Collapse of physics, quantum mechanics not reconcilable with general relativity

[sdowney717]

yet nature does operate and not by sets of rules we understand.
the discovery of black holes means we dont fully understand anything.

http://www.youtube.com/watch?v=wHHz4mB9GKY&feature=related

Quite a conundrum these physics people have discovered.

I look at it as the more you know, the more you realize how little you know.

[neu5eeCh]

Well -- you'll get at least one respondent, that's me, who has a passion for this subject (at an amateur level).

One of the aspects that the video, curiously, never mentions is that no one really knows what gravity is! We can beautifully describe, with atomic accuracy, gravity's behavior; but physics doesn't know what constitutes gravity. The graviton is a hypothetical particle that "expresses" gravity, but science hasn't yet confirmed its existence. Until science understands what gravity is, I'm not so sure we should be all that concerned by the contradictions in Einstein's Relativity and QM.

Interestingly, there's a category of stars that might come between neutron and black hole -- a quark star (http://en.wikipedia.org/wiki/Quark_star). Before quarks were identified, no one thought that quark stars might exist. If there are constituent particles that make up quarks, then I've always wondered if it's possible that a star, (that might appear to be a black hole from the outside), actually has a surface composed of these sub-quark particles. In other words, there might be no such thing as a singularity, just another kind of star whose surface is composed of ever more fundamental building blocks.

[Smilax]

well, their may be undiscovered territory beyond the quark, however once an object is contained inside an event horizon it does not matter what it's made of. all paths lead to the singularity. to stay in a stable arrangement a star would have to violate the speed of light with respect to it's local spacetime. which it cannot do.

[Bandit]

One of the aspects that the video, curiously, never mentions is that no one really knows what gravity is! We can beautifully describe, with atomic accuracy, gravity's behavior; but physics doesn't know what constitutes gravity. The graviton is a hypothetical particle that "expresses" gravity, but science hasn't yet confirmed its existence. Until science understands what gravity is, I'm not so sure we should be all that concerned by the contradictions in Einstein's Relativity and QM..........

You nailed it.


The problem is with everything is that science believes there is a such thing as gravity. You through gravity out the window and replace it with pressure from space/time things start to add up and gen relativity and quantum mechanics start to work together.
This may seem strange and crazy, but hey everyone swore the world was flat 200 years ago and not to long ago everyone thought we was the center of the universe. So think of this. A diver straps some weight on him and swims down 50 feet to do some sight seeing. This same diver swims deeper and deeper off a reef cliff. Well if pressure doesnt kill the diver, but lets say it doesnt for arguments sake. If he dives to deep the pressure from the water will start to make him sink further down. Did his weight change? No.. Water pressure is forcing him down. The same with us on the planets surface except its more pressure on us from Space/time. Matter distorts spacetime. The the density of matter determines how much it distorts spacetime. We observe this force as gravity. But its an effect, not a cause for you seeing yourself being glued to the ground. The further away from dense matter the less the curvature of spacetime is being bent and thus we observe this as less gravity. But remember there is no gravity. If you take this into account, then blackholes and the idea behind the bigbang theory fall into place. Mind you I dont believe there is a single big bang, but many of them going on all the time. Were just to far away to notice any of them other then ours. But thats another discussion. Now Hawkings speculates that all matter is lost in a blackhole. Well he is wrong, matter is not lost, it is still there but is has lost its identity. As in all matter becomes blackmatter. Highly dense, supper hot matter that is so dense that light can not escape. The size of the blackhole is proportional to its density. Though this is hard to measure due to matter always collapsing on itself. But I speculate that since Time is always moving forward, that at some point matter gets to dense that is slows time down to a crawl so much that right before time stops, it causes the matter of the blackhole to explode. Much like a fuse blowing when its being overloaded. Now when this happens it follows the law the each action has an opposite but equal reaction. Thus since very high pressure from spacetime slows down time, an equal reaction of this event would drop the pressure momentarily just long enough that time moves so fast for a slit instance that all matter in the blackhole is thrown outward and evenly away from the event. Thus that explains big bang theory's.

Cheers,
Joe :D

[sdowney717]

The universe is smooth and even, that is the distribution of galaxies where ever you look on a large scale. To me this is a very profound statement. If you turn time backwards towards the point of origin this implies that this distribution was already present at the beginning of all things.

http://www.youtube.com/watch?v=dG1JpC5jels&feature=relmfu

[neu5eeCh]

well, their may be undiscovered territory beyond the quark, however once an object is contained inside an event horizon it does not matter what it's made of. all paths lead to the singularity. to stay in a stable arrangement a star would have to violate the speed of light with respect to it's local spacetime. which it cannot do.

Only according to the Theory of Relativity (as we currently have it) which, as the video demonstrates, ceases to function inside a black hole. So... what you say is based on a theory that doesn't appear to work in a black hole.:popcorn:

[neu5eeCh]

The universe is smooth and even

Maybe.

1.) This remains an informed hypothesis based on the observable universe (which represents a mere fraction of a fraction of a fraction of the whole). In other words, the assertion may also be untrue.
2.) The majority of the observable universe consists of vast holes, inconceivably vast spaces of absolute emptiness, interspersed with filamentary strings of matter. The universe is not smooth or even, descriptions which aren't the same as homogeneous or isotropic. However, even the cosmological principle of homogeneity and isotropy is only theoretical.


If you turn time backwards towards the point of origin this implies that this distribution was already present at the beginning of all things.

http://www.youtube.com/watch?v=dG1JpC5jels&feature=relmfu

Possibly. My understanding is that the distribution of matter is currently thought to be the result of quantum fluctuations during the first 'nth of a second after the Big Bang.

