Higher dimensions and my scepticism.

[Daniel Foreman]

Sorry that was a tad emotional.

 

But, blackholes don't exist outside theoretical mathematics, it's incredibly rare for mathematics to predict anything in reality. Typically, we see, observe, then study and understand. It's not impossible to predict something no one has seen, but until we see it it's a theory only. When people start talking about them as if they are a well studied and observed reality I do start to lose my patience.

[Essay]

When people start talking about them as if they are a well studied and observed reality....

 

Are you talking about the observations on the black hole at the center of our own galaxy? ...Because those studies & observations are not based on gamma ray bursts or, I think, those other things you mentioned as "evidence" for black holes.

 

~?

[MigL]

Dan you need to do some reading and inform yourself. Black holes aren't the result of 'tweaking numbers' in GR. They are the result of the same equations which give us space-time curvature. Oh yeah, you don't believe in that either according to some of your posts in other threads.

Black holes have as much observationa data backing them as atoms or even air. You believe in air, don't you? Yet you can't see it, you can only observe its effects. Well, the same is true for black holes.

 

And funny enough, mathematics predicted the existence of Neptune and Pluto, as well as the neutron and positron ( along with ALL anti-matter ) long before they were observationally detected. And I haven't even mentioned the +/-W and Z bosons of electroweak unification ( predicted in yhe 60s, found in the 80s ) or the Higgs boson, also postulated in the 60s, and possibly now found.

Edited December 19, 2012 by MigL

[StringJunky]

But, blackholes don't exist outside theoretical mathematics, .

 

 

This Hubble Space Telescope image contains three main features.

The outer white area is the core or centre of the galaxy NGC4261.

Inside the core there is a brown spiral-shaped disk. It weighs on hundred thousand times as much as our sun.

Because it is rotating we can measure the radii and speed of its constituents, and hence weigh the object at its centre. This object is about as large as our solar system, but weighs 1,200,000,000 times as much as our sun.

This means that gravity is about one million times as strong as on the sun. Almost certainly this object is a black hole.

http://www.damtp.cam.ac.uk/research/gr/public/bh_obsv.html

 

it's incredibly rare for mathematics to predict anything in reality

 

A couple, without trying:

 

In the 1800s, Urbain Jean Joseph Le Verrier used mathematical equations to calculate the existence of Neptune. He gave his calculations to astronomer Johann Gottried Galle at the Berlin Observatory. Using Le Verrier's calculations, Galle was able to observe the planet within one hour of starting. Le Verrier expected to be declared the sole discoverer of Neptune, but months prior to his calculations being completed John Couch Adams, an English mathematician, had accomplished the same feat. As a consequence, Le Verrier and Adams share the honor as Neptune's discoverers.

http://space.about.com/od/astronomydictionary/g/mathastronomy.htm

 

 

May 4, 2011: Einstein was right again. There is a space-time vortex around Earth, and its shape precisely matches the predictions of Einstein's theory of gravity.

Researchers confirmed these points at a press conference today at NASA headquarters where they announced the long-awaited results of Gravity Probe B (GP-B).

"The space-time around Earth appears to be distorted just as general relativity predicts," says Stanford University physicist Francis Everitt, principal investigator of the Gravity Probe B mission.

http://science.nasa.gov/science-news/science-at-nasa/2011/04may_epic/

The whole point about a Theory, of which the it's language is mathematics, is to describe and make predictions. If the mathematics didn't make predictions that actually reflect reality, science would be useless.

Note; A 'Theory' is the the highest and most trusted standard in science, with much observational and experimental confirmation behind it.

 

 

[J.C.MacSwell]

Dan you need to do some reading and inform yourself. Black holes aren't the result of 'tweaking numbers' in GR. They are the result of the same equations which give us space-time curvature. Oh yeah, you don't believe in that either according to some of your posts in other threads.

Black holes have as much observationa data backing them as atoms or even air. You believe in air, don't you? Yet you can't see it, you can only observe its effects. Well, the same is true for black holes.

