CraigD Posted August 12, 2012 Report Posted August 12, 2012 We should doubt that a SMBH (Super-massive Black Hole) has any on/off switch, and gas is hardly to be blown away from the center An upward-pointing electric field in that region would deliver electrons down the rotational axis of the accretion disk and they would repel each other away along that axis, but that isn't gas.The "on/off switch" is somewhat simple than maybe I implied. On is when there is matter to fall in towards the center. Off is when there is not.There was a discussion of nearly this same subject a few years ago, in posts in an idiosyncratic alternative cosmology thread, such as this question postBlowing and Bubble Theory Yes, I know of this scenario. The problem with this hypothesis is that it raises more questions than it superficially answers. In this model to explain the paradoxical positioning of the AGN (in the area of the galaxy with the most food for it to eat) yet the contradictory-appearing fact that it is not eating. The problem with this particular model is that if you really look at it, it supplies two “whats” but conveys no “hows” or “whys.” Here’s my meaning, the “whats”:1: What event happened to stop the AGN’s eating—a blowing of material (dust & whatnot) away from the AGN.2: What stopped future eating to occur—a bubble, which pushes out and then back in, but not really all the way in.…and several following answer posts, among them this one and this one, by me. I encourage you, Heedless, to read this section of this old thread, and this even older (2007) one, which has some similar discussion. In both these, I cite an Oct 2005 Scientific American article, Françoise Combes’s Ripples in a Galactic Pond, which remains the best description of the dynamics of galaxies I’ve yet read, and which I highly recommend. Summarizing previous discussion, the prevailing consensus among people experienced in the complicated dynamics of galaxies rests on a few key points (I've bolded the parts directly addressing Heedless's doubts/questions/concerns):Nearly all galaxies have supermassive black holes at their centers (nuclei)These galactic nuclei experience periods in which greater amounts of matter fall into them, are heated in the SMBH’s accretion disk, and produce great amounts of radiation, exceeding the combined luminosity of all the stars in the galaxy, and dramatic large structures such as plasma jets. In this state, the nucleus is called “active”These nuclei also experience longer, “quiet” period in which little matter falls into them. Our own galaxy is in one of these now.On a slightly more detailed level, another key pointMost of the infalling matter isn’t stars and other large bodies, but dust and gas.This detail is important, because it’s key to the conventional explanation for the active/inactive galactic nucleus “on/off switch”. AGNs produce a lot of radiation, both light and stream of particles. Although the force exerted by this radiation on distant stars and other large bodies is negligibly small, its effect on tiny bodies such as gas molecules and dust is great, reversing their direction from inward, toward the AGN, and resulting in a nearly empty “bubble” around the AGN, “starving” it, and causing it to become inactive, or quiet. These “shock waves” of radiation pressure driven dust and gas are not only key in explaining the AGN on/off switch, but believed to be important in triggering the formation of solar systems from protostellar dust/gas clouds – but this is a whole other subject, which I don’t want to raise now, distracting from the on/off switch discussion. You can think of the paths of this dust and gas as a radial in-out “breathing”, or, in classical orbital mechanical terms, consider each dust grain and molecule to follow very high eccentricity elliptical orbits that result in their eventual collision with the hot accretion disk of a future AGN. I am not sure you using "physics" at all from the comment above. I do not understand what you are driving at... :eek_big: Gravity is the force that defines the object as a Black Hole. It would not be "black" without it. The more you say shows how little you know.AD hominem attacks tell me that there is nothing I can or want to do to help you.Heedless, I think you’re justified in being repelled maddog’s disparaging of your knowledge of basic physics and astrophysics. However, in maddog’s defense, you do appear unfamiliar with the astrophysics known to regular readers of popular science periodicals, like Scientific American. I hope you find the above references and summary explanations helpful, either as an introduction to or reminder of current mainstream astrophysics, which isn’t outside of the realm of simple applied physics, but due to the great number of bodies involved, more complicated than usual. I’d really like everyone involved in discussions like these threads to understand the relevant mainstream scientific consensus. Quote
