Solving Einstein’s theory

Nov 03, 2011
Solving Einstein’s theory

A team of University researchers will get their hands on some of Europe’s fastest supercomputers in a bid to crack Einstein’s theory of relativity and help describe what happens when two black holes collide.

Experts in gravitational waves from the School of Physics and Astronomy have secured almost 16.7 million hours worth of supercomputer time to simulate and map the most violent events in the universe since the big bang – namely, collisions of black holes.

The team will use more than 1,900 computer processors over the next year to try and solve the equations of Einstein’s general theory of relativity.

The ultimate goal of the simulations is the direct observation of black-hole collisions through the gravitational waves they emit.

"Gravitational waves are ripples in space and time – predicted by Einstein almost 100 years ago," according to Mark Hannam, School of Physics and Astronomy, who will lead the Cardiff research team.

"However, despite Einstein’s predictions – they have not yet been directly detected. Gravitational waves are generated by accelerating masses, such as orbiting black holes, similar to the way accelerating electrical charges emit electromagnetic waves, like light, infra-red and radio waves - with the important difference that gravitational waves are far weaker.

"For this reason it is electromagnetic waves that have told us everything we have learnt about the cosmos since ancient times. If we could also detect gravitational waves, that would push open a new window on the universe, and tell us about its `dark side'," he added.

Over the past decade a network of gravitational wave detectors has been built, including the US Laser Interferometer Gravitational-Wave Observatory (LIGO) and the European GEO600 and Virgo detectors, with the ambitious goal of not only making the first direct detection of the gravitational waves, but also to observe the entire Universe through gravitational radiation.

Cardiff's researchers work on theoretical modelling of black-hole-binary collisions using state-of-the-art numerical techniques and high performance computer clusters, strong field tests of gravity with gravitational-wave observations and the development of algorithms and software to search for .

Researchers at Cardiff play leading roles within the LIGO Scientific Collaboration, in particular in gravitational-wave searches for compact binary coalescences, supernovae, gamma-ray bursts, and other transient sources.

Coalescing black holes are prime candidates for the first observations. The results of this project will help to identify the sources of these signals, and contribute to answering important open questions in astrophysics and fundamental physics, such as whether the objects created in these cosmic collisions are really black holes, or even more exotic objects like naked singularities.

In the process the team hope to be able to test if Einstein's theory of gravity is correct, or whether, just as Newton's gravity gave way to Einstein's, perhaps Einstein's relativity gives way to even deeper insights into the nature of space and time.

The research team comprises more than 20 physicists working at Cardiff, the Universities of Jena, Vienna, and the Balearic Islands, the Albert Einstein Institute in Potsdam, and the California Institute of Technology. Solving Einstein's equations on supercomputers to accurately describe became possible only after a series of breakthroughs in 2005, and the mostly young researchers are excited to be part of a scientific revolution.

"The detectors are pushing against the limits of current technology, and now we will help them with simulations that are at the cutting edge of computing power. Access to such vast computing resources is a fantastic boost for scientific research in Wales," Dr. Hannam added.

While supercomputing resources in used to be relatively scarce, the PRACE Research Infrastructure now provides access to world-class supercomputers for European research projects, which undergo a competitive peer review process.

The PRACE infrastructure currently consists of three world-class supercomputers, which can each perform about 1 Petaflop which is a thousand billion arithmetic operations per second. The first machine in the network, the German Jugene, started operation in 2010, and it was joined in early 2011 by the French machine Curie, and the German system Hermit is about to officially start operation on November 1.

Future computers in the PRACE network are planned in Germany, Italy, and Spain.

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antialias_physorg
4.2 / 5 (10) Nov 03, 2011
that would push open a new window on the universe, and tell us about its `dark side'

Something, something, something, DARK SIDE.
In the process the team hope to be able to test if Einstein's theory of gravity is correct,

Something, something, something, COMPLETE.

Sorry...just couldn't resist.
typicalguy
1.8 / 5 (5) Nov 03, 2011
The universe is huge. Anything that can happen either has or will happen at some point in the future. That said, what happens when a black. Hole and a black hole made of antimatter collide?
Royale
3 / 5 (1) Nov 03, 2011
I enjoyed the Family Guy reference personally. Thanks anti.
And you're totally right, they should have said complete instead of correct. Because we've already shown that many aspects are correct already.
sandler
1 / 5 (3) Nov 03, 2011
If the stars can be compared to trees with gravitational roots spread out inside a galaxy (forest), then a black hole could be compared to a raging fire. According to wiki there's one raging fire of 4 million solar masses currently occurring inside our Milky Way galaxy. What happens when two separate fires meet? (src:Sci-Fi)
Callippo
1.1 / 5 (7) Nov 03, 2011
As Eddington pointed out already before many years, gravitational waves do not have a unique speed of propagation. The speed of the alleged waves is coordinate dependent. A different set of coordinates yields a different speed of propagation and such waves would propagate like well known CMBR noise.