 

And funny enough, mathematics predicted the existence of Neptune and Pluto, as well as the neutron and positron ( along with ALL anti-matter ) long before they were observationally detected. And I haven't even mentioned the +/-W and Z bosons of electroweak unification ( predicted in yhe 60s, found in the 80s ) or the Higgs boson, also postulated in the 60s, and possibly now found.

I hope you are kidding.

[ACG52]

I hope you are kidding.

 

 

Why? He's correct.

[J.C.MacSwell]

 

 

Why? He's correct.

...and those are pretty nice threads the Emperor is wearing

[ACG52]

...and those are pretty nice threads the Emperor is wearing

 

This is generally the kind of reply you get when there is no reply.

[J.C.MacSwell]

 

This is generally the kind of reply you get when there is no reply.

You seriously believe that there is as much observational evidence for black holes as there is for air?

[ACG52]

_{What's your objective observational evidence for air?}

[J.C.MacSwell]

_{What's your objective observational evidence for air?}

Where do I start? Let me take a breath...

...oh wait I'm done!

 

Seriously, why the need to exaggerate the amount of observational evidence for black holes? It certainly does not make the case for them any more compelling.

Edited December 20, 2012 by J.C.MacSwell

[ACG52]

I said objective observational evidence.

 

Show me a photograph of air.

 

Show me a photograph of an oxygen molecule.

 

Show me a photograph of an atom.

 

I'll show you, (in fact, it was just earlier in this thread) a photograph of a black hole.

[StringJunky]

I'll show you, (in fact, it was just earlier in this thread) a photograph of a black hole.

 

Here's another from the same link (Cambridge University UK):

 

 

Larger image: http://www.damtp.cam.ac.uk/research/gr/public/images/HSTm87.gif

 

M87 is an active galaxy, one in which we see interesting objects. Near its core (or centre) there is a spiral-shpaed disc of hot gas. The first picture places it in context. The second superposes spectra from opposite sides. This allows us to determine the speed of rotation of the disk and its size. From this we can weigh the size of the invisible object at the centre.

Although the object is no bigger than our solar system it weighs three billion times as much as the sun. This means that gravity is so strong that light cannot escape. We have a black hole.

In the first figure, there is a diagonal line. This is believed to be the passage out of those fortunate particles which escape along the axis of rotation and avoid being swallowed by the black hole.

Edited December 20, 2012 by StringJunky

[J.C.MacSwell]

I said objective observational evidence.

 

Show me a photograph of air.

 

Show me a photograph of an oxygen molecule.

 

Show me a photograph of an atom.

 

I'll show you, (in fact, it was just earlier in this thread) a photograph of a black hole.

OK, so you are thinking that observing can only be visual, is that it? Even if you limited it to that (not correct), there are billions of times (please excuse the understatement) more visual evidence of air than black holes.

Edited December 20, 2012 by J.C.MacSwell

[ACG52]

Oh, I'll take observations from any part of the electromagnetic spectrum, not just the visual.

 

Please show me air.

[ajb]

Being cautious, there are observations that can currently only be explained by black holes. As general relativity stands up to all the tests we have asked of it, it is logical to take the existence of black holes seriously.

 

Historically, many people, including Einstein doubted the existence of black holes. The reason being they seemed to require a lot of symmetry and nature would never be so obliging. However, various singularity theorems were constructed that weaken the symmetry requirement. The most general of which are the Hawking-Penrose singularity theorems [1].

 

In essence the Hawking-Penrose singularity theorems are of course technical, but what they say is under some reasonable assumptions, singularities cannot be avoided in general relativity. Basically, singularities and black holes are a rather generic feature of classical general relativity.

 

Reference

[1] S. W. Hawking and R. Penrose, The Singularities of Gravitational Collapse and Cosmology, Proc. R. Soc. Lond. A, 27 January 1970 vol. 314 no. 1519 529-548.

[imatfaal]

!

Moderator Note

 

ACG & JCMac

 

Let's not continue to derail this thread with a pretty meaningless argument.

 

Thanks

 

[Daniel Foreman]

Almost certainly this object is a black hole.

I note that the writer of the article at http://www.damtp.cam.ac.uk/research/gr/public/bh_obsv.html did not say that it was definitely a black hole. I suspect that we're simply discovered something quite interesting and then slapped the black hole label on it for lack of anything better to call it.

