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Thread: Gravitational lensing or hot gas?

  1. #1 Gravitational lensing or hot gas? 
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    I was just looking at two papers, one on Atmospheric refraction and the other on the Hot gas halo around the Milkyway.

    If the gradient of gas density in our atmosphere is enough for us to see the sun, even when it is below the horizon, why wouldn't a galaxy's hot gas halo bend light?

    The gas halo of a distant galaxy would be thicker near the galaxy than further away, so when we look through it we should see a magnifed image of what is behind.

    If you assume the hot gas is in equilibrium with the galaxy, then the density gradient would follow the gravitational gradient, and it would produce Einstein's rings when viewed through, just as expected by gravitational lensing.
    (also applies it intercluster medium)

    How do we not know this effect is not more powerful than gravitational lensing?


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    I think a gas would manifest itself by the emission of thermal radiation, as well as scattering effects on the background light-source.


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    Quote Originally Posted by KJW View Post
    I think a gas would manifest itself by the emission of thermal radiation, as well as scattering effects on the background light-source.
    The gas is known to be there, at least for most galaxies.
    NASA - The Milky Way's Hot Gas Halo
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    Oh ok. So I was answering a different question from the one being asked? Sorry.
    There are no paradoxes in relativity, just people's misunderstandings of it.
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    For theorists confining themselves to the standard consensus model, gravitational lensing and observing bending of light from a distant star as it passes near the Sun, the phenomenon is considered either unanswerable or is answered by referring to Einsteinian general relativity with its magical view of space as being curved or bent in the vicinity of mass bodies. -For those like myself who subscribe to a universal ether view of the universe, gravitational lensing becomes a phenomenon involving etheric scale photonic transmission through space encountering varying energic cosmic settings. -When photonic energic units are near the distant star, they are under the influence of a very high stellar energic setting. These photonic units, which range from subatomic photons in size scale, down to elemental etheric units, then are transmitted through space via a process of instantaneous elemental-etheric resonance (photons do not "move" as "particles" through "empty space." What we now call the photon particle is really a particle-capacity unit composed of elemenatl etheric units.) As the photonic energic units transmit through outer space which is lower energy compared to the stellar region, via resonance the photonics acquire a lower energy setting themselves. As they once again arrive in the vicinity of a high energy solar region (our Sun) the photonics once again acquire a higher energy setting, which affects our observation of their "path through space" (which, again, in this ether model, is not really a particle's path through space but actually an instantaneous-resonance path primarily of elemental etheric units, with secondary visible subatomic photons). The "path" is seen to be curved because of the differential resonances between the high energy solar region and the less photonically energized region of space which the transmissions are continuously resonating with. -This model represents an alternative to general relativity to account for starlight beding near the Sun.
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    Quote Originally Posted by Michael Anteski View Post
    ...
    Please stop posting your ignorant pseudoscientific drivel.

    This model represents an alternative to general relativity to account for starlight beding near the Sun.
    If you think so, please feel free to show the mathematics of this model and how it predicts the observed results.
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  8. #7  
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    Quote Originally Posted by Michael Anteski View Post
    This model represents an alternative to general relativity to account for starlight bending near the Sun.
    Why does there need to be an alternative to general relativity? In a similar way that the earth's surface can be considered proven to be curved, spacetime can be considered more or less proven to be curved. My point is that the curvature of spacetime is a measurable quantity and not just some theoretical concept.
    There are no paradoxes in relativity, just people's misunderstandings of it.
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    Quote Originally Posted by KJW View Post
    Why does there need to be an alternative to general relativity? In a similar way that the earth's surface can be considered proven to be curved, spacetime can be considered more or less proven to be curved. My point is that the curvature of spacetime is a measurable quantity and not just some theoretical concept.
    Michael Anteski is a known crank, relativity denier, and proponent of classical aether. You can safely ignore him when it comes to discussing real science.
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    Quote Originally Posted by Markus Hanke View Post
    Michael Anteski is a known crank, relativity denier, and proponent of classical aether. You can safely ignore him when it comes to discussing real science.
    Yeah, I'm familiar with those. I suppose that because I'm still new to this forum, that I still feel motivated to try to point the ones here in the right direction, though experience from elsewhere does lead me to accept that this may be futile.
    There are no paradoxes in relativity, just people's misunderstandings of it.
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    Quote Originally Posted by KJW View Post
    Yeah, I'm familiar with those. I suppose that because I'm still new to this forum, that I still feel motivated to try to point the ones here in the right direction, though experience from elsewhere does lead me to accept that this may be futile.
    Yes indeed. The OP on the other hand is genuine, so his questions deserve to be addressed with proper science.
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    Quote Originally Posted by PetTastic View Post
    The gas halo of a distant galaxy would be thicker near the galaxy than further away, so when we look through it we should see a magnifed image of what is behind.
    A couple of points off the top of my head...

