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B Are Black Holes just stars?

  1. Feb 9, 2017 #1
    Purely theoretical question and would like to know if it is impossible or viable.
    I was thinking that we see stars based on the light it emits and how there is a relationship between mass, density and the wavelength of the light. So what if a black hole is just a super dense star that emits solely UV wavelengths, which is why we can't see it. Think about it.
     
  2. jcsd
  3. Mar 19, 2017 #2
    Fairly certain no, blacks holes let no light out,the gravity is too strong, that's why it's black. Cameras pick up Uv, if your theory was true than black holes would be easily spotted.
     
  4. Mar 19, 2017 #3

    phyzguy

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    This is certainly not the case. We have telescopes that see all across the EM spectrum, from the radio up to very high energy gamma rays, so we would see objects like you posit. Also, even a very hot object whose spectrum is peaked in the X-ray region, emits plenty of visible light. A blue supergiant star like Rigel is hot enough that its spectrum peaks in the UV, yet it is easily visible. You should study more about the theory of black holes. There are sound theoretical reasons why they cannot be just very dense stars.
     
  5. Mar 19, 2017 #4

    mfb

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  6. Mar 19, 2017 #5

    Vanadium 50

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    Thing is, we have. We're not the ones who haven't thought about it. As pointed out, there are stars (like Alnitak) which peak way in the UV, but we can see them just fine.
     
  7. Mar 20, 2017 #6
    It turns out that in the nucleus something called electron degeneracy pressure, or neutron degeneracy pressure can hold it up as long as it's less than maybe one or two solar masses, but by the time the iron core is more than two solar masses there is no force humans know about that can stop it collapsing.

    It can't be a star. 70% sure.
     
  8. Mar 20, 2017 #7
    Just to be clear though, when held up by degeneracy pressure, they are not black holes, they are just normal exotic objects like neutron stars or quark stars.

    Black holes are mostly observed through x-ray, but you can't see the black hole itself. It's black, not light escapes it's gravity. But as particles get pulled down into it, they heat up and glow.
     
  9. Mar 20, 2017 #8

    phinds

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    As Vanadium pointed out, LOTS of people have thought about it. Trying to think outside the box is a good thing but it's a good idea to first study and learn what's IN the box and what thousands of physicists have already confirmed about what's in the box.
     
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