 

Perhaps the term core mass would be a better one for now? After all in that article both subject matters are at the centre of their own galaxies. It's not surprising to me that the heaviest, most dense object is at the centre of the galaxy, we see that naturally within our own solar system. The sun is in the middle and everything else has naturally fallen into an orbit.

 

If we zoom out on our own galaxy, (correct me if I'm wrong here) doesn't every star and solar system in that galaxy also orbit the centre like a giant pin wheel? Do we not see this in other galaxies? Circling around and around a larger core be it larger from multiple particles, or a single larger mass, seems to be a repeating theme down to a certain level. Once you get into particle physics I believe this behaviour starts to change quite dramatically, though I'm still learning about that myself.

 

So yes, I can accept that the core of our own galaxy and others are super dense. But does that mean it's so dense that light can not escape? Also what is it's actual size in proportion to it's down density? How do we actually test for these things from so far away, and with such limited information? If so, is this actual evidence for higher dimensions for extra curves in space which was the original subject matter of this thread?

 

This is one of the reasons I dislike blackholes so much is that many people seem to want them to exist, or assume they exist. I think that is a very dangerous trend in science.

 

At the end of the day I can only judge what is likely based on my own experiences, what I know myself, I fully admit I am no professor, and certainly not an expert. My understanding of the mathematics behind most of the subjects I'm discussing today is certainly beyond my understanding I freely admit that. I am reading what everyone says I promise even if I do sound incredulous, and I am taking on board what everyone says. I suppose my biggest issue with most of this is the inaccessibility of it all.

 

For example, I know ohms law works because I've applied it on many occasions, I can see that it works reliably every time. When I want to work out the distance between two points in space, I know trigonometry works because I use it all the time when programming. From that programming I can also simulate various aspects of physics, such as the impact of mass, how to calculate the bounce of a ball. These are all things that are extremely accessible. I also know that if I adjust the numbers for these sums beyond certain ranges these sums can create some very weird stuff that simply would never ever occur in nature, so I have to place limiters on these things in a very artificial way. The limiters of the sum are not built in naturally and have to be added with additional insertions of logic.

 

It's these experiences that make me more sceptical of these things. I simply can't physically play with higher dimensions, and I can't relate them to my 3D world. Many people assume that time is a dimension in of itself, but time dilation kinda disproves that for me, after all why would one part of the dimension proceed at a lesser rate then another? Then people start talking about space time, and curved space time. Something I've certainly never seen nor been able to play with.

 

So I simplify things. I know motion exists, I know that time is based on the motion of pendulums, I know that at very least we represent waves of radiation with the movement of a sin wave, or signal at least giving the idea of movement within it's internal mechanisms. I know that atoms energy states and internal motions are a factor even if the idea of motion here becomes a little bit wonky. I know from the double slit experiment that various sized particle firings create some fascinating interference fields, suggesting an influence exerted by the particle that appears to extend beyond it's own physical dimensions. So I can accept the presence of forces. These are all things that have been demonstrated to me.

 

So I hope the world of practical science really does one day discover black holes, but to be honest I'm probably unlikely to be convinced by them until I fly up to one and transmit my final words as "opps, they were right" to this forum via galatica-com

[StringJunky]

Being cautious, there are observations that can currently only be explained by black holes. As general relativity stands up to all the tests we have asked of it, it is logical to take the existence of black holes seriously.

 

Historically, many people, including Einstein doubted the existence of black holes. The reason being they seemed to require a lot of symmetry and nature would never be so obliging. However, various singularity theorems were constructed that weaken the symmetry requirement. The most general of which are the Hawking-Penrose singularity theorems [1].

 

In essence the Hawking-Penrose singularity theorems are of course technical, but what they say is under some reasonable assumptions, singularities cannot be avoided in general relativity. Basically, singularities and black holes are a rather generic feature of classical general relativity.

 

Reference

[1] S. W. Hawking and R. Penrose, The Singularities of Gravitational Collapse and Cosmology, Proc. R. Soc. Lond. A, 27 January 1970 vol. 314 no. 1519 529-548.

