universe whatever we cant see..really who can buy that????

The suggestion that a black hole system comes from a binary relationship offers more reasonable expalaination of the observations than does GR:thumbsup:... I believe we will not find a single "black hole" but a binary system the creates exterme gravitational influences... such a system offers better explaination of the "jets" and gr for me glosses over exactly how such jets can be generated..(that is my view based on a limited view etc and I am happy to be corrected in the interest of gaining better knowledge)...
So I say that black holes and there reality are not established... and dont give me a list from NASA their list is of spots that show signs consistent with the presence of a black hole on their approach to their existence...
AND on all this I am sure no one will disagree now that I have explained it so well:rolleyes:.

alex:):):)

[Insane Climber]

Now That is funny.

I take it from everyones answers that apart from Mr Hawking, no one has any idea what a Black hole is. And apart from the apparent massive gravitational pull at the center of a galaxy, there is actually no proof they even exist. Oh hang on Hawking predicted the hawking radiation he must be right.

This leads me to ask. Why is it that astronomers talk about such theory's as if they are real? No wonder the general public raise there eyebrows whenever i mention i am interested in astronomy. It all sounds like a load of hooey.:screwy:

Kind regards
Jas

[GeoffW1]

Hi,

A lot of people will think you mean astrology ;). Certainly if you say something like "Oh, the moon will be in Leo tonight" when thinking about where to look.

Cheers

[dpastern]

I've actually done a fair bit of reading on this subject. Might I recommend Black holes and warped space time by William Kaufman III. It's an old book now, but it's still pretty much valid. The wiki entry covers it reasonably well:

http://en.wikipedia.org/wiki/Black_hole

Dave

[sjastro]

Black holes are a logical outcome of Einstein's field equations in GR.

Detecting black holes is only a matter of time.

http://www.newscientist.com/article/mg20227091.200-coming-soon-first-pictures-of-a-black-hole.html?full=true

Regards

Steven

[dpastern]

Scientists are certain that there are massive black holes at the center of each galaxy. By observing star movements around the centre of our galaxy, they can deduce the mass of the object that they are orbiting. There is no way as far as we know that something with 2 billion solar masses can exist and not be illuminated, unless it's a black hole.

The process of stellar evolution will pretty much guarantee supernovas, pulsars, neutron stars and black holes. I don't pretend to be an expert, and I can't remember the entirety of the technical arguments. Black holes fit in with galaxy evolution too it seems, at least according to the most recent research. Scientists now think that black holes come first, followed by galaxy evolution. Maybe in those very first instants after the big bang, physics was different, and ultra massive stars with billions of masses could develop. The larger a star, the shorter its lifespan..

Dave

[Insane Climber]

I think you guy's just overloaded my brain, i can't stop thinking about black holes now,

Is it possible for an amateur to detect any of the effects of a black hole? It seems to me that possibly we could see the effect of gravitational lensing.

This link has some animations and video of the centre of the milky way taken over 16 years
http://www.eso.org/public/outreach/press-rel/pr-2008/phot-46-08.html

[leinad]

http://www.newscientist.com/article/mg20227091.200-preparing-to-peer-into-a-black-hole.html

[mswhin63]

For Backyard astronomy I don't think it would be possible. I watched a podcast on 365dayofastronomy of a young Norwegian girl with no experienced joined Galaxy Zoo and discovered a once only anomoly.

Now it is called Hanna's Voorwerp (Hanna's Object). She emailed Galaxy Zoo's administrator said some strange thing and was given the object her name. She hasn't even got a scope.

[Robh]

I'm may not be the best consultant on black holes but this is more about what constitutes sufficient evidence for a theory.
Are black holes just an illusion? Certainly their existence hasn't been proven without a shadow of a doubt; as witnessed by published lists that refer to these objects only as possible candidates for black holes.

The theoretical existence of black holes was predicted long before any candidates were found. The Schwarzschild radius describes the size of the sphere that a mass must collapse into and become a black hole. The surface of this sphere is popularly known as the event horizon. For example if all the Sun's mass were squashed into a sphere of radius 3km, it would become a black hole. General relativity provides models for the effects of black holes on matter and space but it does not prove the actual existence of such objects.

So what constitutes sufficient proof in science? The theory must explain observations and be consistent with all known facts. Continued observations must confirm the theory and verify any predictions made by it. This is the position with the theory of evolution. No new evidence has arisen to put it in doubt.

Where do we find some likely black holes (or BHs for short)?
BHs often form accretion disks and associated relativistic jets. These interactions cause strong X-ray and gamma ray emissions. The nuclei of quasars are believed to contain super-massive BHs that power accretion disks. There are more than 200000 known quasars.
Some strong candidates for super-massive black holes are Sgr A* in the Milky Way core and at the core of M87.
BHs may exist in binary systems. A BH might be seen to accrete matter from an orbiting star. This is the believed scenario for Cygnus X-1.
Gravitational lensing might turn up some evidence for BHs.

So what do we get out of this? Theoretical physics say BHs are possible. There is a huge number of candidates which appear to exhibit BH activity. New observations are producing better evidence for BH activity. It appears BHs are the most feasible explanation for the observed phenomena.
With better understanding, astronomers are developing more definite signatures for BHs e.g. event horizon dark shadow or evidence of frame-dragging.
Do they actually exist? My feeling is that the evidence is building to a strong "yes".

Regards, Rob

[Astro78]

Great proposition Sir and this cannot be laughed at - Posit: 1.Gravity is weak especially at distance. 2.The quantum world is increasingly bizzare (not holding our understanding of the 'rules of the game', ie> anything goes, or at least with 2009 understanding). 3.Matter as we see and detect it will change greatly in the future. 4.Understanding of time is our greatest error. 5. We cant see the link yet between 'our world' and the quantum, so it doesn't exist - frack that!

PS: Steven is spot on btw. The above is pure posit

[Enchilada]

Black Holes could they be an illusion ?

This is like asking does an observer inside the event horizon know anything about the Universe. I.e. Universe(s) could they be an illusion?

[mswhin63]

A lot of our advancments now-a-days has been from Theoretical Physics with their eventual ways of practically demonstrating them.

They form an integral part of the need to understand our universe but we can't dismiss other non qualified people as well, as in some cases some of the simplist ideas turn out to be correct.

So far without the Theorists we wouldn't be at the stage of trying to generate a Black Hole to understand. I believe it could be close to a solution but need to be prepared tfor the practicle outcome may not be what people expect and sometimes it is difficult for people to let go. :ashamed:

Either that or the experiment fails. :doh:

[Insane Climber]

I have found this discussion very usefull. Even though i know very little, I now know a lot more than i did. Thanks everyone.

Clear sky's

Jas


It's better to look like an idiot than to be one.;)

[taxman]

Actually, the third star would orbit neither of those options - it would orbit the centre of mass of all three stars. But depending on the mass of each of the stars and their angular velocity, that centre could be anywhere in the space enclosed by the three stars - even at the centre of one of the stars themselves.

Adding a million stars of varying mass into the equation makes it muddier - the centre of mass could be anywhere at all and only by observing from outside the system could an estimation be made where the centre is.

However, it would be unlikely the centre of such a system would be dark as there would be lots of stars with low angular velocities and/or mass orbiting a very short distance from the centre of gravity of the system.

Unless there was a large, super-heavy, unobservable object at the centre sucking away these "rogue" stars, making them in turn unobservable, our observations of a hole in the centre of galaxies would be the exception instead of the norm.

[hickny]

Astronomy magazine has a recent article on Black Holes...
http://www.astronomy.com/asy/default.aspx?c=a&id=8308

[GrahamL]

http://en.wikipedia.org/wiki/Karl_Schwarzschild

Read a fair bit on the guy over the last year or so .. I read Albert wrote to thank him on the publication of his paper regarding his solutions to the field equations einstein published the previous year ..
While Karl could never know the significance of his publication
..Dieing shortly after , aside whether you believe a black hole exists or not , the mathamatical solution to show they VERY much can ..hasn't really been disputed for over 90 years .

[higginsdj]

There is a slight problem with your theory...... It still is based on teh physics of 3 solar masses and has to obey the physics related to 3 solar masses.

When orbiting objects are observed to obey rotational dynamics related to 1000+ solar masses and there are not 1000 solar masses of stars actually observed in the system what then? The observational evidence outweighs your theory somewhat. You may not beleive in Black Holes but how do you account for the lack of observable mass? Localised Dark Matter perhaps....

