New insights found in black hole collisions

March 27, 2015, University of Cambridge
Black Holes Go 'Mano a Mano.' Credit: NASA, Chandra, 10/06/09

New research provides revelations about the most energetic event in the universe—the merging of two spinning, orbiting black holes into a much larger black hole.

An international team of astronomers, including from the University of Cambridge, have found solutions to decades-old equations describing what happens as two spinning black holes in a binary system orbit each other and spiral in toward a collision.

The results, published in the journal Physical Review Letters, should significantly impact not only the study of black holes, but also the search for elusive – a type of radiation predicted by Einstein's theory of general relativity – in the cosmos.

Unlike planets, whose average distance from the sun does not change over time, general relativity predicts that two black holes orbiting around each other will move closer together as the system emits gravitational waves.

"An accelerating charge, like an electron, produces electromagnetic radiation, including ," said Dr Michael Kesden of the University of Texas at Dallas, the paper's lead author. "Similarly, any time you have an accelerating mass, you can produce gravitational waves."

The energy lost to gravitational waves causes the black holes to spiral closer and closer together until they merge, which is the most energetic event in the universe, after the big bang. That energy, rather than going out as visible light, which is easy to see, goes out as gravitational waves, which are much more difficult to detect.

Illustration of two rotating black holes in orbit. Both, the black hole spins (red arrows) and the orbital angular momentum (blue arrow) precess about the total angular momentum (grey arrow) in a manner that characterizes the black-hole binary system. Gravitational waves carry away energy and momentum from the system and the orbital plane (light blue) tilts and turns accordingly. Credit: Graphic by Midori Kitagawa

While Einstein's theories predict the existence of gravitational waves, they have not been directly detected. But the ability to 'see' gravitational waves would open up a new window to view and study the universe.

Optical telescopes can capture photos of visible objects, such as stars and planets, and radio and infrared telescopes can reveal additional information about invisible energetic events. Gravitational waves would provide a qualitatively new medium through which to examine astrophysical phenomena.

"Using gravitational waves as an observational tool, you could learn about the characteristics of the black holes that were emitting those waves billions of years ago, information such as their masses and mass ratios, and the way they formed" said co-author and PhD student Davide Gerosa, of Cambridge's Department of Applied Mathematics and Theoretical Physics. "That's important data for more fully understanding the evolution and nature of the universe."

Later this year, upgrades to the Laser Interferometer Gravitational-Wave Observatory (LIGO) in the US and VIRGO in Europe will be completed, and the first direct measurements of gravitational waves may be just around the corner. Around the same time, the LISA Pathfinder mission will be launched as a test mission for establishing a of unprecedented sensitivity in space.

"The equations that we solved will help predict the characteristics of the gravitational waves that LIGO would expect to see from binary black hole mergers," said co-author Dr Ulrich Sperhake, who, along with Gerosa, is also a member of Cambridge's Centre for Theoretical Cosmology. "We're looking forward to comparing our solutions to the data that LIGO collects."

The equations the researchers solved deal specifically with the spin angular momentum of binary black holes and a phenomenon called precession.

"Like a spinning top, black hole binaries change their direction of rotation over time, a phenomenon known as precession," said Sperhake. "The behaviour of a these black hole spins is a key part of understanding their evolution."

Just as Kepler studied the motion of the earth around the sun and found that orbits can be ellipses, parabola or hyperbolae, the researchers found that black hole binaries can be divided into three distinct phases according to their rotation properties.

The researchers also derived equations that will allow statistical tracking of such spin phases, from black hole formation to merger, far more efficiently and quickly than was possible before.

"With these solutions, we can create computer simulations that follow black hole evolution over billions of years," said Kesden. "A simulation that previously would have taken years can now be done in seconds. But it's not just faster. There are things that we can learn from these simulations that we just couldn't learn any other way."

"With these tools, new insights into the dynamics of will be unveiled," said Gerosa. "Gravitational wave signals can now be better interpreted to unveil mysteries of the massive universe."

Explore further: New insight found in black hole collisions

More information: "Effective Potentials and Morphological Transitions for Binary Black Hole Spin Precession" Phys. Rev. Lett. 114, 081103 – Published 24 February 2015. dx.doi.org/10.1103/PhysRevLett.114.081103

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TopCat22
1.8 / 5 (5) Mar 27, 2015
If as you approach the event horizon time slows down to a standstill till infinity ... how can two black holes ever merge in the lifetime of the universe (past present and future) ... Also the same holds true for anything falling into a black hole.... it will take an infinite amount of time relative to everything outside of the black hole for mergers and accretion to happen.

I think the making of a black hole and the growth of a black hole are not consistent with the relativity of time approaching the black ... why does no one ever talk about this glaring contradiction.

Also the failure of detecting gravity waves also may relate to the space time around the BHs generating them is so slow that it will take many times the age of the universe to get to space time flowing as a more realistic rate to be detectable
OdinsAcolyte
1 / 5 (4) Mar 27, 2015
I think time and gravity have nothing to do with each other. Great comment TopCat.
Stevepidge
1.2 / 5 (6) Mar 27, 2015
ARGG. Charge distorts the "neutral atoms" which, by Assis, in aggregate cause the force of gravity. Lots of charge means lots of distortion, small charge means small distortion.

http://www.ifi.un...5%29.pdf

SImple NASA experimentation demonstrating charge driven orbits

http://www.youtub...youtu.be
denglish
4.6 / 5 (10) Mar 27, 2015
TopCat22, time does not stop for someone approaching the event horizon. Time dilation only applies to a distant observer.

OdinsAcolyte, my understanding of GR tells me that time and gravity are very much intertwined.
TopCat22
2 / 5 (8) Mar 27, 2015
denglish .... we here are distant observers.

From our vantage point and perspective no black holes can ever have collided and nothing can ever have made it all the way into a black hole for the entire life of the universe ... into the future or back in time to the big bang itself. Whatever massive black holes exist today had to have be created at the big bang since nothing could have merged to make them. Likewise we should see stellar black holes as very small but very bright objects with the light of the supernova fixed in slow motion time stop just before falling past the event horizon. Nothing can go past into the event horizon because time will be dilated to infinity slow.
I Have Questions
3.7 / 5 (6) Mar 27, 2015
TopCat22

The faster you go the slower time passes. A photon leaving the sun traveling at the speed of light takes eight minutes to reach earth but from the photons point of view it arrives at exactly the same time as it departed, from the point of view of the observer on earth it takes eight minutes.
denglish
4.4 / 5 (7) Mar 27, 2015
TopCat, you should do some research on GR. It is not intuitive, so definitely requires some focused learning.
Night Rider
1 / 5 (4) Mar 27, 2015
TopCat22

Time stops at the singularity, not at the event horizon.
zlatuska
5 / 5 (5) Mar 27, 2015
prEcession, not prOcession!
denglish
4.3 / 5 (6) Mar 27, 2015
Night Rider, you are wrong. Time never stops, but it certainly slows. Inside the EH, we have no idea what is happening at the singularity.

At the point of watching someone enter the EH, we see them red-shift into oblivion, which means they will fade from view; it will take a long time.
arom
Mar 28, 2015
This comment has been removed by a moderator.
Shootist
1 / 5 (4) Mar 28, 2015
Night Rider, you are wrong. Time never stops, but it certainly slows. Inside the EH, we have no idea what is happening at the singularity.

At the point of watching someone enter the EH, we see them red-shift into oblivion, which means they will fade from view; it will take a long time.


long time . . . yeah lifetime of the universe long.
Shootist
1 / 5 (3) Mar 28, 2015
"An accelerating charge, like an electron, produces electromagnetic radiation, including visible light waves," said Dr Michael Kesden of the University of Texas at Dallas, the paper's lead author. "Similarly, any time you have an accelerating mass, you can produce gravitational waves."


Anyway according Maxwell equation, electromagnetic radiation wave require some prpagation medium to work. But to Eienstein relativity, space is an empty void so it is hard to visualize how gravity wave could propagate .....

http://www.vacuum...=7〈=en


by warping space-time.
Reg Mundy
2.7 / 5 (7) Mar 28, 2015
Later this year, upgrades to the Laser Interferometer Gravitational-Wave Observatory (LIGO) in the US and VIRGO in Europe will be completed, and the first direct measurements of gravitational waves may be just around the corner.

