Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: jeffreyH on 13/11/2016 21:20:00
-
Under some conditions it can appear that the jets from the poles of black holes are traveling faster than light. Could this be explained by the matter in the jets traveling into the future?
-
It reminds me of something similar to the speed expansion of the universe where objects seem to separate faster than the speed of light, that would mean rapid space expansion at poles, which is equivalent to antigravity. Probably because I'm tottaly against true time travel, but at least, this doesn't violate GR.
-
Under some conditions it can appear that the jets from the poles of black holes are traveling faster than light. Could this be explained by the matter in the jets traveling into the future?
Nothing is actually traveling faster than light. The jets have an apparent superluminal velocity due to their small angle to our line of sight. It is akin to the fact that if a object 1 light hr away and traveling towards me at 0.75 c will take 1.33 hrs to reach me, while the light leaving at the same time takes an hour. So to my eye, I see an image of the object 1 light hr away and twenty min later, it arrives. Its image will appear to travel at 3c, even though the object itself only is moving at 0.75c
-
Under some conditions it can appear that the jets from the poles of black holes are traveling faster than light. Could this be explained by the matter in the jets traveling into the future?
Nothing is actually traveling faster than light. The jets have an apparent superluminal velocity due to their small angle to our line of sight. It is akin to the fact that if a object 1 light hr away and traveling towards me at 0.75 c will take 1.33 hrs to reach me, while the light leaving at the same time takes an hour. So to my eye, I see an image of the object 1 light hr away and twenty min later, it arrives. Its image will appear to travel at 3c, even though the object itself only is moving at 0.75c
That is the way it is explained but I have some doubts. I am likely wrong but thought I would post the question to see what others think.
-
I never trust anything from the Daily Mail; but this is worth a look.
http://www.dailymail.co.uk/sciencetech/article-2853083/Scientists-lightning-sparking-supermassive-black-hole-appears-travel-faster-speed-light.html
“The flashes of radiation seemed to move 279 million miles across the event horizon in just 4.8 minutes.”
I am not sure I am interpreting this correctly. Is this saying that the “depth” of the event horizon; i.e. on a radial line from the centre; is 279 million miles?
-
To fill content the daily snail also appears to duplicate paragraphs. Suggesting their reporters may not be intelligent enough to understand their own story. Apart from that the lighthouse analogy was fun to read. Thanks for the info Bill. I hadn't seen you around for a while. Welcome back.
-
The main theory of jet formation is that it is produced in the accretion disc outside the event horizon. In this case, only the entire disc generates the beam in a joint oscillation that cannot exceed the speed of light. Thus in principle, the variation in the direction of the jet should be limited by the size of the event horizon and the speed of light.
The fact is, there are no really working model, contrary to what you may read in popular science news.
In my theory, the black hole is a real macroscopic ring at the event horizon with nothing but space in the middle plane. The jets are ejected in opposite directions in the middle plane. This would solve this riddle.
-
There is a way to explain this using nothing but GR.
Black holes suck space at a rate ai high that takes light an extremely long amount of time to cross the horizon. The jets though managed to do that extremely fast in comparison to that, but considerably less than the apparent speed of light under no gravity ( just not to be confused light travels the same speed everywhere but if space shrinks light can apear to slow down when viewed from outside the region that shrinks ).
At poles energy gets inside the hole the easiest but can also get out easier because of no spin.
At poles there is the possibility of no horizon but light would still slowly travel trough. The horizon may be harder to get through because it is spinning.
One scenario I can think of is that due to positive energy building up, the balck hole reduces the rate of space absorbtion just a little above zero (equivalent gravity effect can be calculated from the speed difference), only for short periods of time and only at poles.
If you know the mechanics of Black holes you can simply apply GR and find more possible explanations.
These black holes suck our space the universe is made of. The good news is, from time to time they expels it out.
The difference between the universe and a black hole is that outside a black hole there is space. Outside the universe there is nothing. Hence different dynamics.
-
GR alone dictates an event horizon, even for a Kerr black hole. Not even light can escape the event horizon. Spacetime is flowing inward at the event horizon, not outward. Thus, GR can't explain this. It doesn't mean there is no other possible common explanation, just that if there is, it will be explained outside the event horizon. Einstein did not think that such black holes would exist in the universe. He stipulated that his theory needs a description of the fields at the particles scale.
-
GR alone dictates an event horizon, even for a Kerr black hole. Not even light can escape the event horizon. Spacetime is flowing inward at the event horizon, not outward. Thus, GR can't explain this. It doesn't mean there is no other possible common explanation, just that if there is, it will be explained outside the event horizon. Einstein did not think that such black holes would exist in the universe. He stipulated that his theory needs a description of the fields at the particles scale.
First of all spacetime doesn't flow because time is already included, thus you have a single block. Shrinking space creates the flow.
Secondly I didn't say space flowing outwards in this post. Only in the previous one.
I see it, impossible to traverse the horison so fast unless the inward flow is reduced considerably.
It is not a question of an optical illusion. If the flow is not reduced at those moments, light would take bilions of years to cross the horison.
Perhaps QM holds an answer too because the sudden reduction of space contraction rather than space expansion is a classical version equivalent to quantum fluctuations.
