**General relativity**. In a “hypernova”, the very energetic supernova creates a: black hole with focused bipolar jets from its poles.

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What is the event horizon of black holes?

This singularity has a region within which the escape velocity exceeds the speed of light, defined by the Schwarzschild radius. The boundary beyond which not even light can escape the black hole is called the event horizon, which is a boundary in spacetime. Image: Copyright © 2017 Martin Silvertant. All Rights Reserved.

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What is a a black hole?

A black hole is a location in space with such a strong gravitational field that the escape velocity exceeds the speed of light. What this means is that you require a velocity greater than the speed of light (a physical impossibility) to escape the black hole, as can be seen in the image below. Image credit: Frigg MnSU Astronomy Group

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What happens to spacetime when a black hole rotates?

As a black hole rotates, it twists spacetime in the direction of rotation at a speed that decreases with distance from the event horizon, meaning that spacetime closer to the event horizon will be twisted to a greater degree than the space further out from the event horizon. This process is known as the frame-dragging.

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What causes the Schwarzschild radius of a black hole to become oblate?

The rotation of the black hole causes the Schwarzschild radius to become oblate due to the centrifugal force. Also, the gravitational singularity is no longer a point source, but a two dimensional ring singularity.

What would a clock on a spaceship nearing an event horizon be observed as?

As a spaceship nears an event horizon, a clock on the spaceship will be observed: to run slowly.

When observing an object such as a space ship that is moving very quickly relative to you the length of objects on that object will appear to be quizlet?

When observing an object, such as a space ship that is moving very quickly relative to you, the length of objects on that object will appear to be: shorter than when they are at rest. The orbit of a close binary system involving two neutron stars gradually shrinks in radius.

What can we detect from matter that has crossed the event horizon of a black hole?

bend towards the star due to gravity. What can we detect from matter that has crossed an event horizon? rapid gas motion and intense energy emission.

Why is light increasingly redshifted near a black hole?

Why is light increasingly redshifted near a black hole? It must expend energy to escape the gravitational pull of the black hole. This is correct! As light loses energy, its wavelength increases (since wavelength is inversely proportional to energy), causing the redshift.

What happens when we go into black hole?

If you leapt heroically into a stellar-mass black hole, your body would be subjected to a process called ‘spaghettification’ (no, really, it is). The black hole’s gravity force would compress you from top to toe, while stretching you at the same time… thus, spaghetti.

Which of the following accurately describes changes to a star when it first moves off the main sequence of the HR diagram?

Which of the following accurately describes changes to a star when it first moves off the main sequence of the HR diagram? Explanation: When a star moves off the main sequence, radiation from the hot core causes the outer layers to expand and cool. The star becomes a red giant.

What happens to time near a black hole?

As you get closer to a black hole, the flow of time slows down, compared to flow of time far from the hole. (According to Einstein’s theory, any massive body, including the Earth, produces this effect.

What happens to the passage of time near the event horizon of a black hole?

Time slows down near a black hole due to the extremely strong gravitational field of the black hole. According to the theory of general relativity, this phenomenon is due to the gravity of the black hole curving spacetime in a way that affects all measurements of time and space near the black hole.

What happens to time at the event horizon of a black hole?

An object approaching the event horizon would appear to be slowing down as it approaches the black hole instead of speeding up as we would expect. This is because of time dilation, which slows the passing of time for an object moving close to the speed of light with respect to an outside observer.

What causes gravitational redshift?

The gravitational redshift happens when light tries to escape from a gravitational field. This is actually a phenomenon that you can explain using ordinary newtonian physics.

Do black holes emit radio waves?

Although light can’t escape a black hole’s event horizon, the enormous tidal forces in its vicinity cause nearby matter to heat up to millions of degrees and emit radio waves and X-rays.

How does the radius of event horizon changes when you added mass to a black hole?

Feed the black hole some mass, and the horizon will grow—but not very much. Doubling the mass will make the black hole 6 kilometers in radius, still very tiny on the cosmic scale. The event horizons of more massive black holes have larger radii.

How does a black hole rotate?

As a black hole rotates,** it twists spacetime in the direction of rotation at a speed that decreases with distance from the event horizon, meaning that spacetime closer to the event horizon will be twisted to a greater degree than the space further out from the event horizon. ** This process is known as the frame-dragging.

Why is the gravitational field of a black hole so extreme?

**A black hole has more mass and a far smaller radius (presumed to be a point source), ** so its gravitational field when you get close to it is really extreme. Extreme enough so that not even light—which has the greatest speed possible in the universe—can escape, as we saw at the beginning.

Why is the Schwarzschild radius oblate?

Image credit: Boundless. The rotation of the black hole causes the Schwarzschild radius to become oblate due to** the centrifugal force. ** Also, the gravitational singularity is no longer a point source, but a two dimensional ring singularity.

What does it mean when a black hole is black?

A black hole is** a location in space with such a strong gravitational field that the escape velocity exceeds the speed of light. ** What this means is that you require a velocity greater than the speed of light (a physical impossibility) to escape the black hole, as can be seen in the image below. As no light can escape a black hole, it’s black.

Why can’t objects in the ergosphere be stationary?

Because of this** dragging effect **, objects within the ergosphere cannot appear stationary with respect to an outside observer at a great distance unless the object was to move at faster than the speed of light with respect to the local spacetime, which is not possible.

What is the shortest path between two points in a curved space?

A** geodesic ** is the shortest path between two points in a curved space. As matter falls into the black hole, it takes the shortest possible path, and beyond the Cauchy horizon space – and time** geodesics ** become reversed. So beyond the inner event horizon, you are no longer traveling through space, but through time.

What are the two main components of a black hole?

As you can see, there are two to three additional components compared to the basic black hole anatomy. A black hole has an** outer event horizon, ** and an** inner event horizon, ** or** Cauchy horizon **. One side of the Cauchy horizon contains closed space-like geodesics, and the other side contains closed time-like geodesics.