One of the subjects I have been most interested since high schools is the subject of black holes and their link to jets being emitted from the center of galaxies. These galaxies are often called Seyfert Galaxies, that is, galaxies with an active nucleus. Their center registers a very high amount of energy which is linked to these jets. Here are several examples:
Galaxy 0313-192. Credit: W. Keel (Univ. Alabama), m. Ledlow (Gemini Obs.), F. Owen (NRAO), AUI, NSF, NASA
The red stuff you see in the picture is the jet of gas being emitted from the center of the galaxy. Here are some galaxies that have similar jets.
It is interesting to find that the same happens to quasars (quasi-stellar radio sources). These are compact objects of one light year across that have a very high redshift. There are currently two positions regarding quasars. The first, the conventional one, states that because of the Hubble Law and their extreme redshift, these are the most distant and perhaps oldest objects in the universe. According to the conventional view, quasars are nothing more than gas that surrounds a supermassive black hole. The other position (a very controversial one) suggested by Halton Arp, is that quasars are proto-galaxies ejected from the center of Seyfert galaxies, since they always seem to be populated around Seyfert galaxies. Even when the former position is the most accepted, there is overwhelming evidence for the latter, especially after the discovery of a quasar in front of a Seyfert Galaxy.
Credit: López-Corredoira and Gutiérrez See article about it in: Pasquale Galianni, E. M. Burbidge, Halton C. Arp, V. Junkkarinen, Geoffrey Burbidge, and Stefano Zibetti. "The Discovery of a High Redshift X-Ray Emitting QSO Very Close to the Nucleus of NGC 7319"
Galaxy 0313-192. Credit: W. Keel (Univ. Alabama), m. Ledlow (Gemini Obs.), F. Owen (NRAO), AUI, NSF, NASA
The red stuff you see in the picture is the jet of gas being emitted from the center of the galaxy. Here are some galaxies that have similar jets.
Cygnus A
Credit: C. Carilli
Centaurus A
Credit: Mhardcastle
M87
Credit: NASA
Credit: C. Carilli
Centaurus A
Credit: Mhardcastle
M87
Credit: NASA
It is interesting to find that the same happens to quasars (quasi-stellar radio sources). These are compact objects of one light year across that have a very high redshift. There are currently two positions regarding quasars. The first, the conventional one, states that because of the Hubble Law and their extreme redshift, these are the most distant and perhaps oldest objects in the universe. According to the conventional view, quasars are nothing more than gas that surrounds a supermassive black hole. The other position (a very controversial one) suggested by Halton Arp, is that quasars are proto-galaxies ejected from the center of Seyfert galaxies, since they always seem to be populated around Seyfert galaxies. Even when the former position is the most accepted, there is overwhelming evidence for the latter, especially after the discovery of a quasar in front of a Seyfert Galaxy.
Credit: López-Corredoira and Gutiérrez
Here are examples of quasars emitting radio-jets:
Quasar 3C175
Credit: Alan bridle (NRAO Charlottesville)VLA, NRAO, NSF
Quasar 3C31
Credit: Alan bridle (NRAO Charlottesville)VLA, NRAO, NSF
Credit: Alan bridle (NRAO Charlottesville)VLA, NRAO, NSF
Quasar 3C31
Credit: Alan bridle (NRAO Charlottesville)VLA, NRAO, NSF
The Conventional View: Black Holes
It is always very strange to suggest black holes as the explanation for the emission jets by Seyfert galaxies. The reason why it is strange is that when one thinks of a black hole, we imagine this thing that sucks everything it finds, even light. However, jets are practically ejected, not sucked, by the galaxies' center.
The problem is that if one takes into account quantum mechanics we see that it is not that easy. Jets, according to the conventional view, are just the result of what is called "The Hawking radiation". If we imagine a black hole with gas surrounding it, according to Heisenberg's uncertainty principle, the particles in that gas can be ejected by these huge amounts of energy by this black hole. The particles of light or gravity (gravitons) are not particles properly speaking, but tiny packets of energy (discrete amounts of energy or quanta). As the intense gravitational force of the black hole sucks electrons, energy is released in pairs (positive and negative energies).