Also, why do you think even a space expansion is not possible ? (But the question is not for the particular case in the news)
-
In my opinion, space expansion is a result and not a cause. I wouldn't bet a dime on Inflation. Space expands due to local gradient in electrical and gravitational potential and due to local exchange of momentum. So space expansion is limited by the speed of light. Space might appear to expand faster than light because of time dilation, but any 2 objects cannot be causally disconnected. This is a mistake.
A photon will travel relatively faster in a void and there is no event horizon anywhere in the universe. It is not totally contrary to what you wrote.
-
You better define the conditions under they do ftl Jeffrey. It's a new idea to me.
-
You better define the conditions under they do ftl Jeffrey. It's a new idea to me.
The point is I am not saying they travel faster than light. Theoretically there are micro wormholes at the very small scale. If the particles tunnel through these wormholes it would appear that they travel faster than light. Yet it is the environment at the poles of the black hole that enlarge these wormholes so that the tunneling can happen. It then looks like the angle of orientation is causing the effect.
-
Damn man, I don't f*ng know :)
you're no longer discussing ftl, you're discussing 'dimensions' to me.
That's totally differnt
-
Another speculation is that BH can be similar to atoms. They consist of waves orbiting around the centre. Frame dragging is very powerful but at poles it is not present. The only way the energy to exit is from poles. The BH decay can be similar to nuclear decay.
Possibly due to precession waves reach the poles. If they spiral up to the poles the circular motion transforms in a linear motion. If the wave is oriente up or down towards the poles they escape easily at speed c because the gravitational interaction cannot stop the electromagnetic waves. Speed of light is never exceeded this way.
-
Nilak, my understanding is that black holes don't suck, their gravity works the same as that of any other massive body
-
Nilak, my understanding is that black holes don't suck, their gravity works the same as that of any other massive body
From the spacetime model perspective, matter curves spacetime and that can be thought as space flowing towards an onject that has mass. The flow can accelerate up to speed c in case of blackholes.
It is the same gravity of course, but different structure bodies produce different effects on close objects trajectories.
What is different form a planet in case of the BH are the relativistic and a stronger frame dragging effects.
I think it is important to take into account relativistic increase in masses. A phenomenon that can be explained by relativity is that photons moving in parallel do not attract but those traveling antiparallel do. This has been confirmed experimentally. In case of other particles a similar thing happens. If moving parallel the gravity does not increase.
Taking these into account, I suspect BH have a nucleus of strong force waves (quarks orbiting at near c) orbiting around the center of the BH and a another shell of electromagnetic waves or electrons orbiting at a larger radius. The electrons are accelerated by extreme frame dragging at near c, on the outer shell.
Inside the nucleus a relatistic mass effect can happen. Because the quarks could move at near c, they only have relativistic mass like photons. The waves on one side of the orbit attract those at the 180 degrees on the orbit. Most probably the greatest amount of gravity is produced by the relativistic motion of quarks (strong force field waves) while spinning and not by their value of rest mass.
These are only my speculative ideas, the reality could be totally different, but what is clear is that BH or any planet are more than simple massive objects.
P.S.
It is likely that strong / weak forces to have fundamentally electromagnetic origin. In that case it is a single shell of the BH, comprising all sorts particles orbiting at near c (elongated helixes). Most of these particles are turned into various extreme high frequency EM waves (photon geometry). This is the optimum way to compress energy. This way the shell becomes extremely thin and gravitational effect is maximum.
-
Not questioning you reasoning, Nilak, just wondering about the terminology.
http://sciencequestionswithsurprisinganswers.org/mobile/2012/12/16/how-can-there-be-anything-left-in-the-universe-dont-black-holes-suck-everything-in/
-
Not questioning you reasoning, Nilak, just wondering about the terminology.
http://sciencequestionswithsurprisinganswers.org/mobile/2012/12/16/how-can-there-be-anything-left-in-the-universe-dont-black-holes-suck-everything-in/
Yes, Bill S, it is a terminology issue. That article anyway expalains the BH at an extremely simplified level. Anyway when thinking about space being sucked into the BH, the effect is simple newtonian gravity. It doesn't mean all object fall into the BH. They can enter orbit the same way. Space falls bu object don't necessarily. The idea of spacetime is that space moves and it is not a force but the effect is almost the same as newtonian gravity. GR however can explain more things that happen (rotating object gravity effect and relativistic mass increase). Anyway I don't agree the spacetime explanation of gravity.
In my opinion, if a BH has increased frame dragging due to increased angular velocity, it can make object entering into orbit easier rather than fall in because those that approach straight are deviated in the rotation direction.
There is more. The objects approaching the horizon spin at increasingly high speed thus the gravity effect between the shell of the horizon is reduced gradually to almost zero. What continues to exert the pull towards the centre of the BH is the gravity force from the horizon on the other side of the black hole.
-
This seems to support my idea:
http://www.nature.com/news/ligo-black-hole-echoes-hint-at-general-relativity-breakdown-1.21135?WT.ec_id=NEWS-20161215&spMailingID=52998738&spUserID=MjgzNDMxNjU2ODIS1&spJobID=1063046368&spReportId=MTA2MzA0NjM2OAS2