maddog Posted August 13, 2012 Author Report Posted August 13, 2012 AD hominem attacks tell me that there is nothing I can or want to do to help you.I am not sure I understand this either. My earlier statement was not meant as an aspersion on your ability to understand, possibly on your "apparent" lack of knowledge of the subject matter. Now as for CraigD's excellent summary (I will have to go and refresh my memory on your links myself), I think will be sufficient background to understandwhat I meant when I started this thread about the latest SciAm article. maddog Quote
Village Idiot Posted August 14, 2012 Report Posted August 14, 2012 ... you do appear unfamiliar with the astrophysics known to regular readers of popular science periodicals, like Scientific American. You got that right. SciAm stole my gullibility away the October day within this decade when they published a forecast for hurricane control: Oil the ocean to retard release of ocean heat, mandate selective agriculture to regulate insolation, enforce stipulated rerouting of air traffic to present strategic presentation of contrails to deflect solar radiation, and loft orbiting microwave beams controlled to burn hurricane center-walls to afford steering control over hurricanes away from preferential folks on the ground. It was written by a full-fledged meteorologist. Tears of laughter! But all of that aside, my very recent beginning of interest in astrophysics and meteorology came upon my realization of drastic oversight of a fundamental factor of galactic infrastructure. Involvement was not as a researcher but, in the pitch dark, by means of mental experimentation. I hope you find the above references and summary explanations helpful, either as an introduction to or reminder of current mainstream astrophysics, which isn’t outside of the realm of simple applied physics, but due to the great number of bodies involved, more complicated than usual. I’d really like everyone involved in discussions like these threads to understand the relevant mainstream scientific consensus. (My bold-facing above.) In all humility, I am here because of my discovery of the irrelevance of the mainstream scientific consensus. I fear that from here I must go because of my consequential lack of indulgence for the mainstream and my ignorance of its jargonese. All I seek is a forum where I can present the simplicity that supplants the convoluted complexity mankind enforces due to her being so oblivious to the counter-intuitive phenomena of stable macroscopic formations of electrostatic arrays. Maddog, I carry no burden of grudge, but suggest that what is ungentlemanly of ad hominem response is that it denies the victim means to defend himself in dealing with the issues. Until we meet again.Heedless, the Village Idiot. Quote
JMJones0424 Posted August 14, 2012 Report Posted August 14, 2012 If you can't be bothered to learn even the jargonese vocabulary with which the rest of us communicate, why then should we commit ourselves to deciphering your ramblings? Quote
Village Idiot Posted August 14, 2012 Report Posted August 14, 2012 If you can't be bothered to learn even the jargonese vocabulary with which the rest of us communicate, why then should we commit ourselves to deciphering your ramblings? No contest. Perhaps I was continuing to suppose the the term "On/Off Switch" to be mere jargon when I tried to explain my innocence of any attempts by scientists to explain how orbital phenomena fails to prevent matter from joining our SMBH. My inadvertent use of the "jargonese" word might seem as abusive to some of you as your use of the word "ramblings". Surely, Lena would say of me, "He brought in on himself Miss Tweedle". Nevertheless, it has already been pointed out for me by our host that I had blundered into an esoteric society while holding insufficient credentials to do so, and now understand that as the answer to your question. Forgive me as I will forgive you for not considering the validity of my solution to the technical issue at hand. Respectfully submittedHeedless, the Village Idiot Quote
maddog Posted August 14, 2012 Author Report Posted August 14, 2012 Maddog, I carry no burden of grudge, but suggest that what is ungentlemanly of ad hominem response is that it denies the victim means to defend himself in dealing with the issues. Until we meet again.Heedless, the Village Idiot.Ahh, using Latin on me eh - "argumentum ad hominem" - I flunked Latin in High School (even though I was raised Catholic). My Bad. So looking this up on Wiki I found a def... An ad hominem (Latin for "to the man"), short for argumentum ad hominem, is an attempt to negate the truth of a claim by pointing out a negative characteristic or belief of the person supporting it.[1] Ad hominem reasoning is normally described as a logical fallacy,[2][3][4] more precisely an informal fallacy and an irrelevance.