[Favux]

Well the title and caption on the video are totally misleading but other than that the video is an interesting if brief and incomplete description of how physics has been since quantum mechanics was formulated about 80 years ago. So nothing new other than the "confirmation" of black holes.

It does appear true the "Nature is smarter than we are" because we can't come up with quantum gravity or whatever it is that gives us a theory that handles both quantum mechanics and general relativity/gravity.

That actually may be the problem, we just aren't smart enough.

Hopefully it is the lack of the appropriate mathematical tool(s) or key insight(s). Certainly this problem is what string theory has been trying to address for 20-30 years and not getting there.

Some fun books to read to get you up to speed are Lee Smolin's "The Trouble with Physics" and "Three Roads to Quantum Gravity" and Peter Woit's "Not Even Wrong". And there are many others of course.

Planck density is pretty huge, I've wondered what the Panck radius of an object with several solar masses would actually be. Of course treating a physical object as if it has a "point" radius, where a point is a mathematical concept, leads to problems like infinities.

So if String theory is a dead end and adding dimensions isn't the answer what is? By the way there was reason to believe adding dimensions wasn't a good idea from theories going back to shortly after General Relativity came out. The extra dimensions always seem to lead to infinities. And as far as we know there are only 3 dimensions with space/time adding a sort of fourth dimension.

Maybe Loop quantum gravity has some insights to add to String theory. I personally favor the idea that is our understanding of time that is one of the major problems/faulty assumptions. Once we get a better handle on time, maybe quantize it, we'll be a big step forward.

[neu5eeCh]

That actually may be the problem, we just aren't smart enough.

I'm not worried. That's why god gives us geniuses. I'm sure, once the groundwork is laid, another Einstein will show up.


...treating a physical object as if it has a "point" radius, where a point is a mathematical concept, leads to problems like infinities.

When the scientist says "...in the real world infinities don't exist"... that's when he went from being a scientist to an amateur stating yet another belief in accordance with a belief system. Fact: We don't know if infinity exists in the real world anymore than "life after death" or, more neutrally, non-local consciousness.


So if String theory is a dead end and adding dimensions isn't the answer what is?

Is it dead? I haven't paid much attention to it since it hasn't made a single testable prediction. I tried reading "The Elegant Universe" but found it so dull and poorly written I couldn't finish it.

[sdowney717]

Smoothness is a cosmological concept.
http://preposterousuniverse.com/writings/cosmologyprimer/overview.html

Fortunately, on the largest scales the distribution of galaxies is very similar throughout the universe; this is what is meant by the smoothness of the universe.

Deep field and ultra deep field views of the Hubble where it was pointed at what was thought to be empty space turned up many tens of thousands of Galaxies, and beyond that? Likely many more.

a 3d view

http://www.youtube.com/watch?v=oAVjF_7ensg&feature=relmfu

[ratcheer]

Has anyone mentioned dark matter, yet? That seems to me to be the gaping hole in modern physics. Vast quantities of additional matter are required for the universe to work, based on current theories, but what it is or where it is is still completely unknown.

Tim

[Smilax]

Only according to the Theory of Relativity (as we currently have it) which, as the video demonstrates, ceases to function inside a black hole. So... what you say is based on a theory that doesn't appear to work in a black hole.:popcorn:

this is untrue, the video clearly states that the equations break down at the point where r = 0, i'e the centre of the black hole. so, for a star composed of any matter to exist in a stable arrangement inside the event horizon it would have to violate the speed of light with respect to it's local spacetime. which it cannot do.

an interesting point is that in the case of a rotating black hole (all black holes?) the singularity would have a ring shape, and not be located at r = 0. in this case the gravity field at r = 0 would not be infinite.

[neu5eeCh]

this is untrue, the video clearly states that the equations break down at the point where r = 0...

Yes, I know; but you can't just ignore the assumptions (the equations if you will) that get you to this point.


i'e the centre of the black hole. so, for a star composed of any matter to exist in a stable arrangement inside the event horizon it would have to violate the speed of light with respect to it's local spacetime. which it cannot do.


According to a theoretical framework that ends in (according to the video) absurdity. I'm just saying. You can't cherry-pick the moment at which Einstein's Theory of Relativity is reduced to an "absurdity". Or maybe you can? I don't know.


...an interesting point is that in the case of a rotating black hole (all black holes?) the singularity would have a ring shape, and not be located at r = 0. in this case the gravity field at r = 0 would not be infinite.

It's all utterly hypothetical at this point. ;)

[neu5eeCh]

Has anyone mentioned dark matter, yet? That seems to me to be the gaping hole in modern physics. Vast quantities of additional matter are required for the universe to work, based on current theories, but what it is or where it is is still completely unknown.

Tim

Dark matter seems to be an accepted "fact" (especially the way one hears it discussed at the popular science level). Curiously, though, the evidence for its existence is purely, utterly and entirely circumstantial. No one anywhere, at any time, has found "dark matter" or described its properties in any verifiable way. The whole hypothesis could, potentially, turn out to be utterly and magnificently wrong.

In short, the way scientists talk about dark matter (as accepted and even established fact) is entirely misleading. It's weird. A little more humility would seem to be in order.

[Smilax]

Yes, I know; but you can't just ignore the assumptions (the equations if you will) that get you to this point.




According to a theoretical framework that ends in (according to the video) absurdity. I'm just saying. You can't cherry-pick the moment at which the relativity is reduced to an "absurdity". Or maybe you can? I don't know.



It's all utterly hypothetical at this point. ;)


it's not cherrypicking, the equations really do work fine untill you get to r = 0 point.

for example, for a sufficiently large black hole you would be unaware of even crossing the event horizon.

[Smilax]

Dark matter seems to be an accepted "fact" (especially the way one hears it discussed at the popular science level). Curiously, though, the evidence for its existence is purely, utterly and entirely circumstantial. No one anywhere, at any time, has found "dark matter" or described its properties in any verifiable way. The whole hypothesis could, potentially, turn out to be utterly and magnificently wrong.

