# Tag Info

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The light due to Hawking radiation will only ever be detected from very tiny black holes. The Hawking radiation scales as the inverse square of the black hole mass, but the radiation causes the black hole mass to decrease. This causes accelerated emission, such that all tiny black holes will go through a phase of emitting all their rest mass as $10^{22}$ J ...

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Hawking radiation is such a miniscule effect we can be sure we'll never detect it for a real astrophysical black hole. The Wikipedia article gives some numbers: For a black hole of the mass of the Sun, the power emitted in Hawking radiation amounts to $9\times10^{-29}\ \mathrm{W}$. Even if all this energy were converted to visible-light photons ...

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To expand a bit on the others' answers, a couple of ways to visualize/understand the difference between intrinsic and extrinsic curvature: Intrinsic curvature, as the name suggests, only deals with stuff that lies inside a surface/space/manifold etc. (I will use the term manifold) If your lines, triangles, etc. don't work the same way as they do in ...

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Is a black hole a 3D hole? I think so. Some people will say it isn't really a hole, but I think it is. That's because I think the "frozen star" interpretation is the one that's right. You can see a mention of that in Kevin Brown's article The Formation and Growth of Black Holes. He doesn't favour it, many people don't know about it, and others maybe hate ...

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A black hole is a 4D object, but that's because all objects are 4D as they live in a four dimensional spacetime - three spatial dimensions and one time dimension. However what I suspect you're asking is whether there has to be an extra spatial dimension for space to bend in, making five dimensions in all. If so, then the answer is that no there is no extra ...

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In general relativity it is believed that the Schwartz Child radius is approximately Ricci-flat spacetime, meaning that there is little tidal force or at least no amount that should be surprising. A smaller black holes have a greater tidal force because the Schwartz Child radius is closer to the singularity than in a bigger one. In this theory falling in ...

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We don't have any adequate theory to describe what happens to matter inside the event horizon (and some theories even say that matter never actually crosses the event horizon). But let me address you specific questions: 1) It's possible that matter entering a black hole is converted into a new form of matter. 2) I have no idea what negative matter would ...

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According the old classical general relativity, The event horizon can be approximated by flat spacetime so nothing happens when it crosses. But space and time coordinate interchanged for an outside observer, so its energy and momentum are interchanged for an outside observer. However, firewall is a new phenomena considering quantum effects, it says the event ...

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In very simple terms, everything that enters a BH will become part of it. So, there is no question of A ever being able to catch the ball. You could say that there is a Fundamental Law of Nature- " Thou shalt not travel faster than light"(sentence taken from a TV show, initial speaker unknown to me) Which means that no form of matter that belongs to this ...

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No observer will ever observe a true horizon because it takes an infinite time to form. All we real observers will ever see is an apparent horizon, though for typical black holes the difference between the real and apparent horizons is extremely small. The Hawking radiation does depend on the motion of the observer. For example a freely falling observer ...

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A stellar mass black hole usually forms during a core collapse supernova of a very massive star. Our understanding of star formation is that most stars will have some angular momentum, and some of this angular momentum will be passed on to the black hole which is produced when the core collapses. This means that, as you mention, most black holes will be ...

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