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Jets Big and Small

  1. Jan 11, 2009 #1

    Jets Big and Small maybe the key to understanding the universe.

    On a side issue from the Quasars and cosmology post, since the file is locked.

    Response to Neried

    I understand your logic, your good.
    But! You said

    I'm quite awear of the huge and upto date papers on quasars, so called black holes, degenerate matter, jet formation etc. As for the unified AGN model, if History proves me write, unification is only temporary if that.

    As for Jets Big and Small

    Gamma-ray Burst 080319B: Evidence for Relativistic Turbulence, Not Internal Shocks

    Authors: Pawan Kumar, Ramesh Narayan
    (Submitted on 1 Dec 2008)

    The question that most ask is where and how does the jet form.

    The properties of jets are studied in depth and as time passes our abilty to study them in depth increases. Its fun and games for the next few years.
  2. jcsd
  3. Jan 12, 2009 #2


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    I'm not at all sure why you think jets "maybe the key to understanding the universe" Sundance.

    Surely they are, in the first instance, an astrophysics puzzle (not a cosmology one)?

    Also, while understanding jets in AGNs is indeed a most interesting research topic, I don't see how a detailed account of how they form could challenge the unified AGN model.

    Perhaps a mentor could move this thread to the Astrophysics section?
  4. Jan 13, 2009 #3
    Hello Neried

    Jets are part of the process that eject matter out.

    The interesting part is that it come out as degenerate matter mostly.

    Therefore forms part of a recycling process.

    There are varies mechanism for Jets, hre is one:

    Relativistic poynting jets

    The papers do not give the specific location of the formation of the jets
    and the trigger.
  5. Jan 13, 2009 #4
    most of the matter expelled by the jets is DEGENERATE?! I've never heard of that before. I'd love to read more about that.

    is it mostly metallic hydrogen?
  6. Jan 13, 2009 #5
    Hello Grandpa

    Read the link to understand jets.
  7. Jan 13, 2009 #6


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    (bold added)

    Interesting material, Sundance.

    Like granpa, I had never heard of the jets being degenerate matter, so I read the first paper you provided a link to, and skimmed several others. It seems that none of the papers mentions "degenerate matter".

    Would you please clarify?

    In particular, in which paper(s) did you read that the jets are composed (mostly) of degenerate matter?
  8. Jan 13, 2009 #7
    I'm not a 'Grandpa'. I'm just a 'granpa'. thats kinda the whole point of my handle.
  9. Jan 14, 2009 #8
    Hello Granpa

    Sorry for the "d"

    Neried I will get back to you.
    This is the link That I'm also reading.


    The transition of matter to compact matter that is found in black holes takes various transitions. Neutron matter maybe the first, followed by other exotic matter.


    Sorry for being quick, I will be back.
    Last edited: Jan 14, 2009
  10. Jan 14, 2009 #9

    This maybe of interest

    Transonic properties of the accretion disk around compact objects

    Authors: Banibrata Mukhopadhyay
    (Submitted on 13 Nov 2008)

  11. Jan 14, 2009 #10


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    Sundance, I am quite confused by all these references!

    Although I have not checked them all - not even read all the abstracts yet - there seems to be nothing in here of relevance to degenerate matter in jets, which is after all the topic of this thread.

    Can you please clarify?

    Yes, it is interesting ... but so are, in their own ways, the thousands of Astrophysics, General Relativity and Quantum Cosmology, High Energy Physics - Phenomenology, and High Energy Physics - Theory papers published every year.

    Would you please take some time, gather your thoughts, and write a succinct post on the area you are (apparently) interested in?
  12. Jan 15, 2009 #11
    G'day Neried

    Maybe this will help

    Accretion flow transonic

    Than again what do you think degenerate matter is?

    Transonic properties of the accretion disk around compact objects

    Authors: Banibrata Mukhopadhyay
    (Submitted on 13 Nov 2008)



    The X-ray Jets of Active Galaxies

    Authors: D.M. Worrall (University of Bristol)
    (Submitted on 17 Dec 2008)


    Dynamics of black holes

    Authors: Sean A. Hayward
    (Submitted on 6 Oct 2008)

    This process of forming jets will be the most important process to understand.

    It will explain the phase changes in star formation and the various forms of galaxy evolution.
  13. Jan 15, 2009 #12


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    Erm, the name is Nereid, if you please.

    What, may I ask, Sundance, do you think this may help with?

    I am still at a loss as to what you trying to say, in terms of jets, degenerate matter, and astrophysics.

    Can you clarify please? In your own words.

    In the material that you've provided links to, that I've read so far, three/four types of degenerate matter have been mentioned (if there are others, please identify them exactly):

    * electron degeneracy, as in white dwarf stars (below a thin atmosphere)

    * nuclear degeneracy, as in neutron stars (below a thin crust)

    * hypothetical degenerate states involving quarks or excited hadronic states (e.g. 'strange matter'), in the cores of neutron stars.

    * neutrino degeneracy, a hypothetical state of matter.

    AFAICS, no paper even hints at any of these states being found in jets!

    Why do you think this, if I may ask?

    AFAICS, none of the papers you've cited point to this conclusion.

    Besides, I don't know what you are referring to in "the phase changes in star formation"; could you elaborate please?
  14. Jan 16, 2009 #13
    Hello Nereid

    Am I do unstand that you do not understand star formation or jet formation and the probable formation of black holes from transient phase changes.

    As for degenerate matter it seems that you have partly covered its meaning and properties.

    As for phase changes in matter. Tell me what you think.

    Also explain to me what matter is found in jets.