Or maybe just around the bend.
Maybe a tiny percentage of the money could be used for exploring alternatives to gravity waves?
TopCat22
1 / 5 (4) Mar 28, 2015
TopCat, you should do some research on GR. It is not intuitive, so definitely requires some focused learning.


Yes research in general relativity is important... and that is why I was able to make my statement about black holes merging and growing.

Also time is dilated to infinity at the event horizon. Time is irrelevant inside the event horizon and becomes nonsensical at the singularity
TopCat22
2.3 / 5 (6) Mar 28, 2015
TopCat22

The faster you go the slower time passes. A photon leaving the sun traveling at the speed of light takes eight minutes to reach earth but from the photons point of view it arrives at exactly the same time as it departed, from the point of view of the observer on earth it takes eight minutes.


I don't see how this has any bearing on my statement. Unless you are helping to show that relative to us my views are correct. But relative to the black holes colliding they do collide since they are not experiencing time dilation relative to each other. This does not change the fact that we here on planet earth and anyone anywhere in the universe can never see black holes collide and grow. You could only see them do this from outside of our spacetime universe
TopCat22
2.6 / 5 (5) Mar 28, 2015
This observation of the time dilation at the event horizon also shown that Hawking Radiation would be subject to the same thing and never reach an observer because of time dilation. It would take an infinite amount of time for the radiation to travel from the edge of the event horizon to one millimeter away. We might as well assume that Hawking Radiation does not exist in our universes space time.
denglish
3.9 / 5 (7) Mar 28, 2015
OMG.

First I thought it was ignorance, but now I see what's happening. You guys are saying GR isn't real. I challenge you to go to a referree'd physics forum and try to disprove GR.
Arginx
2.3 / 5 (3) Mar 28, 2015
OMG.

First I thought it was ignorance, but now I see what's happening. You guys are saying GR isn't real. I challenge you to go to a referree'd physics forum and try to disprove GR.


I see that you are one of this 'believers' who don't think, they just believe in '1 true truth'.
Maybe GR have some holes and maybe TopCat22 found just one.
In my opinion his thinking is right but I need check few formulas 1st to be sure.
TopCat22
2 / 5 (4) Mar 28, 2015
OMG.

First I thought it was ignorance, but now I see what's happening. You guys are saying GR isn't real. I challenge you to go to a referree'd physics forum and try to disprove GR.


Yes think you are right that it is your ignorance ... no one is attempting to prove or disprove general relativity. General Relativity is the thing that is saying what I am saying. Because of General Relativity we as observers inside this space time can not ever experience two black holes merging or a black hole growing because the time dilation would make these events take an infinite amount of time relative to us... although they would occur relative to the black holes that are so doing ... to us it would appear to happen simultaneously with the end of our time.

Learn a little more about GR or think some of it through ... its all relative
denglish
3.7 / 5 (6) Mar 28, 2015
This observation of the time dilation at the event horizon also shown that Hawking Radiation would be subject to the same thing and never reach an observer because of time dilation. It would take an infinite amount of time for the radiation to travel from the edge of the event horizon to one millimeter away. We might as well assume that Hawking Radiation does not exist in our universes space time.

Time dilation is not an observation it is a calculation.

Hawking radiation cannot be observed because it is causually disconnected from the outside world by the event horizon.

Assuming is the root cause of your erroneous posts.
denglish
4.2 / 5 (5) Mar 28, 2015


Learn a little more about GR or think some of it through ... its all relative

Gravitational waves (a prediction of GR) are created by the perturbations of gravity by orbiting bodies.

These perturbations are outside of the EH, and radiate further outward.

Again. Because it cannot be observed does not mean it cannot happen.
cantdrive85
2.1 / 5 (7) Mar 28, 2015
New research provides revelations


An international team of astronomers, including from the University of Cambridge, have found solutions to decades-old equations


"Today's scientists have substituted mathematics for experiments, and they wander off through equation after equation, and eventually build a structure which has no relation to reality." Nikola Tesla

BH's have no relation to reality!
cantdrive85
2.1 / 5 (7) Mar 28, 2015
OMG.

First I thought it was ignorance, but now I see what's happening. You guys are saying GR isn't real. I challenge you to go to a referree'd physics forum and try to disprove GR.


You cannot disprove that which is non-falsifiable.
denglish
4.4 / 5 (7) Mar 28, 2015
New research provides revelations


An international team of astronomers, including from the University of Cambridge, have found solutions to decades-old equations


"Today's scientists have substituted mathematics for experiments, and they wander off through equation after equation, and eventually build a structure which has no relation to reality." Nikola Tesla

BH's have no relation to reality!

It is a wise quote.

So, what are we observing if not massive gravity wells? As we get better at observation, GR predictions are being realized as reality. Observation of gravitational waves may be the next big proof of GR.
Arginx
1 / 5 (1) Mar 28, 2015
answer for this dilemma: http: // arxiv.org/pdf/1209.2113.pdf

But in my opinion this answer isn't good to. It's simple skip question how can BH grown if nothing (in theory) can reach even horizon. So 'gap' in this theory still exist.. we must remember that 'observer' of event horizon also exist inside of BH. So also BH can't evaporate in infinite time. ... I need do more research and ask others about that...
Arginx
1 / 5 (1) Mar 28, 2015


Learn a little more about GR or think some of it through ... its all relative

Gravitational waves (a prediction of GR) are created by the perturbations of gravity by orbiting bodies.

These perturbations are outside of the EH, and radiate further outward.

Again. Because it cannot be observed does not mean it cannot happen.


Srsly.. maybe start speak about 'little dwars which move particles'.

like you said:
Again. Because it cannot be observed does not mean it cannot happen.
denglish
4.2 / 5 (5) Mar 28, 2015
answer for this dilemma: http: // arxiv.org/pdf/1209.2113.pdf

But in my opinion this answer isn't good to. It's simple skip question how can BH grown if nothing (in theory) can reach even horizon. So 'gap' in this theory still exist.. we must remember that 'observer' of event horizon also exist inside of BH. So also BH can't evaporate in infinite time. ... I need do more research and ask others about that...

You need to understand that it is all about frame of reference.

In the frame of the infaller, everything is happening in real time.

In the frame of the observer, things are time-dilated.

This does not mean that something is not happening. it simply means that things are being perceived differently from different frames of reference.
TopCat22
2 / 5 (4) Mar 28, 2015


Learn a little more about GR or think some of it through ... its all relative

Gravitational waves (a prediction of GR) are created by the perturbations of gravity by orbiting bodies.

These perturbations are outside of the EH, and radiate further outward.

Again. Because it cannot be observed does not mean it cannot happen.


You are a funny fellow ... I think you actually agree with me but want to argue against just the same.

No one said they do not happen ... what I said is that because of the time dilation relative to an observer we cannot ever see it or measure it. Relative to the black hole the event do occur in their time. To us it occurs only at the end of our time because of relatively and dilation of time
denglish
4.2 / 5 (5) Mar 28, 2015


Learn a little more about GR or think some of it through ... its all relative

Gravitational waves (a prediction of GR) are created by the perturbations of gravity by orbiting bodies.

These perturbations are outside of the EH, and radiate further outward.

Again. Because it cannot be observed does not mean it cannot happen.


Srsly.. maybe start speak about 'little dwars which move particles'.

like you said:
Again. Because it cannot be observed does not mean it cannot happen.


Start here:

http://en.wikiped...nal_wave
denglish
4.2 / 5 (5) Mar 28, 2015
You are a funny fellow ... I think you actually agree with me but want to argue against just the same.

No one said they do not happen ... what I said is that because of the time dilation relative to an observer we cannot ever see it or measure it. Relative to the black hole the event do occur in their time. To us it occurs only at the end of our time because of relatively and dilation of time


I am correcting your misconceptions.

In the context of this article, you need to understand what gravitational waves are. Then, you should look at some simulations of massive body collisions. There are lots on Youtube.

TopCat22
1 / 5 (3) Mar 28, 2015
lets think about a black hole being made .... the star goes supernova and starts to collapse ... at some point an event horizon is created somewhere between the center and the farthest edge of the supernova....

whatever is inside the event horizon is now gone... but all the rest that is still outside of the event horizon becomes subject to time dilation that slow to infinity at the event horizon. All of that light and mater and energy remains there outside forever relative to us never falling in.