 

Can't GR's singularities be correct for black holes but incorrect for the big bang (or just before it) because this is where the problems I've seen aired seem to lie? Intuitively, I don't have a problem with this because the big bang is a another scenario to which it does not apply or at least extends beyond GR further back in the universe's creation...what I'm saying is that perhaps GR is only relevant after gravity (spacetime) is created in the BB ie prior to a certain point in time, the density was such that it had no geometry because everything was physically connected.

 

 

 

I note that the writer of the article at http://www.damtp.cam...ic/bh_obsv.html did not say that it was definitely a black hole. I suspect that we're simply discovered something quite interesting and then slapped the black hole label on it for lack of anything better to call it.

 

Daniel, scientists never talk with absolute certainty. They always leave room for error. They are a cautious lot.

Edited December 20, 2012 by StringJunky

[elfmotat]

I note that the writer of the article at http://www.damtp.cam.ac.uk/research/gr/public/bh_obsv.html did not say that it was definitely a black hole. I suspect that we're simply discovered something quite interesting and then slapped the black hole label on it for lack of anything better to call it.

 

No. They called it a black hole because a black hole is the only known object that could be so small and yet that massive.

 

 

Perhaps the term core mass would be a better one for now? After all in that article both subject matters are at the centre of their own galaxies. It's not surprising to me that the heaviest, most dense object is at the centre of the galaxy, we see that naturally within our own solar system. The sun is in the middle and everything else has naturally fallen into an orbit.

 

Anything that dense has to be a black hole. Buchdahl's theorem proves that for a stable, uncollapsed spherical object of mass M and radius R, [math]GM/c^2R \leq 4/9[/math].

 

What this means is that if you were to construct a star of radius [math]R=9GM/4c^2[/math] and you gave it a little inward push, it would have no choice but to collapse into a black hole. Resisting collapse would require infinite internal pressure.

 

 

So yes, I can accept that the core of our own galaxy and others are super dense. But does that mean it's so dense that light can not escape?

 

Yes, as I just explained.

 

 

Also what is it's actual size in proportion to it's down density?

 

It depends on what you mean by "density." It's more customary to compare the mass and the radius. A black hole of mass M has a radius [math]R=2GM/c^2[/math].

 

 

How do we actually test for these things from so far away, and with such limited information?

 

What do you mean by "limited information?" We know a great deal about the centers of galaxies. We can determine the central black hole's mass from the way nearby stars orbit it.

 

 

If so, is this actual evidence for higher dimensions for extra curves in space which was the original subject matter of this thread?

 

No.

 

 

This is one of the reasons I dislike blackholes so much is that many people seem to want them to exist, or assume they exist. I think that is a very dangerous trend in science.

 

People assume they exist because they do exist! If you think otherwise then you're going to have to explain away mountains of observational evidence. Scientists don't "want" anything but the truth. You're the one who seems to be letting bias get in the way of understanding how nature works.

 

 

I suppose my biggest issue with most of this is the inaccessibility of it all.

 

You're on the internet. How could you possibly claim that any information is inaccessible?

 

 

For example, I know ohms law works because I've applied it on many occasions, I can see that it works reliably every time. When I want to work out the distance between two points in space, I know trigonometry works because I use it all the time when programming. From that programming I can also simulate various aspects of physics, such as the impact of mass, how to calculate the bounce of a ball. These are all things that are extremely accessible.

 

These are called "experiments." We humans have also conducted many experiments and compiled tons of observational evidence that General Relativity is a reliable theory as well. You might not have been personally involved with the experiments, but you can easily find the details and data online.

 

 

I also know that if I adjust the numbers for these sums beyond certain ranges these sums can create some very weird stuff that simply would never ever occur in nature, so I have to place limiters on these things in a very artificial way. The limiters of the sum are not built in naturally and have to be added with additional insertions of logic.

 

 

I really don't know what you mean by this. An example would help.

 

 

It's these experiences that make me more sceptical of these things. I simply can't physically play with higher dimensions, and I can't relate them to my 3D world. Many people assume that time is a dimension in of itself, but time dilation kinda disproves that for me, after all why would one part of the dimension proceed at a lesser rate then another? Then people start talking about space time, and curved space time. Something I've certainly never seen nor been able to play with.