In short, the way scientists talk about dark matter (as accepted and even established fact) is entirely misleading. It's weird. A little more humility would seem to be in order.



a direct empirical proof of the existence of dark matter

http://arxiv.org/abs/astro-ph/0608407

[Gremlinzzz]

Every galaxy has a blackhole in its center or so i read.what would cause a blackhole to be in the center? does it explode creating the galaxy then attempt to vacuum it all back .How sure are we that they exist! {I'll call my theory the bathtub effect} :popcorn:

[neu5eeCh]

a direct empirical proof of the existence of dark matter

http://arxiv.org/abs/astro-ph/0608407

OK, the Bullet Cluster, but then there's this (http://en.wikipedia.org/wiki/Bullet_Cluster):



Mordehai Milgrom (http://en.wikipedia.org/wiki/Mordehai_Milgrom), the original proposer of MOND (Modified Newtonian Dynamics (http://en.wikipedia.org/wiki/Modified_Newtonian_Dynamics)), has posted on-line a refutation[15] (http://en.wikipedia.org/wiki/Bullet_Cluster#cite_note-14) of claims that the Bullet Cluster proves the existence of dark matter. Milgrom claims that MOND correctly accounts for the dynamics of galaxies outside of galaxy clusters, and even in clusters such as the Bullet Cluster it removes the need for most dark matter, leaving only a factor of two which Milgrom expects to be simply unseen ordinary matter (non-luminous baryonic matter (http://en.wikipedia.org/wiki/Baryonic_dark_matter)) rather than cold dark matter (http://en.wikipedia.org/wiki/Cold_dark_matter). Without MOND, or some similar theory, the matter discrepancy in galaxy clusters is a factor of 10, i.e. MOND reduces this discrepancy five-fold to a factor of 2. Whilst another study in 2006[16] (http://en.wikipedia.org/wiki/Bullet_Cluster#cite_note-15) cautions against "simple interpretations of the analysis of weak lensing in the bullet cluster", leaving it open that even in the non-symmetrical case of the Bullet Cluster, MOND, or rather its relativistic version TeVeS (Tensor–vector–scalar gravity (http://en.wikipedia.org/wiki/Tensor%E2%80%93vector%E2%80%93scalar_gravity)), could account for the observed gravitational lensing.

The Bullet Cluster is definitely evidence, but it doesn't seem to be conclusive evidence of "Dark Matter". Dark Matter remains hypothetical. And remember, we don't even know what gravity is!

[neu5eeCh]

it's not cherrypicking, the equations really do work fine untill you get to r = 0 point.

:lolflag: And that used car worked just fine until you tried to drive it. What evidence do you have that the equations work just fine until r=0? None. Nobody knows what's behind the event horizon -- all we have are theoretical models. A little humility is called for.

[Smilax]

Every galaxy has a blackhole in its center or so i read.what would cause a blackhole to be in the center? does it explode creating the galaxy then attempt to vacuum it all back .How sure are we that they exist! {I'll call my theory the bathtub effect} :popcorn:

evidence for black holes at the center of galaxy's comes from

1 - motion of stars in the central region of our galaxy

2- AGN, active galactic nucleus. emission of xrays from other galaxy's. this is thought to be the result of blackbody radiation from a material with a temperture of 10's of millions of degrees. the material reaches such a temperture by friction caused by it's accreation into a black hole. also synchrotion radio emission from 'jets'.

[neu5eeCh]

Every galaxy has a blackhole in its center or so i read.what would cause a blackhole to be in the center? does it explode creating the galaxy then attempt to vacuum it all back .How sure are we that they exist! {I'll call my theory the bathtub effect} :popcorn:

Their existence is inferred. To my knowledge, no one has actually *seen* a black hole in the center of any galaxy but, according to current knowledge, the only object capable of exerting the necessary gravitational pull (and other features) is a black hole.

What would cause a black hole to be in the center? Well -- that goes all the way back to the Big Bang and the quantum fluctuations that created the filaments of matter that eventually collapsed into massive and short-lived super giants (or so the current model holds). These super giants would have readily (literally within millions of years) collapsed into black holes. These black holes eventually became the centers of galaxies, having the gravitational mass to hold the necessary mass together.

[layers]

The video says that Relativity breaks down in the center of a black hole, just because you divide by 0. If that is true, then if we take Newton's gravitational law between two bodies: F=Gm1m1/r^2 would also arrive at the same dilemma, yet, we all know that it works, based on outer-space motion and satellites.

And one more thing: how can you ever get r of 0 between two bodies? To superimpose them on one other? 0, just like infinity is just an idea.

[dpny]

The universe is smooth and even, that is the distribution of galaxies where ever you look on a large scale.

I think what you mean to say is that, on a local level, the universe is isometric and spatially flat.


If you turn time backwards towards the point of origin this implies that this distribution was already present at the beginning of all things.

Not even a little bit. On a local level the universe is isometric. On a macro level, to the best of our ability to know, the universe is also isometric. However, between the two, the universe is aniosmetric--that is, all lumpy and stuff--and curved. As has been said, most of the visible matter in the universe consists of filaments of matter--enormous grouping of galaxies--separated by empty space hundreds of billions of light years across.

[neu5eeCh]

The video says that Relativity breaks down in the center of a black hole...

Or so he claims. Remember, this is all hypothetical. Seriously. From the Event Horizon inward, it's all informed speculation.

[dpny]

Or so he claims. Remember, this is all hypothetical. Seriously. From the Event Horizon inward, it's all informed speculation.

It isn't informed speculation: the math is rigorous, and relativity is one of the most tested theories we have. It's better to say that as you get close to the singularity you need something beyond relativity to accurately describe what happens.