    Firstly, it would seem to be a remarkable coincidence if if the distribution of gas were to exactly match the predictions of gravitational lensing, for multiple galaxies.

    Secondly, if the bending of light were due to gas, then wouldn't we see absorption lines in the spectrum?

    And thirdly, there would be dispersion - light of different frequencies would be refracted by different amounts, which we definitely don't see.
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    Quote Originally Posted by Markus Hanke View Post
    Yes indeed. The OP on the other hand is genuine, so his questions deserve to be addressed with proper science.
    Agreed. However, this is not my area of expertise, so I can only suggest that the OP perform a dimensional analysis of the problem. When one considers the bending of light by the earth's atmosphere, then the refractive effect is overwhelmingly greater than any gravitational effect, and it would seem (without examining the problem in detail) that altering the density of the atmosphere isn't going to change the relative magnitudes of the two effects. However, by performing a dimensional analysis, one will get a clearer idea on the dependencies of the two effects, thereby providing at least a qualitative estimate of what conditions will cause one effect to overtake the other.
    There are no paradoxes in relativity, just people's misunderstandings of it.
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    Quote Originally Posted by KJW View Post

    Agreed. However, this is not my area of expertise, so I can only suggest that the OP perform a dimensional analysis of the problem. When one considers the bending of light by the earth's atmosphere, then the refractive effect is overwhelmingly greater than any gravitational effect, and it would seem (without examining the problem in detail) that altering the density of the atmosphere isn't going to change the relative magnitudes of the two effects. However, by performing a dimensional analysis, one will get a clearer idea on the dependencies of the two effects, thereby providing at least a qualitative estimate of what conditions will cause one effect to overtake the other.
    I think it can be shown in a rather general manner that refraction effects do not account for gravitational light deflection. Here's an example :

    Refractions on Relativity
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    Also, if gravitational light deflection was a refraction effect, then it should be frequency dependent; this obviously isn't the case.
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    Quote Originally Posted by Markus Hanke View Post
    I think it can be shown in a rather general manner that refraction effects do not account for gravitational light deflection.
    Whereas in my first post of this thread, I was assuming that the question was about confusing refraction and gravitational effects, in my subsequent post pertaining to the subject, I was assuming that there is no confusion between the two effects and that the question was simply about the relative magnitude.
    There are no paradoxes in relativity, just people's misunderstandings of it.
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  17. #16  
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    Do you think the OP is questioning the existence of gravitational lensing?
    There are no paradoxes in relativity, just people's misunderstandings of it.
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    Quote Originally Posted by KJW View Post
    Do you think the OP is questioning the existence of gravitational lensing?
    Actually, reading through this again, I am not really sure what the OP is asking, exactly. I thought initially that he thought gravitational lensing is explained by refraction ( thus denying GR ), but that doesn't seem to be the case.
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    I am suggesting that refraction by gas needs to be concidered, as a extra effect in parallel with gravitational lensing.

    The question is how powerfull an effect could it be, in comarison to gravitational lensing?

    Half of the evedence for dark matter comes from gravitational lenseing, if this effect is weaker than we thought, how much dark matter is out there?
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  20. #19  
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    Quote Originally Posted by PetTastic View Post
    I am suggesting that refraction by gas needs to be concidered, as a extra effect in parallel with gravitational lensing.

    The question is how powerfull an effect could it be, in comarison to gravitational lensing?

    Half of the evedence for dark matter comes from gravitational lenseing, if this effect is weaker than we thought, how much dark matter is out there?
    I would assume that refraction effects would be much stronger than gravitational lensing, but would also be quite distinguishable.
    There are no paradoxes in relativity, just people's misunderstandings of it.
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    Quote Originally Posted by PetTastic View Post
    Half of the evedence for dark matter comes from gravitational lenseing, if this effect is weaker than we thought, how much dark matter is out there?
    Gravitational lensing being of a different magnitude "than we thought" is tantamount to GR being wrong. There is currently no evidence that that is indeed the case.
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    Michael Anteski leave pseudoscience out of the mainstream subforums--consider this a mild warning.
    Thank you.