The negative energy particles can fall into the black hole and become real particles with mass, while the positive energy is being released from the black hole, and it could be that it takes the form of real particles too. So, it appears to an observer that such a huge amount of energy is released by a black hole. According to Einstein's equation E=mc², energy is proportional to the mass. So, when we have negative energy being sucked, the flow will reduce the black hole's mass. As a result, the black hole loses entropy, which is compensated for by the entropy of the radiation being ejected, so the second law of thermodynamics is never violated. The temperature of the black hole increases, and that makes it lose mass more quickly.
Unconventional Approaches
There are other explanations to what is going on in the center of Seyfert galaxies. One of them comes from the Quasi-Steady State Cosmology, the other from Plasma Cosmology.
A. Quasi-Steady State Model
To understand how a positive and negative energy are, remember only this: if you imagine a spring you pull apart, you will feel the force the spring exerts on your hands to attract each other. However, as you push the spring to its natural state, you will not feel the spring anymore. This is a positive energy. A positive energy, the force is reduced when two objects come closer. A negative energy force, like gravity, is just the opposite, the force increases as the two objects come close together. Einstein's General Relativity proposes that for every positive energy force (such as mass, electromagnetism or a spring) is present, then there should be a negative energy force (it creates a gravitational force due to the warping of space-time).
Fred Hoyle, who originally proposed the Steady State Theory, and later favored the Quasi-Steady State, and Jayant Narlikar, made a fusion between Einstein's General Theory of Relativity and Mach's principle. Mach's Principle states that all matter in the universe is connected somehow ... in other words, the inertia of every particle in the universe derives from the inertia of all other particles in the universe, a kind of action at a distance.
When you have an object like a Seyfert Galaxy, with a high energy concentration, there is probably a negative energy field in which diffuse matter accumulates within the nucleus and once enough matter is accumulated, its gravitational force blows it to pieces. In that process, new matter is ejected. According to those who favor the Quasi-Steady State Cosmology, the right mechanism of negative energy force would be a white hole or a supermassive black hole. We see, for instance, stuff coming out of galaxies, like plasma jets or quasars.
According to Halton C. Arp, when we look at this Quasi-Steady State hypothesis, we can explain the high redshifts quasars have. For example, electrons' mass will have a mass that, following Mach's Principle, will depend on how much of the universe it has interacted with. Newly created particles within a Seyfert galaxy would have not interacted much with the universe, so its mass would be near zero. This will also happen to newly created electrons in a proto-quasar and moving out its parent galaxy. As the electrons interact with each other, they will gain mass, and eventually create a coherent object, a quasar. Young electrons, when ionized, would emit a photon which would manifest a lower energy rate, and as a result, it would appear more redshifted.
As quasars mature into galaxies, the electrons gain more mass until the redshift is reduced. Hence, contrary to conventional cosmology, which follows the Hubble Law, the redshift of galaxies have nothing to do with distance, but with age. The younger the ejected body from the galaxy, the higher the redshift, the older it is, the lesser the redshift. This is what is called the Variable Mass Hypothesis formulated by Jayant Narlikar and Halton C. Arp.
B. Plasma Cosmology Model
Plasma Cosmology also proposes a model to explain these radio jets in galaxies and quasars .... and stars.
According to Plasma Cosmology, space within the universe is not empty, but it is filled with plasma, a gas of electrically charged particles and dust. One characteristic of plasma is that it conducts electricity. Whenever electrons move, they also create a magnetic field. As a result, plasma has the tendency to filament, creating long gaseous "cables" that conduct electricity. Because of the magnetic fields they produce, they are attracted to each other (the Pinch Effect).
Jets of radiation and X-rays, which are detected from Seyfert galaxies and quasars are very well known in plasmas. For example, there is a device called plasma focus which is able to generate a filament similar to radio jets and X-rays. Here is an illustration.