[Smilax]

:lolflag: And that used car worked just fine until you tried to drive it. What evidence do you have that the equations work just fine until r=0? None. Nobody knows what's behind the event horizon -- all we have are theoretical models. A little humility is called for.





einstiens equations are some of the most tested we have

Tests of General Relativity

Bending of starlight
Deviation of the orbit of Mercury from Newtonian prediction
Gravitational redshift
Change of the period of a binary pulsar
Gravitational waves (coming soon!)

i think you'r having problems understanding the nature (or lackthereof) of an event horizon. it's not a real place or thing, (however it may be thought of having a temperture, but when you think deeply u will see this isn't a contradiction), their is no reason why the laws of physics should be different either side of one.

for example, we are currently inside the event horizion of our observable universe, and we can never leave. but we hace no reeason to believe that things are different outside this horizion, why, because this horizon is growing with time, stuff which in the past was inside the horizon, wrt us, is currently ouside.

[Bandit]

Has anyone mentioned dark matter, yet? That seems to me to be the gaping hole in modern physics. Vast quantities of additional matter are required for the universe to work, based on current theories, but what it is or where it is is still completely unknown.

Tim

Hey Tim,
Dark Matter is facinating concept. Now modern theorys postulate that Dark Matter exist do to gravitational annomolies in some celestial bodies. Whats even more exiciting is if you take my theory I am proposing which has gravity taken out of the equation, it shows that not only may exist, but must exist. Very interesting stuff :)

[Favux]

Can you properly say there is any thing outside our event horizon?

It's better to say that as you get close to the singularity you need something beyond relativity to accurately describe what happens.
Exactly. So as Smilax also points out, no one really doubts the validity of General Relativity. And no one really doubts Quantum Mechanics. The hope is that they are incomplete approximations of what is really going on. And once they are extended and made more complete we'll understand how to unify them.

There have been a bunch of great experiments demonstrating quantum mechanics is valid over the last 10-20 years. Including the "spooky action at a distance" that had Einstein so concerned.

General Relativity has also withstood all tests. The black hole issue has been known a long time and is one of the reasons to think it is incomplete. Two other issues everyone knows about look to be observational problems. It took a while to notice the galaxies were rotating faster than their visible mass accounts for, hence dark matter. But how do you observe a chargeless, but not massless, particle? Having no charge means it emits no light and interacts with baryonic matter even less than a neutrino. And the old/new problem of the Cosmologic Constant was also due to observational issues.

[neu5eeCh]

It isn't informed speculation: the math is rigorous, and relativity is one of the most tested theories we have. It's better to say that as you get close to the singularity you need something beyond relativity to accurately describe what happens.

The math is rigorous, but so in Newton's. The math of string theory is rigorous but the universe string theory suggests could be a complete fabrication. Whether the math is rigorous or not is utterly irrelevant. It's better to say that we don't know what happens behind the event horizon and only speak in terms of current hypothetical models.

[neu5eeCh]

But how do you observe a chargeless, but not massless, particle? Having no charge means it emits no light and interacts with baryonic matter even less than a neutrino. And the old/new problem of the Cosmologic Constant was also due to observational issues.

I agree with all that. I'm not saying that the "Dark Matter" hypothesis is wrong. I'm saying that current dogma goes around discussing it as though it were established fact. It's not. It's still just a hypothesis. The evidence is not conclusive and could be suggestive of other possibilities. By comparison, the theory of the Big Bang is all but settled. That there was A Big Bang is no longer in dispute. The nature of the Big Bang, on the other hand, is.

[dpny]

The math is rigorous, but so in Newton's.

And classical mechanics is still alive and well. Probably 95% of the engineering in the world is based on classical mechanics.


The math of string theory is rigorous but the universe string theory suggests could be a complete fabrication. Whether the math is rigorous or not is utterly irrelevant.

The difference being that relativity has been tested again and again and again and has never been disproved, so to assume that it suddenly breaks down on the other side of the event horizon is illogical. Given that, on a large enough black hole, a theoretical astronaut wouldn't even notice passing through the event horizon (the gravity gradient being relatively gentle on big black holes) we can make safe assumptions that relativity holds until the curvature of spacetime becomes extreme, which happens near the singularity.

String theory is in the same position as quantum mechanics was in the early part of the 20th century: it is untestable using current methods. This was Einstein's big issue with it: as a classicly trained physicist he really only trusted things he could model in the laboratory. However, just as the century following the discovery of quantum mechanics has provided the theory and technology to test it, so I am sure the following decades will provide the ability to prove or disprove the various string theories.

I'm surprised no one has mentioned one of the biggest problems with black holes and relativity: the Black Hole information paradox (http://en.wikipedia.org/wiki/Black_hole_information_paradox).

[Smilax]

the amount of ordinary matter produced in the big bang is tightly constrained by primordial nucleosynthesis. and it's not sufficient to produce the current universe in the time available. therefore the very existance of galaxies at this time is evidence for dark matter.

newtons maths is rigorous. but his theory did not stand up to the test. ie, orbit of mercury.
GR does.

we do know what occurs behind an event horizon, we are currently behind an event horizon.

[Favux]

I'm surprised no one has mentioned one of the biggest problems with black holes and relativity: the Black Hole information paradox.
Not sexy and requires way too much explanation. Heck, I'm still not convinced Hawking lost the bet.

we do know what occurs behind an event horizon, we are currently behind an event horizon.
I'd agree if you changed that too:
we do know what occurs behind our event horizon, we are currently behind an event horizon.

[ratcheer]

Curiously, though, the evidence for its existence is purely, utterly and entirely circumstantial. No one anywhere, at any time, has found "dark matter" or described its properties in any verifiable way.