[dpastern]

Einstein pretty much proved that Newtons laws of gravity weren't wholly accurate. For the planets they're mostly OK, but not totally accurate. Einsteins theories have been proven many times to be on the money. Gravitational lensing exists, and initial experiments have shown that time/space does curve. There's a probe due to go up in the next few years that sets out to prove time/space curvature beyond a doubt.

Black holes were first semi described by a astronomer a few hundred years ago - very loosely formulated in rough principle. I'm trying to find the guys name, but it's eluding me at the moment.

I really do recommend reading that book I linked to in an earlier post, it's a very good read.

Dave

[sjastro]

Pierre Simon LaPLace postulated the existance of Black Holes in 1795. Unfortunately in the context of Newtonian physics it would not have been possible for him to come up with the correct mathematical model.

The divergence of Newtonian physics from GR is apparent in how each theory predicts the velocity of an object falling into a black hole as measured by an observer outside the event horizon.

Newtonian physics predicts a steady increase in velocity which reaches a maximum value at the event horizon.

GR on the other hand predicts the object reaches a maximum velocity at 3 times the value of the radius of the event horizon, then begins to slow down. Finally at the event horizon the object is stationary.

We will never see an object actually fall into a black hole.

Regards

Steven

[dpastern]

:-)

Dave

[xelasnave]

:whistle:I recall that "black holes" are only found in a binary system :shrug:... this is or is not a fact:)... I mean I really dont know but I have read that someplace...

I think we think General Relativity will describe everything we seek to observe and that seems rather silly... Folk claim general relativity is a given but what if it is not..after all it is based on a premise which for mine seems irrelevant to how the Universe deals with gravity...

Therefore one could be cautious in concluding that black holes are a given in the form spectulated...

There is no doubt about the observations as to lensing,for example, but General relativity is only a geometric description of space so it seems difficult to accept that the observed geometry can make reliable predictions... geometry describes what it observes one would think and not elevate itself to the role of prediction...A man excited with the notion of general relativity driven to distraction in a trench in the first world war came up with the black hole concept as I understand ..Dr A the presenter of the geometry of General relativity did not go alone with the notion ...and I am inclined to back him over others...

If black holes exist they have little influence on their galaxies (if they are there) .. whereas we are presented with the notion that they are absolutely central and controlling upon galactic evolvement..how could this be so if their influence is so minimal when it reaches us let alone the outter regions of our galaxy....consider what influence does sag A have upon our region of space...zip thats what:eyepop:..how much mass do you need in a black hole given the inverse square rule to "balance" or influence the gallaxy..well it seems we need much bigger than sag A:whistle:....so I dont see their value on "control" of the galaxy...anyways thats my effort to spark some thinking on these matters rather than settling for a simple acceptance of what we are fed....:D

alex:):)

[astroron]

There seem s to be confusion as to solar type "Black Holes" and million solar mass "Black Holes" .
People seem to be jumping from one to the other:shrug:
They are different beasts with the same name:screwy:

[Robh]

Alex,

I think the evidence for the supermassive black hole in Sgr A is proving to be fairly strong. However I agree with you on the point you made above.

Out of curiosity, I did some rough calculations on the Sgr A* supermassive black hole of 4 million solar masses, distance 26000 light years. You would need roughly 37000 such black holes at the centre of the Galaxy to produce the same gravitational force on our Sun as the Sun would have on the planet Neptune. I would have to say that its gravitational effect is fairly insignificant at 26000 light years.

Anyone with some maths knowledge can check these calculations ...
Mass of the Sun is 2x10^30 kg, mass of Neptune is 10^26 kg.
4 million solar masses is 8x10^36 kg.
One light year is 9.46x10^12 km.
26000 light years is 2.46x10^17 km.
Distance of Neptune from the Sun is 4.5x10^9 km.

Using the formula F/G=Mm/r^2 gives a result for
Sgr A* & Sun of F/G=(8x10^36)x(2x10^30)/(2.46x10^17)^2=2.7x10^32
Sun & Neptune of F/G=(2x10^30)x(10^26)/(4.5x10^9)^2=10^37
10^37/(2.7x10^32)=37000

Regards, Rob

[xelasnave]

I dont argue that there is no sag A as we get data saying something is there:)..it is called now sag a and most will say it is a black hole... therefore it will be in the form we hold in our minds, a traditional although super massive black hole built from the extrapolation of general relativity to produce such a unit:D... all I say is although observations are consistent with the "black hole" predictions I see no reason to exclude other explanations or interpretations of the data...

I defy anyone to show how a black hole in whatever form you conceive it to be can produce the jets they are believed to be responsible for...yet when one considers how a binary system could produce a massive jet it jumps out as being mechanically achievable and indeed simple:whistle:....particularly if:):) ..like me you take into account how gravity must work at a physical level as oppossed to a geometric construct born from mind games:)....with respect to Dr A... he also thought little of the black hole concept :eyepop:as I said.

Black holes have run away with our imagination and are attributted with properties that suit Hollywood more than the lab in my view... clearly if one actually does the sums one finds their influence is nothing like we have built in our minds... sag a but one example...there are many reports of super massive black holes but who takes the time to work out how massive they need to be if they are to rule the galaxy by gravity...man it would be so massive ..actually any black hole will have to many times more massive than its host galaxy :eyepop:...the inverse square rule will produce some big numbers as to mass for a black hole if it were to influence even a grain of sand at the edge of our gallaxy... so how would you go with sombrero galaxy or other biggies...how massive do we need a black hole in m87.. consider some of the diameters of galaxies and then let the inverse square rule take a meaningful grip on its expectations of central mass and galactic influence...

To me the main reason I find attraction unacceptable as the "method" of gravity is the problems it and the inverse square rule generate that seems attraction would never "hold" a galaxy together...needless to say a galaxy can only be held together by an external influence;):whistle:... the outter stars rotate faster than they should from the current approach so we need dark matter:mad2:...not so an external pressure will explain it much more simply:)..pass the razor:lol:...


Anyways if they call it black or dark (dark matter) and say its there but we cant see it lets seek more reasonable and realistic explanations of how it all works.

Man we now have dark matter 3d maps... but just look at how they worked out the lensing... I can not see they are right, they have come from the ball and the blanket example to do their science and to me obviously absolutely flawed... but like the effect of super massive black holes on galaxies who actually questions these propostitions... dark matter is unsupportable and the current 3d map really proved it to me..if others cant see it that is not my problem...

We find ourselves where we are via math /geometry extrapolations originating from original general premises..General relativity comes from a premise I believe is irrelevant to considering how the Universe works.. how a man experiences a ride in a lift just does not do it for me...and yet from a simple premise all we have today has grown...All I ask is what if that premise is indeed flawed and inappropriate... what then...will we still have black holes and dark matter?


alex:):):)

[Zaps]

"I don't know what you're doing, therefore you don't know what you're doing."

[DJDD]

was this supposed to go into the "favourite Quotes" thread? :P

[xelasnave]

And another thing ... the observer does not control the outcome ..what is out there is what is out there... it makes no difference how I or anyone else speculates upon unknown facts... the facts will always be the same irrespective of the great or less great minds who indulge such speculation.

But I can easily accept that my views are held by a minority of one:eyepop:... and that is me:D...on the up side 100% of the minority group agrees with my view not insignificant if you suspect you have a multiple personality disorder:whistle:.

So how massive do we need to have sag a to influence gravitationally a grain of sand on the edge of our galaxy:shrug:... lets settle for a radius of 100,000 light years maybe that will make the math easier... more importantly how could it influence anything gravitationally...given its gravity is so great nothing can escape which one could presume to include the "message" of gravity from our black hole to the rest of the Un iverse... When one thinks about how "messages" are communicated between objects ..particles... the suggestion seems to be it is done via messenger particles... well how do they escape the black hole..light can not so why should gravity do any better... if one faces the necessity of some form of interaction to effect gravity one will arrive at a similar point to me... General Relativity is geometry it does not control space it presumes to interprete space... and so we must therefore look at how the arrangement we call a black hole can actually interact with other bodies... its gravity is not generated from the geometry although given the focus on GR most think GR somehow magically controlls space...not there must be a physical mechanical explanation ..which one would resonably presume requires something to leave the black hole to tell the rest of the Universe it is there... I know thinking makes ones head hurt but is there not something interesting about my proposition... how does a BH send out a message of gravity???

alex:):):)

alex:):):)

[DJDD]

I thought the "current thinking" on super-massive black holes influencing their host galaxy was not so much the "here-and-now" (i.e. once the galaxy is fully formed) but during the inception/formation phase of the galaxy.