Essentially it is composed of two cylinders, one inside the other and the space between them is full of plasma. When an electrical discharge occurs from the outer cylinder to the inner electrode, it travels to the end of both electrodes. Since it is filled with plasma, the plasma will quickly filament and twist itself inside the inner electrode. Instantly a plasmoid, a coherent plasma structure is created, and in the process of its annihilation two rays are emitted in opposite directions. Here is an animated version of the whole process:
The rays are essentially ions of electrons and positive charged nuclei. This same process, plasma cosmologists say, is what we see in the sky. First, we must see that conventional cosmologists only consider gravity as being the one force that can explain how cosmic objects form (stars, galaxies, clusters and superclusters). However, in order to explain these structures, generally they have to suppose the existence of invisible objects such as dark matter, dark energy, wrinkles in space-time, black holes among other entities. Plasma cosmologists, however, argue that if we suppose that the universe is dominated by electromagnetism and not just gravity, we will be able to explain a lot better (and without exotic entities) the structures we see in space.
Today scientists accept what Hannes Alfvén's theory of the formation of the Solar System in which electromagnetism plays a major role in the formation of the Sun and the planets. During the process of the formation of the Solar System, inevitably we see not only a faster and easier way the primordial cloud formed into planets and the Sun, but also electromagnetism is the only explanation of how the Sun could have transfered almost all its angular momentum to the rest of the planets (especially Jupiter and Saturn). Gravitation alone cannot do this.
Alfvén and other proponents of plasma cosmologists have also made some simulations that correspond exactly to what we see in the universe. Scientists in the twentieth century had more or less a theory on how the galaxies are formed, but they did have serious problems explaining why galaxies have "arms". A possible explanation can be seen, for instance, if we suppose clouds of plasma that twist themselves depending on their electrical charge. They are attracted to each other and start spinning around until they form a structure of a galaxy. This phenomenon has been seen in lab when scientists work with plasma, and plasma cosmologists suppose the same phenomenon happens in space. Anthony Peratt created a simulation of what happens if we take into account of electromagnetic energy (not gravity) of two gigantic clouds of plasma in space. See for yourselves:
Clusters and superclusters can also be explained with plasma. Since electromagnetism dominates the universe, we see a filamentary structure of superclusters with big empty areas of space. Today, traditional cosmologists explain this as a manifestation of space-time ripples and dark matter. However, plasma cosmology needs no such exotic explanation: if space is filled with plasma, and electromagnetism dominates in a cosmic level, we should see the cosmos as being filamentary.
With respect to galactic jets, one of the things that Anthony Peratt simulations reveal is that these simulations also correspond very closely to what we see in space. Peratt made this illustration comparing his simulations with actual observations:
Plasma cosmologists explain these radio jets the following way:
1. Galaxies, like all other filaments in the cosmos, form electrical and magnetic currents that travel along the galatic arms along the plane of the galaxy to its center. It would pinch plasma in the galactic core accumulating energy. Gravity draws all of this matter to the galactic center accumulating about 10 to the 57th power ergs.
2. The energy is released upwards along the axis of the galaxy and flows again to the arms of the galaxy. When this energy is released upward along the axis of the galaxies, plasma jets are released to space. Simulations also predict that this energy can also be released downwards, and can create two different radio jets.
In the case of quasars we have in the Dense Plasma Focus a perfect model for it. A quasar, like a Dense Plasma Focus, are dense forms of energy which differ only in scale, but the dynamics are very similar. Superclusters, because of the flow of electromagnetic currents, form clusters within them, clusters form galaxies, and galaxies form stars. The reason for this is that plasma flows always form substructures within it. As proto-galaxies form due to electromagnetic circuits we have described above, these galaxies form plasmoids (about 200 light years across) in the center of these protogalaxies. in the inner part of the plasmoid we will see an electromagnetic field along its axis, accelerating beams of protons and electrons. The small region from which these beams emerge from are actual quasars, about one light year across.
No black holes are needed to explain these jets. A confirmation of this entire process is the Herbig-Haro Objects, proto-stars that undergo exactly the same process. Of course, conventional cosmologists cannot use the "black hole" argument with Herbig-Haro objects, protostars surrounded by a plasma disk that emit radio jets. Here is one example:
Reflections
One big problem that we face with traditional cosmology with the black hole explanation for radio jets is the strong evidence of the correlation between Seyfert galaxies and quasars. It is based, in part, on the assumption of the Hubble Law, that the velocity of objects away from the Earth is correlated with their distance, and that the universe is expanding. As a result, they get to the erroneous conclusion that quasars in reality are not near Seyfert galaxies, but are, instead very far away.