Which is just another way of saying exactly what I said. The "circumstantial" evidence is that the universe would not hold together without a certain amount of gravitational mass. That mass has not been discovered, yet, circumstantially, the universe does hold together.

Tim

[neu5eeCh]

...so to assume that it suddenly breaks down on the other side of the event horizon is illogical....

I'm not saying that it suddenly breaks down. I'm saying that we don't know what happens. Period. It may break down or it may not. We have informed hypotheses, but that's all. The only way you're going to argue your way out of this is to cross an event horizon and send me an E-Mail. That's not going to happen and never will. As we come to better understand gravity, Relativity and QM, we might discover that black holes behave in ways we never imagined.

[effenberg0x0]

I'm also passionate about Physics and Cosmology (just an amateur avid reader). During last years I have read many authors and tried to understand/accept the concept of Strings and M-Theory as much as possible.

With a lot of effort, I can accept the "Quantum Foam" and virtual particles appearing out of nowhere, annihilating, etc as part of the concept of gravity in quantum scale. But when it comes to strings, 11 dimensions, branes, and strings "tying" rips in spacetime at the quantum level, I just can't. Many scientists point out that string theory lacks the mathematical beauty and simplicity that is inherent to nature and expressed in correct/tested theories, like Einstein's and Dirac's work.

String theory can't be put to test in a lab. Neither can multiverse and other highly speculative solutions. It's frustrating that with all the effort of many geniuses and scientists and throughout so many years, we still don't know what time is, we don't know what space is, we don't know what matter is, we don't know what gravity is, we don't know what reality is.

I hope to see some answers to these questions in the next 50 years or so, before I die :)

Regards,
Effenberg

[Chronon]

yet nature does operate and not by sets of rules we understand.
the discovery of black holes means we dont fully understand anything.

http://www.youtube.com/watch?v=wHHz4mB9GKY&feature=related

Quite a conundrum these physics people have discovered.

I look at it as the more you know, the more you realize how little you know.

I just saw this topic and haven't read the whole thing yet. However, nothing in your post should be surprising. Nothing in science is fully understood. Nature doesn't operate according to science. Science is our attempt to understand nature. Nature doesn't actually care what science says.

The inconsistency between general relativity and QM has been known for quite a long time.

[neu5eeCh]

I'd agree if you changed that too:
we do know what occurs behind our event horizon, we are currently behind an event horizon.

I've read about that theory and I love it. I love the thought that each black hole creates a new universe. O:)

ratcheer writes: Which is just another way of saying exactly what I said. The "circumstantial" evidence is that the universe would not hold together without a certain amount of gravitational mass. That mass has not been discovered, yet, circumstantially, the universe does hold together.

No, not quite. It's possible that there isn't "more mass". It's possible, and some argue, that the laws of gravity behave differently over long distances. The evidence doesn't yet eliminate this possibility, though the scientific community (in general it seems) strongly resists this explanation. I don't have a dog in the hunt; but I would point out that the "scientific community" has, en masse, been wrong before.

[dpny]

I'm not saying that it suddenly breaks down. I'm saying that we don't know what happens. Period. It may break down or it may not. We have informed hypotheses, but that's all. The only way you're going to argue your way out of this is to cross an event horizon and send me an E-Mail.

No: you don't seem to understand how this works. Theories allow us, by definition, to make educated guesses about things of which we are ignorant. This is exactly what quantum mechanics did: at the time it was proposed it was almost completely untestable and was fought against fiercely by Einstein and others, some of whom claimed that it was all just untestable math. However, as I said, in the follow decades it was tested and has been repeatedly proved.

Hypothesizing what goes on beyond the event horizon is precisely why we have theories like relativity, and making assumptions from those theories is exactly how knowledge progresses. Until someone comes up with a mathematically rigorous reason as to why relativity suddenly ceases on the other side of the event horizon--and no one has been able to do that in the last 100 years--there is no reason to say we should stop our guesses at the event horizon.

Mathematically, there is nothing special about an event horizon. It is merely an area in spacetime beyond which all like timelines converge to the same point.

[Smilax]

well, we do know,

if the tidal radius is contained inside the event horizion crossing the event horizion is unnoticed by a local observer. however, the local observer does notice when he gets to the tidial radius, cause it hurts.

when the other situation occurs the local observer is dead by the time he reaches the event horizion.

but anyway, i'm sure you know that by definition emails can't be sent across event horizons.
so asking for an impossible to change your views is really more religion than science, but hey, whatever.

[neu5eeCh]

I hope to see some answers to these questions in the next 50 years or so, before I die :)

Have had a Near Death Experience, I'm holding out for the whole enchilada after I die. ;)

[neu5eeCh]

Theories allow us, by definition, to make educated guesses about things of which we are ignorant

And with the words "educated guesses", we can put this disagreement to rest. That's my point. What goes on behind the event horizon is an "educated guess". What may (with our limited knowledge) presently look like a perfectly logical and acceptable model of a black hole's innards, may turn out quite differently as our guesses become more educated.

[Smilax]

And with the words "educated guesses", we can put this disagreement to rest. That's my point. What goes on behind the event horizon is an "educated guess". What may (with our limited knowledge) presently look like a perfectly logical and acceptable model of a black hole's innards, may turn out quite differently as our guesses become more educated.

it's really not, we are behind an event horizon, we can see what happens.

i think you should really think on the nature of an event horizon. or not, it's up to you.

[iponeverything]

I love the Science Channel. Whenever I start to feel small, I turn it on and it puts everything back into perspective.

A fascinating discussion I watched yesterday was about the long standing belief of the string community in 10 dimensions and how the theory was in trouble because of the appearance multiple versions. Apparently when an 11th dimension was incorporated, the competing versions turned into alternate manifestations. I don't remember all the details, but the show went to some detail of M theory and how some scientist are using this 11 dimensional model to explain gravity. The theory is that our gravity is diluted gravity bleeding over from another dimension.

