Holes Definition and 1000 Threads

Whenever I see any image of a black hole or in television or anywhere, I found there is a ring of light around the black hole. In discovery channel, I heard them saying that scientist found rings of light in space which had black region inside it. It was also one of the evidence with the help of...

what is the mechanism of small holes in auditorioms used as sound absorbers

Where can i read about the solution of Einstein equations with spherical symmetry in tetrad formalism?

It seems like black holes could just as easily be expelling the matter they rip up. Couldn't a black hole just be something that rips matter apart atom by atom and then blasts it back into space? In this case there wouldn't be a need for a singularity. Quasars are one example of how they...

Have we ever observed microscopic black holes in the LHC?

I was playing around with some equations and I found a reason why I think micro black holes cannot exist. This proof requires a few assumptions which I have tended to find to be a scientific consensus. They are the following. 1) The smallest mass a black hole can have is the Planck mass which...

When it comes to dark matter; Has the mass of the super-massive black holes residing at the core of every galaxy been taken into consideration? Could the total mass of all black holes account for the missing mass in the universe?

A description of problems with the common understanding of black holes by this layperson: I have been contemplating black holes since I first heard about them at a lecture series by the then director of the Griffith Observatory in Los Angeles, by Dr. William J. Kaufman circa 1964. It seems...

According to a recent published article, Physicist Leonard Susskind feels, along with Niels Bohr, that rather than try to come up with a mental picture of what objective reality is, scientists should limit themselves to creating hypotheses and testing them empirically. Susskind contends that a...

Is Schwarzschild radius trying to state the gravitational field on the event horizon of a black hole? If not, what is it trying to state? Can you give me a example using his formula to figure out the gravitational force of a black hole in the event horizon? Do you have any links I can...

I didn’t believe it when I first heard it. I don't know how to reconcile this fact with what I understand about the known laws of physics. It appears to be one of the grandest mysteries I can think of. I understand that most of the universe is empty space but zero volume is different. Anyways...

"Black Hole Masses are Quantized," Gia Dvali, Cesar Gomez, Slava Mukhanov, http://arxiv.org/abs/1106.5894 There is a nontechnical summary on the arxiv blog: http://www.technologyreview.com/blog/arxiv/ , along with some inflammatory and uninformed speculation about safety at the LHC, including...

Hello to all physics community! I have a question concerning black holes. Are black holes, real holes? And which is the difference between black holes and wormholes?

I have read that it is possible that primordial black holes could have formed in many different sizes, from micro black holes to hundreds of solar masses, my question is this. What is the smallest black hole that could survive from this time until now, without being destroyed by hawking...

In an earlier post I make the controversial suggestion that the universe was very heterogeneous in the early stages. I have another conjecture that goes along with that one. Please try to read this with a bit of an open mind. Imagine that there is an upper limit to the size of a black...

Could the primordial black holes that seeded the first galaxies have been formed from spacetime that never expanded below the critical threshold for black hole formation? If quantum jitters caused the variation in densities seen in the cosmic background radiation, could islands of higher density...

The news always depicts them as real http://www.bbc.co.uk/news/science-environment-13964767 But as far as I gather from reading this forum and wikipedia, black holes are always said to be "candidates" Has it been proven "beyond a reasonable doubt" that they exist?

From another post on this forum, we have an excerpt of Susskind's "The Black Whole War": To figure the increase in mass, let's figure the energy of the photon and then convert that to an equivalent mass. Photon energy is E = hf and if wavelength is R[sub]s/SUB], from v = f x...

Hi every1 My question is: we know nothing travel faster than light. Gravity travel at the speed of light, right? Now: light cannot escape from a black hole. So: gravity cannot escape from a Black Hole. Then... why can we feel the gravitational field of a black hole if gravity cannot be...

Locally, photons "blue-shift" when falling down a gravitational field. What happens when they arrive at the Planck frequency? Do they turn back into matter?

I know we haven't yet discovered that a technicolour force actually exists, but it seems to be worked out to some extent mathematically? (Not to say there hasn't been a false alarm, or two) I'm just curious that if it did end up existing, has the math been worked out far enough to see if it...

I'm pretty ignorant about astrophysics, but this made it into the newspaper today, and it seemed interesting. http://arxiv.org/abs/1106.3079 "Black hole growth in the early Universe is self-regulated and largely hidden from view," Treister et al. "The formation of the first massive...

I was wondering if black holes are insanely hot, my guess is they are because so much matter has been crushed together causing friction and energy. Is this right? Thanks. PS: if it's something a 14 year old wouldn't understand, please give me a url link to wikipedia where I can study it...

Hello! I'm redesigning my never-to-be-finish sci-fi novel, yet another futile to come up with scientifically based interstellar travel propulsion. My latest consideration is based on article[1] and possible extensions of those ideas. Anyway, I'm looking for an independent opinions on the...

Here's an idea I came up with recently, that I wanted to share: Physics is unitary and CPT symmetric, and therefore no true black holes exist, since they imply information loss and non-reversibility. Every "apparent" event horizon is really a separation of two mostly causally disconnected...

Here's an idea I came up with recently, that I wanted to share: Physics is unitary and CPT symmetric, and therefore no true black holes exist, since they imply information loss and non-reversibility. Every "apparent" event horizon is really a separation of two mostly causally disconnected...