In another words, the physicists are looking for phenomena, which is known for years just because their formal models lead to the more deterministic results, then they would lead without their simplifications. The same result can be imagined easily with water surface analogy of dense aether theory, where transverse waves are serving like analogy of waves of light and the gravitational waves are behaving like longitudinal sound waves, which are spreading through underwater. Because sound waves are spreading a way faster, then the surface waves, they would manifest like indeterministic noise at the water surface.
Callippo
1.4 / 5 (8) Nov 03, 2011
Relativists use a simplified form of Einstein field equations to calculate various properties of his gravitational field, including Einstein gravitational waves, which are based on the Einstein's pseudo-tensor. This simplified form is called the linearised field equations. They do this because Einstein's field equations are highly non-linear (implicit actually) and impossible to solve analytically. So they use the linearized form, simply assuming that they can do so.

However Hermann Weyl proved in 1944 already, that linearization of the field equations implies the existence of a Einstein's pseudo-tensor that, except for the trivial case of being precisely zero, does not otherwise exist. On the existence of this pseudotensor the existence of gravitational waves in GR is based.

http://www.jstor..../2371768

The jobs keeping mechanism prohibits both theorists, both experimentalist to accept well known and simple connections, because gravitational waves are salary generator.
nkalanaga
2 / 5 (4) Nov 03, 2011
A black hole made of antimatter still has positive mass. Since mass and energy are equivalent, and the energy is trapped in the merged black hole, there wouldn't be any difference between a M-AM merger and a M-M or AM-AM merger. In all three cases you simply get a bigger black hole.
Callippo
1.2 / 5 (6) Nov 03, 2011
there wouldn't be any difference between a M-AM merger and a M-M or AM-AM merger
IMO it's impossible to observe the AM black holes inside the event horizon of our Universe because their particles are very sparse and they're exhibiting a repulsive gravity mutually. But if it could exist, they would merge with M and AM black holes quite differently. AM black holes would be very radiative like the quasars.
210
1 / 5 (1) Nov 03, 2011
But if it could exist, they would merge with M and AM black holes quite differently. AM black holes would be very radiative like the quasars.

You are on to something...got any more where this came from? Radiative? Why? Because they are.....

word-
Deesky
5 / 5 (3) Nov 03, 2011
Solving Einstein's equations on supercomputers to accurately describe black holes became possible only after a series of breakthroughs in 2005, and the mostly young researchers are excited to be part of a scientific revolution.

Sheesh! You'd think they'd elucidate in what that series of breakthroughs was, instead if leaving us hanging...
Seeker2
not rated yet Nov 04, 2011
Article:
...Petaflop which is a thousand billion arithmetic operations per second.

Maybe a thousand trillion?
Seeker2
not rated yet Nov 04, 2011
Callippo:
...gravitational waves are behaving like longitudinal sound waves

That's what I was thinking. Gravitational waves are actually moving the medium whereas photons propagate through the medium.

...Einstein's field equations are highly non-linear (implicit actually) and impossible to solve analytically. So they use the linearized form, simply assuming that they can do so.

It seems to work for photons propagating in a gravitational field. I assume this requires the field equations.
Seeker2
1 / 5 (2) Nov 04, 2011
nkalanaga:
...A black hole made of antimatter...

I don't worry about that since IMO antimatter experiences antigravity. As Callippo says,

Callippo:
...they're exhibiting a repulsive gravity mutually

ubavontuba
2.5 / 5 (8) Nov 04, 2011
Isn't it obvious? Nothing happens.

"...the collapsed stars (black holes) were called "frozen stars," because an outside observer would see the surface of the star frozen in time at the instant where its collapse takes it inside the Schwarzschild radius."

http://en.wikiped...lativity

...or maybe not.

Here's a related puzzler:

If a black hole distorts spacetime to such an extent that time stops at the event horizon relative to all outside observers, can black holes exihbit linear momentum relative to the rest of the matter in the universe?

antialias_physorg
4.4 / 5 (7) Nov 04, 2011
...Petaflop which is a thousand billion arithmetic operations per second.

Probably a translation error, since most roman languages go

million (10 to the 6th)
milliarde (10 to the 9th)
billion (10 to 12th)
billarde (10 to the 15th)
trillion (10 to the 18th)
trilliarde (10 to the 21st)
etc. ...

Only in english do you jump from million (10 to the 6th) to billion (10 to the 9th) to trillion (10 to the 12th).

Since this article probably originated in german or french I'd guess it was talking about "Billionen von Operationen" (which translates to 'trillions of operations' not 'billions of operations' in english)
rawa1
2 / 5 (4) Nov 04, 2011
Gravitational waves are actually moving the medium whereas photons propagate through the medium.
Both waves are propagating through vacuum, but the aether model of vacuum always requires the presence of two kinds of waves: transverse and longitudinal ones. These two kinds of waves exist in every inertial environment and it belong into the most basic predictions of this model.

Mainstream physics is still in very rudimentary level of understanding of material nature of vacuum, despite the pile of math. Actually its quite surprising what the theorists manage to derive about it, despite they've no idea, what they're dealing with.