[5] The link to the whole definition can be found at Ad hominem. Any fallacial logic on this subject might be that something other than gravity might be hold the moon at bay or to orbit the earth, especially an electric field. I do admit the similarity of the two equations. Both depend on an inverse square law. Both represent field between objects. However from General Relativity the mass of an object determine how the spacetime nearby is deformed to move an orbiting object around it, not a charge being moved by an electric field. In any case, no foul. I mean no animosity to you or anyone who comes to this forum for any reason. I do my best to understand all who post here. I do however take people at there word, so if anyone says not what they mean. This can lead to confusion. I don't make my comment towards you in particular, just in general. There has been discussion here where due misunderstanding on someone's part (mine or anyone), a discussion can go awry. maddog Quote
maddog Posted August 15, 2012 Author Report Posted August 15, 2012 No contest. Perhaps I was continuing to suppose the the term "On/Off Switch" to be mere jargon when I tried to explain my innocence of any attempts by scientists to explain how orbital phenomena fails to prevent matter from joining our SMBH.This phrase above in bold is a convention I made (invented) or borrowed from the article (I don't remember) that refers to the presence or absence of nearby matter to fall in. It is symbolic, not a real "switch" or physical mechanism. Nevertheless, it has already been pointed out for me by our host that I had blundered into an esoteric society while holding insufficient credentials to do so, and now understand that as the answer to your question.Maybe this forum can be seen as an eclectic group of individualists who espouse "jargon" in conveyance of discussion on a topic. I will go along with the 'eclectic' part. Jargon is only so for the uninitiated (those that don't know it). In this case to have an open mind while engaging in the discussion will grant that newly visiting individual an opening to present an alternate view. To pronounce an alternate view as a fact or some alternate theory about how it "really" is (even to suggest such) and this eclectic cadre will likely demand some modicum of "Proof" or some corroborating evidence. It is only natural. maddog Quote
Village Idiot Posted August 18, 2012 Report Posted August 18, 2012 I am not sure you using "physics" at all from the comment above. I do not understand what you are driving at... :eek_big:I am here for those who might understand, or will meet me halfway by attempting to do so. Gravity is the force that defines the object as a Black Hole. It would not be "black" without it. The more you say shows how little you know. I do not understand what you are driving at. What color would a black hole be if it were not somehow for gravity? I know that it makes uphill too steep for light to travel out of the event horizon, but my concern is to clarify how stuff gets stuffed into and event horizon to begin with. Can you share your insight into my limitations? Explain a thing I said that reveals my ignorance of what specific information. (There is so much that I do not know that your statement hides the needle in a haystack.) Your first sentence would be correct. The orbit would define the accretion disk. From the rest, I can see you don't understand Newtons Law at all. maddog Again, I ask that you elucidate. In the autumn, I don't sit under the apple tree (if you mean Newton's Law.) By the way, I can vouch for more more moons than I said: 1054 of them although I paid little attention early on. This might be telling my age. Quote
CraigD Posted August 18, 2012 Report Posted August 18, 2012 ... but my concern is to clarify how stuff gets stuffed into and event horizon to begin with. Can you share your insight into my limitations?Astrophysicists believe that stuff gets into the spheroidal volume defined by a black hole’s event horizon as follows:A sufficiently massive star (about 25 Solar masses) fuses all of its available light elements (one with atomic masses less than iron), and ceases to emit photons and other radiationWithout radiation pressure to support its outer layers, the star contracts, producing elements heavier than iron, and briefly producing very powerful radiationThis radiation propels most (80%+) of the star’s mass outward in a supernova explosionthe remaining mass is propelled inward into a volume less than the event horizon defined by its mass and angular momentum, becoming a stellar mass black hole.The minimum mass of a newly-formed stellar black hole is theorized to be between 1.7 and 2.7 solar masses, the maximum, about 16. The least massive black hole yet observed is believed to have a mass of about 3.8 solar masses. The stellar black hole may increase mass after its initial, violent formation, by a more gradual accretion of infalling matter, which may consists primarily of the original star’s expelled matter, or the matter of a companion star. Black holes with large, hot disks of accreted and jets of expelled material around them, from either source, produce a lot photon radiation, usually in the X-ray range. The first X-ray source widely accepted to be due to the accretion disk of a stellar black hole, Cygnus X-1, discovered in 1964, appears to include a black hole of about 15 solar masses “feeding” in this way on matter from its companion star, blue supergiant star with mass 20-40 solar masses. And there’s a Rush song about it ;) Quote