Black holes suck in everything around them. My 5 year old knows that one. It's all over TV, etc. But what about the original star? Wouldn't that have just as much gravity? Wouldn't it do the same thing with the strength? Is it just that black holes are more exciting to talk about?

Jet propelled Black Holes by ion engine? Might asymmetry of jets for BH, together with Newton’s Third Law, result in high velocity over time, from an ion engine? Perhaps even several 100 km/s? Might Large Synoptic Telescope detect motion of associated binary massive star?

From reading various articles my understanding is that BH are gravitationally extreme - although from a distance they are gravitationally the same as any other object it is inside the Schwarzschild Radius EH where BH's differ from other large masses. The "singularity" is the point at which...

Hello, I have been designing a pressure vessel for the last week. I have based all my maximum allowable stresses on ASME code but can't figure out how to include drilled holes. I plan to be using a pipe welded to a cap at one end and attached to a blind flange with holes drilled in it at the...

Hi all. I understand that a hole is the absence of an electron. I have come across textbooks with instances where they talk about movement of minority carriers, and movement of majority carriers. Since the hole has to be one of them, they are referring to moving holes. But, how can a hole...

if black holes are 2 dimensional representations of our 3 dimensional universe, does that make our universe a 3 dimensional representation existing on the edge of (or entirely inside) a 4 dimensional universe? or to a 4th dimensional being would our 3 dimensional universe be considered a "black...

I look at time and space as a fabric, just as Einstein stated. However I look at time and space as a fabric moving through us. Moving through all organic matter like a river. So time is merely flowing past us just as space is. Is this the case? If we are moving around the sun in a trench of...

Homework Statement This problem is awesome! I like this chapter; Its really interesting. I think I just get a little impatient when I can't figure out the answer right away... I appreciate any help. Miniature black holes: Left over from the big-bang beginning of the universe, tiny black...

Is mass, angular momentum, and charge sufficient for black hole characterization? Or is also entropy, and hence surface area, also required? Thus is the shape for a given mass black hole also a required consideration?

How a quasar beam can get out of a black hole if no light is suppose to be able to get out of the event horizon of a black hole. ? Is it because the beam is created outside of the event horizon ? From what I understand quasar is created because of excess of matter on the black hole correct me if...

If you were to greatly increase the elctrical charge of an extremal Black Hole, (ie, drop a lot of electron in) what exactly would happen to it? I know the electrical repulsion would become more powerful than the gravity, so would it tear itself apart?

Hi, Lay questions again. What's the real story - is a black hole potentially a worm hole? If someone theoretically entered a black hole, the common portrayal is experiencing tremendous acceleration. But with time compression, how different would that acceleration feel to the traveler...

In trying to compute deflection angles for photons given their impact parameter (closest distance of trajectory to centre of black hole if unaffected) I am trying to numerically integrate the following equation (d^2/d(phi)^2)(u)+u=3Mu^2. However I am stuck as to how to work out the initial...

Hello everyone if black holes have a gravitational pull so strong that nothing can escape, then why is it that they do not continuously consume dark matter? Yes i know its called dark matter because it doesn't not interact with other matter but it does have an effect on the rotational curves...

I understand why you would be ripped apart if you enter a black hole, but I don't understand the fact that if the black hole is large enough, You would not be ripped apart if you passed the event horizon. And, some black holes you would be ripped apart outside of the event horizon? Can...

Hey all, I may be way out of the ballpark here, but its something I thought about today at one of my Astronomy lectures. How come Physicists view a black hole as "Something" rather than "Nothingness" ? The Physics about Black holes is still some what uncertain, and we try out best to...

Dokuchaev, "Is there life inside black holes?" I thought this was pretty cool. "Is there life inside black holes?" Vyacheslav I. Dokuchaev http://arxiv.org/abs/1103.6140 Abstract: Inside a rotating or charged black holes there are bound periodic planetary orbits, which not coming out...

Suppose you take a quantity of matter and separate the protons from the electrons, Now drop the electrons into a black hole. My understanding is that photons are the force carriers for the electromagnetic field. Since no photons can escape the black hole there should be no electrostatic...

I stumbled upon an article while doing some research that had a statement saying that Hawking radiation can be found in places beyond black hole horizons. This lead me to this paper (which I'm not actually interested in beyond it's reference to the existence of hawking radiation outside of...

I think this subject may have been discussed here already; please point to the thread if so. I am unable to understand how Black Holes can form within the lifetime of the universe. If nothing can cross an event horizon in finite time, then it seems clear that the horizon can't form (at...

Several questions about escaping the event horizon of a black hole typical disclaimer: I am not a scientist so please don't scold me too much for curiosity. I imagine a large black hole with a less massive black hole in orbit around it. Light enters the event horizon of the more massive...

"It is theoretically possible for a traveler to enter a rotating black hole, avoid the singularity, and travel into a rotating white hole which allows the traveler to escape into another universe." Can anyone please expand on white holes?

Build a Dyson sphere around a black hole (this is a thought experiment), so no more mass "falls in". Line the sphere with insanely bright lights. What happens to the black hole? I ask this because Prof. Sean Carroll in "From Eternity To Here" discusses whether there is a limit to the...

a) If the sun were compressed sufficiently enough so that it would turn into a black hole, what would be the event horizon of such an object expressed in km? b) What is the event horizon for a black hole with a mass of 10 9 Msol? c) What is the event horizon for the black hole with a mass...