In many cases such formal approach can lead to satisfactory results, but the concept of gravitational waves really requires to understand the duality of transverse and longitudinal waves at their intuitive level. The model of gravitational waves of relativity is wrong at the elementary logic level.
rawa1
1.8 / 5 (5) Nov 04, 2011
The basic problem in derivation of gravitational waves in general relativity is in their assumption, they're moving with luminal speed. Such assumption is completely ad-hoced and it doesn't follow from anything else. The physicists had chosen this speed for the sake of consistency with special relativity. To determine the speed of gravitational waves we need to define the reference frame for its motion. In general relativity the reference frame doesn't exist, until space-time is not curved at least a bit. Which brings the apparent problem immediately: the gravitational wave, which is formed with curvature of space-time only serves both as a object defining its speed, both as the object, defining the reference frame of this speed. It's actually mixing of intrinsic and extrinsic perspectives, which is surprisingly frequent in contemporary mainstream physics and it leads to wrong conclusions, regarding the entropy derivation of black holes, gravity of antimatter and in many other cases.
Ramael
2.3 / 5 (3) Nov 04, 2011
[delete] :P
antialias_physorg
4.3 / 5 (6) Nov 04, 2011
The universe is huge. Anything that can happen either has or will happen at some point in the future.

Nope. Most anything is far more unlikely than the universe can account for. The universe is huge, but not infinite (neither in space nor time)

For example something as simple as flipping an ideal coin and having it come up 100 times 'heads' in a row is so unlikely that if you were to have done it since the beginning of time, trying for 100 tosses per second, then you would have to have done this in 100 million billion places in parallel to expect one occurence of such a series by now.

If you go to 1000 'heads' in a row then you could toss coins once per atom in every Planck time (shortest time for anything to happen in) for the entire duration of the universe and still be far, far, FAR from likely that you'd ever see such an event crop up once.
roboferret
5 / 5 (3) Nov 04, 2011
nkalanaga:
...A black hole made of antimatter...

I don't worry about that since IMO antimatter experiences antigravity. As Callippo says,

Callippo:
...they're exhibiting a repulsive gravity mutually



There is no evidence yet as to whether antimatter has anti-gravity properties, but most theories predict it will interact attractively. Relativity seems to support this, matter/antimatter annihilations produce positive energy, indicating positive mass (E=MC^2), and thus positive curvature of space-time and normal gravity. Experiments will prove one way or the other in next few years.
I'm not sure how useful it is to talk about black hole singularities in terms of matter/antimatter anyway.
If antimatter was repelled by normal matter, antiparticles generated in the accretion disk would be rapidly accelerated away from a black hole, and we could detect large amounts of high energy antiparticles from the the direction of black holes.
antialias_physorg
5 / 5 (7) Nov 04, 2011
Add to that that matter is probably not going to stay that way once it enters a black hole.

It will likely be ripped into a quark gluon plasma long before it reaches the 'center'. So there would be no meeting of 'a high mass of matter and antimatter' anyhow if a black hole originating from a matter star and one originating from an anti-matter star were ever to meet.

That said: black holes being what they are - once they meet then you would never see any of the effects anyhow. What happens in Vegas...erm...in a black hole...stays in a black hole.
Seeker2
1 / 5 (2) Nov 04, 2011
ubavontuba:
...can black holes exihbit linear momentum relative to the rest of the matter in the universe?

Like with gravity?

Seeker2
1 / 5 (2) Nov 04, 2011
roboferret:
...There is no evidence yet as to whether antimatter has anti-gravity properties

Well maybe except for Hawing radiation. The matter particle and its negative energy falls into the black hole and the anti-matter particle with its positive energy escapes. The gravitational field is pretty strong at the event horizon, too. So black holes radiate energy and anti-particles, or so it would seem.
Seeker2
1 / 5 (3) Nov 04, 2011
antialias_physorg:
...anti-matter star

Please. Stars aren't formed from repulsive anti-matter particles. Their positive energy will propel them to regions of spacetime where there is minimal gravity.
Seeker2
1 / 5 (2) Nov 04, 2011
roboferret:
...If antimatter was repelled by normal matter, antiparticles generated in the accretion disk would be rapidly accelerated away

True, I guess.

...we could detect large amounts of high energy antiparticles from the direction of black holes.

Hawking (blackbody) radiation hasn't been directly detected so detecting high energy particles would be unlikely.
Seeker2
1 / 5 (2) Nov 04, 2011
rawa1:

...Gravitational waves are actually moving the medium whereas photons propagate through the medium. -seeker2

...Both waves are propagating through vacuum

Photons propagate through spacetime. Gravitational waves actually move spacetime through the vacuum. Photons do not propagate through the vacuum because the vacuum is a medium for spacetime only.

For example during the inflationary BB spacetime was blown away through the vacuum faster than the speed of light. So many parts of the U are hidden from us because there are intermediate voids in the U which do not transmit light.
Seeker2
1 / 5 (2) Nov 04, 2011
rawa1:
...gravitational waves in general relativity is in their assumption, they're moving with luminal speed. Such assumption is completely ad-hoced and it doesn't follow from anything else.

If this is so how do they correctly predict the effect of gravity on photons?

...which is surprisingly frequent in contemporary mainstream physics and it leads to wrong conclusions, regarding the entropy derivation of black holes, gravity of antimatter and in many other cases.

I would think Hawking is mainstream physics and if he thinks antimatter experiences gravity he contradicts his ideas on Hawking radiation.