A black hole then looks just like a star. Bright from the light and energy that is frozen outside of the event horizon.
denglish
4.2 / 5 (5) Mar 28, 2015
lets think about a black hole being made .... the star goes supernova and starts to collapse ... at some point an event horizon is created somewhere between the center and the farthest edge of the supernova....

whatever is inside the event horizon is now gone... but all the rest that is still outside of the event horizon becomes subject to time dilation that slow to infinity at the event horizon. All of that light and mater and energy remains there outside forever relative to us never falling in.

A black hole then looks just like a star. Bright from the light and energy that is frozen outside of the event horizon.

No, you are totally wrong.

Start here:

http://en.wikiped...ack_hole
TopCat22
1 / 5 (3) Mar 28, 2015
You are a funny fellow ... I think you actually agree with me but want to argue against just the same.

No one said they do not happen ... what I said is that because of the time dilation relative to an observer we cannot ever see it or measure it. Relative to the black hole the event do occur in their time. To us it occurs only at the end of our time because of relatively and dilation of time


I am correcting your misconceptions.

In the context of this article, you need to understand what gravitational waves are. Then, you should look at some simulations of massive body collisions. There are lots on Youtube.



I understand gravity waves enough for my comments ...

... black hole collisions can not ever occur relative to us as observers because a collision will take forever to happen due to time dilation as they get closer together. The black holes do collide relative to each other but not so we can ever see or tell in our entirety of time
denglish
4.2 / 5 (5) Mar 28, 2015
I understand gravity waves enough for my comments ...

... black hole collisions can not ever occur relative to us as observers because a collision will take forever to happen due to time dilation as they get closer together. The black holes do collide relative to each other but not so we can ever see or tell in our entirety of time


If you think it can't be observed, then you have no idea what gravitational waves are thought to be.

You need to understand that events that happen away from black holes, but that are the results of black hole gravity, are observed. As we get closer to the EH, we realize that due to time dilation (which is an optical illusion), we are seeing things that happened a long time ago.

TopCat22
1 / 5 (4) Mar 28, 2015
what I am thinking now is that all of the supermassive black holes at the centers of all galaxies must have all been created first before our timeline started.

Otherwise they could not exist within our timeline by aggregating inside it.
denglish
4.2 / 5 (5) Mar 28, 2015
what I am thinking now is that all of the supermassive black holes at the centers of all galaxies must have all been created first before our timeline started.

Otherwise they could not exist within our timeline by aggregating inside it.

Nonsense.

Arginx
1 / 5 (4) Mar 28, 2015
I think (sure) that denglish isn't to smart at all. So any attempt to discuss with him, don't have any sense at all. He can't or don't want understand what we talking here about.

His 'proof' that he is 'right' .. others are wrong... exist only in theory.. only for prove that GR is correct. But THERE IS NO PROOF or FACT which would give us, a basis to claim that such waves exist. So this is a never ending story. Like I said at beginning.. he is one of this 'believers'.

Even if gravity waves exist, but in my opinion they are not. They can't 'fill' this 'gap' about event horizon. So conclusion is simple.. our knowledge about BH and other observations of 'space behavior' is wrongly interpreted.
denglish
4.2 / 5 (5) Mar 28, 2015
I think (sure) that denglish isn't to smart at all. So any attempt to discuss with him, don't have any sense at all. He can't or don't want understand what we talking here about.

His 'proof' that he is 'right' .. others are wrong... exist only in theory.. only for prove that GR is correct. But THERE IS NO PROOF or FACT which would give us, a basis to claim that such waves exist. So this is a never ending story. Like I said at beginning.. he is one of this 'believers'.

Even if gravity waves exist, but in my opinion they are not. They can't 'fill' this 'gap' about event horizon. So conclusion is simple.. our knowledge about BH and other observations of 'space behavior' is wrongly interpreted.

Nonsense.
Arginx
1 / 5 (4) Mar 28, 2015

You need to understand that events that happen away from black holes, but that are the results of black hole gravity, are observed. As we get closer to the EH, we realize that due to time dilation (which is an optical illusion), we are seeing things that happened a long time ago.


This is proof for me, that he isn't know what he talking about.
...time dilation is a illusion.. Hello is anybody home?! Do you heard about GPS?! So check now how it works...
Only illusion is your knowledge about physics denglish.
Arginx
1 / 5 (4) Mar 28, 2015
In fact, time dilation is confirmed by a number of experiments. In the Hafele-Keating experiments of 1971, atomic clocks (which are very precise) were flown on airplanes traveling in opposite directions. The time differences shown on the clocks, as a result of their relative motion, precisely matched the predictions from relativity.


It's for you Mr. Illusion. :p
Arginx
1 / 5 (3) Mar 28, 2015
from 1st link
numerous conflicts have arisen, especially in places where both theories apply — such as black holes and event horizons. [/p]

..I do not need to say more..
denglish
4.2 / 5 (5) Mar 28, 2015

You need to understand that events that happen away from black holes, but that are the results of black hole gravity, are observed. As we get closer to the EH, we realize that due to time dilation (which is an optical illusion), we are seeing things that happened a long time ago.


This is proof for me, that he isn't know what he talking about.
...time dilation is a illusion.. Hello is anybody home?! Do you heard about GPS?! So check now how it works...
Only illusion is your knowledge about physics denglish.

Optical illusion.

Nonsense.
denglish
4.2 / 5 (5) Mar 28, 2015
also you should read this.. :p

http: // http://www.extrem...ck-holes

So maybe next time, you do some 'research' before you post another 'nonsense' comment. :p

Wow, you are floundering something awful.

Look. Don't be offended. Fact is, you have no idea what you're talking about.
denglish
4.2 / 5 (5) Mar 28, 2015
In fact, time dilation is confirmed by a number of experiments. In the Hafele-Keating experiments of 1971, atomic clocks (which are very precise) were flown on airplanes traveling in opposite directions. The time differences shown on the clocks, as a result of their relative motion, precisely matched the predictions from relativity.


It's for you Mr. Illusion. :p

I never denied Time Dilation. In fact, I have been trying to explain it to you and your friends.

The OP said that it is impossible to observe black hole collision because of time dilation, and thus the collisions never happen. This is false, and other people that read these forums depend on other readers to expose nonsense in order to not be mis-led by hare-brained speculation.
Arginx
1 / 5 (3) Mar 28, 2015
So 'enlighten' me.. explain this concept of 'optical illusion' of time dilatation.
Because I really want to know what it is.
antialias_physorg
5 / 5 (5) Mar 28, 2015
At the point of watching someone enter the EH, we see them red-shift into oblivion, which means they will fade from view; it will take a long time.

Only technically, as the amount of photons the in-falling object emits doesn't suddenly increase when it nears the event horizon. The number of such photons drops drastically the longer the observation (as time is stretched for the object from the point of the outside observer the number of registered photons is equally divided. And since the photons are quanta there is a time when the last photon will be registered).
I'd wager the amount of time until an in-falling object becomes invisible (i.e. until that last photon is registered) is rather short.

The thing an outside observer doesn't see is the object crossing the event horizon. But that doesn't mean the object stays visible forever outside it.
(cont)
denglish
4 / 5 (4) Mar 28, 2015
So 'enlighten' me.. explain this concept of 'optical illusion' of time dilatation.
Because I really want to know what it is.

The optical illusion is dependent on frames of reference. What I mean is, what someone experiences will depend on where they are.

For the person falling into a black hole, time moves normally for them. They fall into the event horizon with no delay.

For the person observing it from afar, they never see the in-faller enter the event horizon - due to time dilation. The in-faller will appear to stop just before the event horizon, and will eventually fade from view- an effect know as "red-shifting" - the light waves get longer and longer.

So, to the in-faller, and to the black hole, the event happens in real time. To the observer, the event never happens. Thus, the observer is experiencing an optical illusion. It looks like it never happened, but in fact it did. It all depends on where you see the event from.

antialias_physorg
5 / 5 (4) Mar 28, 2015
(cont)...so we have to distingusish here between the photons that the observer registered - which were all emitted by the object before crossing the event horizon) and the object itself (which may have long ago fallen in - even though the observer doesn't see that as the photons from before the crossing are still en-route to him)
denglish
3.7 / 5 (3) Mar 28, 2015
At the point of watching someone enter the EH, we see them red-shift into oblivion, which means they will fade from view; it will take a long time.

Only technically, as the amount of photons the in-falling object emits doesn't suddenly increase when it nears the event horizon. The number of such photons drops drastically the longer the observation (as time is stretched for the object from the point of the outside observer the number of registered photons is equally divided. And since the photons are quanta there is a time when the last photon will be registered).
I'd wager the amount of time until an in-falling object becomes invisible (i.e. until that last photon is registered) is rather short.