Would this not be similar to a star's influence on a solar system during the initial formation stages. after that, multiple-body interacvtions may take over.
(i realise the analogy breaks down a bit since a solar system is not a galaxy.)


From "small thing" big things come...

[xelasnave]

I cant argue against what you present.
I have read stuff along such lines and stuff that tells how black holes in effect "clean out" the inner regions of the galaxy. The only problem with a parrallel between a solar system formation and a galaxy may be distance... I simply think that when one considers the limited influence even a super massive black hole can only have by virtue of appling the inverse square rule one must ask well just how far out can it gather in matter ..also we now have the question ..how did galaxies form .. the same size as we see them now??? Do they eat as they go...it seems yes they do... our galaxy seems to have eaten smaller galaxies so it raises the question ..what size was it when it set out.... The time limitation dictated to us by following the big bang idea seems to eliminate a growing and seems to suggest all gallaxies started rather large..compared to a solar system... eating a few neighbours as it aged.
I dont know obviously..but neither does anyone else for sure irrespective of the merit of the theory (big bang) ... I dont like big bang in its current form as I am not happy with the inflation aspect which for me makes it laughable as a realistic theory of the start of the Universe..still thats my view..inflation is accepted ( without experiment) .... were the galaxies formed before or after inflation for example... if before mmmm if after mmmm anyways... I bet we never actually can prove black holes are there... beyond doubt..er my doubt that is... and why do they have to be black..if light cant escape and it is "white" wouldnt that mean the black hole is in fact white???
Thanks for your input but dont get sucked in by black holes:D
alex:):):)

[Robh]

I've been thinking about this one. The Sun takes 220 million years to orbit the Galaxy centre. Whether it is the Sun or a grain of sand at our distance, the orbital period has to be the same. The period of orbit depends only on the mass of the central body and the distance of the satellite object (T=2pi x sqr(r^3/GM).
It is not the mass of the orbiting body that is important but the speed that it is orbiting at. Theoretically, our Sun could orbit the Galaxy centre at a billion light years distance but it would have to have an orbital speed near zero or it would shoot off into space. In reality, at this distance, other bodies beyond the Galaxy would start to affect it's orbit and pull it somewhere else anyway.

However, the Galaxy is a multi-body object. The central supermassive black hole would affect stars immediately around it and each star in turn would affect more stars as we move further out from centre. The overall affect is like a slowly spinning web of connected stars.

If the galaxy's central supermassive black hole existed before any significant external star formation, its affects could theoretically go out to great distance pulling gaseous matter around it into a large disk. But after individual star formation, the stars in any local region would have greater affect on each other gravitationally.

What you say about Black Holes is interesting- if nothing escapes e.g. light then how is gravity propagated? Well, it seems that it is propagated, so I guess it is an exception to the rule. Often happens in science.

Regards, Rob.

[sjastro]

Alex,

Why should a BH effect a grain of sand 50,000 light years away?
You might see it as a major issue I see as irrelevant.

I assume a "message of gravity" is the quantum mechanical version of gravity, the graviton (if it exists).

The answer is quite simple, like the other force carriers (photon, W and Z bosons and meson/gluon), the force of gravity is created the instant the graviton is emitted.

Regards

Steven

[xelasnave]

Thanks Rob and Steven for your consideration and comment.
I understand the matters relating to orbit speed etc... my selection of a grain of sand was to have an object that would take little to move... so if the bh can influence something lets try a grain of sand... I would have thought the black hole would be massive beyond reasonable limits if we are to conclude it can influence all the gallaxy via gravity... as to a pass on effect from star to star ...yes interesting but I feel such a system would not hold a galaxy together..but then I am pushing the exterior force idea so I will be careful and think longer about such a system.

Steven all I am pointing to as to the message of gravity escaping a black hole is simple... our sums tell us nothing can escape yet it must..at least the mythical graviton I would reason is/if created and must travel to other parts of the Universe to get the message of gravity to another object... well if the gravity is so strong one could expect that not even a particle can leave...be it a photon or a graviton... the bh sums say they can not leave .... mind you I dont believe in the graviton as it no doubt works via attraction and as you know I say attraction is a mythical force which does not function in reality...gravity works via push I feel and in that case nothing need leave the black hole to communicate gravity as the gravity comes from the exterior a pressure is a way of looking at it I guess... so we dont have any messaging problems as I raised for an attraction system... sorry folks I have tried to give it (push gravity) up but here it comes again...I am sick of it so I appreciate all of you must feel similar...thanks for the well considered comments.

alex

[sjastro]

Alex,

The point is a BH doesn't doen't influence the entire galaxy.

The total solar mass of our galaxy is 5.8 X 10^11,
The BH is 4 X 10^6.

The solar mass contribution of the BH in the galaxy is only 0.0007%.
The BH is not the engine room of the galaxy.
It's only stars in the neighbourhood which orbit around the BH.
All other stars orbit around the galaxy's centre of mass which is not necessarily the geometric centre of the galaxy.



In the 1960's a NZ physicist came up with a solution to Einsteins field equations in which the black hole could rotate.The BH also has 2 horizons, the familiar event horizon and the ergosphere.

It is a BH that can actually repel charged particles which seemed to violate the very nature of a BH being a powerful gravitational sink.
What happens is that matter falling into the black hole collides with other matter and generates X-rays. The X-rays ionize some of the accretion matter into charged particles. If the charged particles fall into the ergosphere the particles rotate in the horizon and generate an electromagnetic field.

The BH is able to align the field lines so that charged particles get swept up in the field and ejected in the form of relativistic jets.

It is this type of black hole that reveals itself in the form of X-ray binaries.

So as you can see gravity doesn't always win with BH.

Regards

Steven

[xelasnave]

Good morning Steven:hi:.
I am delighted to read your post :)... as usual you are so helpful and informative:thumbsup:...of course I know everything you say but I am sure it will help others:whistle:... no in truth I never have read a note on how the jets form using the GR approach. Thanks specifically for that new info (to me):thumbsup:

You said........

The point is a BH doesn't doen't influence the entire galaxy.

The total solar mass of our galaxy is 5.8 X 10^11,
The BH is 4 X 10^6.

The solar mass contribution of the BH in the galaxy is only 0.0007%.
The BH is not the engine room of the galaxy.
It's only stars in the neighbourhood which orbit around the BH.
All other stars orbit around the galaxy's centre of mass which is not necessarily the geometric centre of the galaxy

:)AND I say yes indeed:)..my point has been made by you :thumbsup:... it has seemed to me "others" think a black hole is the engine room and all I have said before in this thread has been to make that point.

Although science is happy with the current explanation I still hold with my push view of the Universe and entertain both a GR universe and a push universe... and I realise my approach is not even poor philosophy and morosophic in the extreme... and I thank you again for your tolerate approach when we discuss these things... my style sometimes could seem dogmatic but I am even and open mined with an unhealthy curiosity in these matters:screwy::rolleyes::whistle:: lol:.

Have a great day:thumbsup:.

alex:):):)

[Robh]

Alex,

Maybe you've explained your view somewhere before, but since no-one else has asked here ...
For what reason would you postulate gravity as a pushing force?
Just exactly how does this mechanism of push work with gravity? Something must be doing the pushing. Example, with Solar wind, you have a stream of energised charged particles. The effect can be seen in comets where the tail is blown in a direction away from the SUN. Hypothetically, a large sail in space could be pushed by photons. However, the particles in your model must also emanate from a power source or are they just buzzing around in space (the "ether" revisited). At what level of matter is the pushing being done?
And, for moving bodies, won't these particles in space create drag?

Or, as in general relativity, is a massive body simply a sink in the curvature of space where other bodies just roll in as it were. It is possible that mass simply affects the curvature of space and no particle is actually associated with gravity. It then begs the question as to what space actually is.

Curious, Rob.

[Insane Climber]

Well this is all very interesting, My theory on center of mass has not been disproved. Nor has the idea that a black hole may in fact be an effect, not an object. I now understand that the center of mass could never pull all the matter together in a galaxy, but then neither could a Black hole.

So the question i now think is relevant is. How do galaxy's so often form into nice pretty flat disk shapes with limbs. If a galaxy formed around a black whole wouldn't it be more 3D? I know people talk about black holes like there some flat circular doorway into another world. But there not are they? they are Spheroid aren't they?