...Mainstream physics is still in very rudimentary level of understanding of material nature of vacuum

That could be because there is no material nature of the vacuum.
Seeker2
1 / 5 (2) Nov 04, 2011
roboferret:
... matter/antimatter annihilations produce positive energy, indicating positive mass (E=MC^2), and thus positive curvature of space-time and normal gravity

Note: The curvature of spacetime from positive mass represents negative energy in Hawking's view. That way the positive energy of matter balances out the negative energy of the gravitational field and the total energy of these two sources is 0. I suppose the opposite would hold for antimatter and antigravity; the total energy from these two sources would also be 0. This doesn't mean the total energy of the U is 0 because you still have dark energy which drives expansion and dark matter which results from turbulence in the expansion. Did I forget anything? IMO the total energy of the U began with complete dark energy. The matter and antimatter contributions are cancelled by gravity and antigravity. So the total energy of the U is the energy of DE at the big bang. If not, what happened to it?
Seeker2
1 / 5 (2) Nov 04, 2011
Note: The curvature of spacetime from positive mass represents negative energy in Hawking's view. That way the positive energy of matter balances out the negative energy of the gravitational field and the total energy of these two sources is 0. I suppose the opposite would hold for antimatter and antigravity; the total energy from these two sources would also be 0. This doesn't mean the total energy of the U is 0 because you still have dark energy which drives expansion and dark matter which results from turbulence in the expansion. Did I forget anything? IMO the total energy of the U began with complete dark energy. The matter and antimatter contributions are cancelled by gravity and antigravity. So the total energy of the U is the energy of DE at the big bang. If not, what happened to it?
Seeker2
1 / 5 (2) Nov 04, 2011
cont...
Actually, if you think about it, the material U is just a minor theme played out on the instrument of spacetime expansion. Material seems to come from the cooling of DE as it spreads out in spacetime. If you think the U is cyclical, note that when the DE runs out and (accelerated) expansion stops, DE is totally converted to expanded (stretched) spacetime. If spacetime tries to contract back to its original volume, the temperature of spacetime increases as it contracts and returns its energy to the DE and no condensation into forms of matter/antimatter is possible until the next cooling cycle (BB). Sort of like a heat pump maybe.

People like to conjecture about what would happen with time running backwards. There being no matter, you don't have to worry about broken dishes majically coming together and setting back on the table.
ubavontuba
1.8 / 5 (5) Nov 05, 2011
Like with gravity?
No, not like with gravity. Like with time. Try reading my post again.

antialias_physorg
5 / 5 (2) Nov 05, 2011
Please. Stars aren't formed from repulsive anti-matter particles.

I'm not aware that there is any study that says antimatter is mutually repulsive. Link?
roboferret
5 / 5 (1) Nov 05, 2011

Note: The curvature of spacetime from positive mass represents negative energy in Hawking's view. That way the positive energy of matter balances out the negative energy of the gravitational field and the total energy of these two sources is 0. I suppose the opposite would hold for antimatter and antigravity; the total energy from these two sources would also be 0.


I addressed this. If that were the case, matter/antimatter annihilations would produce zero net energy, but in experiments they clearly produce the positive sum energy equivalent of their mass. Would you care to cite something that states otherwise?
Seeker2
1 / 5 (2) Nov 05, 2011
roboferret:
...If that were the case, matter/antimatter annihilations would produce zero net energy

I'm talking about gravity balancing out matter and anti-gravity balancing out anti-matter. It certainly is true that annihilation returns the energy required to form pair production to spacetime. It's returned as radiation. Think of matter as positive curvature in spacetime resulting in negative curvature of the surrounding spacetime (gravity). So the gravitational field is a region of negative curvature in spacetime.
Seeker2
1 / 5 (2) Nov 05, 2011
cont...
This is the way physicists began to talk about gravity when they observed light following a curved path in spacetime. It seems more intuitive to think at the quantum level with spacetime elements compressed or expanded (distortion, or bending, in any case) instead of curvature. Compression corresponds to what they talk about as negative curvature. (Uncle Al isn't here to defend himself). So if you compress local elements of spacetime into a matter particle adjacent elements are stretched into an antimatter particle. The internal energy of matter is the energy required for this separation of spacetime into locally compressed (dense) areas (matter) and expanded areas (anti-matter). If this distortion is great enough and holds for a sufficiently long time (as dictated by the uncertainty principle) surrounding elements of spacetime may intervene and expel the antimatter particle to less dense regions of spacetime like releasing a beachball under water.
Seeker2
1 / 5 (2) Nov 05, 2011
cont...
You could say the strong force is what separates compressed and expanded regions, but what actually separates the regions is the uncertainty principle. The strong forces just step in and latch onto this distortion if it is great enough, shaped right, and lasts long enough. (I leave shaping to the string theorists). It cannot hold on forever, however. Eventually the uncertainty principle will break it and the internal energy of the particle is released back into spacetime in the form of radiation.

Note the electron (perhaps all leptons) do not radiate because they're not held together by the strong force. More likely it is a rearrangement of spacetime elements of electric flux, as modelled for example in loop quantum gravity. So anyway now you know where I'm coming from.
Seeker2
1 / 5 (2) Nov 05, 2011
...Note the electron (perhaps all leptons) do not radiate

Also I suppose positrons and all anti-leptons. Imagine the end times - a U filled with leptons, radiation, and anti-leptons. What an explosive combination that would be. Speculation is fun, publication is a pain. <:-)
Cave_Man
1 / 5 (1) Nov 05, 2011
While I hate to agree with the trolls I do think a reexamination of the fundamental nature of space and time will need to be undertaken.