The thing an outside observer doesn't see is the object crossing the event horizon. But that doesn't mean the object stays visible forever outside it.
(cont)

Yes, but I would accept your wager. :-) The amount of time dilation at the EH is extreme.
denglish
3.7 / 5 (3) Mar 28, 2015
(cont)...so we have to distingusish here between the photons that the observer registered - which were all emitted by the object before crossing the event horizon) and the object itself (which may have long ago fallen in - even though the observer doesn't see that as the photons from before the crossing are still en-route to him)

Right. Thus the optical illusion analogy is correct, yes?
TopCat22
1 / 5 (1) Mar 28, 2015

The optical illusion is dependent on frames of reference. What I mean is, what someone experiences will depend on where they are.

For the person falling into a black hole, time moves normally for them. They fall into the event horizon with no delay.

For the person observing it from afar, they never see the in-faller enter the event horizon - due to time dilation. The in-faller will appear to stop just before the event horizon, and will eventually fade from view- an effect know as "red-shifting" - the light waves get longer and longer.

Your optical illusion argument is hogwash.
You fail to understand basic General Relativity.
To the observer it does not ever happen in their timeline.
To the fallen is does happen but in their timeline only.
NO ILLUSIONS ... That's why its called relative. Both are correct to themselves but not to each other
denglish
3.7 / 5 (3) Mar 28, 2015

The optical illusion is dependent on frames of reference. What I mean is, what someone experiences will depend on where they are.

For the person falling into a black hole, time moves normally for them. They fall into the event horizon with no delay.

For the person observing it from afar, they never see the in-faller enter the event horizon - due to time dilation. The in-faller will appear to stop just before the event horizon, and will eventually fade from view- an effect know as "red-shifting" - the light waves get longer and longer.

Your optical illusion argument is hogwash.
You fail to understand basic General Relativity.
To the observer it does not ever happen in their timeline.
To the fallen is does happen but in their timeline only.
NO ILLUSIONS ... That's why its called relative. Both are correct to themselves but not to each other

Nonsense.
Arginx
1 / 5 (1) Mar 28, 2015
ok.. I have read so many publications about BH and event horizon paradox, so now I can be sure that explanation of EH by denglish it's total tosh.
check in google: firewall paradox, information paradox

There is 2 major publication in 2014 y., that claim is BH in 'well know form' can't exist at all.
One of them denied of existences in general. The second suggest that GR is partially wrong, because BH defined by GR can't exist. So now 'world of science' looking for new definition of BH.
www.nytimes.com/2...tml?_r=0
...
Anyway I feel obligated to answer to this 'optical illusion' matter.

1. optical illusion - by def. is:
The information gathered by the eye is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus source


antialias_physorg
5 / 5 (3) Mar 28, 2015
Yes, but I would accept your wager. :-) The amount of time dilation at the EH is extreme.

If stretching is merely 100% then the object is already half as dim. At the extreme stretching we get near the event horizon the dimming will be phenomenal in no time. Note also that the area where this extreme stretching happens is actually fairly small (for a sun-mass black hole it would be a couple of kilometers at most). So the number of photons that are emitted by the object while in that region is pretty low (as it will be moving at a fair clip).
Right. Thus the optical illusion analogy is correct, yes?

Yes.

What the observer sees is stuff that (from the point of view of the falling object) has long ago passed. It's like hearing the supersonic bang...but in reality you know the plane is already way beyond the point where the bang comes from when you hear it.
Arginx
1 / 5 (1) Mar 28, 2015
So in OUR matter it can't be any form of 'optical illusion'. Because as definitions SAID...
does not tally with a physical measurement
.

2. You can OBSERVE object only if one or both event takes place.
a - photons can reflect from observed object
b - observed object emits photons

So if I can OBSERVE object falling to EH.. that means that object is still above EH. And because formula which describes EH based on GR. CLEARLY SAID that from observer point of view, time dilatation going to infinity. Which, means that from the point of falling object all observed universe SHOULD FREEZE, before it cross EH.
It's BASIC PRINCIPE of GR that you can take any reference system, and yours observation from this 'other' system will be the same. Because you can't said from your 'rs' that you move instead observed 'system'. From you local point of view, everything around moving faster.. NOT YOU. And this is principle of GR !! It's also defines that speed of light is const !!
antialias_physorg
5 / 5 (3) Mar 28, 2015
So in OUR matter it can't be any form of 'optical illusion'. Because as definitions SAID...


does not tally with a physical measurement

Since you're only seeing echos of the past it is an illusion in that sense. The object falls through in a finite time for the outside observer and ab observer riding along with it - there's no doubt about it.

Think about the opposite: If nothing could fall through an event horizon then black holes themseves could never from. it's not like a lot of matter gets on top of each other and suddenly forms an 'impenetrable wall' at the event hroizon. The event horizon is only a defined region in space (which grows over time as more stuff falls in and can even deform due to rotation - viz. the ergosphere).
There's no sudden break in the laws of physics from inside to outside the event horizon.
Arginx
not rated yet Mar 28, 2015
Yes, but I would accept your wager. :-) The amount of time dilation at the EH is extreme. ]
If stretching is merely 100% then the object is already half as dim. At the extreme stretching we get near the event horizon the dimming will be phenomenal in no time.


omg.. another bunk.. you people REALLY don't understand of basic and you try explain such complicated thing as BH?! hahahah

Tell me Mr. Mastermind .. WHY this object should DIM??! WHY?!
If his density lower or he absorbs more light? And if so.. can you write this formula which describes it?

Please... Stop making all this not supported by any evidence explanations. And don't repeat mindlessly 'facts', that you don't even understand and what you talking about.
It's like talking with a parrot.

All FACTS about BH and EH you can find via google. Read it ... and do what ever...
For me this conversation is over.
Arginx
not rated yet Mar 28, 2015
Since you're only seeing echos of the past it is an illusion in that sense.


Just start writing fantasy book or book for children. So you can explain, any of physical phenomenon by what ever you said. In fairy tale you can create WHAT EVER YOU WANT. :-D
Illusions.. echos.. little pink pony who can run faster then light. :-D
And you don't need prove any of that!! Like you and Mr. Illusion, doing right now.. :-)
denglish
3 / 5 (2) Mar 28, 2015
ok.. I have read so many publications about BH and event horizon paradox, so now I can be sure that explanation of EH by denglish it's total tosh.
check in google: firewall paradox, information paradox

There is 2 major publication in 2014 y., that claim is BH in 'well know form' can't exist at all.
One of them denied of existences in general. The second suggest that GR is partially wrong, because BH defined by GR can't exist. So now 'world of science' looking for new definition of BH.
http://www.nytime...tml?_r=0
...
Anyway I feel obligated to answer to this 'optical illusion' matter.

1. optical illusion - by def. is:
The information gathered by the eye is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus source



It is rare when one offers evidence of one's own refutation. Well played.
denglish
3 / 5 (2) Mar 28, 2015
Although it seems self-defeating, in a way I am proud to be on this forum so that the people who taught me don't need to be.
Bob Osaka
1 / 5 (2) Mar 28, 2015
Again with yet another: "the discovery of gravitational waves may be just around the corner," prognostications. Let us know when you find the corner of the observable universe.
The article is a little confusing and not very well written. For example, do spinning tops change the direction of their rotation? Isn't a procession a religious parade?
Simulations aside, the clearest real world example of merging black holes is quasar PG 1302-102 which may be observed in a million years or so. For those without such patience, suggest looking into the corrugation of the Milky Way. Remember the propagation of gravitational waves is toward the center of the mass not away from it. Often erroneous, backward examples of a stone dropped in water are used. Also, that they may not be detectable in the EM spectrum and may only be described in dimensionless units such as steradians.
One should never overestimate how much they are learning from video games.
adave
not rated yet Mar 28, 2015
For some observer time the black hole will have multiple singularities. Is the singularity in the geometric center or just past the horizon? As the event horizons finally collide from an elliptic orbit won't the relativistic frames merge and space be distorted as they pull apart? Are they not quantum entangled by a wormhole? Since we can't seem to explain the size of some black holes wouldn't it be interesting if they had billions of singularities? Can singularities orbit one another past the event horizon so that they never reach the center of rapidly changing space time curvature? Would a collision leave mini black hole eddies in their wake?
I Have Questions
1 / 5 (1) Mar 29, 2015
TopCat22

I don't see how this has any bearing on my statement. Unless you are helping to show that relative to us my views are correct. But relative to the black holes colliding they do collide since they are not experiencing time dilation relative to each other. This does not change the fact that we here on planet earth and anyone anywhere in the universe can never see black holes collide and grow. You could only see them do this from outside of our spacetime universe


Well you said this and I could see you needed some help so...