Another problem with conventional cosmology is that, with the black hole explanation, it can explain the radio jets in galaxies and quasars, but is unable to apply the same theory to other objects that emit radio jets, such as the Herbig Haro objects.
The Quasi-Steady State model, on the other hand, does not accept the Hubble Law as a strict law in cosmology. Instead it relates redshift with age, not with velocity. It does provide a very neat explanation of how quasars are created within galaxies and why do they have a very high redshift. Since the center of galaxies are the place where creation is taking place, and newly created particles have not interacted enough with other particles, the light they emit show a high redshift. Plasma jets are the result of very powerful forces such an intense presence of negative energy interacting with matter. However, this proposal, even when is less exotic, it still cannot explain how structures such as the Herbig-Haro objects emit plasma jets. Also, the "variable mass" proposal seems to violate the laws of conservation of mass and energy. Even though they claim it does not, because the presence of matter is presupposed in this model, there is a creation of matter in the universe, so mass always increases depending on the inertia of the rest of the mass of the universe.
Plasma cosmology has the advantage that with one theory can explain most of the structures in the universe without the need of exotic objects such as black holes, dark matter, dark energy, and the like. It is does not advocate variable mass either. The fact that it can explain the presence of radio-jets in quasars, galaxies, and Herbig-Haro objects with one theory is a considerable advantage. The history of science shows that the more phenomena is explained by one theory, the better it is (think of Newton's theory of gravity). It seems that plasma cosmologists also recognize the importance of pointing out the strong relationship between quasars and Seyfert galaxies. Anthony Peratt, however, has expressed misgivings regarding the possibility that quasars are actually ejected from the center of galaxies, even though he does recognize the quasar-galaxy relationship. Peratt and Alfvén do think, however, that quasars are formed in place by Birkeland currents in these galaxies. On the other hand, Donald E. Scott, in his book The Electric Sky seems to endorse Halton Arp's explanation of quasars. However, plasma cosmology has the disadvantage of not being able to explain quasars' high redshifts.
Each model has its advantages and its defects. It seems to me plasma cosmologists have the best theory about radio jets due to its explanatory power to explain phenomena. In the case of traditional cosmology, it seems that it does not have the explanatory power that alternative cosmologies have.
There are other explanations to what is going on in the center of Seyfert galaxies. One of them comes from the Quasi-Steady State Cosmology, the other from Plasma Cosmology.
A. Quasi-Steady State Model
To understand how a positive and negative energy are, remember only this: if you imagine a spring you pull apart, you will feel the force the spring exerts on your hands to attract each other. However, as you push the spring to its natural state, you will not feel the spring anymore. This is a positive energy. A positive energy, the force is reduced when two objects come closer. A negative energy force, like gravity, is just the opposite, the force increases as the two objects come close together. Einstein's General Relativity proposes that for every positive energy force (such as mass, electromagnetism or a spring) is present, then there should be a negative energy force (it creates a gravitational force due to the warping of space-time).
Fred Hoyle, who originally proposed the Steady State Theory, and later favored the Quasi-Steady State, and Jayant Narlikar, made a fusion between Einstein's General Theory of Relativity and Mach's principle. Mach's Principle states that all matter in the universe is connected somehow ... in other words, the inertia of every particle in the universe derives from the inertia of all other particles in the universe, a kind of action at a distance.
When you have an object like a Seyfert Galaxy, with a high energy concentration, there is probably a negative energy field in which diffuse matter accumulates within the nucleus and once enough matter is accumulated, its gravitational force blows it to pieces. In that process, new matter is ejected. According to those who favor the Quasi-Steady State Cosmology, the right mechanism of negative energy force would be a white hole or a supermassive black hole. We see, for instance, stuff coming out of galaxies, like plasma jets or quasars.