Village Idiot Posted August 19, 2012 Report Posted August 19, 2012 Thanks for the snapshot of a black hole's early life. My goof was to use the term "... in the first place". No harm, since it brought me an answer to a question I could not have known to ask. The question I meant to pose was one I think to have an answer. It pertains to the delivery of matter to an established SMBH laid back in the center of a galaxy such as ours. Beyond the central bulge, where we might presume galactic matter orbits the SMBH, it would seem that any matter getting close to the bulge has become subject to joining the black hole. The mere mass of the SMBH suggests that it has been quite successful in gaining mass. Being dubious about mass sliding off from poles of orbs prevents my confidence in consensual lore where polar jets are concerned. I doubt convoluted stories where my own logic leaves me no mysteries. Hence, my existing reason for belief that the accretion disk for a SMBH is always growing supplants my query on how orbiting matter becomes engulfed within the "disk". It is intercepted by a continuously growing galactic central bulge. One might wonder it will ever stop while anything is left. Holding that our star-filled portion of our galaxy has a downward-pointing electric field, then from a disk of some fifty thousand light years' radiusmore or less, comes protons and any other particles bearing positive charge. Protons would heap up as a hollow bubble, attaining altitude from the center by electrostatic repulsion rather than orbital velocity. That hollow form would resist passage of orbital particles, and neutron-bearing particles sagging below would continue the resistance to passage for neutral matter thus doomed to reach the center. Thus, as the galaxy grew, nothing halted that process, and rotation of the positively charged accretion disk accounts for the magnetism around the SMBH. The bounds of that central bulge/accretion disk define an upward-pointing electric field that would rip electrons from neutral matter and send them down to the rotational axis of that bulge instead of to the electron-glutted SMBH. Quote
Ti@NiS Posted August 21, 2012 Report Posted August 21, 2012 If a black hole is a compact object as the beginning of the universe, as it is said that light can not escape? if the universe had no light in the beginning? only many millions of years later? Black holes are compacted in space time, yes? Light traveling in space time is stretched out of sight and out of our instruments. Then inside a black hole can not exist radiation of any kind because the space time been stretched out of control, yes? Quote
Ti@NiS Posted August 21, 2012 Report Posted August 21, 2012 How a photon can stretch before disappearing? Quote
Moontanman Posted August 21, 2012 Report Posted August 21, 2012 If a black hole is a compact object as the beginning of the universe, as it is said that light can not escape? if the universe had no light in the beginning? only many millions of years later? A black hole is not the same as the beginning of the universe. At the beginning of the universe the universe was too dense to allow the transmission of light. Black holes are compacted in space time, yes? They are contained within space time. Light traveling in space time is stretched out of sight and out of our instruments. Then inside a black hole can not exist radiation of any kind because the space time been stretched out of control, yes? No, there is thought to be a layer where light actually orbits around the center of mass of the black hole. Quote
Moontanman Posted August 21, 2012 Report Posted August 21, 2012 How a photon can stretch before disappearing? As far as I know photons do not stretch, their wave length does... Quote
Ti@NiS Posted August 21, 2012 Report Posted August 21, 2012 hello moontanman yes, black holes are considered conditions same as beginning of universe. Singularity at center for two of them, yes? No space time for black holes anymore. Outside of it, no? Quote
Ti@NiS Posted August 21, 2012 Report Posted August 21, 2012 Photon wave stretched beyond detectable size? Quote
Moontanman Posted August 21, 2012 Report Posted August 21, 2012 hello moontanman yes, black holes are considered conditions same as beginning of universe. Singularity at center for two of them, yes? No, it is not known what is at the center of a black hole, our understanding of the center breaks down before the singularity is reached. The idea of a singularity is an abstract that probably does not and cannot exist. No space time for black holes anymore. Outside of it, no? no, there is space and time inside a black hole's event horizon. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.