From our vantage point and perspective no black holes can ever have collided and nothing can ever have made it all the way into a black hole for the entire life of the universe
antialias_physorg
5 / 5 (3) Mar 29, 2015

Just start writing fantasy book or book for children. So you can explain, any of physical phenomenon by what ever you said. In fairy tale you can create WHAT EVER YOU WANT.

It's notreally hard to understand. Or do you also deny that the comsic microwave background is the light of the big bang that is reaching us now? Because the big bang isn't happeing right now. It happened a couple of billion years ago.

That we can see something now doesn't mean it's happening now. Just look at the night sky. We see everything the way it was at some point in the past depending on how far away it is. Does that mean that's the state of things - if you could teleport there - right now? No.
Arginx
not rated yet Mar 29, 2015
Your example it's right.. but not in this case.
Following after you.. if distant star explode (like 10 light,y far away). After 10 y. I still be able watching this star. In our case, this time will be FOR EVER !!
So tell me... it's true or false? :-)

I hope, that now you see this paradox... :-)
antialias_physorg
5 / 5 (3) Mar 29, 2015
In our case, this time will be FOR EVER !!

Exactly the same reason why you will be able to see the big bang radiation for ever (at an ever decreasing intensity).
The space is stretching out, so there are always some photons that reach you no matter how long you wait*

You can go at it from yet another angle. You can calculate the time it takes for some stationary object (not in orbit) that you release at a distance from some mass to hit that mass. That is no different for a planet, a star, or a black hole. That an outside observer might see something different due to the stretching of space near black holes (or even just stars) makes no difference to what actually happens.

No paradox here.

*not exactly true, because as I mentinoed there are a limited number of photons as photons are quantized - even for the big bang afterglow...so at some point the exponential curve will drop to zero. For our infalling object into the black hole it's just the same.

TopCat22
not rated yet Mar 29, 2015
Although it seems self-defeating, in a way I am proud to be on this forum so that the people who taught me don't need to be.


denglish ... I don't think you should be too proud of who taught you the English language because you are very confused about the meaning of simple words,

An "ILLUSION" (optical or otherwise) is something that is not real. When you say Time Dilation is an Optical Illusion you are saying that it is not real.

They you go off on a tangent from there to say to study General Relativity that you say justifies your illusion (delusion).

My dear sir Time Dilation is very REAL and in no way an illusion... it is measured, allowed for, corrected and used everyday by billions of people and devices every minute around the world.

It is also the very reason I am saying that two black holes cannot merge because it takes an infinite amount of time for their event horizons to meet. As they get closer together their time slows down to a stop relative to us.
denglish
3 / 5 (2) Mar 29, 2015

My dear sir Time Dilation is very REAL and in no way an illusion... it is measured, allowed for, corrected and used everyday by billions of people and devices every minute around the world.

It is also the very reason I am saying that two black holes cannot merge because it takes an infinite amount of time for their event horizons to meet. As they get closer together their time slows down to a stop relative to us.

If something happens, but you see something else, what is that called?

Anyway, your position that time dilation prohibits events (see your first post) is ridiculous.
antialias_physorg
5 / 5 (3) Mar 29, 2015
An "ILLUSION" (optical or otherwise) is something that is not real. When you say Time Dilation is an Optical Illusion you are saying that it is not real.

Well, he's right in that, as the black hole will give us the illusion that an object never crosses the event horizon - as we can see it for all eternity slowing down but never quite crossing (ignoring the rapidly redshifting and diminishing intensity for a moment)

But what we are actually seeing is just the light emitted by it a (very) small amount of time it spends before crossing stretched out over an infinite time.
(And nothing of the time when it has crossed, as that light can't get out).

So yes: what we see isn't what actually happened. The object didn't slow down. I'd call that an optical illusion.
TopCat22
not rated yet Mar 29, 2015
I see that both of you are having trouble visualizing the basic working of general relativity and time dilation.

Both Events are True and no one is experiencing an illusion.

There are two timelines involved,

There is one timeline for the observer which is a true period of time with a beginning and an end.

There is another timeline for the infallen which is also a true period of time with its own beginning and its own end.

To one falling the event actually occurs.
To one observing the event never occurs.

It is exactly the same process by which twins will age at different rates if one goes on a trip to orbit a black hole and comes back a much younger twin.
rpaul_bauman
1 / 5 (1) Mar 29, 2015
If one starts out assuming that Generall Relativity is correct, you are wrong to start with. To prove is easy. Since GR, some 90 years ago, there are 99 newer theories on gravity, if any one were RIGHT, there would only be ONE theory. All the lateest do not even consider Dark Matter, nor singularities. And a latest, LSG (line of sight gravity) you should read.
denglish
3.7 / 5 (3) Mar 29, 2015
Wow. This place attracts some very entertaining people. The internet. WHO KNEW?!?!
TopCat22
not rated yet Mar 29, 2015
Wow. This place attracts some very entertaining people. The internet. WHO KNEW?!?!


Thanks ... and I hope you leaned something too.
denglish
4 / 5 (4) Mar 29, 2015
Wow. This place attracts some very entertaining people. The internet. WHO KNEW?!?!


Thanks ... and I hope you leaned something too.

I did learn something, thanks for demonstrating the maxim: "this guy knows just enough to be dangerous".

Finally, I think you should share your knowledge with the science community. I challenge you to come over to a real physics forum and "share your knowledge".

https://www.physicsforums.com/

Step into the Astrophysics section, and say that time dilation renders events impossible. We need to be taught by you.
rpaul_bauman
1 / 5 (1) Mar 29, 2015
Stay on physics please. Here is Dr. Moffat's MOG. based on GR, but he changes it some. MOG does not have singularities, dark matter, and includes dark energy and no Big Bang, about 5 years ago. If your argument is that GR fits all obserables, that's what EVERY theory claims. LSG is not a theory, it's a model. And it fits all obserables differently. You change one varable (L) to fit and then study the variable (L) to understand gravity. And LSG only uses the Newtonian Equation, so it is very easy to use.
antialias_physorg
5 / 5 (1) Mar 29, 2015
To one falling the event actually occurs.
To one observing the event never occurs.

Correction: for the one observing it that event is never observed.
What actually _occurs_ is only relevant in the frame of reference of the object.
rpaul_bauman
1 / 5 (1) Mar 29, 2015
Please list assumptions first. The last one assumed Special Relativity is correct. Start at the moment of the Big Bang, there is now one particle, is there SR ? That particle was "placed" there. Next that one particle starts to decay in paries. There are now 3 particles. Particles 2 and 3 are placed also some place. They did NOT move away from the first particle thru space, there is no space. Special Relativity does work yet, it's still wrong. Same for the next 10**50 particles. Are there some parts of SR that is correct ? Yes. All that happens inside a space particle uses parts of SR. Oh , this assume nothing is continuous, Another problem for GR and SR.
denglish
1 / 5 (1) Mar 29, 2015
Please list assumptions first. The last one assumed Special Relativity is correct. Start at the moment of the Big Bang, there is now one particle, is there SR ? That particle was "placed" there. Next that one particle starts to decay in paries. There are now 3 particles. Particles 2 and 3 are placed also some place. They did NOT move away from the first particle thru space, there is no space. Special Relativity does work yet, it's still wrong. Same for the next 10**50 particles. Are there some parts of SR that is correct ? Yes. All that happens inside a space particle uses parts of SR. Oh , this assume nothing is continuous, Another problem for GR and SR.

Dude, you're even more nonsensical than TopCat22.
rpaul_bauman
1 / 5 (1) Mar 29, 2015
Which proves the point when some one can not even understand the question, "Was there a first particle ?"
TopCat22
not rated yet Mar 29, 2015
To one falling the event actually occurs.
To one observing the event never occurs.

Correction: for the one observing it that event is never observed.
What actually _occurs_ is only relevant in the frame of reference of the object.


There is nothing to correct.

You are confusing yourself by trying to differentiate "observation" with "occurrence".