According to Halton C. Arp, when we look at this Quasi-Steady State hypothesis, we can explain the high redshifts quasars have. For example, electrons' mass will have a mass that, following Mach's Principle, will depend on how much of the universe it has interacted with. Newly created particles within a Seyfert galaxy would have not interacted much with the universe, so its mass would be near zero. This will also happen to newly created electrons in a proto-quasar and moving out its parent galaxy. As the electrons interact with each other, they will gain mass, and eventually create a coherent object, a quasar. Young electrons, when ionized, would emit a photon which would manifest a lower energy rate, and as a result, it would appear more redshifted.
As quasars mature into galaxies, the electrons gain more mass until the redshift is reduced. Hence, contrary to conventional cosmology, which follows the Hubble Law, the redshift of galaxies have nothing to do with distance, but with age. The younger the ejected body from the galaxy, the higher the redshift, the older it is, the lesser the redshift. This is what is called the Variable Mass Hypothesis formulated by Jayant Narlikar and Halton C. Arp.
B. Plasma Cosmology Model
Plasma Cosmology also proposes a model to explain these radio jets in galaxies and quasars .... and stars.
According to Plasma Cosmology, space within the universe is not empty, but it is filled with plasma, a gas of electrically charged particles and dust. One characteristic of plasma is that it conducts electricity. Whenever electrons move, they also create a magnetic field. As a result, plasma has the tendency to filament, creating long gaseous "cables" that conduct electricity. Because of the magnetic fields they produce, they are attracted to each other (the Pinch Effect).
Jets of radiation and X-rays, which are detected from Seyfert galaxies and quasars are very well known in plasmas. For example, there is a device called plasma focus which is able to generate a filament similar to radio jets and X-rays. Here is an illustration.
Essentially it is composed of two cylinders, one inside the other and the space between them is full of plasma. When an electrical discharge occurs from the outer cylinder to the inner electrode, it travels to the end of both electrodes. Since it is filled with plasma, the plasma will quickly filament and twist itself inside the inner electrode. Instantly a plasmoid, a coherent plasma structure is created, and in the process of its annihilation two rays are emitted in opposite directions. Here is an animated version of the whole process:
The rays are essentially ions of electrons and positive charged nuclei. This same process, plasma cosmologists say, is what we see in the sky. First, we must see that conventional cosmologists only consider gravity as being the one force that can explain how cosmic objects form (stars, galaxies, clusters and superclusters). However, in order to explain these structures, generally they have to suppose the existence of invisible objects such as dark matter, dark energy, wrinkles in space-time, black holes among other entities. Plasma cosmologists, however, argue that if we suppose that the universe is dominated by electromagnetism and not just gravity, we will be able to explain a lot better (and without exotic entities) the structures we see in space.
Today scientists accept what Hannes Alfvén's theory of the formation of the Solar System in which electromagnetism plays a major role in the formation of the Sun and the planets. During the process of the formation of the Solar System, inevitably we see not only a faster and easier way the primordial cloud formed into planets and the Sun, but also electromagnetism is the only explanation of how the Sun could have transfered almost all its angular momentum to the rest of the planets (especially Jupiter and Saturn). Gravitation alone cannot do this.
Alfvén and other proponents of plasma cosmologists have also made some simulations that correspond exactly to what we see in the universe. Scientists in the twentieth century had more or less a theory on how the galaxies are formed, but they did have serious problems explaining why galaxies have "arms". A possible explanation can be seen, for instance, if we suppose clouds of plasma that twist themselves depending on their electrical charge. They are attracted to each other and start spinning around until they form a structure of a galaxy. This phenomenon has been seen in lab when scientists work with plasma, and plasma cosmologists suppose the same phenomenon happens in space. Anthony Peratt created a simulation of what happens if we take into account of electromagnetic energy (not gravity) of two gigantic clouds of plasma in space. See for yourselves:
Clusters and superclusters can also be explained with plasma. Since electromagnetism dominates the universe, we see a filamentary structure of superclusters with big empty areas of space. Today, traditional cosmologists explain this as a manifestation of space-time ripples and dark matter. However, plasma cosmology needs no such exotic explanation: if space is filled with plasma, and electromagnetism dominates in a cosmic level, we should see the cosmos as being filamentary.