Of course i am leading back to the idea that a Galaxy first formed around 2 objects or stars orbiting each other. This to me would explain the shape and limbs that galaxy's form. As 2 objects orbiting obviously form a flat disk!:eyepop:

I keep coming back to one thing which has me really stumped? why are there so few collisions?:help:

Jas

PS: It's STILL cloudy in Sydney :(

[xelasnave]

Rob thank you for asking about my thoughts about push gravity:).
You may regret it and I can imagine some members reading you post will be saying "Oh no dont get him started he will never stop...":scared:

For some years I have held a belief that gravity works along the lines first put forward by Le Sage in 1745.
I suppose it is aether based in so far as those who subscibe to the notion imagine there is a flow of particles from every star (and other bodies no doubt) in the Universe ... maybe a particle contained within the electromagnetic spectrum... neutrinos could be the sort of thing I speculate upon:shrug:.. however the flow of all these particles in effect create a pressure in space in fact I like to think space is teaming with particles..a somewhat infinite flow...

A mate of Newton was into the idea of push gravity (I cant recall his name) and I am confident that Newton was exposed to the idea... rather than embrace such a mechanical approach when asked what was the force of gravity Newton replied that it was the force of God which I find interesting as his push gravity mate was hunted down by the Church and done in:eyepop:..apparently for his unhealthy influence over children but of course I see a conspiracy by the church not to let the power of God be subject to any further errosion:rolleyes:...

In such an environment of particles everywhere (all travelling at C or near it ...and I believe some nuetrinos have been attributted as near C) I speculate that gravity manifests via a shielding effect:D...so we are stuck on the surface of our wonderful planet because the flow from above is unimpeeded whereas the flow that comes from under our feet has travelled thru the planet.... and so we have an imbalance in this flow which causes the effect most mistakenly call attraction but it an imbalance in the flow ..or gravity:D (The flow for most purposes we could call the aether lets not get into the problem with it carrying light whatever... I know about the MM experiment but say that the gravity B probe in a mechanical sence is also mapping the path of the aether...anyways dont worry about that for the moment... just consider the particles flying about neutrinos etc and ask what do we call such if not the aether the ancients speculated upon)

Or think of it this way..you mention the solar wind..think of all the solar wind from all over from everywhere all stars... and if you are in a strong wind and sheltered behind a shed the shed may seem attracted to you but it is being pushed by the wind...as you would be pushed to the shed if on the windward side...actually add sand they can be our mythical particles for the sake of better metaphore... now dont take too much literal I am trying to cram a fair bit into a small space:D... if you are really interested have a look at the site Ron built (below) I have been babbling about push gravity for years and Ron and others have placed it in the 2%ers club site:thumbsup:...
Now as to space drag I suggested space would be sticky ages ago and that what the pioneer craft would run into sticky space when they burst thru the heliosphere and that they would slow (and in fact in time will appear to stop and then accelerate until they appear to be racing away from us at (whatever speed our solar system is orbiting the centeral ..lets call it a black hole to keep everyone happy:)... I think its 350 klms per second but not sure without looking it up..orbital speed anyways..now it seems that the craft are slowing... NASA though otherwise and are somewaht at a loss to explain the observation and suggest leaking "stuff" slowing them whatever...but I say it is simple, the push of stella space working to grab them whilst the rest of the solar system continues..or the drag of all those particles... anyways at last peek they were slowing ..if it is leaking fuel or coolant they will stabalise at a new relatively constant speed...however if not a leak they will continue to slow... so time will tell if they can keep track of them...and if so we will have observational evidence that space does in effect drag which comes about from the aether or whatever we need to call it when the concept is resurected:D... as it will have to be I feel:)..what will we call all the HB's flying everywhere??? they can not be confined to existing only in stuff one would think but I expect we could expect them to be everywhere..another part of the flow you see:whistle:...

General Relativity is geometry and as such it can not control or influence space ... General Relativity revells in the fact it requires no force... well of course it requires no force because it is the observation and not the machinery of the Universe... General Relativity (as I understand it and I do not pretend to understand it very well which means I am presumptuious when even taliking about it) as I said is geometry and can only ever be how we record how mass and space relate... and mass and mass of course...

Curvature of space surely is a comment on the space time grid as mapped by General Relativity... The "cubes" of our 3d (er 4d) grid become smaller the closer to mass reflecting greater gravity and as such enables us to have a map of space and a way to place within it matter (with mass of course) ....so I simply say this.. General Relativity offers no force for gravity:eyepop:, neither attraction :thumbsup:or push :eyepop: gets a look in upon my understanding:shrug:.. the force comes from the math itself:D... and as such Dr A in a masterful stroke took science forward and like Newton had the good sence not to bring up the aether or erode the force of God for certainly I can see no other force as responsible for gravity in the GR context...

What is space...

Space is everything ..we are in effect in space..those gaps in an atom are space... space is the flow of all particles able to do so in everydirection from every body and every time...think of it this way..hold up your finger and ask what particles reasonably would reach this point...well when you think it thru something from everywhere will pass that point and that is true for ever point in the Universe.. and when one thinks about it that way it is not a long strech to imagine that all these presumed particles must push and places of greater or lesser pressure will present to us as gravity.

Yes I have a TOE is back in general chat someplace and it is constructed upon the push approach to the Universe...

That you for asking:thumbsup:.

alex:):):)

[sjastro]

I'm afraid it has been disproved.

Astronomers have found a star known as S2 which orbits Sag A* which is at the centre of our galaxy.
Since they know the orbital properties of S2 they are able to calculate the mass of Sag A* which is 4 million solar masses. Sag A* is also a radio source.

It appears that Sag A* may not be at the exact rotational centre of the galaxy so it to will orbit around the centre of mass.

Regards

Steven

[Insane Climber]

That only proves that there is a very large mass there. And as you can probably see by the discussion so far we all pretty much agree that no one knows what a black hole is. And also please remember that i have very little idea what I'm talking about. I only started this discussion to learn. The thing i didn't expect was a bunch of people who keep telling me that "Astronomers" Have it all worked out. Come on guy's. I'm just having some fun here, Now how about coming out with some thought of your own. I read all the magazines too you know.

[xelasnave]

Needless to say I have certain views on why galaxies are flat and indeed our solar system is flat... it is only an idea and at this point I say be careful placing any faith in anything I have said ..my views are not always accepted by everyone...er enyone actually...

Think of it this way ... in the case of the Solar System (this idea breaks down with the lack of influence of a balck hole when applied to a galaxy dam it:lol::lol::lol:).... our Sun travells along and the planets tag along ..the only way you can maintain a stable structure is if the system travells like a pie in the face or the plane of the system is at right angles to the direction of travel..in fact it is not right angles in the case of our solar system because of something else:D ... but it cant travel like a frizbee because the trailing edge would be far out and the lead edge too far in... sorry its hard to explain:whistle: ... however now we have established the lack of influence via a black hole it is not the same as our solar system as our Sun has influence over its entire domain..and if the galaxy was travelling like a pie in the face they would be cone shaped :shrug:.. mmm ... this is interesting I need to rethink everything..:eyepop: forget everything I have said I am going to rethink everything:D.

alex:):):)

[xelasnave]

Er I thought I came out with a few ideas which present as novel in so far as I dont think anyone thinks along similar lines...

OK how about this... a galaxy is actually like a CD or DVD disk... there is actaully a hole in the center created by a binary system of huge bodies but through this hole one side of the universe flows to the other and this flow drags material which we see as massive jets and blame on a black hole:P.

The fact is we are very priveledged humans to be able to consider these matters. The math supports the notion of a black hole which although an uncomfortable recognition may well be correct... the fact is there have been the best brains in the world developing the ideas and more importantly the math in support so that even in the absence of direct observation the various "other" observations do point to the speculated black hole being a reality... what is unfortunate is most of us learn about them via the Simpsons or some other movie or hype that takes them into a different realm add to that the nonsense we see in science reports that in an effort to be entertaining perhaps create many misconceptions... I still dont know what in my mind is a misconception or not so I constantly question anything I think I know about anything...

alex:):):):)

[sjastro]

A good example of Zap's quote in this thread.:)

So you agree there is a large mass there. So therefore a BH (or whatever you wish to call it) is an object and not an effect. You have disproved your own theory.

[Robh]

I was having some fun here. This has been an intellectual adventure for me, both hypothesizing and listening to other contributors' opinions. When people put forward the "what ifs", you've always got to have a good think about the feasibility of their suggestions. Obviously, this has to come from some knowledge base and different people know different amounts about different things. All in all, I think the thread has run with a fairly orderly respect!