A question that someone posted in another article: "If the sun radiates a photon from its eastern and western hemisphere at the same time and they are traveling in opposite directions how do you determine their speed using only the two photons as reference?"

Meaning that unless you include the initial emission point in the field equation you cannot complete the equation according to special relativity (i have no idea what im talking about)

But wouldn't this also have consequences on a universal scale? Aren't there laws of physics or at least theories that depend on the observed shape of the universe? But if we can see anywhere close to the big bang that would mean we are traveling away from the big band at the speed of light but then how could we observe it at all because the light would be stationary compared with our outward movement.
Cave_Man
1 / 5 (2) Nov 05, 2011
And if we can really see the big bang (or anywhere close to it) then that leads to other questions like how would it have looked in the past or will look in the future, it's like observing a photon then a million years from now observing the same photon because its right where you left it. assuming simplified spatial dynamics.

So am I correct in assuming that we still know 'relatively' nothing about the nature of the universe? It seems we have only cobbled together a simplistic rulebook based on the things that are observable right now.

What will the speed of light be in another 10-15 billion years? How can one even measure time accurately relative to things like the big bang and black holes? Or time on jupiter?

It seems like life in general is about estimating and never truly measuring something. Knowledge is a fallacy because it can be lost when you die.

Physics, philosophy and biology need to make a huge leap forward and combine into one field, called BioPhysicaloSophism.
Seeker2
1 / 5 (2) Nov 05, 2011
antialias_physorg:
...I'm not aware that there is any study that says antimatter is mutually repulsive.

Technically true. Antimatter (expanded elements of spacetime) is not mutually repulsive. However when mixed with undistorted ("empty") spacetime, "empty" spacetime mediates the repulsive force. That is, it intervenes between antimatter particles and these particles may be repulsed by the same "empty" elements of spacetime. So they're effectively repulsed from each other as long as they're mixed in with undistorted spacetime.

An anology would be high pressure areas. These areas repulse each other when mediated by lower pressure areas. Similarly low pressure areas attract each other (as in gravity) as they are pressed together by higher pressure areas.

...Link?
Wish I could find a good one. I did find one that talks about "Gravity, a polarized subatomic particle". My thinking is more intuitive.
Cynical1
1 / 5 (1) Nov 05, 2011
Okay, this might sound simple and sort of stupid to all of you who are better educated than myself - but, I'm goin with it, anyway...
Matter density equates to gravitational "density" (ie - strength of field). Get enough "bodies" together and you have an increased field.
Now we'll get to speed. Wouldn't the speed of propagation increase, the higher the "bodies"(smaller gravitational fields)count you have? At least between the closer bodies.
Therefore a "small gravitional field" that happens to be farther away will see it after a longer period of time? OR at the same time but with less interactive intensity? Is there observational proof of the currently accepted answer?
I guess in the short version, wouldn't proximity equal increased speed between the fields, but the density (number of gravitational interactions)actually slowing the speed at which it gets to the less dense area of gravitational fields?
Or is the speed the same, but the route is different?
Seeker2
1 / 5 (1) Nov 05, 2011
Cynical1:
...Now we'll get to speed. Wouldn't the speed of propagation increase, the higher the "bodies"(smaller gravitational fields)count you have?

So more bodies mean smaller gravitational fields?

...Or is the speed the same, but the route is different?

Maybe like a Feynman path integral where you have to integrate through all possible paths (or routes).
antialias_physorg
5 / 5 (3) Nov 05, 2011
Technically true. Antimatter (expanded elements of spacetime) is not mutually repulsive. However when mixed with undistorted ("empty") spacetime, "empty" spacetime mediates the repulsive force.

And this has been shown by what experimen? Or by what calculation? I can't find anything that would inidcate this is true (or even makes sense)

(i have no idea what im talking about)

Bit obvious, that.
So am I correct in assuming that we still know 'relatively' nothing about the nature of the universe?

What do you mean by 'relatively nothing'? Relative to what? Relative to 100 years ago we know a whole lot. Realtive to the thousands of years of religious gabbeling on the subject we know an enormous amount.

How can one even measure time accurately ...

Time is relative to your frame of reference. There is no 'accurate' time. Simultaneity went out the window when we started doing Relativity.
http://en.wikiped...ltaneity
hard2grep
1 / 5 (1) Nov 05, 2011
What if gravity was like the Coriolis force in which it is only apparent yet has a real effect on relative positions? just joking, imagine what a folding project could do with this.lol..
Cynical1
1 / 5 (1) Nov 05, 2011
"So more bodies mean smaller gravitational fields?"

No. Larger aggregate fields. I guess I meant that that speed at which they communicate gravitationally. The closer the field the faster the speed. And the faster the speed, the higher the density? This may not be exactly what I mean, so I guess it's still percolating in my head what I actually want to convey.
However, I do see it in a similar way to connectivity theory.
Seeker2
1 / 5 (2) Nov 06, 2011
antialias_physorg:
...Technically true. Antimatter (expanded elements of spacetime) is not mutually repulsive. However when mixed with undistorted ("empty") spacetime, "empty" spacetime mediates the repulsive force.-Seeker2

...And this has been shown by what experimen? Or by what calculation? I can't find anything that would inidcate this is true (or even makes sense)

Please be kind. I'm really a very sensitive and nice guy, I think. Anyway someone said they know I can think.

