Blackhole Definition and 125 Threads

Hi all, The traditional image of a "feeding" black hole has jets spewing from either pole of the axis of rotation. I know that these jets are accellerated to almost the speed of c, but I have been unable to determine if these jets are of mater / particles or energy. Could you tell me which...

when massive stars run out of fuel for nuclear fusion it loses the electromagnetic outward force to negate the inward pull of gravity so gravity gets an upperhand over outward force and thus gravity jampack the rest of matter so tightly that one spoon of Blakhole matter (nuclear fusion residue)...

with the newest discovery of biggest black holes in the universe, i suddenly had this weird thought: what if they're a draining hole of the galaxy, the spiraled arms and the shape, all looks awfully similar to a whirlpool, with black holes at the center of nearly all galaxies

So I am just starting to understand QM and relating it to my own ideas... Within the event horizon of a black hole there can be no conscience observer, so all matter held within would be in superposition and in no way could we collapse the wave function of a particle. So doesn't that mean all...

than why center is the brightest part of galaxy? shouldn't black hole suck all the light in? and if so, the more close to center of galaxy, the more time flow slower right? ...... English is not my native language, forgive me If I'm wrong in spelling or gamma

Why dark matter can not collapse into a black hole under it's own weight?

According to Blackhole thermodynamics a black hole has an entropy that is proportional to its surface area and a temperature called the Hawking temperature. If one multiplies the Hawking temperature by the entropy one gets a thermal energy. Would this energy be equal to the mass/energy of...

There is a jetstream of particles (mostly electrons and photons) coming out of the black hole. But nothing escapes from a black hole because its gravity is so strong. So how do these particles come flying out of a black hole?

Blackholes suck everything inside them. I was wondering if there is anything opposite of a black hole. I've heard that there's a "white hole" theory which states white holes are the opposite of a black hole. Is it true that white holes are the opposite of black holes. And what are white holes?

I was wondering if we were to take two black holes, with their event horizons touching each others, what would happen? Both the black holes would be trying to suck the other one up. I'm sorry if this question sounds stupid but please share your ideas about this topic.

Greetings all, Is it possible that black holes are the result of collapsed dimension as opposed to huge mass/gravity events? Perhaps, the event horizon is shredding 3d objects and creating new space expanding the universe and forming the stuff of the galaxy around them. Could the curve of a...

From a far away observer, thing falling into a BH takes infinite time to cross the horizon. At the same time, the horizon radius is proportional to BH's mass. But if we never really see any energy fall into a BH, how did it acquire a horizon in the first place as seem from outside? i.e. What...

Saw somewhere that the force of gravity "cancels out" in that if in the approx. centre of the Earth you would feel no gravity (net zero). Does a black hole "start" forming from a particular point? (ie where gravity is strongest) Or "start" to form from the centre out? Or does it all just...

Homework Statement In the Schwarzschild Slalom, brave athletes dive from a platform orbiting at a distance of 1 AU from the singularity at the centre of a black hole with a mass of 10 MSun. The competitor who can get closest to the singularity, and survive, wins the event. (The rules state the...

Is there an exact relationship between the size of a galaxy and the density of its black hole?

If nothing can escape black hole(not even light), how can it radiate X-ray?

ok il say this now I am curious what would happen if you were able to bend the accretion disk and the ergosphere so that they bend passed the outer horizon and into the inner horizon were the singularity is located i know this is a 0.0000000000000000001 chance of happening but it would be a...

Homework Statement From our perspective a spaceship is traveling towards a black hole 9 light minutes away at 0.995C, another spaceship is traveling towards the black hole, traveling at a -0.03c from the point of view of the first spaceship. is it possible for the first spaceship to stop the...

Hi,all, the problem is: you and me observe a star, and the star moving with velocity V relative to me, and you are in the rest frame of the star. Then in my frame of reference, I saw the star length contraction in the direction of its motion relative to me, hence its volume is smaller than...

How does the gravity affect of a black hole pull in light? aren't photons massless?

Does the gravitational force of black holes pull matter in at speeds faster than the speed of light? (when the matter has passed the event horizon that is?) Or does the matter just stop moving out and in? and stop where it is? Or do we not know anything about this just yet... which I'm...

Shouldn't there be halo of EM waves around all the black holes? When a star falls into a black hole, there has to be some radiation perpendicular to the black hole, which is at some point at the right distance to form a halo. Is the amount of bending of light due to gravity same for all EM...

hey there, I'm interested in (eventually) simulating light ray paths near black holes, starting with schwarzschild black holes and working my way to kerr-newman black holes. I have a good understanding of the nature of black holes but have trouble when it comes to the equations. My background...

I'm sure most people here have heard about the microwave "invisibility cloak" that was made with metamaterials. For those that haven't heard, basically electrodynamics can be rewritten to handle changes in refractive index of materials with GR like tools where instead the background is...