I find this quest science is on to peel back the fabric of reality, to be really cool. Jeez - to invest so much time and treasure into the LHC - which on the surface, appears to have a zero chance of producing practical knowledge, to be on one level baffling and on another amazing.

I see it like a kid shooting a bb gun at a window. If he hits it just right, maybe it will stop just knocking chips off - and shatter it.

[dpny]

And with the words "educated guesses", we can put this disagreement to rest. That's my point. What goes on behind the event horizon is an "educated guess". What may (with our limited knowledge) presently look like a perfectly logical and acceptable model of a black hole's innards, may turn out quite differently as our guesses become more educated.

As has been pointed out, we live in an event horizon. Mathematically speaking, there is no difference between the event horizon in which we live and the event horizon around a singularity. Relativity holds right up until the singularity, when the curvature of spacetime gets extreme. So, while we are likely to find new and exciting things about the singularity--a fuzzball (http://en.wikipedia.org/wiki/Fuzzball_(string_theory)), perhaps--what we know about event horizons likely won't change much.

[neu5eeCh]

it's really not, we are behind an event horizon, we can see what happens.

i think you should really think on the nature of an event horizon. or not, it's up to you.

Furthermore, when the video says that we know there's no such thing as infinity in the real world, I know he's wrong because my stupidity has an event horizon from which nothing can escape and which, at its core, is infinite.

[dpny]

Furthermore, when the video says that we know there's no such thing as infinity in the real world, I know he's wrong because my stupidity has an event horizon from which nothing can escape and which, at its core, is infinite.

An event horizon is not infinite. It is simply an area of space time and can be measured quite easily. The event horizon around the black hole in the center of our galaxy has a radius of no more than 6.25 light hours.

[Smilax]

i agree, the first part only i mean ;)

the universe its self may be infinite

[neu5eeCh]

An event horizon is not infinite.

I was referring to the point at which my stupidity becomes a singularity and divisible by zero. ;)

[Smilax]

well QM describes the small stuff, and GR is the limit of big stuff,

however, it really is quantum all the way up.


so if you look at it this way, there is no trouble between QM and GR.

GR is limiting case of quantum at large scale.

which by definition, means it's not apply to small scale.

and the inbetween bit, well, that's just maths, :popcorn:

[Favux]

Wow, nice work Smilax. A little hand waving and we're there! :)

VTPoet what you're saying about dark matter is basically correct. It's probably the phrasing that's pushing some buttons. Because there are challenges to General Relativitely. One, MOND, has already been cited with regards to the bullet cluster (http://en.wikipedia.org/wiki/Bullet_Cluster). But the general consensus and overwhelming evidence is for GR. So given what we currently have (and Occam's Razor) dark matter best fits. But hey, it could be wrong.

[Gremlinzzz]

When do you reach nothingness even nothing is something.does a flea have fleas?do the fleas on the flea have fleas?the universe is expanding into what? where does it stop and begin?what is it?Not meant to be answered just questioned.
:popcorn:

[Gremlinzzz]

I found it:popcorn:
The Answer to the Ultimate Question of Life, The Universe, and Everything.

[neu5eeCh]

VTPoet what you're saying about dark matter is basically correct. It's probably the phrasing that's pushing some buttons. Because there are challenges to General Relativitely. One, MOND, has already been cited with regards to the bullet cluster (http://en.wikipedia.org/wiki/Bullet_Cluster). But the general consensus...

Yes.


...and overwhelming evidence is for GR.

No.

The overwhelming evidence does not support GR. The evidence is open to more than one interpretation and does not, by any stretch of the imagination, overwhelmingly support anything one way or the other.

As an example, look here (http://www.astro.umd.edu/%7Essm/mond/mondvsDM.html). Or here (http://news.sciencemag.org/sciencenow/2011/02/more-evidence-against-dark-matte.html). From what I can tell, these aren't fringe scientists. Science in general, however, is known for herd mentality.


So given what we currently have (and Occam's Razor) dark matter best fits. But hey, it could be wrong.

In fact, according to my reading, that's an argument against DM.

[Favux]

Science in general, however, is known for herd mentality.
Humans in general, however, are known for their herd mentality.

Admittedly a wee bit insulting because humans aren't grazing animals. And by extension nor are scientists.

It depends on how you interpret the data and how much weight you apply to various things. But ultimately you have to make judgements. It seems necessary that the onus is on the challengers. Something about extraordinary claims requiring extraordinary evidence. Of course from your perspective it is not an extraordinary claim and there lies the rub.

[neu5eeCh]

As has been pointed out, we live in an event horizon. Mathematically speaking, there is no difference between the event horizon in which we live and the event horizon around a singularity.

If you're talking about the Hubble Sphere and comparing it to an Event Horizon, then no, they're not the same, not mathematically speaking and not in any other sense.

[Smilax]

If you're talking about the Hubble Sphere and comparing it to an Event Horizon, then no, they're not the same, not mathematically speaking and not in any other sense.


he's not

[neu5eeCh]

It seems necessary that the onus is on the challengers. Something about extraordinary claims requiring extraordinary evidence. Of course from your perspective it is not an extraordinary claim and there lies the rub.

Challengers? Perspective? That's not a frame I'm going to get drawn into because it's irrelevant. My perspective (anyone's perspective) is irrelevant. The only question is what the evidence suggests. The evidence does not overwhelmingly suggest DM. The evidence can equally (and with greater success in some cases) suggest other possibilities. I don't have a dog in the hunt, by the way. If DM turns out to be correct, then I'll climb aboard; but there seems to be a bit of denial in these comments. The problem is in wanting to believe a theory with insufficient evidence. That is the rub.