Not knowing exactly what a Black Hole is (i.e. its internal nature) does not prevent us from actually identifying a Black Hole and predicting/observing its effects on objects around it. The external effects of a BH is primarily due to its mass and predictions have been made from general relativity.

As I mentioned earlier in this thread, just how much evidence is needed before we can conclude that any theory is an accurate representation of what we see, or in this case, that BHs exist? The building evidence from many different sources is pointing to the existence of BHs ... fast orbiting stars, galactic core radiation, accretion disks, relativistic jets, X-rays, gamma rays, event horizon shadows, frame dragging. Observations are consistent with theory and they best explain what we see (or in the case of BHs, don't see). I'm personally leaning towards their existence but if suddenly evidence points us in a new direction, I'm prepared to go there as well.

Regards, Rob.

[Insane Climber]

Yes thankyou for pointing that out. I am currently trying to rethink my view on this whole idea. Trouble is several people blew my original idea out of the water, i am now frantically trying to play catchup with all the stuff you guy's have raised. xelasnave has raised so many issues that i currently have trouble sleeping.

The truth is I am slowly starting to realise that its not a question of weather black holes exist. It's more a question of weather i can understand why they must.

[xelasnave]

Hey there Jase I am happy that you are spending your time thinking and not sleeping..after a couple of days without sleep one can move into even wider specualtion which will unfortunately be delussional...but hey so long as you think about things is the point..for all we know you may be the one whilst tossing and turning to come up with the new physics....

best wishes sleep tight.

alex

[sjastro]

General relativity is not geometry it is a gravitational field theory and forces do exist in GR provided they are external.

The basics behind GR can be understood by anyone who has done year 12 physics and is familiar with electric fields.

If one considers the space between 2 charged plates, the electric field lines run perpendicular to the plates. The strength of the field is pictorially defined by the distance between each field line. If you put a charged particle between the plates, the field lines loop and converge or diverge depending on the charge of the particle.

With GR the gravitational field lines are defined as the trajectories taken by small mass "test particles". In zero gravity the particles move at a constant velocity in a straight line. If the particles moves into the gravitational field of a large mass, the trajectories deviate towards the centre of gravity of the large mass.

Einstein worked out that the trajectories of the particles in a gravitational field is the same as a particle moving from pt A to pt B in the shortest possible distance in curved space.

A particle moving in curved space along the shortest pathway does not see gravity as a force as it is travelling in an inertial frame of reference.

If however we add a second large mass to the picture which causes the particles to deviate from their trajectories, the particles experience gravity as a force.

Regards

Steven

[xelasnave]

Steven things always make sence when you explain them. Thanks again.
alex

[Robh]

Alex,

I read your view on push gravity with some interest. It has taken me a while to go over the basis of the theory from other sources.

I've gathered the conclusions of some experts about the theory ...
Maxwell thought that the theory required an enormous expenditure of external power, violating the law of conservation of energy.
Poincare concluded that there were inherent problems with drag and heating in all the Le Sage models. The Earth would basically vaporize.
A flux of neutrinos are mass penetrating but would not be isotropic, as stars are the main sources. The suggestion that the neutrino or a particle like it would work in a quantum field theory of gravitation was disproved by Feynman.

Gravitational shielding in Le Sage's model is a violation of the equivalence principle used in general relativity. Poincare basically stated that Le Sage's model and general relativity were incompatible.

So, my question is what is it about the current model of the Universe that makes this model look at all valid? If general relativity is holding up to scrutiny, you would have to abandon this model.

Regards, Rob.

[bojan]

The answer is simple: absolutely nothing.
We went through this discussion before.. last year or earlier this year, if I remember correctly.
(we called those elusive particles "pu****rons".. "pushi-trons" or "pusitrons" .. It seems there is some automatic censorship in place here ;) ).. And with the same points and conclusions at the end.

As Alex said in his last post:




We all should take effort to remember those explanations, to avoid going through all this again in the future
Otherwise, one day Steven may stop bothering to continue giving explanations any more ;)

[astroron]

I don't know if this adds anything to the debate, but did not want to start a new thread with it:shrug:
Please advise if it it does add to the debate:thumbsup:
http://www.eso.org/public/outreach/press-rel/pr-2009/pr-21-09.html

[Robh]

I would say that there are a lot of new members who have joined IIS since this discussion took place, me included. I see no problem in asking the question and had no intention of taking the thread in a new direction. Who knows, Xelasnave might even be swayed to change his point of view!

Regards, Rob.

[bojan]

I am sorry if I "sounded" a bit jerky.. my intention was actually to add some humour to this discussion (Alex should remember.. :-) )

There is absolutely no harm in starting threads with those mind-blowing subjects :-)
I apologise if I offended anyone with my remark, really.

[Robh]

Thanks Ron,
Yes, it has some relevance.
It does talk about a supermassive black hole at the centre of the Galaxy.
Also, the upper limit of 130 solar masses for a star I think occurs because nuclear forces are greater than gravitational pressure (Eddington limit ) and the star supernovas. It is possible the resulting mass then forms a black hole. Observations haven't shown any stars over 120 solar masses. Steven might know more about this than I do.

regards, Ron.

[sjastro]

The driving force for nucleur fusion in a star's core is gravitational collapse of the core.

When a helium nucleus is formed in the core by the fusion of hydrogen nuclei, the mass of the helium nucleus is less than the sum total of the hydrogen nuclei. The missing mass is in the form of energy (E=mc^2).
High energy photons or radiation is also produced.

Nucleur fusion produces an outward radiation pressure on the core and prevents further gravitational collapse of the core. (The Eddington limit).

In very massive stars that exceed the Eddington limit, the radiation pressure exceeds gravitational collapse. This can cause the star to blow off it's surface layers. The core remains intact.

This however is not a supernova. Exceeding the Eddington limit is a temporary phenomena. The core continues to fuse nuclei.

Heavier nuclei such as Lithium, are formed in the core and in turn fuse to form even heavier nuclei.

A property of nucleur physics is that it becomes progressively harder to fuse heavier and heavier nuclei as electrostatic repulsion of the nuclei increases due to the number of protons. The amount of energy released during fusion also progressively decreases.

If the core is sufficiently massive it can fuse nuclei up to Iron.
Once the core is made up of Iron nuclei the results are catastrophic.

The fusion of Iron nuclei no longer provides any energy and cannot sustain the outward radiation pressure. Gravitational collapse takes over.

The nucleur force between the nucleons (protons and neutrons) in the core is strongly attractive. A property of the nucleur force is that it becomes strongly repulsive below a critical distance between the nucleons.

This occurs during collapse of the core. The result is that the core rebounds and sends a shockwave through the rest of the star.

The shockwave produces a supernova.

For solar masses 15-20 the core becomes a neutron star.
For solar masses greater than 20 the core collapses into a black hole.

Regards

Steven

[Robh]

Thanks Steven,
Nicely explained.

Regards, Rob

[xelasnave]

Thank you Rob for taking the time to familarise yourself with the concept of push gravity:thumbsup:.

For the sake of showing I can argue convincingly when all others are of the opposite view I will answer your questions:)... but please understand the best authority I can offer for my position is that I am always right:eyepop:;) ..so why should I be wrong when it comes to providing the theory of everything:lol::lol::lol:...

Prof Maxwell is entitled to think about the matter whichever way he wishes however I do not think he would have taken the time to really do any sums as it seems as if his reply was dismissive ... of course there is massive energy involved I expect however as I said...the probability of matter interacting with the flow is finite whereas the flow for our purpose could well be considered "infinite"... again I ask how empty is space... once we saw it so but it is not..there are billions..er trillions of particles flying around..why should they contain no energy or opportunity of interaction with "matter"... I feel it is easy to wonder if all these particles transmit any force and easier to conclude that there is a resultant pressure of space.

I feel the Pioneer craft are demonstrating that they are experiencing this pressure (or in their case drag)...before they broke thru the heliospere I said (predicted if you will) that they would slow..NASA thought otherwise..well they appear to have slowed... NASA are perplexed and various ideas have been put forward why they are slowing..leaking fuel etc... but they are behaving upon my morosophic view because space is the way I see it... full of stuff that makes a real presence more so way out there.