People seem to be a bit hesitant about experiments with black holes and Hawking radiation has yet to be directly tested. In the meantime I guess we'll have to settle for simple minded experiments. Like balloons. Deflate them and what happens? They seem to be affected by gravity. Inflate them and they seem to experience anti-gravity. Pop them both at the same time near each other with intervening normal atmospheric pressure and they would likely move apart (anti-gravity).
Seeker2
1 / 5 (2) Nov 06, 2011
cont...
...Hawking radiation has yet to be directly tested.

Maybe I meant detected.

Anyway, pop both balloons at the same time near each other with intervening normal atmospheric pressure and they would likely move apart (anti-gravity). Pop them in an atmosphere of high pressure like that in each balloon and I don't think much would happen. Put them in a tank and inflate the tank to a high pressure. My guess is they would be squeezed together (more gravity) so as to take up less volume than if they were separated.

Einstein was great on thought experiments. He didn't do bad for a low budget scientist. Hope this experiment makes a little sense. That's the whole idea of proposing this model. At least to me, it makes sense.
Cynical1
1 / 5 (1) Nov 06, 2011
seeker2 - the 2 balloons experiment wouldn't work.
If both were inflated (higher pressure inside of them versus lower pressure inside). They would fly apart only if the parts poked were on the opposing inside (closest to eachother)points. Poke them on the outside and they would push together, allowing for minor air turbulence.
In a place where pressure was greater outside of them than inside, they would not be inflated. If you somehow COULD inflate them, they would just implode.

That said - the simpleness of your analogy and obvious solution to it, puzzles me. I have read many comments by you, of much more complex nature, that you readily & competently presented. What's going on?
(Admittedly, I am easily confused on occasion)
Cynical1
1 / 5 (1) Nov 06, 2011
"(higher pressure inside of them versus lower pressure inside)"
I meant - Higher pressure inside vs lower pressure OUTside

And - maybe I missed something about what you were trying to convey....
Seeker2
1 / 5 (1) Nov 06, 2011
Cynical1:
...They would fly apart only if the parts poked were on the opposing inside (closest to eachother)points.

Try this: Take 2 pairs of air hoses. Clamp each pair together so they point in opposite directions. Now bring them together one end of each pointing opposite the other. Now turn on the air. What happens? Could be a good experiment for a low budget science department if you could keep the guys from playing games with the hoses.
antialias_physorg
5 / 5 (2) Nov 06, 2011
Deflate them and what happens? They seem to be affected by gravity. Inflate them and they seem to experience anti-gravity.


THAT is your experiment (or your 'analogy')? You have GOT to be joking.

Comparing such...erm...'brainfarts' with the mathematically rigorous work on Hawking radiation is the height of hubris.

Einstein was great on thought experiments. He didn't do bad for a low budget scientist.

Einstein was great on maths and physics.

Putting out some loony theory 'because it sounds good' is not how great scientists work. And you should really not be comparing yourself to sciengtists (great or otherwise) until you even start to do some work before putting out a theory.
Seeker2
1 / 5 (3) Nov 06, 2011
antialias_physorg:
...Putting out some loony theory 'because it sounds good' is not how great scientists work.

True. The rest of us have to stick to theories that work.
Seeker2
1 / 5 (2) Nov 07, 2011
Seeker2:
...Try this: Take 2 pairs of air hoses...

Much better idea: Try to simulate the laws of gravity using two vacuum cleaner hoses. If you really want to get scientific try measuring the force necessary to separate the opening ends of the hoses as a function of the of separation distance. See if you get something like the inverse square law. In the meantime keep those cards and letters of appreciation coming in.

Note: If you seem to be getting the wrong results you can always call in the litigators.
k4ntico
1 / 5 (2) Nov 07, 2011
10^7 hours of supercomputer time ! What's that in Joules, or equivalent emitted CO_2 ?
rawa1
1 / 5 (3) Nov 07, 2011
10^7 hours of supercomputer time ! What's that in Joules, or equivalent emitted CO_2
Well, it's quite relevant question, IMO. The mainstream physicists know very well about my arguments, which were presented before fifty years in mainstream peer-reviewed press, after all. If they're still refusing to consider the model, which leads into testable predictions and they continue in wasting of money in unphysical simulations and building of gravitational wave detectors - then we should simply ask, who and how is responsible for this situation and how to avoid such a waste.

IMO it's solely objective and relevant question, free of political connotations.
lerssi
1 / 5 (1) Nov 07, 2011
Isn't it obvious? Nothing happens.

frozen in time at the instant where its collapse takes it inside the Schwarzschild radius."

...or maybe not.

Here's a related puzzler:

If a black hole distorts spacetime to such an extent that time stops at the event horizon relative to all outside observers, can black holes exihbit linear momentum relative to the rest of the matter in the universe?