In General Relativity time is relative to the reference frame you are talking about.

Both events actually happen. One, the black holes do collide relative to the black holes. Two, the black holes never collide relative to the observer... the observer would have to wait forever for the collision to occur. Therefore the collision cannot ever occur in the timeline of the observer.

This is not an optical illusion to the observer. Or a failure to observe something. To the observer the event can never actually happen even if he waits from the big bang to the end of time.
denglish
3.7 / 5 (3) Mar 29, 2015
This is not an optical illusion to the observer. Or a failure to observe something. To the observer the event can never actually happen even if he waits from the big bang to the end of time.

You are wrong.

The article above describes how the collision would be observed. Gravitational waves would be created as the BHs orbit each other. That is the point of the article.

Wait. You do know that BH gravity extends beyond the EH, yes?
TopCat22
not rated yet Mar 29, 2015
you are still as wrong as ever denglish.... yes they can orbit each other as close as they like till all hell freezes over but they can not ever actually collide till the end of time as far as you are concerned as an observer.

The only way you could experience the collision is for you to first jump through the event horizon so that you are no longer an outside observer and are then part of the black hole timeline and reference frame and can then knock yourself out experiencing the collision from inside it
denglish
3 / 5 (2) Mar 29, 2015
you are still as wrong as ever denglish.... yes they can orbit each other as close as they like till all hell freezes over but they can not ever actually collide till the end of time as far as you are concerned as an observer.

The only way you could experience the collision is for you to first jump through the event horizon so that you are no longer an outside observer and are then part of the black hole timeline and reference frame and can then knock yourself out experiencing the collision from inside it

Yes or No question for you:

Does the article describe the detection of BH collision with another BH via detection of the gravitational waves created as the BHs orbit each other?

Yes or No.

denglish
1 / 5 (1) Mar 29, 2015
Which proves the point when some one can not even understand the question, "Was there a first particle ?"

Speculation is NOT science.
TopCat22
not rated yet Mar 29, 2015
That's the whole point of my post... and it may also be why we cannot detect gravitational waves.

The collisions take forever to happen from our point of view as observers.

The spacetime around them is dilated so that the gravitational waves are moving ever slower as they get closer together and may take forever to move across one millimeter of distance from the event horizon.

So in conclusion .... they say here "collision" however at best they can perceive is a very close orbit that never results in an actual collision as far as we can ever tell.

My more important point though is ... how do we get supermassive black holes and growth of black holes to happen if they cannot happen within our timeline? Are they all created simultaneously with the big bang?
denglish
3.7 / 5 (3) Mar 29, 2015
My more important point though is ... how do we get supermassive black holes and growth of black holes to happen if they cannot happen within our timeline? Are they all created simultaneously with the big bang?


Now this is weird. Dude talks about how important frames of reference are, but then posits this nonsense; absolutely no clue.

You failed to answer yes or no. I'll help you; yes. Gravitational waves emanate in all directions. "Emanate" being the key term here. The waves do not stay at the point of greatest time dilation. They move out, and can then be measured.

Just as we can observe X Rays created by accretion discs, we can, in theory (according to the article), observe gravitational waves.

D00d, you REALLY need to stop relying on your speculation and get with some knowledge. It is so laughing ironic that you continue on about frames of reference, but you don't grasp it at all.
denglish
3.7 / 5 (3) Mar 29, 2015
My more important point though is ... how do we get supermassive black holes and growth of black holes to happen if they cannot happen within our timeline? Are they all created simultaneously with the big bang?


This is how:

When a very massive star exhausts its nuclear fuel it explodes as a supernova. The outer parts of the star are expelled violently into space, while the core completely collapses under its own weight.

If the core remaining after the supernova is very massive (more than 2.5 times the mass of the Sun), no known repulsive force inside a star can push back hard enough to prevent gravity from completely collapsing the core into a black hole.

As the black hole gathers material that surrounds it (also known as accretion), that material adds to the mass of the black hole - growing it.
denglish
1 / 5 (1) Mar 29, 2015
TopCat, I see you went over to the Physics Forums. Good for you, and good luck in your journey. :)
cantdrive85
2.3 / 5 (3) Mar 29, 2015
This is how:

Nice conjecture, do you have anything but equations and theoretical speculation to support this wild claim? One bit of in situ data or some lab work (real physical research) which supports this notion?

Relativity, BH's, DM, DE, all other such nonsense, and magical fairy dust are complete fallacies. All discussions, thought, or typed word, about such topics, is an utter waste of time. This is a fact overlooked by many, and quite frankly unseeable by many due to the conditioning they have received in their "educations". This was understood by previous generations;
"...magnificent mathematical garb (Relativity) which fascinates, dazzles and makes people blind to the underlying errors. The theory is like a beggar clothed in purple whom ignorant people take for a king ... its exponents are brilliant men, but they are metaphysicists, not scientists..." Tesla, New York Times, July 11, 1935, p23, c8

And there are others;

http://vixra.org/abs/1308.0073
yyz
4.4 / 5 (7) Mar 29, 2015
@cantdrive,

How nice of you to quote Tesla lamenting scientists relying on mathematics to prove their theories and then link to Crother's *purely mathematical* argument against black holes and GR. My irony meter just esploded!
rpaul_bauman
1 / 5 (2) Mar 29, 2015
Thanks; there are NO black boles. If time STOPS at the EH how would mass get inside. or where does the mass go at the singularity, etc ? As stated earlier MOG starts with GR and does not have Black Holes, a lot of new theories on gravoty do the same thing. 100 and they are ALL wrong which is why there are 100 theories ! If you don't start out right the theory is useless. So what is space ?? If one states space IS NOT a particle, you have said what space is not, state what space is !!
cantdrive85
1.8 / 5 (5) Mar 29, 2015
@cantdrive,

How nice of you to quote Tesla lamenting scientists relying on mathematics to prove their theories and then link to Crother's *purely mathematical* argument against black holes and GR. My irony meter just esploded!

How else would one dismantle a *purely mathematical* hypothesis?
yyz
5 / 5 (5) Mar 29, 2015
"...magnificent mathematical garb (Crothers' mathematical 'hypotheses') which fascinates, dazzles and makes ignorant people blind to the underlying errors. The 'hypotheses' are like a beggar clothed in purple whom ignorant people take for a king(Crothers) ... its exponents are college dropouts, but they are metaphysicists, not scientists..."

Fixed that for you.

denglish
4 / 5 (4) Mar 29, 2015
The ignorance and crackpottery is overwhelming.
rpaul_bauman
1 / 5 (2) Mar 29, 2015
Gentelmen; Math CAN NOT express physics correctly today. For a rather simple reason again; Math assumes every thing is continuous and in our universe everything is discrete. Even time is discrete, it goes tick, tick, tick. Nothing happens between ticks. IF you assume time is continuous, you need to really understand continuous.
andyarok
not rated yet Mar 29, 2015
@ Denglish
I cannot understand the fact that both you and topcat are actually talking one and the same and still argue against each other. I think its because you don't want to conceive what topcat is arguing here.

So answer me here,
Can we ever observe someone fall into a black hole? yes or no
Though I know he actually does fall into it, Can I observe it?

From my knowledge he will always be falling into it forever.
denglish
3 / 5 (2) Mar 29, 2015
@ Denglish
I cannot understand the fact that both you and topcat are actually talking one and the same and still argue against each other. I think its because you don't want to conceive what topcat is arguing here.

So answer me here,
Can we ever observe someone fall into a black hole? yes or no
Though I know he actually does fall into it, Can I observe it?

From my knowledge he will always be falling into it forever.

You're right Andy.

That doesn't mean that we can't observe phenomena associated with BH influence.

rpaul, you may be better off on a religious forum.
andyarok
not rated yet Mar 29, 2015
Ok, this confirms that you are is same page as TopCat to 95 %.

Yes, the problem with topcat is we are not talking about observing through light. We are talking about something else.

So topcat's line of argument is if we in our lifetime cannot see a person falling into a black hole, how can we see 2 blackholes merging into each other.

However, TopCat needs some enlightenment on the observed phenomenon.
@TopCat Refer the part
Won't it take forever for you to fall in? Won't it take forever for the black hole to even form?
http://math.ucr.e..._in.html

I suppose the English part of your illusion example is taken seriously by topcat.
Also calling someone or someone's line of thought nonsense would make them not to listen.
rufusgwarren
not rated yet Mar 30, 2015
Are you sure?
Anakin
1 / 5 (1) Mar 30, 2015
@TopCat22
I can clearly see how you think.
Add to that is that should be room for infinite information from our view, plastered on the EH.
It meen that everything ever falling into the black hole including all white hot glowing gas would be visual there to us.
So why can't we se those black holes?