I never have been one to bow down simply because someone says they know the answers..History tells us that folk can hold ideas for centuries and yet when their civilation dies and is examined by those who follow the followers can look and wonder how they could stay on the wrong track for so long... AND as presumptuious as it is I say our current ideas on gravity can never be united with all the other forces... I dont know how Maxwell could reason any laws are violated if he did not consider the matter at lenght and with some sums to justify his position...Now it is all right for me to be so casual but not him... A scientis no matter how high up there must not fall victim to off the cuff comment and I believe in that instance he has simply made an off the cuff comment... I hasten to add this is my opinion ..he has his I have mine.
Poinclare raises drag and I say the Pioneer are demonstrating the drag...and the heat we find in the center of our planet is indeed the heat remnat from our particles giving up energy on the way thru..so as to have less energy on their exit providing the imbalance between stuff coming down and stuff going up..our gravity is the imbalance in the flow that has lost energy (thru the planet) and the flow that has not encounted any great degree of matter as it passes thru the atmosphere etc to reach the surface.
Why should the Earth vaporise...particularly when no one bothered to provide sums in evidence (not that I can but if they want to play the game that way folk like me can point out the inadequacy of their approach which I say, in the absence of futher evisence as to what was said and what experiments etc were offerred as back up..) but that is my view on what I know..and I dont know everything :eyepop:..who does:shrug:

Feynman was a great scientist, (he is another of my heros as is Dr A which folk may not know.) but he can prove all he likes but given he is more interested in staying within the conventional world od science I ask what other direction would he take... and I dont know how anyone can think they know the answers and on the basis of their current knowledge say they can establish this or that to be right or wrong... look at the nimbers that are play the complexities and ask is any human really capable of getting it right...apart from me of course:lol::lol::lol: I do not think anything must be set in stone ..look at how things and views change on matters one could say will never alter... however I will look carefully at what he said when I get back into this stuff... I am not focused on gravity these days.

I dont know why folk think that approaching gravity via the notion that a man in a lift can offer the key to understanding... why should this be so..seems that man thinks a little too highly offself to think the theory of everything can be born from such a strange observation that a man in a lift and measurement of the foirces at play will give a view on how it will be "all over"... I see it like working out what a horse can do by comparing it with other forms of transport... I have never found the 11 field equations which if I did physics would be the first thing you do I expect but suspect that T got into GR from the formula for acceleration due to the lift comparrison... I dont know and long to find out one day... still I say this I do not think the principle of equivalance is really a scientific approach to the matter... I think the great man himself called it a mind exercise which indicated to me that appraoch has little input from observation but came from the imagination...not that that is a bad thing as I say that is exactly what I am doing... and in fact I draw from reasonable observations to feed my imagination.

Why select the push model over the current model ... well firstly the most compeling reason is...because I never back a losser :lol::lol::lol:

In the Push Gravity Universe I can unite the forces...gravity with electricity... gravity with the atomic forces... in my view of course with no evidence etc but I do reckon it sounds reasonable.
The elves and sprites are visual evidence of the flow as it 'runs" into our Earth... the particles of the flow manifest as electrical disturbances.. they are "overflow" and a cloud interferes with the flow to get lightning in the same way a wire in a genny interferes with the flow to produce an electric current... magnetism is flow forced upon an alternative route because of interference (as with the Earths magnetic field) .... momentum again flow trapped by a moving object...

anywyas I can offer a relationship at this casual level as to how everything fits together... again my view.. I dont care if folk cant see it or if they think I am off the mark as it is my idea my opinion...

I dont see a problem in fitting GR into push gravity...the flow is what causes the space time grid to "bend" and I have no difficulty in making the two good friends:D

Thanks again for your interest:thumbsup: gravity is the most exciting subject one can consider as it is the machine that drives everything.
I hope my post is readable I have no time to re read it
have a great day

alex:):):)

[xelasnave]

Hi Bojan:hi:... I am sorry I though I had convinced you of the merit of the push universe and now you say you are still unconvinced:eyepop: look all I can say is keep at it and it will become clear in time:whistle:.

The good news is as I learn more about general relativity the more I can see it can assist the push universe so the more detailed the explanations the easier it is to move forward:lol::lol::lol:

I had given up on it but I can not resist having a chat about this stuff when it comes before me...and I would like to think on the positive that if nothing more my ramblings may create interest in not only push gravity but in GR and physics generally...as there will be some who feel they can offer reasoins why it can not work...

I hope Steven does not get tired of explaning things or anyone for that matter because it is not only us who reads this stuff and I see no harm in doing anything that may make the subect interesting to folk who have never given any thought to GR or gravity etc.

Steven not only is communicating to me matters of interest but to many others who wonder "what the heck is space time anyways".

There is a problem as the forces have not been united and until they are I feel any aspect of the current thinking can be looked at.

It is not as though I am trying to force folk to accept there is a God...a given to many... or that the stars influence our destiny:P... I am only trying to point out an approach that I really believes has merit... if it has none it will die and things like the Pioneer craft behaviour will be put down to other matters... I dont anyone has put forward time dialation for the Pioneer for example and I would have thought if GR rules (or is that special relativity?)it could well explain the matter...after all what we see may be the time dialoation? thing at play..and that will suit GR.

But please dont let me get to you because I wont lie down on this matter...
the reason destiny has selected me to carry push gravity forward it because destiny recognises that the bearer of the news will have to be tuff and not give a dam about others saying his views are wrong;)...and that someone is me:D... as you can see I am not intimidated by the great minds of history... they were men also ...capable of wonderous insites and also capable of error... if I am wrong or right it matters not what matters is that I think and have the courage to express my views...which I hope could be seen as a virtue not a probelm.

So good to have you on board with this one Bojan I am excited that you could not resist posting given your past frustration with the matters I raise.

alex:):):)

[xelasnave]

Well I saw it as humour:D:thumbsup:.
No one should get offended by anothers view and input but should thank the poster for taking time to post...

It is obvious we all like the subject matter and without someone to offer a differnet view or someone to have a misconception that can be corrected....there would be no point as everyone could sit in silent contentment that all is known and all is understood...and maybe we still have things to learn about the Universe:shrug:... we have not been long at considering how space works or in fact that it was relevant to anything really...but space is everything...
alex:):):)

[Robh]

Alex,
Thanks for your lengthy reply. I can see you are passionate supporter of push gravity and that you're not going to budge from this viewpoint easily!

Jason, sorry about the digression but I guess in some ways it's all related to gravity. Back to Black Holes.

Regards, Rob

[xelasnave]

Rob I started on the push concept (unfortunately before I knew about LeSage) as a result of not being able to come up with a mechanism as to how attraction could work... to me it seemed that there would be a message out and a message back to communicate gravity by attraction (or any attraction for that matter) and finally thought the message must be one way (push)... I still have no idea how attraction works so to a degree push won by default.

Believe me I do have an open mind but cant roll over if I see nothing that convinces me that attraction is a force and not just a boy girl thing... I think we assume too much... we see two bodies moving toward each other we call it attraction and yet as far as I know no experiment has ever be carried out to establish there is such a force.
I believe the casimer effect demonstrats push yet other see it as attraction... folk see a plus symbol and a negative symbol and automatically say each will attract the other but I feel their minds have not engaged the difficulty that attraction faces... anyways I did not wake up simply one morning and invent all this. IT has come from a fair degree of thought without taking anything known to date as a given.
There are plenty of folk developing ideas via GR it would be sad if the alternative go no air play.




Getting back to black holes we have tended to focus upon the aspect of a mass so compact that we have a body has so much gravity nothing can escape (other than the message of gravity of course) but the aspect of what happens to time is perhaps the most interesting aspect... GR I think says it must stand still...now I dont know how this can be ..the sums dictate such I beleive but I wonder how can such be so... that aspect seems so strange... I raise it as it has not been mentioned as yet.

alex

[Insane Climber]

This is interesting, I have just come accross the idea that something out there is causing everything to spin, Two Galaxy's close together seem to effect each others spin? any comments on that?

[leinad]

My understanding was that time slows at the EH, it does not stop. It only appears to stop from a distant observation. I think... :doh:

[Robh]

I think an observer A at the EH would see their clock tick normally but a distant observer B would see observer A's clock to have stopped. This is assuming gravitational forces haven't ripped observer A to pieces. Once inside the EH, time no longer has any relevance.
I'm speculating here, but in terms of an accretion disk, the outer part of the disk would appear quite active but the inner part appear quite inert. Anyone know enough for a yea/nay to this guess. From what I've read, for a spinning black hole an accretion disk would appear to wobble due to frame-dragging.

