Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: jamie tombs on 30/09/2011 19:01:04
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jamie tombs asked the Naked Scientists:
Hi guys and gals,
I am a big fan of the show (http://www.thenakedscientists.com/HTML/podcasts/). I have been wondering about things travelling faster than light. I understand that this would break the laws of physics which we must all live by , but seeing that our laws of physics break down when it comes to black holes, so my question is this. Would matter travel faster than light when it is 'consumed' by a black hole ? Would this even be possible ? or do we just not have enough information on the physics of black holes to have an informed guess ?
Once again i would like to thank all involved with the show (http://www.thenakedscientists.com/HTML/podcasts/). Keep up the good work!
Yours kindly,
Jamie
What do you think?
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No, not as I think of it anyway. As long as we expect a Black Hole to have a gravity inside the Event Horizon it should obey the laws we see outside it. And outside gravity 'propagates' at 'c', never surpassing it. What happens at that center though? That I don't know, but I sure would like too :)
The other answer is that we stop at the event horizon, because that will be the last point of measuring for us. And without measurements it will be very hard to prove any theory.
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I agree with yor-on. I would just add, I imagine all black holes to be rotating and quite possibly at relativistic speed. This coupled with the intense gravity would make 'frame'dragging' a very real effect. If that's the case then everything would probably become very 'blurred' before even reaching the event horizon.
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Do black holes accelerate things to faster-than-light speeds?
As mentioned in another thread could a matter black hole convert matter into antimatter?
If the answer is yes then antimatter particles would probably be expelled along the lines of the axis and at relativistic speed.
It has been proposed that anything travelling faster than the speed of light is actually going backwards in time.
Antimatter particles expelled from a black hole would be going backwards in time.
So the question is can or do antimatter particles travel faster than the speed of light in a matter universe?
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Depends on what you mean by 'anti matter' Mike?
No, we already have anti matter, if you by that mean being the 'opposites' of a known particle. The - electrons anti particle is called the + positron, and was found to exist naturally in cosmic radiation. And in 1995 CERN created the first 'artificial' anti particles, but those particles obey the same laws ('c' etc) as all other particles, as far as I know. Anti particles as I understands it are the direct opposite of the particle they depict, and when colliding both should annihilate, into 'energy'.
Then you have 'mirror particles' (http://en.wikipedia.org/wiki/Mirror_matter) too, you might expect them to exist through 'symmetry' and maybe, they do?
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What is slightly 'weird' is that they will create a radiation. One might assume, with their description being 'anti' that they just would take each other out, and cease to exist, but in the case of them meeting each other...
"When matter comes in contact with antimatter, an enormous amount of energy is given off in the form of electromagnetic radiation. The total of the mass of the two particles is converted into electromagnetic energy through Einstein's famous
E = mc² equation.
That means that if a gram of matter (0.001 kg) would come into contact with a gram of antimatter (0.001 kg), the amount of energy that could be released would be E = (0.002)*(9*1016) = 1.8*1014 joules or newton-meters. This is about 40 times greater than the energy of the first atomic bomb."
And as gamma rays as I understands it.
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The thing is, when I read 'anti matter' I don't really see 'annihilations' ending in a 'energy cloud' of radiation. And maybe you don't either? When I read that word I intuitively envision 'something' taking out 'something else', leaving no trace of their existence.
And if that is what you are thinking, then physics don't have a answer. Energy seems to be what it all comes down too inside SpaceTime. That and conservation laws, and symmetries of course. That is what we see here so far. So from that point of view it stands to reason that all annihilations will bring with it some sort of 'radiation'.
One could ask if 'energy' 'propagates'? At the speed of 'c' then? But as there is no way to touch 'energy' except as a result of transformations, as I know that is, it then becomes a very tricky question.
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And 'energy' is not only radiation, it's also what we expect to create the room we live in, and so all space, and as space is time, mass, and so possibly 'gravity'. But I don't know about that last one, maybe gravity is a way of transforming/increasing/decreasing 'energy' but? Gives me a headache that one.
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yor_on
I was using the word antimatter in the sense that a positron is the equivalent antimatter particle of the electron. A positron can be thought of as an electron going backwards in time.
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The thing is, when I read 'anti matter' I don't really see 'annihilations' ending in a 'energy cloud' of radiation. And maybe you don't either? When I read that word I intuitively envision 'something' taking out 'something else', leaving no trace of their existence.
And if that is what you are thinking, then physics don't have a answer. Energy seems to be what it all comes down too inside SpaceTime. That and conservation laws, and symmetries of course. That is what we see here so far. So from that point of view it stands to reason that all annihilations will bring with it some sort of 'radiation'.
One could ask if 'energy' 'propagates'? At the speed of 'c' then? But as there is no way to touch 'energy' except as a result of transformations, as I know that is, it then becomes a very tricky question.
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And 'energy' is not only radiation, it's also what we expect to create the room we live in, and so all space, and as space is time, mass, and so possibly 'gravity'. But I don't know about that last one, maybe gravity is a way of transforming/increasing/decreasing 'energy' but? Gives me a headache that one.
Surely 'energy', used in that sense, is actually referring to photons which are pure energy and only propagate at the speed of light?
Perhaps the only thing in the universe that has not been made (directly) from energy is gravity (which is an affect of mass). I think energy in a sense is the opposite of gravity but is a component of time, the other being gravity.
Gravity decreases energy or decreases useful energy and is probably the universes main source of entropy.
Why, because it takes more energy to do anything in a high gravitational field than in a low one.
When two objects gravitationally combine, time passes slower for them as a pair than it did for them singly. This is equivalent to a reduction in (useful) energy.
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You hit a sensitive spot there Mike. 'Energy' is not only radiation, although I agree on a 'photon' being the best description of 'visible energy' I know of. But 'empty space', macroscopically as well as Quantum mechanically, must 'contain 'energy'' too. We like to think of it as radiation, and from a QM plane, discussing 'zero point energy' we treat is a radiation although 'virtual', unmeasurable for us.
But as far as I can see everything that exist, except possibly (?) gravitation is energy. The difference becomes from what scale we measure it, and also what properties we observe/define something to have macroscopically versus quantum mechanically.
If you take space it is macroscopically resistance less, no 'friction', it contains only two things as I see it. 'Distance' and 'Gravity'. The three-Dimensional aspect of it we see, I see as a result of gravity, and maybe all measurable 'distance'. Without 'gravity' I wonder if it still would be measurable for the observer. But from a QM perspective it's filled with 'virtual radiation/energy'. From a more main stream perspective it is defined through 'dimensions', three of them creating a 3-D environment with time making it possible to measure them. Then 'gravity' comes laid upon this.
I'm not sure I agree on that.