Yeah! As far as the rest of the universe is concerned, nothing ever, nevermore happens inside the timeless event horizons... Kinda protecting soap bubble keeping abnormal physics of singularity from crapping on my front lawn.
So - makes me a bit sceptical about Hawking radiation, as virtual particle pairs can never form underneath eh.
And not just momentum and kinetic mass... Gravitational mass could never affect outside universe, so either gravity is a pushing force (sort of like, say pressure differential) or eh cannot be impenetrable which would make special relativity completely bogus.
Feldagast
1 / 5 (1) Nov 07, 2011
Wonder why they cant come up with a way for more things like this to use distributive computing.
Seeker2
1 / 5 (2) Nov 07, 2011
antialias_physorg
..Putting out some loony theory 'because it sounds good' is not how great scientists work.

Well then why should I worry? Anyway, New developements: an idea about the cyclical U.

For argument only (don't get uptight about looney theories): First I assume positrons are subject to anti-gravity and electrons to gravity. A safe assumption because if positrons were not subject to anti-gravity black holes would never evaporate. So when all matter decays or gets swallowed up in black holes it will eventually be converted to radiation and evaporate. We can avoid talking about negative energy:
Seeker2
1 / 5 (2) Nov 07, 2011
cont...
As electrons (matter) are pulled into the black hole they radiate because they are accelerated. The energy for their acceleration comes from the gravitational field inside the black hole. So effectively their charge converts gravitational energy into radiation. All of this radiation may not immediately escape from the black hole but as the event horizon collapses shorter and shorter wavelengths (higher energy photons) escape as more and more of their wavelengths become greater than the event horizon.

There is an additional source of radiation from the black hole. As positrons are accelerated away from the black hole they also radiate, converting gravitational energy outside the black hole into radiation.
Seeker2
1 / 5 (2) Nov 07, 2011
cont...
So electrons, although they are mutually repulsive, experience some gravitational attraction and they are collected in the inner regions of spacetime. Photons, which we can consider massless, hang out in the mid regions of spacetime, and positrons experience some gravitational repulsion, so they inhabit the far reaches of spacetime, resulting in a sort of double-barreled Van de Graf generator. A collection of positrons on the outside surface and electrons on the inside surface, separated by photons and perhaps "empty" space.
Now as spacetime continues to contract (lose its internal energy of DE expansion and convert it to heat) eventually you're going to have some contact between the outer regions and the inner regions. Guess what. Lightning strikes, just like the van de Graf generators except this one uses positrons and electrons.
Seeker2
1 / 5 (2) Nov 07, 2011
cont...
Roger Penrose even claims to see signs of a collapsing U in the CMB. Boy is he getting heat for publishing without proper peer review.{:-)

Seeker2
1 / 5 (1) Nov 25, 2011
roboferret:
...If antimatter was repelled by normal matter, antiparticles generated in the accretion disk would be rapidly accelerated away from a black hole, and we could detect large amounts of high energy antiparticles from the the direction of black holes.

Ergo positron particle jets?

...I'm not sure how useful it is to talk about black hole singularities in terms of matter/antimatter anyway.

Speaking of which what is the force of gravity at the center of mass of a black hole? I guess you could have a singularity at the center of mass of a black hole but it would have no gravity and hence no matter?

......There is no evidence yet as to whether antimatter has anti-gravity properties

Well maybe except for positron particle jets ejected from black holes.
Seeker2
1 / 5 (1) Nov 25, 2011
maybe ejected away from black holes.

Seeker2:
...if positrons were not subject to anti-gravity black holes would never evaporate

My guess is if positrons and other anti-matter were subject to gravitational attraction with matter there would be no black holes. Probably no stars and galaxies either.

Now here's an interesting thought: As spacetime continues to expand it loses its mediating power to cause anti-matter to experience anti-gravity. Spacetime energy density less than that of anti-matter means anti-matter begins to sink and aggregate. Anyway once it meets the inner cloud of electrons (even greater energy density than anti-matter) the sparks begin to fly again.

Isn't this fun?

Isn't this fun?
Seeker2
1 / 5 (1) Nov 26, 2011
Actually one fun is enough. Sorry.
Callippo
not rated yet Nov 26, 2011
.There is no evidence yet as to whether antimatter has anti-gravity properties

Well maybe except for positron particle jets ejected from black holes.
There is no evidence yet for positron particle jets ejected from black holes
Seeker2
not rated yet Nov 26, 2011
Seems to be lots of evidence of some kind of particle jets. At least from what I've found on Zooniverse.
Callippo
1 / 5 (1) Nov 26, 2011
Seems to be lots of evidence of some kind of particle jets. At least from what I've found on Zooniverse.
Such proclamation sounds a much better...;-) You've no evidence that a) these jets come from black hole, b) come from inside of black hole c) are formed with positrons.

To be completely clear, I do believe too, the black holes can evaporate antimatter in form of antineutrinos just from their interior, as it belongs into predictions of AWT. But it's prediction, not a postdiction - as we have no evidence for it yet.
Seeker2
1 / 5 (1) Nov 26, 2011
Per http://arstechnic...away.ars
"Scientists are interested in figuring out how the relativistic jets of particles manage to be accelerated away from a black hole, an entity notorious for pulling things in. There have been a number of proposed"

So here's your answer. Black holes push anti-matter (positrons) away, not in.
Seeker2
1 / 5 (1) Nov 27, 2011
Per http://www.physor...066.html "jets may form right outside black holes that have a retrograde spin or which spin in the opposite direction from their accretion disk."