:shrug: Rob

[xelasnave]

I suspect that spin happens because the message of gravity (WHICHEVER WAY YOU PERCIEVE IT TO BE MESSAGED) sorry hit caps... is limited to the speed of light..so bodies relate to each other on a delay... or put another way bodies are relating to each other on the basis each is where they were some time ago..in the case of our Sun to us we have approx an 8 minute delay so we are always playing a catch up game and as such this is not a stable or static situation... spin would result from the catch up game everything plays with each other be it at atomic levels or on the scale of galactic relationships..
alex

[Insane Climber]

I was thinking that this spin may be the proof i need to convince myself that dark matter existed. And that in turn would be why patterns exist in galaxy formations. Just like sand on the beach forms patterns as the waves wash over it. Only in this situation we cannot see the water.
I have also heard that after about a week without sleep one may experience hallucinations could this be how astronomers come up with these theory's?:screwy:

Jas

[xelasnave]

I think the observations expected at the event horizon are one thing (and we have the never ending story ..or our observation will be eternal because of the problem of light escaping...however the sums say upon my understanding that time really stops in a black hole..what this means I have no idea but the wonderful thing about the sums is the interesting things one can extend the sums to include namely time... and as I say the sums tell us that in a black hole time stops GR either says it stops or not.. I am sure that is what is says so either I have it wrong or that is the way of it... I have seen comentary from true believers that one can expect to be able to time travell using the science relating to black holes... ticks me off but that sort of stuff is out there and not on crack pot sites but put forward by legit folks..have a look around the science daily site or the like and you will find an article along those lines... fits into the same box as worm holes..crap from extrapolation of the sums I feel.

still we need to make physics exciting so we grasp at such nonsence maybe.

To get a worm hole simply fold the space time grid as if it were a sheet of paper (which is what these notions are drawn upon) and we can connect one part of space to another... thats ok but what happens to the other sides of the universe .. the universe can not be folded like the paper that these ideas are drawn upon...

I dont care how sophisticated these ideas are they do not add up and because most folk have little idea they bow to these crazy notions as representing legitimate science... GR got up..ie took the noble peace prize with no observation or experiment and I question such an approach.. and although it has merit it can not extrapolate notions that we can bend space so as to connect unrelated parts of the universe as easily as folding a sheet of paper..but if paper is all you have ever worked with such a notion seems reasonable but for me the universe is more complex than 2d.

alex:):):)

[Robh]

By everything, I assume you mean astronomical objects such as moons, planets, stars and galaxies that spin (rotate) about an axis.
In the Universe, gases and particles eventually accrete under gravitation but are moving through space due to expansion. My understanding is that, as matter accretes and centralizes, angular momentum increases i.e. the object spins faster. Why an object spins about an axis in preference to another probably depends on other local massive objects e.g. the planets tend to spin in an axis roughly perpendicular to their orbit about the Sun (forget Uranus). Similarly for our Moon about the Earth.
I'm not sure whether all stars spin nor whether all black holes do. Certainly, the Milky Way spins, its period being about 220 million years, as do all other spiral galaxies. I would assume elliptical galaxies rotate but can't confirm this.
Two galaxies close together would affect each others spin due to the gravitational drag of stars in each galaxy at the closer points of each disk. I would assume the drag would be greater if the galaxies were rotating in the same direction. Mind you, if they were close enough together, perimeter stars would probably be ripped from their normal orbits about each galaxy.

Regards, Rob

[Insane Climber]

But didn't we already affirm that the great distance involved means that gravity would not be strong enough to pass the spin from one galaxy to another, I'm not sure of the name but there also exist particles which can become paired and even when separated by great distance will mimic each other. To me this suggests that something else is at play here.

[xelasnave]

All my views have been born from extreme torment and cabin madness...beening able to sit for weeks on end with no one to talk to in the bush for weeks the mind is not nessisarily trustworthy and I admit that is where I come from..still I bet I have devoted more time to this than anyone on the planet....
Dark matter is crap... it is needed only because attraction dictates it..push does not need a universe with 90% unseen stuff or unexplained energy... Dark matter is born from the necissity to explain why the outter stars in the galaxy move faster than our sums tell us ..well our sums work upon the notion of attraction if you substitue push the dark matter is not needed... the interesting thing is you can add as much dark matter as you like but the more you add the greater the problem because more exterior matter only will make the stars go faster and faster ..ther eis no point of equilibriam .. so I doubt if the math actually will support the notion... but who has actually worked out how much dark matter you need ...have a look at the stuff on this...it is presented as if space time bends around the mass where as even GR says the opposite..folk have followed the poor example )ball in a blanket wrap around thing) and this is not what GR says... it takes very little to see what I point to but there are none so blind as those who refuse to see... have a look at the 3d maps of dark matter and see if you can see the fundamental flaw .... not hard really...

alex

[Insane Climber]

Yes i agree that dark matter is crap, but i cannot ignore the patterns i keep talking about, and those dark matter maps give a nice answer as to why things appear to lay in patterns.

PS: I still cannot get over the most basic flaw mankind has come up with, that there must have been a beginning.

Goodnight for now and thanks for overloading my brain again. Its finally clear hear so I'm going home to burn my retinas with moon light.:eyepop:

[xelasnave]

When one invikes the inverse square rule one finds on that basis gravitational influence is not all we expect it to be...we have established in this thread that a black hole has very little influence on its host gallaxy ... what gravitational influenece exists between us and m31 for example.... attraction does not seem to cut it but an over all pressure as I suggest via the flow of paricles all over offers an "external" influence which on large scales may not be subject to an inverse square rule.

alex

[Enchilada]

Gravitation works on the inverse square rule. M31 is just influenced on multiple large gravitational sources pulling in different directions. I.e. Forming the independent motions as well! As for other 'unknown' forces, well they are not "gravitation" per se but could be seemingly that way by other invariant different and independently acting forces. Gravitation acts inverse square rule, only the other forces may not!

So I agree with you!

[Robh]

Alex,

I agree, using Black Holes to travel back in time is pure fantasy.
However, in a sense, you can go forward in time (i.e. lose time). Basically, special relativity says that time can slow down for one observer moving relative to another. If I was away for 20 years, travelling around at a speed of 4c/5 during this time, this would be equivalent to about 33 years for an observer B on Earth. When I got back, I would have skipped 13 years of normal Earth time.
General relativity says this same effect can be achieved by gravitation. For a Black Hole, the higher gravity would result in a slower time for observer A near the Event Horizon relative to distant observer B. If it were possible for them to meet up later, observer A would have aged less than observer B.

Rob

[Robh]

From recollection, what was said was that the supermassive BLack Hole in Sgr A was only a small fraction (0.0007% according to Steven) of the mass of the whole Galaxy. So its mass contribution was very small. However, I still wonder if there might be a gravitational link from the supermassive Black Hole to the myriads of surrounding stars and those beyond. The arms of the galaxy are visual examples of this link or chain of stars from centre to outer perimeter. If the Black Hole were removed would it create a visible restructuring of the shape of the galaxy?
In regard to two galaxies affecting each other's rotation or spin ...
The effect would depend on the distance between the two galaxies, but with two galaxies in reasonable proximity, the mass contribution to gravity would be relatively large and their effects on each other significant. Witness, the effect our Galaxy has on the Large Magellanic Cloud. With large structures e.g. Virgo Supercluster or something as large as the Sloan Great Wall of galaxies, I wonder if there might be a pass on effect of gravitation from galaxy to galaxy.

Regards, Rob.

[bojan]

Alex, how about throwing in some math to justify those feelings about inverse square law (or something else) etc?
In our previous discussion I challenged you (and other "pushers") to provide some derivations or links to something more substantial and there were no satisfactory answers..
So I believe it is time to abandon those ideas.
I mean, science works like this: if you can not prove the idea by calculation (that means - theory), or the observational evidence shows that something else is happening (data inconsistent with that theory) then it is time to abandon the sinking ship..
Also, on large scale, and when the matter is distributed in space more or less evenly, overall gravitation effect (force) of course does not follow inverse square law.
Actually it does, it is a mathematical idealisation and it works ONLY between two point-like masses. That means, if radii of those two masses are infinitely smaller than the distance between them then you will have inverse square law, describing the force between them.
In cases of distributed masses - like galactic cluster.. or interior of Earth, to take something more closer for example, we have to use calculus to describe net gravity force. That means, integration of infinite number of individual forces between individual (small) mass concentrations.. and in some cases it is not easy or even impossible to completely solve those equations.
There is no place for feelings here, because those relationships are much more complicated and no "hunch" can help you : unless you have a solid mathematical skills and experience with them.

So, back to school :poke:

[xelasnave]

Reading what I wrote it did not get to the point I was trying to make as I was leading up to the issue of "dark energy" which is external I understand.