[neu5eeCh]

Here's (http://www.msnbc.msn.com/id/47118181/ns/technology_and_science-science/t/question-if-not-dark-matter-then-what/) a 6 day old article (according to Google) that begins:


Astronomers mapped the motions of hundreds of stars in the Milky Way in order to deduce the amount of dark matter that must be tugging on them from the vicinity of our sun. Their surprising conclusion? There's no dark matter around here.



As the researchers write in a forthcoming paper in the Astrophysical Journal, the stellar motion implies that the stars, all within 13,000 light-years of Earth, are gravitationally attracted by the visible material in our solar system — the sun, planets and surrounding gas and dust — and not by any unseen matter.


"Our calculations show that (dark matter) should have shown up very clearly in our measurements. But it was just not there!" said lead study author Christian Moni-Bidin, an astronomer at the University of Concepcion in Chile.

If the analysis of the data from Chile's European Southern Observatory (ESO) is correct — a big "if," several physicists say — it overturns the decades-old theory that dark matter permeates space in our region of the Milky Way.

[Favux]

lol I'm trying to conceed the validity of some of your arguments and calm the waters. Instead I'm agitating them. I must be really bad at agreeing.

I'd like to refrain from stirring things up further, but I can not resist this observation. You can not on one hand complain about herd mentality and on the other say:

My perspective (anyone's perspective) is irrelevant.

[neu5eeCh]

...I can not resist this observation. You can not on one hand complain about herd mentality and on the other say:

Not sure I see your point? The herd mentality displayed by scientists at various times is often because ego and perspective trumped evidence and the scientific method. That's why I say that perspective is irrelevant. I really don't have a perspective on what is an extraordinary claim and what isn't. I just read the same thing everyone else reads -- and what that tells me is that scientists who talk about DM (as though it were established fact) are misleading the public. I can't tell you how many popular science programs I've watched that discuss DM as though they were talking about an earth that's round. If DM turns out to be just plain wrong, there's going to be so much crow on the menu the bird will go extinct.:popcorn:

[BeRoot ReBoot]

yet nature does operate and not by sets of rules we understand.
the discovery of black holes means we dont fully understand anything.

http://www.youtube.com/watch?v=wHHz4mB9GKY&feature=related

Quite a conundrum these physics people have discovered.

I look at it as the more you know, the more you realize how little you know.


This video reeks of "quantum mysticism" and pseudo-religious nonsense. Please pretend it didn't exist, and learn to tell the difference between actual science and nonsense like this in the future.

[Chronon]

I thought this was about QM vs GR. Why are people talking about dark matter?

[BeRoot ReBoot]

I thought this was about QM vs GR. Why are people talking about dark matter?

Because almost every internet user has their own personal hypothesis about how the universe works that they can't help but share with other people. Usually, their eagerness to tell everyone about it and their confidence in its absolute correctness is inversely proportional to their actual education in physics and mathematics.

[Chronon]

What a statement on human nature! :lolflag:

[Bandit]

Because almost every internet user has their own personal hypothesis about how the universe works that they can't help but share with other people. Usually, their eagerness to tell everyone about it and their confidence in its absolute correctness is inversely proportional to their actual education in physics and mathematics.

Well thats not very nice.. Personally my superiority complex was gained while in the military, internet had nothing to do with it. :lolflag:

[Favux]

lol Perhaps not so nice.

Has anyone noticed we've strayed even further from Quantum Gravity, i.e. the dichotomy between General Relativity and Quantum Mechanics? Or is it just me?

So perhaps rather than snide remarks something informative, or interesting, or some such...

[neu5eeCh]

Has anyone noticed we've strayed even further from Quantum Gravity, i.e. the dichotomy between General Relativity and Quantum Mechanics?

There's so much opinion on the subject, on the Internet, that it's hard to sort out what is fact and what's not. From what I can gather, the "dichotomy" between GR and QM isn't one in which the two theories are fighting over the same terrain. GR deals with large scale phenomena. QM deals with atomic and sub-atomic phenomena -- the "microworld" as one writer calls it. The two only seem to conflict in the extremities -- such as big bangs and black holes. Does that count as contradicting each other? I don't know. My sense is that the question more often asked is not: why do they contradict? -- but why GR can't be extended to the "microworld" and QM to the "macro-world" - (or can it, as some more mystical writers and physicists seem to suggest).

[Chronon]

Neither QM or GR are true in any sort of ontological sense. They are both successful theories in the sense that both have been used to successfully describe a wide range of phenomena. They simply don't seem to be mathematically compatible. So, obviously we should look for a new model that does better.

Unfortunately, inventing new models is hard. You can't just use logic. You need insight or intuition. What more is left to discuss?

[Favux]

Unfortunately, inventing new models is hard. You can't just use logic. You need insight or intuition. What more is left to discuss?
Hard to argue with but a bit of a wet blanket.

Anyone think CERN will offer new insight? Or maybe quantum computing if they can get it working and add it to the toolkit?

[Chronon]

Sure, CERN could provide some new discoveries. Running experiments is how we actually advance the science. There have been some hints of a new particle (maybe the Higgs) at the LHC and the Tevatron already.

I'm more interested in quantum simulation than quantum computing per se. It also has less stringent requirements than a universal quantum computer. Basically, you use one quantum system to simulate the evolution of another quantum system. While you can do quantum simulations on a quantum computer, my understanding is that the requirements are often less stringent than a full-blown universal quantum computer.

[Chronon]

There's so much opinion on the subject, on the Internet, that it's hard to sort out what is fact and what's not. From what I can gather, the "dichotomy" between GR and QM isn't one in which the two theories are fighting over the same terrain. GR deals with large scale phenomena. QM deals with atomic and sub-atomic phenomena -- the "microworld" as one writer calls it. The two only seem to conflict in the extremities -- such as big bangs and black holes. Does that count as contradicting each other? I don't know. My sense is that the question more often asked is not: why do they contradict? -- but why GR can't be extended to the "microworld" and QM to the "macro-world" - (or can it, as some more mystical writers and physicists seem to suggest).