With respect to galactic jets, one of the things that Anthony Peratt simulations reveal is that these simulations also correspond very closely to what we see in space. Peratt made this illustration comparing his simulations with actual observations:
Plasma cosmologists explain these radio jets the following way:
1. Galaxies, like all other filaments in the cosmos, form electrical and magnetic currents that travel along the galatic arms along the plane of the galaxy to its center. It would pinch plasma in the galactic core accumulating energy. Gravity draws all of this matter to the galactic center accumulating about 10 to the 57th power ergs.
2. The energy is released upwards along the axis of the galaxy and flows again to the arms of the galaxy. When this energy is released upward along the axis of the galaxies, plasma jets are released to space. Simulations also predict that this energy can also be released downwards, and can create two different radio jets.
In the case of quasars we have in the Dense Plasma Focus a perfect model for it. A quasar, like a Dense Plasma Focus, are dense forms of energy which differ only in scale, but the dynamics are very similar. Superclusters, because of the flow of electromagnetic currents, form clusters within them, clusters form galaxies, and galaxies form stars. The reason for this is that plasma flows always form substructures within it. As proto-galaxies form due to electromagnetic circuits we have described above, these galaxies form plasmoids (about 200 light years across) in the center of these protogalaxies. in the inner part of the plasmoid we will see an electromagnetic field along its axis, accelerating beams of protons and electrons. The small region from which these beams emerge from are actual quasars, about one light year across.
No black holes are needed to explain these jets. A confirmation of this entire process is the Herbig-Haro Objects, proto-stars that undergo exactly the same process. Of course, conventional cosmologists cannot use the "black hole" argument with Herbig-Haro objects, protostars surrounded by a plasma disk that emit radio jets. Here is one example:
Reflections
One big problem that we face with traditional cosmology with the black hole explanation for radio jets is the strong evidence of the correlation between Seyfert galaxies and quasars. It is based, in part, on the assumption of the Hubble Law, that the velocity of objects away from the Earth is correlated with their distance, and that the universe is expanding. As a result, they get to the erroneous conclusion that quasars in reality are not near Seyfert galaxies, but are, instead very far away.
Another problem with conventional cosmology is that, with the black hole explanation, it can explain the radio jets in galaxies and quasars, but is unable to apply the same theory to other objects that emit radio jets, such as the Herbig Haro objects.
The Quasi-Steady State model, on the other hand, does not accept the Hubble Law as a strict law in cosmology. Instead it relates redshift with age, not with velocity. It does provide a very neat explanation of how quasars are created within galaxies and why do they have a very high redshift. Since the center of galaxies are the place where creation is taking place, and newly created particles have not interacted enough with other particles, the light they emit show a high redshift. Plasma jets are the result of very powerful forces such an intense presence of negative energy interacting with matter. However, this proposal, even when is less exotic, it still cannot explain how structures such as the Herbig-Haro objects emit plasma jets. Also, the "variable mass" proposal seems to violate the laws of conservation of mass and energy. Even though they claim it does not, because the presence of matter is presupposed in this model, there is a creation of matter in the universe, so mass always increases depending on the inertia of the rest of the mass of the universe.
Plasma cosmology has the advantage that with one theory can explain most of the structures in the universe without the need of exotic objects such as black holes, dark matter, dark energy, and the like. It is does not advocate variable mass either. The fact that it can explain the presence of radio-jets in quasars, galaxies, and Herbig-Haro objects with one theory is a considerable advantage. The history of science shows that the more phenomena is explained by one theory, the better it is (think of Newton's theory of gravity). It seems that plasma cosmologists also recognize the importance of pointing out the strong relationship between quasars and Seyfert galaxies. Anthony Peratt, however, has expressed misgivings regarding the possibility that quasars are actually ejected from the center of galaxies, even though he does recognize the quasar-galaxy relationship. Peratt and Alfvén do think, however, that quasars are formed in place by Birkeland currents in these galaxies. On the other hand, Donald E. Scott, in his book The Electric Sky seems to endorse Halton Arp's explanation of quasars. However, plasma cosmology has the disadvantage of not being able to explain quasars' high redshifts.
Each model has its advantages and its defects. It seems to me plasma cosmologists have the best theory about radio jets due to its explanatory power to explain phenomena. In the case of traditional cosmology, it seems that it does not have the explanatory power that alternative cosmologies have.
0 comments:
Post a Comment