So the accretion disk would be composed of matter being pulled into the black hole, including electrons, whereas jets spin in the opposite direction, indicating opposite charge (positrons) which would be anti-matter.
Callippo
1 / 5 (1) Nov 27, 2011
"Scientists are interested in figuring out how the relativistic jets of particles manage to be accelerated away from a black hole, an entity notorious for pulling things in. There have been a number of proposed"

So here's your answer. Black holes push anti-matter (positrons) away, not in.
This is just a claiming of the same fact in another words. But how exactly they're doing it - if we know, positrons have positive rest mass?
Callippo
1 / 5 (1) Nov 27, 2011
A hint: superluminal neutrinos of recent OPERA experiments..
Black hole spin may create jets that control galaxy
There is another hint: gravitational brightening of massive stars.
Callippo
1 / 5 (1) Nov 27, 2011
Many theories already considered, that the event horizon of fast rotating black holes has a toroidal shape. I.e. it behaves like spherical black hole with hole at event horizon at one or both poles and the energy of black hole can escape through it in form of polar jets. These jets are exaggerated form of gravitational brightening of massive stars.

http://www.aether...ole2.gif

In addition, the center of doughnut has a negative curvature of space-time, so it can expel the particles with negative curvature of surface preferably. I don't think, the positrons can escape through event horizon of black hole directly, but the neutrinos could and they can condense into heavier particles with CMBR outside of black holes. It's an analogy of Howking radiation for neutrinos.
Callippo
1 / 5 (1) Nov 27, 2011
The Hamilton mechanics brings another insight into black hole evaporation. We could consider the event horizon as an analogy of total reflection phenomena, which prohibits the escaping of photons from density gradient of vacuum, which is forming the surface of black hole. Such a photons are reflected back, so that the interior of black hole is behaving like the mirror for short wavelenght photons.

http://www.aether...refl.gif

But at the case of rotating black hole the gradient of space-time density at the polar area is low, so that the light can pass through it in form of polar jets. Because the observable Universe appears like the interior of black hole, this model is even testable. We could observe the reflection of distant stars from internal walls of Universe (compare the "hall of mirrors" model in this connection).

http://www.scienc.../enlarge

And the WMAP cold spot can serve as the hole in our Universe.
Seeker2
1 / 5 (1) Nov 27, 2011
"Scientists are interested in figuring out how the relativistic jets of particles manage to be accelerated away from a black hole, an entity notorious for pulling things in. There have been a number of proposed"

So here's your answer. Black holes push anti-matter (positrons) away, not in.
This is just a claiming of the same fact in another words. But how exactly they're doing it - if we know, positrons have positive rest mass?

Positrons have positive energy density, but less than spacetime. Also evidence about the spin at: http://www.physor...066.html "jets may form right outside black holes that have a retrograde spin or which spin in the opposite direction from their accretion disk."
So the accretion disk would be composed of matter being pulled into the black hole, including electrons, whereas jets spin in the opposite direction, indicating opposite charge (positrons) which would be anti-matter.
Callippo
1 / 5 (1) Nov 27, 2011
So the accretion disk would be composed of matter being pulled into the black hole, including electrons, whereas jets spin in the opposite direction, indicating opposite charge (positrons) which would be anti-matter.
Id rather say, the jets are full of antineutrinos, from which the positrons are condensing with their interaction with vacuum, but basically yes, it's correct insight. And it fits the vortex models of elementary particles, like the electron. The black hole would behave like giant elementary particle, after then.

http://www.aether...anim.gif

http://members.ch...tron.pdf

The escaping of antiparticles from black holes fits well some recent observations too.

http://www.dailyg...ay-.html
Seeker2
1 / 5 (1) Nov 27, 2011
Callippo: I don't think, the positrons can escape through event horizon of black hole directly

Note positrons wouldn't be being affected by the event horizon if they experience anti-gravity.
Callippo
1 / 5 (1) Nov 27, 2011
So the accretion disk would be composed of matter being pulled into the black hole, including electrons
IMO both disks can originate from original black - after all, in the same way, like at the case of supernova explosions.

http://www.spacet...719b.jpg

The supernova jets differ from those of black hole just with their wider angle, but the geometric similarity of both artifacts is quite apparent.

http://www.aether...ova1.gif
Callippo
1 / 5 (1) Nov 27, 2011
positrons wouldn't be being affected by the event horizon if they experience anti-gravity
IMO all particles heavier than neutrinos will be broken with gravity field at the event horizon. It makes no problem, as these particle can materialize from photons and anti/neutrinos just behind the event horizon at the safe distance from it in the same way, like the vapor is condensing into fog after cooling just above the tea cup. The low gravity field (stress energy tensor) serves as a low temperature gradient here, because the gravitational rip is reversible. http://en.wikiped...fication
Seeker2
3 / 5 (2) Nov 27, 2011
Callippo: IMO all particles heavier than neutrinos will be broken with gravity field at the event horizon

I understand all particles are ripped apart into their constituents as they are accelerated into the BH. The densest parts would then occupy the cener part (sort of like occupy Wall Street). Sorry I couldn't resist that.

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