They don't contradict each other as much as they are simply incompatible. Performing canonical quantization (or any other quantization procedure as far as I know) breaks the GR equations.

If you extend QM to the macro-world you tend to lose all of the quantum behavior. Coherence (phase information) goes away and you are left with classical probabilities. It also doesn't magically give you a way to predict gravitational effects.

[alexfish]

Neither QM or GR are true in any sort of ontological sense. They are both successful theories in the sense that both have been used to successfully describe a wide range of phenomena. They simply don't seem to be mathematically compatible. So, obviously we should look for a new model that does better.

Unfortunately, inventing new models is hard. You can't just use logic. You need insight or intuition. What more is left to discuss?

Add a bit of this , to the boiling Pot or Point , depending on there theorem , or theory

http://www.pbs.org/wgbh/nova/physics/absolute-hot.html

[Favux]

Nice alexfish. That was a fun read.

[jonnyboysmithy]

I'm not to much into this stuff but someone who was told me to watch "Crossing the Event Horizon - The Search for the Fundamental Pattern" by Nassim Haramein.
Pdf download also very interesting:http://thepiratebay.se/torrent/7044342/Aether_-_The_Physicalists__God_%28Kindle__Mobi__Epub__Word __HTML_

[Favux]

Hi jonnyboysmithy,

Thanks for your contribution but on this thread we're more interested in the contending theories of quantum gravity. In other words a theory that accommodates both General Relativity and Quantum Mechanics. So more interested in the hard scientific stuff, not so much the spiritual side of things.

[juancarlospaco]

QUESTION:
What will happen if you take 2 equal Black Holes and make them Collision together on opposite direction ?

YOUR ANSWER: ...

[neu5eeCh]

Hi jonnyboysmithy,

Thanks for your contribution but on this thread we're more interested in the contending theories of quantum gravity. In other words a theory that accommodates both General Relativity and Quantum Mechanics. So more interested in the hard scientific stuff, not so much the spiritual side of things.

Yeah. Thanks alot Jonnyboysmithy. I was just about to formulate Quantum Gravity when your soft scientific post distracted me. Now it's gone. It's just gone. I'm devastated.

[neu5eeCh]

QUESTION:
What will happen if you take 2 equal Black Holes and make them Collision together on opposite direction ?

YOUR ANSWER: ...

You get some really impressive gravity waves that highly sophisticated sensors are presently hoping to detect.

[sdowney717]

You get some really impressive gravity waves that highly sophisticated sensors are presently hoping to detect.

here is a picture where 2 galaxies collided and then moved apart spawning a ring of black holes and new stars. the large pink blobs show the black holes where they are sucking in companion star materials

http://www.newscientist.com/blogs/shortsharpscience/2011/02/colliding-galaxies-spawn-dazzl.html
http://www.newscientist.com/blogs/shortsharpscience/2011/02/10/arp147.jpg

[Favux]

Cool pic sdowney717!

[Bandit]

here is a picture where 2 galaxies collided..............
I wonder if any life forms in those glaxies survived? That must have lasted a long time.

[Favux]

Interesting question Bandit.

Of course the distances and timespan are immense, but you don't want to be anywhere near a supernova when it blows. So I would think it would depend on the putative life form's distance from the nearest (presumably) blue giant created in the stellar formation period caused by the two galaxies colliding that went supernova. Also to a certain extent their geometry in relationship to the supernova. Not good if a supernova's polar jet is pointed at you.

Both of those would depend on where they were in their galactic habibility zone (http://en.wikipedia.org/wiki/Habitable_zone#Galactic_habitable_zone), which is a refinement you can add to the basic Drake equation (http://en.wikipedia.org/wiki/Drake_equation). In other words were they lucky or unlucky?

[alexfish]

Interesting question Bandit.

Of course the distances and timespan are immense, but you don't want to be anywhere near a supernova when it blows. So I would think it would depend on the putative life form's distance from the nearest (presumably) blue giant created in the stellar formation period caused by the two galaxies colliding that went supernova. Also to a certain extent their geometry in relationship to the supernova. Not good if a supernova's polar jet is pointed at you.

Both of those would depend on where they were in their galactic habibility zone (http://en.wikipedia.org/wiki/Habitable_zone#Galactic_habitable_zone), which is a refinement you can add to the basic Drake equation (http://en.wikipedia.org/wiki/Drake_equation). In other words were they lucky or unlucky?

You can only apply that to organic , as in relation to the life forms as we know it

Almost all organisms use carbohydrates as sources of energy. In addition, some carbohydrates serve as structural materials. Carbohydrates are molecules composed of carbon, hydrogen, and oxygen; the ratio of hydrogen atoms to oxygen atoms is 2:1.

Who is to say the element table is complete , think also this needs to be looked at , are there theories or formulae for it

[Paqman]

I wonder if any life forms in those glaxies survived? That must have lasted a long time.

Galaxies are mostly open space, so actual collisions (or even near misses) of stars or planets would be extremely rare. I believe our galaxy is supposed to have gobbled up a few smaller ones in the past, and we're going to collide with Andromeda in the future.

[neu5eeCh]

Galaxies are mostly open space, so actual collisions (or even near misses) of stars or planets would be extremely rare. I believe our galaxy is supposed to have gobbled up a few smaller ones in the past, and we're going to collide with Andromeda in the future.

And by the time Andromeda "passes through" the Milky Way (it's possible that not a single star will collide), life on earth will be long gone, our sun will either be a red giant or a white dwarf.