Physics Question
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Not all supernova become black holes though sooey. Some become neutron stars.
I did say Supernova, not Black Hole.
Not all supernova become black holes though sooey. Some become neutron stars.
I did say Supernova, not Black Hole.
You said our sun would finally become a supernova, which it won't.
The Chandrasakar limit also applies to Neutron stars i think.
There are two types of supernova as far as I know. One where a massive star reaches the end of it's fuel after converting through the elements up to iron, then it blows off its outer layers in a massive explosion while its core collapses to either a neutron star or a black hole, depending on its mass.
The other one is a type 1a supernova where a pair of stars are in close orbit and one is cannabilising the other. I don't know how they work exactly but when a critical mass is reached the feeding star blows off a lot of stuff in a supernova. Then the cycle repeats.
The 1a supernovas are always the same brightness, so astronomers have used them to work out the distances of galaxies by searching for them and looking at what there apparent brightness is.
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Type 1a supernovae aren't cyclic. They are a one time cataclysmic event. Novae are cyclic -but thats a different thing entirely
A type 1a supernova is typically caused by a white dwarf accreting matter from a larger star in a binary system. Once the accreted matter causes the white dwarf's mass to exceed approximately 1.44 solar masses (Chandrasekhar limit), it collapses and explodes as a supernova. Because the Chandrasekhar limit applies, the mass and therefore the luminosity of the supernova tends to be fairly constant which is why they're used as standard candles.
Type 1a supernovae may also be caused by 2 white dwarf stars merging.
The other type of supernova involves a giant star of at least 9 solar masses (anything less than this stays on the main sequence and becomes a red giant then a white dwarf which is the eventual fate of our own Sun) and there are several potential mechanisms involved in the collapse and final explosion. For stars less than around 150 solar masses, the fusion cycle runs from hydrogen through heavier elements until iron is involved. At that point, the fusion reaction required more energy than it produces (i.e. it becomes endothermic rather than exothermic) and the core rapidly collapses producing a powerful shockwave that blows off the stars outer layers in a cataclysmic supernova explosion. About 150 solar masses, a phenomenon called pair instability causes the hydrostatic equilibrium of the star to be lost and it collapses causing a supernova explosion - pair instability supernovae don't run out of fuel. If the progenitor star of a type 2 supernova is less than around 20 solar masses, the remnant will usually be a rapidly spinning neutron star (conservation of angular momentum) - these are responsible for the phenomenon known as pulsars. If the progenitor is greater than 20 solar masses then the remnant is likely to be a black hole although there is a very strange alternative for some intermediate mass stars where the collapse stops before a singularity occurs and a quark star is formed instead.
A type 1a supernova is typically caused by a white dwarf accreting matter from a larger star in a binary system. Once the accreted matter causes the white dwarf's mass to exceed approximately 1.44 solar masses (Chandrasekhar limit), it collapses and explodes as a supernova. Because the Chandrasekhar limit applies, the mass and therefore the luminosity of the supernova tends to be fairly constant which is why they're used as standard candles.
Type 1a supernovae may also be caused by 2 white dwarf stars merging.
The other type of supernova involves a giant star of at least 9 solar masses (anything less than this stays on the main sequence and becomes a red giant then a white dwarf which is the eventual fate of our own Sun) and there are several potential mechanisms involved in the collapse and final explosion. For stars less than around 150 solar masses, the fusion cycle runs from hydrogen through heavier elements until iron is involved. At that point, the fusion reaction required more energy than it produces (i.e. it becomes endothermic rather than exothermic) and the core rapidly collapses producing a powerful shockwave that blows off the stars outer layers in a cataclysmic supernova explosion. About 150 solar masses, a phenomenon called pair instability causes the hydrostatic equilibrium of the star to be lost and it collapses causing a supernova explosion - pair instability supernovae don't run out of fuel. If the progenitor star of a type 2 supernova is less than around 20 solar masses, the remnant will usually be a rapidly spinning neutron star (conservation of angular momentum) - these are responsible for the phenomenon known as pulsars. If the progenitor is greater than 20 solar masses then the remnant is likely to be a black hole although there is a very strange alternative for some intermediate mass stars where the collapse stops before a singularity occurs and a quark star is formed instead.
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Like I say Joe, the scientific community thinks that gravity travels at the speed, provided a link earlier and a reference to a science book, there may well be scientists who think otherwise though. But for now I am going with the scientific consensus that I can find at least.
Unless your name is Hawking and you are typing your messages with your cheek I will say you are wrong.
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Use your intellect. I am right. It could never happen in the real universe because matter/mass cannot just disappear. Therefore there is no 'real' answer to the question. Gravity may travel at the speed of light in the normal universe, but according to the question (which isn't possible) it doesn't apply. Find me a link that answers your question - not talking about gravity generally.
I maintain that:
The mass of the sun distorts space and gravity is the by-product.
Remove that mass instantly and you will remove gravity associated with that mass instantly.
Now use your noodle - not google.
I maintain that:
The mass of the sun distorts space and gravity is the by-product.
Remove that mass instantly and you will remove gravity associated with that mass instantly.
Now use your noodle - not google.
You're still thinking Euclidean space joe, you need to start thinking Riemannian mate.
In that case , Brighton would be go before us , on the Forest . Well it`s always had a floating population anyway
Wasn`t he a slum landlord, start thinking Riemannian mate.
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That statement asserts that we know what gravity is. We don't. All we know is that it's the weakest of the four fundamental forces and seems to be associated with mass. Current theories posit that gravity may not even be a part of our own universe but rather a force interfering from an external universe. We've not seen any evidence of gravity waves yet which, under Einstein's theories, should exist. Until some real proof is discovered (i.e. a gauge boson for the force or similar) then it's all just ideas.
However, there's sufficient evidence to support the idea that like other forces, it's limited by the physical rules governing other forces and matter which means that its effects are limited to the velocity of light in a vacuum (c). It's a force so if it's a part of our universe then there will be a particle that mediates it (a gauge boson) - same as the gluon for the strong force, w and z bosons for the weak force and photons for the electromagnetic force. The gauge boson for gravity even has a name (the graviton) we haven't discovered it yet though.
So, to answer the original question, if the Sun were to disappear instantaneously (violating several laws of physics in the process), the gravitational effects would take just over 8 minutes to manifest in the Earth's orbital path.
The question is about the speed of gravity, it was framed as the Sun and Earth so people could imagine the situation. As stated previously scientists have had the opportuniy to look at changes in mass of objects in space and its effects and have come to the conclusion that gravities effects "travel" at the speed of light.
In my question there is nothing to suggest gravity works any differently in this hypothetical situation than it does in the Universe at large.
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It's got nothing to do with the speed of gravity. That was never the question. And no, I don't google stuff like you do - I use my own brain power. I suggest that you try it sometime soon.
Take away the mass - and you take away the gravity. That's it. It's obvious to a genuine thinker other than a Googler.
Take away the mass - and you take away the gravity. That's it. It's obvious to a genuine thinker other than a Googler.
Clearly
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