Is everything "else" black hole? A black hole is something form which it is impossible to escape; even for light, and so no information can reach us form it Except for measuring its gravitational effects it produces, we can't tell that its out there or not. So it means that if form some...

i don't know much about the subject but since I've gotten interested in it there is something that has been on my my mind. if light would pass through the event horizon in a black hole the gravity would be to strong for it to escape. since it can't escape it would be pulled down to the point...

I've heard it said that any object that wants to escape another object's gravitational pull must travel at the object's escape velocity. I assume this is incorrect, and would only apply to something with an initial velocity at the escape velocity (like a bullet from a gun would need to travel at...

what is the difference between black hole and worm hole

http://www.cnn.com/2009/TECH/space/04/27/falling.into.black.hole/index.html In this article, in couple of places they mention about space moving faster than light. It's incorrect, right? (from the article) . . . . Hamilton also described them as places where space is falling faster...

If a stable BH exists?. By stable I mean not growing and not shrinking. How then does its radius depend on a homogenious (or inhomogenious?) density outside this BH? I suppose its radius is then anyhow larger than its Schwarzschild radius.

In thermodynamics we have a law that says that the entropy of the universe must always increase, though the entropy of sub-system can temporarily decrease. This increase of entropy generally happens through work -> heat processes (ie friction). We also think of the diffusion of atoms in a...

http://arxiv.org/abs/0901.0640 Horizons and the cosmological constant Krzysztof A. Meissner 6 pages (Submitted on 6 Jan 2009) "A new solution of the Einstein equations for the point mass immersed in the de Sitter Universe is presented. The properties of the metric are very different from both...

I am not very versed in physics but if it was possible to collide antimatter with antimatter would that create a black hole?

Does a Schwartzchild black hole have a singularity at its center?

If we can agree that a black hole can exist, and that its gravitational field is intensified with its mass, the we can also agree that its gravity can create one hell of a gravitational lens. If that is the case, and EM radiation, whatever the frequency, is directed towards the black hole...

Is it dumb of me to think that a black hole just becomes so massive at some point, it basically tears a hole thru the singularity and explodes outwardly like a big bang (through spacetime into another universe or something), or a pin finally pushed thru an extremely tight baloon? just curious...

What happens if two black holes of identical mass collide, but one is anti-matter and the other is regular matter? Would all of the matter anihilate in a gigantic explosion of photons which could be detected by a far away observer? Or, would all of the radiation energy, which would still have...

are all laws of physics break only at singularity Or laws of physics break even after event horizon?what is the difference

Classical black holes said to have zero temperature...but in BBT,it is same like a black hole where matter is compressed but it said to have high temeprature...both black hole and matter at bigbang is very compressed then why classical black holes have zero temeperature and big bang has high...

escape velocity v = (2gr)^1/2 for black hole, (2gr)^1/2 > c g > c^2/2r Now wat could be the minimum value of g for black hole

this may be very silly question but i want to confirm with you guys...Its been said when light goes into black hole it can't escape but do we have any proof or observation for light entering a black hole and disappearing..has anyone observed light entering black hole and disappearing?

I am currently reading A Brief History of Time and after reading chapter 7 there are still concepts which I do not understand. Hawking explains that particles go into black holes while antiparticles are thrown outwards into infinity. How and why does this happen? He also goes on to explain...

Can a black hole be accelerated to go faster than the speed of light? I've heard that when dealing with the moments of inflation and also with relation to warp engines, space itself can move faster than light. I've also heard that a black hole is a region of space that can move. So can it?

I know that we can only create small amounts of antimatter. But, suppose that we could create lots and lots of antimatter and we kept sending it into space to some empty place far away from our solar system. We keep sending antimatter to the same spot until the mass is enough for it to collapse...

Ok, I am no brilliant scientist like the rest of you folks but I have had a little theory rolling around in my head for some time and I would love to hear from you smart folks why this couldn't be the case. So here is a simple explanation of my theory. Basically the idea goes like this. Two...

high energy photons are emitted from accretion disc of black hole...are nuclear particles like electrons,protons also emitted in this process? are there any observation of particles emitted?

In the past two years work by Ashtekar and others in Loop cosmology has modified the LQG dynamics. Two postdocs at Portsmouth, one of whom is an Ashtekar PhD, have recently studied the Schwarzschild black hole using the improved dynamics. They got some new results which seem to point in the...

if i threw a string from a great distance into a black hole what would happen? if something was attached to the other end of the string would that thing eventually get realed in?

Does black hole have strong magnetic field?? As we all known: neutron-star has strong magnetic field! Does black hole have strong magnetic field too?? Thank you in advance!

Once enough mass in the form of hydrogen has been swallowed up by a black hole why can't a new nuclear reaction occur within a black hole creating enough of an outward pressure to uncollapsed it.