Clearly the inverse square rule is a fact and in my post it would seem I had no regard for it... so my speculation was upon dark energy.

Bojan I have no problem with math and its important role yet I do believe however math is part of the evidence we need to support a premise ... now I have a premise but I do not have the sckill to offer math related proof.

Dr A's premise that a man in a lift can make all the observations that descibe the universe has been supported by the math but I still think the premise is wrong ... and the great man himself said words to the effect...it is the idea tha is important the math is only the bookeeping ... so I still reckon my idea (LeSage's idea really) is a good idea but the books still have to be put in order...

AND I can think what I like and hold any view I wish... if GR is so flash why do we not have a unification of the forces..if it is so powerful that step should be not a problem...yet as far as I know unification using GR is going nowhere...now at least with my approach I can link everything into a "neat" story of how everything works... AND I say this... NASA are very interested in ELVES and SPRITES and are observing Elves so new data is going to be available on them ...so far folk think lightning and Elves and Sprites are generated from Earth bound forces..curent thought is that lightning comes from dust and ice rubbing together style approach... and the math is available to prove it...but there is more to it ... the elves are visual evidence of some of the flow hitting the upper atmosphere, the sprites are where it jumps from the upper atmosphere to the clouds, and lightning is where it jumps from the cloud to Earth...
Now I have observed a lightning cloud flashing at the rate of 2 times a second for over and hour... and it seemed to me that there is now way that so much energy could come from the cloud... and how could we determine that energy ? but I doubt if the dust and ice rubbing together could create so much for so long... moving higher how can we explain the energy we see in a sprite and more importantly how can we explain the energy that creates an elve... look at one..it looks as if one has dropped a stone in a pond as the energy ripples over the outter atmosphere...

I saw a good show on SBS last night on the early days of astronomy where the church sought to dictate what humans could and not think or say..now in those days it was unthinkable that the greater body of thought as embrassed by the church could be wrong and as such folk like Galileo were told what they could and could not think or write about, after all everything was already known..Aristotle had worked it all out and to deviate was not tolerated ..what you suggest in that I can not hold a view that is contrary to current thought is no better than the church seeking to silience new thinking ...well I will think what I like and write what I like and hope in time, just as the majority were proved wrong in their long held views, that finally we will find that gravity is a force not driven by God but by the flow of the infinite supply of particles in our Universe and that this flow of particles is responsible for all energy ...
AND give me some credit for the pioneer prediction..after all I was right and NASA were wrong... they had their math I had my ideas... and what I said would happen is happening and that is a matter available from curent observation (athough I have not looked at what they are doing for a while so maybe NASA have developed another explaination other than leaking fuel etc... but as far as I know my idea so far is the winner...and I did not guess what would happen but thought it though on the basis that if space acted as I suspected that the pioneer would do certain things when they got thru the heloiosphere... they did what I predicted and in the absence of a reasonable expalnation to the contrary I feel their behaviour supports my view.

Thanks for posting I really enjoy being called upon to defend my position ...but there is no way I am going back to school ... have a great day.

alex:):):)



alex:):):)

[bojan]

Alex,
Your idea is not right because you did not predict anything.
In modern scientific language, "Prediction" means much more than speculation:
It actually means that the mathematical calculations were done based on theory, and that results of those calculations pointed to un-suspected effects, which could then be calculated, and if measurement results of that effect are within the error margins, the prediction can be accepted as confirmed.
In your case, this procedure was not followed properly :-)
Yes, I watched this programme on SBS, it was very interesting, but the points made can not be applied to discussions like this one that we have.
In case of church, it was the struggle to retain power over people (and to keep the income flow intact).
In our case, it is not about power over people, nor money (well, in general.... there are always greedy people around with over-developed individualities). But being a scientist is not very lucrative profession - that is why we have more lawyers that scientists :thumbsup:.
It is about the proven scientific procedures, which give results.
By following them your ideas are very easy to disprove. But only to those who accept the validity of those procedures, of course. If you do not accept them, simply put, no-one serious will consider your ideas worthy of having a look at them.
That is why I am saying again: Back to school ;)
Why?
1) you will gain tools to prove your own ideas, to yourself and then to others
2) you will be able to present your ideas to scientific community in a proper form and you will be able to discuss them with good level of understanding, on both sides
3) you will be able to abandon ideas if you cant' prove them to yourself (and to others) :thumbsup:

Of course, you have every right to think whatever you like.. but this is not the point here, right?

[xelasnave]

Mate I am 62 years old and I dont need to prove anything to anybody or go to school or get out of bed if I dont wish to... I dont care what folk think of me or my idea... All you say is reasonable but I am not on about proving I am right and others are wrong..as I have said many times.. I entertain a Universe started with a big bang and black holes but I also entertain my push Univers which I favour simply because it makes more sence to me... If the push idea was mine and I was the very first to think of it I would as a duty to mankind do more..maybe.. but the idea is out there and thats all I need to feel any duty to humanity is discharged...

as to poineer I have been specific..they will in time appear to stop and then race away at a speed the same as the one we travel thru the galaxy... when will they appear to stop??? well lets say it will be a long time after we are all dead and I am not hanging around till then...so what joy will I get if in 200 years whatever they appear to stop... I do get joy that what I predicted seems to be going that way... it is right(so far) it needs no math for such an observation to be a fact they are slowing and I guess if one took the time NASA could tell us how much and I guess that input may give us an indication of just how "sticky" space is ...

AND as to math..when Prof Hawking or any celebrity scientist makes comment they never do it standing in front of a white board writing the sums as they go... and the reason why they dont is no one cares ... I dont care what the math proves I dont buy the big bang or black holes or dark matter and I think it is presumptuois in the extreme for humans to hold up some sums and claim they have all the answers... how can we be so certain about what is out there and what happened 13 billion years ago... be realistic the theory goes from theory to fact without opposition because of the math support... math is helpful there is no doubt but if the premise is wrong what then..the presenter of the premise will not offer math that does not support it...
ANYways I had sworn to not talk about this stuff anymore..I have my views and those views will never gain respect from those who subscribe to a different view...but I have no problem with that...
Now science works by peer review of papers...a very comfortable environmet I feel..law works by extreme confrontation and adoption of an opposite position and one would think that would get the best result but it really comes down to one thing... it is not what is right that prevails it is the person who throws the most money to get a result that often decides matters of a "grey" nature...now give me as many physistis who support GR to direct at proving my case and I bet I will win...irrespective of the facts ... but if law sees such a corruption what corruption does peer review subject itself to... what peer review went into the theory of inflation, for example,... we have math but no observation at all ... inflation does not have the right to be called a theory..no predictions..well I have a prediction based on observation but I still am humble enough to call it an idea...

Dam it stop getting me going on things I like thinking about I have to fix a boat. Have a great day and sincerely thank you for the chats I love them.

alex

[xelasnave]

Bojan if you are still there I have taken the time to do some math and have actually worked out a way that I may be able to quantify the pressure and predict the rate at which the pioneer slow ..now wheter I can or not is another matter but I bet you will be proud of my effort ... and I thank you for your chalege to do this as for whatever reason my mind seems to have taken it on and yesterday I saw how it could be done. I was lucky to be able to sit for 5 hours and just think it thru and I think I can provide a simple formulea to express a range of probable pressures and from that range determine at rate the pioneer may slow... anyways I have taken your advice it seems.
I am the road so it will be a while before I can post it on the gravity push site. Also I hate to say this but I have completly changed my mind on black holes ...
alex

[Robh]

Your comment didn't go unnoticed!
Regards, Rob

[bojan]

Alex, I am proud of you :-) (because of your persistence)
And I will certainly have a look at your work. Just be reminded, this principle must be applicable to other things.. and if because of it the planetary orbits can not last more than couples of hundred of years (and we KNOW they are stable for billions of years, your theory goes down the tube.
C'est la vie.. :-)

[xelasnave]

The idea of what may pass thru a point in space presents one with the prospect that even at the smallest point one can imagine it must be witness to everthing in the rest of the universe..which is what I have been saying to a degree ..but how complex things are even at a single point... how can such a situation be described via math... so we must look for a generalisation that shows the general drift of things..anyways Hersel had an imaginary sphere to work out the Sun's energy..primative but competant..so I thought why not do similar for a single point ..but in the vain of what may reach it... now this is rather a wide range but we will have to see there is absolutly no pressure from without or there is something...
I have not thought about these matters for a week but will thi9nk more when I can...

alex