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    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by PetTastic View Post
    Half of the evedence for dark matter comes from gravitational lenseing, if this effect is weaker than we thought, how much dark matter is out there?
    Gravitational lensing being of a different magnitude "than we thought" is tantamount to GR being wrong. There is currently no evidence that that is indeed the case.
    No. It would mean the mass of the object bending the light it less than would be calculated purely from gravitational lensing, and in no way points to a problem with GR.
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  24. #23  
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    Quote Originally Posted by KJW View Post
    Quote Originally Posted by PetTastic View Post
    I am suggesting that refraction by gas needs to be concidered, as a extra effect in parallel with gravitational lensing.

    The question is how powerfull an effect could it be, in comarison to gravitational lensing?

    Half of the evedence for dark matter comes from gravitational lenseing, if this effect is weaker than we thought, how much dark matter is out there?
    I would assume that refraction effects would be much stronger than gravitational lensing, but would also be quite distinguishable.

    It does not look to be as easy to tell the difference between the two as I initially assumed.

    Refraction due to a density gradient is slightly different to what happens in a glass lens.
    If the gas halo gets denser near the galaxy bending the light, and also the rate of increase of density increases with gravity nearer the galaxy. Then gravitational lensing and this form of refraction look very similar. ie the light is bent more the near it passes to the galaxy.

    As guess dilute ionised hydrogen will have a refraction index very near 1.0, so I don't think you will see much croma dispersion. Possible the IR image will show tiny differences from the UV.
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  25. #24  
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    If light passes through a gas, then you are going to get scattering effects, as well as absorption spectral effects. Also, it is unlikely that the density variation with respect to position will match that associated with gravitation. Bear in mind that even in a constant gravitational field (and constant temperature), the density of a gas drops exponentially with height.
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    Quote Originally Posted by KJW View Post
    If light passes through a gas, then you are going to get scattering effects, as well as absorption spectral effects. Also, it is unlikely that the density variation with respect to position will match that associated with gravitation. Bear in mind that even in a constant gravitational field (and constant temperature), the density of a gas drops exponentially with height.
    The absorption and spectral effects have been detected. That is how we know the gas halo is there.

    The drop in density is the gradient I am referring to, but in this case gravitational field is spherical (GR approximating to inverse square in strength).
    Temperature gradient looks to be reversed ie cooler near the galaxy (I think).
    There is also the strong possibility the gas is not in stable equilibrium. That is the galaxy could be eating the gas and converting it to stars.

    ------- edit
    I think there is a good case for arguing a sutiable gradient in gas density should be there, but no direct evidence for it I can find so far.
    Last edited by PetTastic; August 9th, 2013 at 11:50 AM. Reason: Spell checjer pluggin does not like this site?
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    If the lensing effect was due to gas refraction, wouldn't we see spectral lines due to the gas?
    Its the way nature is!
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    I'd like to try to clarify something from my Aug. 9 Post. (I hope this does not count against me RE Lynx Fox's warning, because it is meant only to make that post clearer). -When I said that "space is not curved," I meant it in the sense that general relativity's "space" could be interpreted as a void, inasmuch as GR presumes there is no etheric medium in space, and I was trying to say that an empty void could "curve" only through magic. -However, that was not meant to say that curvatures do not exist in space. -My model of the ether is that it operates via instantaneous resonances between elemental etheric energic units, with simultaneous resonations occurring on up the size scale all the way to the cosmic level. -In that sense, GR's "curved space" is a reflection of a curvature mechanism all the way back to a yin-yang oscillational setting which immediately preceded the first elemental etheric energic units, with the primal units winding around due to their electro magnetic moments, which had a finite width, the result at larger and larger energic scales averaging out to a broader curvature pattern as we observe in the cosmos. -This attempt to clarify is not meant to get approval from my Forum critics, but to make the record clear as to the Aug. 9 Post.
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    Quote Originally Posted by AlexG View Post
    If the lensing effect was due to gas refraction, wouldn't we see spectral lines due to the gas?
    I thought we did see abortion lines from galaxy halos and the inter cluster medium, that is how we know it is there.