Btw.
The ripples in ST we would see is those before the collision when we can see them orbit.
rpaul_bauman
1 / 5 (1) Mar 30, 2015
Denglish: "rpaulb, you may be better off in a religious forum". What makes you thing you understand religion any better than you do physics ? Guys : there are NO Black Holes !!! Before you go further with the Black Hole stuff, you have to be sure there are Black Holes. Most theories on gravity, more than half, DO NOT predict BHs. And nearly none of the latest ones do. And no one seems to understand that there are at least 100 different theories, all by PhDs. So if you have a favorite one, like GR, its chances of being correct is about 1 %.
TopCat22
1 / 5 (1) Mar 30, 2015
My more important point though is ... how do we get supermassive black holes and growth of black holes to happen if they cannot happen within our timeline?


This is how:

When a very massive star exhausts its nuclear fuel it explodes as a supernova. The outer parts of the star are expelled violently into space, while the core completely collapses under its own weight.

If the core remaining after the supernova is very massive (more than 2.5 times the mass of the Sun), no known repulsive force inside a star can push back hard enough to prevent gravity from completely collapsing the core into a black hole.

As the black hole gathers material that surrounds it (also known as accretion), that material adds to the mass of the black hole - growing it.


Do you have any understandings of your own on this subject... denglish?

As soon as the event horizon is created ... time stops there relative to us... Stops falling and no growing Black Holes are allowed.
casualjoe
not rated yet Mar 30, 2015
Gentelmen; Math CAN NOT express physics correctly today. For a rather simple reason again; Math assumes every thing is continuous and in our universe everything is discrete. Even time is discrete, it goes tick, tick, tick. Nothing happens between ticks. IF you assume time is continuous, you need to really understand continuous.


Allow me to suggest some 'causal set theory', for your perusal.

rpaul_bauman
not rated yet Mar 30, 2015
Hi casualjoe; are you talking about infinite sets or finite sets or both ? The point still is, Math can not express physics correctly today.. And a good exsample is General Relativity. GR has Black Holes, singularities and needs Dark Matter, and no explination for Dark Energy. GREAT MATH !! This is because math assumes all things are continuous. Particles are discrete. A continuous wave function is an approximation to a dicrete particle.
Accata
1 / 5 (1) Mar 30, 2015
Particles are discrete. A continuous wave function is an approximation to a discrete particle
Only for lightweight particles, like the photons (of long wavelength in addition). For any other particles the more realistic model is the pilot wave scenario: the wave function surrounds the particle like the bow (wake) wave around boat at the water surface. The difference from wake wave is, the pilot wave is not only affected with particle motion, but it also affects the future direction of this motion, therefore it serves as a probability wave. The particle itself remain tidy "discrete" object (internally it's also formed with standing waves, but these waves apply at much smaller distance).
denglish
3 / 5 (2) Mar 30, 2015
Do you have any understandings of your own on this subject... denglish?

As soon as the event horizon is created ... time stops there relative to us... Stops falling and no growing Black Holes are allowed.

Do time and events stop for the BH? :-)

You don't need to believe me. Ask the guys on the physics forums. :-)
TopCat22
not rated yet Mar 30, 2015
Yes time and events stop on the surface of the event horizon where time dilation equals infinity or a dead stop as far as you and I are concerned. To something falling in a different reality occurs. both are real. no illusions
denglish
3 / 5 (2) Mar 30, 2015
Yes time and events stop on the surface of the event horizon where time dilation equals infinity or a dead stop as far as you and I are concerned. To something falling in a different reality occurs. both are real. no illusions

No. time and events do not stop for the BH. Only distant observers experience the time dilation.

Actually, time dilation for a distant observer is an optical illusion. An in-faller fell in a long time ago, but a distant observer will only see the in-faller stop at the edge of the EH, and then slowly fade away as they red-shift into oblivion.

TopCat22
not rated yet Mar 30, 2015
Yes time and events stop for the distant observer on the event horizon.

The in-fallen never falls in for the distant observer ... really. no illusion... they don't fall all the way in as a fact.

Only to the in-fallen has the in-fallen fallen in. To everyone outside ... they did not fall in ... no illusions ... just two different realities .... just like the twins that are a hundred years apart in age when one orbits close to a black hole
Reg Mundy
3 / 5 (2) Mar 31, 2015
@furbrain
If you are reading this thread, you might think that N. Tesla and Cantdrive agree with me...
New research provides revelations


An international team of astronomers, including from the University of Cambridge, have found solutions to decades-old equations


"Today's scientists have substituted mathematics for experiments, and they wander off through equation after equation, and eventually build a structure which has no relation to reality." Nikola Tesla

BH's have no relation to reality!

Reg Mundy
3 / 5 (2) Mar 31, 2015
@rpaul_bauman

Gentelmen; Math CAN NOT express physics correctly today. For a rather simple reason again; Math assumes every thing is continuous and in our universe everything is discrete. Even time is discrete, it goes tick, tick, tick. Nothing happens between ticks. IF you assume time is continuous, you need to really understand continuous.

You been reading my book?
Benni
3 / 5 (4) Mar 31, 2015
Most theories on gravity, more than half, DO NOT predict BHs. And nearly none of the latest ones do. And no one seems to understand that there are at least 100 different theories, all by PhDs. So if you have a favorite one, like GR, its chances of being correct is about 1 %.


Do you think Einstein's GR predicts BHs?
Reg Mundy
5 / 5 (1) Mar 31, 2015
Gentlemen/Ladies, can I ask you just for a moment to imagine that gravity does not exist as a force, and that the effect we experience and call gravity is caused by the expansion of all matter. When sufficient matter is concentrated in one place, the expansion causes it to adopt a spherical shape. As the matter continues to expand, the outer surface of the sphere increases in velocity measured from the centre of mass. When this velocity reaches light speed, the matter can no longer expand as before, and, as our universe exists in "time" which itself is our experience of this expansion, the matter can no longer exist in our universe. In my theory, the matter breaks down into fundamental particles which can only be detected in our universe when they interact with each other (i.e. form matter).
OK, you can now dismiss this idea and go back to believing in gravity, gravity waves, gravitons, dark Matter, Dark Energy, etc. etc., and feel free to slag me off. But the idea is in your mind!
rpaul_bauman
not rated yet Mar 31, 2015
Thanks Reg Mundy. It is nice that someone will ask a question and stick on the subject. As best I remember, GR (its equations) ONLY includes space-time or what we call gravity, There are no other forces and the equations do lead to singularities as (d) distances between bodies reaches zero, since GR assumes distance is continious. Those singularities we call Blach Holes. Now I am not sure why you asked. I do not belittle Einstein any more than 100 people that wrote other theories. The guy was great for his time. The lastest theories MOG and LSG do not predict Black Holes. And of ALL 100 theories ONLY ONE predicts space is a particle, (spock, and there are 12), ie space is discrete. Seems that is more important to concider. I hope that will bring more questions. MOG ofcourse starts out with GR and adds a new force and changes the force to increase relatively to increasing distance so that Dark Matter is not needed. LSG does that without that change.
Benni
3 / 5 (4) Mar 31, 2015
the matter continues to expand, the outer surface of the sphere increases in velocity measured from the centre of mass. When this velocity reaches light speed
The velocity of "matter" can never reach "light speed", in accordance with the Mass Energy Equivalence Principle of Special Relativity. It would require an infinite amount of energy to make just one atom reach the speed of light. And where does energy come from? From the transformation of mass. I guess if you want to imagine there is an infinite quantity of "mass" in the universe available for transformation, then hypothetically you could accelerate some particle of mass to light speed, but good luck trying to locate an infinite supply of fuel.
Mike_Massen
2.3 / 5 (3) Mar 31, 2015
Benni showing ignorance of SR/GR claimed
The velocity of "matter" can never reach "light speed", in accordance with the Mass Energy Equivalence Principle of Special Relativity. It would require an infinite amount of energy to make just one atom reach the speed of light. And where does energy come from?
Incomplete, those educated would obviously understand caveat's re inertial vs non-inertial reference frames (IRF) wrt observer, can't U ?