    If I'm going to go into depth in this topic, I want to know what you know.

    I will have more time later.
  15. Jan 16, 2009 #14


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    The matter density of the bipolar jets observed in a range of astronomical objects, from YSOs (young stellar objects, the last stage of the collapse of the star's natal cloud) to AGNs, is extremely low, by our here-on-Earth standards ... a good vacuum to one so hard we can't make it in an Earthly lab!

    No degenerate states of matter are known for such low densities, esp when you also consider that the temperature of the matter in the jets (measured suitably) is high.

    The jets obviously contain electrons - that's what makes them visible, the synchrotron radiation - and protons; many jets also contain nuclei of heavier elements (than H), such as He.

    May I ask, again, from where you are getting the idea that jets contain degenerate matter?

    I've just replied to another one of your posts, from a month or so ago; it seems that you are conflating two quite different meanings of the term 'degenerate' that you have found in some papers ...
  16. Jan 17, 2009 #15

    What do you think the compact matter is made from?

    If its made from degenerate made?

    As we observe a Neutron star forming than evolving into ultra high density matter, that some call black holes.

    Than what do you think would be ejected from such compact matter?

    How are you reading these papers?

    Heres another

    Solitons and vortices in an evolving Bose-Einstein condensate

    Authors: Shi-Jie Yang, Quan-Sheng Wu, Shiping Feng, Yu-Chuan Wen, Yue Yu
    (Submitted on 6 Nov 2008)

    Keep reading

    Leptoquarks and Neutrino Masses at the LHC

    Authors: Pavel Fileviez Perez, Tao Han, Tong Li, Michael J. Ramsey-Musolf
    (Submitted on 22 Oct 2008)


    The SN 1987A Link to Others and Gamma-Ray Bursts

    Authors: John Middleditch
    (Submitted on 16 Aug 2007 (v1), last revised 6 Feb 2008 (this version, v8))

    This is quite interesting paper written 2001

    Induced Gravity in the Short Range

    Authors: C.P.Kouropoulos
    (Submitted on 13 Jul 2001 (v1), last revised 9 Aug 2001 (this version, v2))

    Abstract: We consider a pair of harmonic oscillators in two or three dimensions of space coupled by the standard electrodynamic forces : the Coulomb, the Lorentz and the electrokinetic forces. The addition of the Lorentz force is mainly felt in the short range and suppresses the radial correlated oscillating mode of such coupled oscillators. This imposes constraints on the system that make the two transverse modes degenerate. As a result, an 1/r antigravitational interaction now appears in the surviving anticorrelated radial zero-mode, which does not allow coherent states to form. As gravitation can only emerge from coherent modes, it can no longer be transitive. Matter in high densities would thus tend to increase its disorder, decouple from its own gravity, from the ordering far infrared Machian background that coheres its rest energy and would become intrinsically unstable. The highly energetic jets from galactic nuclei could be the consequence.
  17. Jan 20, 2009 #16
    Re: Origins of the Universe

    Hello all

    This is for Nereid

    Angular Energy Distribution of Collapsar-Jets

    Authors: Akira Mizuta, Miguel A. Aloy
    (Submitted on 28 Dec 2008)

    What makes people think that the universe had a start?

    A start from what?

    If there is an expansion in the universe, than why do the images show a clustering nature, such as Star cluster, galaxy unit, cluster of galaxies, super cluster of clusters of galaxies and so it goes on.

    Normal matter makes up about 4% and the rest can be called Plasma or degenerate matter that is found in compact objects such as Stars, Neutron stars excotic stars such as Quark and Neutrino and the so called black holes, stellar black holes and super massive ultra compact matter.
  18. Jan 21, 2009 #17
    Re: Origins of the Universe

    Hello Nereid

    It seems you read different papers than me on astropysics.

    Maybe you can refer me to the properties of jets from your reading and the different types of jets that are formed from various locations.

    and maybe what actually triggers the jets, and how the main jet keeps a stable position for millins of years.

    The main trigger for jets is a via a magnetic entanglement and when this happens degenerate matter is formed.
    Are you familiar with the process.
  19. Jan 21, 2009 #18

    Jonathan Scott

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    Re: Origins of the Universe

    You had better define what you mean by "degenerate matter" because it doesn't seem to match the usage which I've previously encountered.

    As far as I know, "degenerate matter" is conventionally used for various forms of non-atomic matter which normally only exists at abnormally high pressures, such as in neutron stars.

    However, if you simply mean that the matter which forms jets is presumably charged and very energetic and is therefore mostly totally ionized, consisting mainly of free protons and electrons which can subsequently recombine to form neutral hydrogen, then that would be quite plausible to me.
  20. Jan 21, 2009 #19
    I have a problem understanding the timings associated to GRBs.

    we know that hey can last for a "...typically a few seconds, but can range from a few milliseconds to several minutes, ..."
    and here (GRB_080319B)
    "The GRB's redshift was measured to be 0.937[5], which means that the explosion occurred about 7.5 billion (7.5×109) years ago...
    The emission in both curves then peaks at around 60 seconds before a long exponential decay...."

    It seems an extremelly short time for an event at the scale of the dimensions of a star and even worst for a galaxy.
    At such a distance, given the space expansion, what should be the period of time of the event at the moment of the occurrence, equivalent to actual the observed 60s ?
  21. Jan 22, 2009 #20

    Jonathan Scott

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    If something is happening at redshift z, we see it happening (1+z) times slower than it actually happens locally. In this case, 60s observed with a redshift 0.937 means 60s/1.937 locally, about 31s.
    Last edited: Jan 22, 2009
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