    Am I wrong on this
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    Quote Originally Posted by PetTastic View Post
    I thought we did see abortion lines from galaxy halos and the inter cluster medium, that is how we know it is there.
    Freudian Slip?
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    Quote Originally Posted by RedPanda View Post
    Quote Originally Posted by PetTastic View Post
    I thought we did see abortion lines from galaxy halos and the inter cluster medium, that is how we know it is there.
    Freudian Slip?
    Spell checker needs therapy
    RedPanda likes this.
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    Quote Originally Posted by PetTastic View Post
    Quote Originally Posted by AlexG View Post
    If the lensing effect was due to gas refraction, wouldn't we see spectral lines due to the gas?
    I thought we did see abortion lines from galaxy halos and the inter cluster medium, that is how we know it is there.

    Am I wrong on this
    We don't see absorbtion lines in the lensed light, other than the standard lines we see in any intergalactic light. The fact that there are no additional lines is one way we know that the light is not interacting electromagnetically.
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    Quote Originally Posted by Michael Anteski View Post
    I was trying to say that an empty void could "curve" only through magic.
    Don't be ridiculous. WHy don't you go and learn a tiny little bit about the theory you are criticising before writing such idiotic comments.

    My model of the ether is that it operates via instantaneous resonances between elemental etheric energic units, with simultaneous resonations occurring on up the size scale all the way to the cosmic level.
    You don't have a model.

    There is no such thing as "etheric energic units" or "simultaneous resonations". What is wrong with you?

    This attempt to clarify is not meant to get approval from my Forum critics, but to make the record clear as to the Aug. 9 Post.
    All you have made clear is that you are an ignorant crank.
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    Quote Originally Posted by Michael Anteski View Post
    I'd like to try to clarify something from my Aug. 9 Post. (I hope this does not count against me RE Lynx Fox's warning, because it is meant only to make that post clearer). -When I said that "space is not curved," I meant it in the sense that general relativity's "space" could be interpreted as a void, inasmuch as GR presumes there is no etheric medium in space, and I was trying to say that an empty void could "curve" only through magic. -However, that was not meant to say that curvatures do not exist in space. -My model of the ether is that it operates via instantaneous resonances between elemental etheric energic units, with simultaneous resonations occurring on up the size scale all the way to the cosmic level. -In that sense, GR's "curved space" is a reflection of a curvature mechanism all the way back to a yin-yang oscillational setting which immediately preceded the first elemental etheric energic units, with the primal units winding around due to their electro magnetic moments, which had a finite width, the result at larger and larger energic scales averaging out to a broader curvature pattern as we observe in the cosmos. -This attempt to clarify is not meant to get approval from my Forum critics, but to make the record clear as to the Aug. 9 Post.
    This nonsense about "ether", "instantaneous resonances between elemental etheric energic units", "yin-yang oscillational setting" and so on has no place in the main sections of a science forum. I suggest this be separated out and trashed.
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    Quote Originally Posted by AlexG View Post
    Quote Originally Posted by PetTastic View Post
    Quote Originally Posted by AlexG View Post
    If the lensing effect was due to gas refraction, wouldn't we see spectral lines due to the gas?
    I thought we did see abortion lines from galaxy halos and the inter cluster medium, that is how we know it is there.

    Am I wrong on this
    We don't see absorbtion lines in the lensed light, other than the standard lines we see in any intergalactic light. The fact that there are no additional lines is one way we know that the light is not interacting electromagnetically.
    NASA - The Milky Way's Hot Gas Halo

    From what I understand, it is now assumed that most galaxies have hot gas halo extending out to 6 times the radius of the galaxy or more.
    Also when talking a about galaxy clusters, the detectable (high metal content) intercluster medium extends well past the galaxies, and it is assumed the primordial gas halo is larger still.

    From this, I am assuming that the galaxies and clusters causing lensing effects are not special and have hot gas halos.

    other than the standard lines we see in any intergalactic light
    If we assume most galaxies do have halos with a visible cross section area 36 times bigger than the visible galaxy, then we are looking through many overlapping halos even at relatively short intergalactic distances.

    The Andromedia galaxy halo must cover a very large area of the night sky.
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