Come across those of your misplaced zeal before & covered in last 12months on phys.org forum U attended.

You ignore Lorentz contraction re time in conjunction with the reference frame (RF). ie. It depends on which observer, doh !

ie. It is well accepted u can accelerate at Eg. 1G for 25yrs or so & from your RF u can reach center of our galaxy in your life BUT, the IRF of the origin a great deal of time passes ie Lorentz,

It's exactly Y reciprocal SR for GPS is Wrong & their V re SR its always as Non-IRF as proven, doh !
Benni
2 / 5 (4) Mar 31, 2015
I do not belittle Einstein any more than 100 people that wrote other theories. The guy was great for his time. The lastest theories MOG and LSG do not predict Black Holes.
Einstein's GR does not predict BHs. It's a total mystery to me why anyone believes such a thing.

Einstein Field Equations were used by Schwarzchild to set up his calculations escape velocity for stellar bodies given a specific mass & radius. It is the Shwarzchild equations that are used to hypothesize BHs by including the gravity ( calculated by Einstein Field Equations) of a body given its' radius & mass. When you know the gravity of a body you can then calculate necessary escape velocity all the way up to the speed of light of light for emission from the surface of a sphere.
rpaul_bauman
1 / 5 (1) Mar 31, 2015
Hi Benni, You are right and I agree with you. I tried to say that too, but my statements may not be clear. Are you now implying that GR is correct because of that reasoning ?
rpaul_bauman
1 / 5 (1) Mar 31, 2015
If Schwarzchild had used MOG or LSG we would not have Black Holes. As you said he used Einsteins field equations. So it seems fair to blame GR for Back Holes or any other theory that does the same. If you used those two theories we would not have Dark Matter either, so I think you can blame GR for that too. And no singularities either, all more blame on GR.
Reg Mundy
4 / 5 (4) Mar 31, 2015
@Benni
the matter continues to expand, the outer surface of the sphere increases in velocity measured from the centre of mass. When this velocity reaches light speed
The velocity of "matter" can never reach "light speed", in accordance with the Mass Energy Equivalence Principle of Special Relativity. It would require an infinite amount of energy to make just one atom reach the speed of light. And where does energy come from? From the transformation of mass.

The whole point of the comment was that matter cannot reach or exceed light speed, and in the context of the comment can no longer continue to expand. If our "time" is caused by this expansion of matter, then the object cannot continue to exist in our "time", i.e. our universe, and as our universe consists of matter, it must become non-matter.
Benni
3 / 5 (4) Mar 31, 2015
Hi Benni, Are you now implying that GR is correct because of that reasoning ?
Yes

As you said he used Einsteins field equations. So it seems fair to blame GR for Back Holes
Well not really, because it's not fair to tag Einstein with a label for something he never proposed within the context of his thesis.

If you used those two theories we would not have Dark Matter either
....or with GR & SR for that matter. Every hypothesis proposed for DM violate massive amounts of either GR or SR.

And no singularities either, all more blame on GR.
Once again, it is extrapolations made from the Schwarzchild Radius of calculations that give rise to all this BH & Singularity hypothesis. The Singularity issues are an even bigger can of worms to open up apart from BHs because of an "infinity" issue & the portent that opens up for negative gravity arguments.
rpaul_bauman
1 / 5 (1) Apr 01, 2015
Read Moffat's MOG. MOG starts with General Relativity and corrects 5 major problems with GR. MOG is still a piece of junk however. That's how stupid General Relativity is, that after correcting its problems you still have a piece of junk. . LSG is different, don't want you to get too smart by reading it..
Mike_Massen
3 / 5 (2) Apr 02, 2015
rpaul_bauman claimed
That's how stupid General Relativity is, that after correcting its problems you still have a piece of junk. . LSG is different, don't want you to get too smart by reading it..
Global Positioning Satellites (GPS) rely on GR/SR corrections for their continued operation and several times each day the clocks are corrected, the maths stacks up with predictions, ie There is Evidence for SR/GR and it is arithmetic (not geometric) in terms of corrections.

How would GPS function rpaul_bauman, without those corrections please & why does it fit ?

Not acquainted with LSG - does any maths in it allow GPS to work as well as it does with GR/SR corrections ?
rpaul_bauman
not rated yet Apr 02, 2015
You DO NOT determine if a theory is correct by what it does right. You determine if it is incorrect by what it does wrong. Besides GPS uses Special Relativity not General Relativity. As I said several times already GR has 5 major problems, and most major, Dark Matter. Read John Moffat's book "Reinventing Gravity". He lists all 5 and corrects them in his theory on gravity, MOG. You are right, don't take my word , read what he said in his book on MOG. There are MANY people that think GR is SUPER GREAT, but once again if it were correct there would not be 99 newer theories on gravity. ALL correcting things WRONG with General Relativity. People that love GR don't list things wrong, they only list things right. Try them both once Visit Science World on internet, there are at least 8 Ph.Ds that agree with the theory that General Relativity is the only correct theory. And it leads to infinite universes for infinity, start your RIGHT list with that one.
rpaul_bauman
not rated yet Apr 02, 2015
AS for LSG, does it include Special Relativity, yes. But it does change it some. As for gravity, LSG allows gravitons to travel faster than a real photon, and gives the reason for both limits. Have you ever read why a real photon has a limit of C ? Should you think that is impossible , study Opera 1, were neutrinos were found to go faster than light and then ALL decided a cable was lose. But what the results showed was that the pulse of neutrinos CHANGED shape. ALL, ALL the last neutrinos caught up to the first ones. That happens with super novas too. So they reran the experiment with Opera 2 and used a very short pulse, lots of luck !!! And LSG explains that too.
Mike_Massen
3 / 5 (2) Apr 02, 2015
rpaul_bauman stated
You DO NOT determine if a theory is correct by what it does right
To a degree, sure.

rpaul_bauman claimed
..GPS uses Special Relativity not General Relativity
NO.
Completely WRONG, please get education
https://en.wikipe...g_System

rpaul_bauman claimed
As I said several times already GR has 5 major problems, and most major, Dark Matter
No. GR effects upon time r not proven re ANY imagined DM distributions.

rpaul_bauman stated
.. GR is SUPER GREAT, but once again if it were correct there would not be 99 newer theories on gravity
There are NOT 99. Variants may attempt to weave DM in but, it doesnt make it experimentally correct (yet).

rpaul_bauman claimed
ALL correcting things WRONG with General Relativity
Other than odd DM claims what substantively is there supposedly definitively wrong on GR ?

Check this in detail & do the math please
https://en.wikipe...periment
Mike_Massen
3 / 5 (2) Apr 02, 2015
cont
rpaul_bauman claimed
People that love GR don't list things wrong, they only list things right
NOT above love, & NOT about ANY emotional attachment (eg religion), its about "balance of probabilities". GR fares rverywell with host of experimental support. Researchers would be in line for a Nobel if they found anything definitely flawed in just ONE experiment that could be replicated, do u not see that ?

Conjecture about the nature of DM or equivalent effect is NOT an experiment & it is NOT definitive, until that time, if it arises, GR works fine - so other than perceptions re imagined DM effects, just what is there re any repeatable experiment which invalidates GR - even a little please ?

rpaul_bauman claimed
.. And it leads to infinite universes for infinity..
No. GR doesn't automatically lead there, if u think it does then show the math or link to paper on THAT !

Indicate flaw please ?
https://en.wikipe...lativity
Mike_Massen
3 / 5 (2) Apr 02, 2015
rpaul_bauman claimed
.. LSG, does it include Special Relativity, yes. But it does change it some
U failed to answer my initial question re GPS, so r u a follower or a thinker that can do math ?

How precisely does LSG offer GPS required corrections so it works SAME as GR predicts ?

rpaul_bauman claimed
..LSG allows gravitons to travel faster than a real photon..
Evidence pls ?

rpaul_bauman claimed
... study Opera 1, were neutrinos were found to go faster than light and then ALL decided a cable was lose
IIRC; issue re start vs middle of packet etc Nothing definitive & NOT repeatable ie A fail.

rpaul_bauman claimed
.. results showed was that the pulse of neutrinos CHANGED shape
Evidence pls - which N detector ?

rpaul_bauman claimed
.. happens with super novas too. .. And LSG explains that too
Photons have particular issue re refraction/delays ie Photons from Sol's core take ~800K years but, neutrinos pass through 8mins, ie not > c !

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