 

That's called being closed-minded. Around 240 BC Eratosthenes knew the Earth must be round, and he even estimated its circumference which he calculated using shadows from the Sun at various locations (Greece and Egypt). He was correct to a good margin of error. Where would we be if we only accepted the evidence directly in front of our eyes? We'd probably still think the Earth was flat.

 

So I hope the world of practical science really does one day discover black holes, but to be honest I'm probably unlikely to be convinced by them until I fly up to one and transmit my final words as "opps, they were right" to this forum via galatica-com

 

The world of "practical science" already has discovered black holes. The evidence is free and readily available to you. You don't accept it because you have some strange bias against them.

[abisha]

I have my own vision about how extra dimensions will look like, Here i try explaining.

 

Picture 1,

rather awkward we just see the galaxy like we all know, yea i am a crapy artist.

but something is weird, and can't be explained that dark black dot.

anyone knows what it is, yet their is not a single person alive that can really explain what it is.

 

that blackhole is related to so called big bang,their is no way around it we are born out of singularity but who say's we ever left it?

we may be trapped inside a Blackhole in a Another Universe where other laws and new or modified physics, like 2

 

so why do i think something so strange like this.

their is a lot of matter, and their is no really a logic to big bang

Sure laws where made after the bigbang but that's just theory

if a singularity was born outside this universe, a bigbang makes much more sense and explain where new matter comes from, if where all eliminated by dark matter.

[swansont]

I note that the writer of the article at http://www.damtp.cam.ac.uk/research/gr/public/bh_obsv.html did not say that it was definitely a black hole. I suspect that we're simply discovered something quite interesting and then slapped the black hole label on it for lack of anything better to call it.

 

No, s/he says "Almost certainly this object is a black hole." and "We have a black hole." The gap between those statements and "slapped the black hole label on it for lack of anything better to call it" is pretty big.

[Daniel Foreman]

Daniel, scientists never talk with absolute certainty. They always leave room for error. They are a cautious lot.

Oh I dunno, I'm sure if they wanted to prove that an orange existed, they'd just hand me an orange. The point is they are cautious because they are not absolutely certain.

 

 

 

Anything that dense has to be a black hole.

No ti doesn't, that's like saying anything that burns has to be a star. A match burns, but that's not a star. You might say yes, there is a big difference between a sun, and a match. But then, until we see a true black hole, and test what's at the centre of our galaxy there might be as much difference between them as both a match and a star.

 

 

 

Yes, as I just explained.

We've not seen light become unable to escape it, we're making extremely long distence observations and assuming it can't. There's a difference, espically as we've ever actually directly observed anything that can suck in light, it's just a theory. That theory has to be tested in real world situations before it becomes fact, Yet you state with total certainty that light can not escape, when in reality you only speak from theory.

 

 

What do you mean by "limited information?" We know a great deal about the centers of galaxies. We can determine the central black hole's mass from the way nearby stars orbit it.

Naw we don't, and it's pure arrogance to think that we do (in my opinion). It's like saying I know everything about a species of beatle I observed while sitting on a mountain with a powerful telescope. I might see it's outsides, it's shell, view the light bouncing off it with differing hues, but I'd know nothing about the internal mechanisams of that beatle. For that I need to get up close, and start taking it apart ( p.s. I do not condone beetle murder, use a cat scanner instead! )

 

I mean imagine if an alien was looking at earth, it sees a car, what would they think about this car? What if they had no preconception of vehicular design or combustion technology. Might they conclude that cars are domestic beasts people get inside of, and get out of at will?

 

As they say,don't judge a book by it's cover. Or in this case a super dense formation of matter rotating at the core of our galaxy, it might not be what any of use expect.

 

 

 

You're on the internet. How could you possibly claim that any information is inaccessible?

 

I'm sorry I wasn't clear. I can read about harry potter online, or god if I want. But I can't experiement with god, I can't touch god, I can't observe god directly. So if someone presented you with "the mathematics of god" without a god to test it against, how do you demonstrate that it's real. in what way is it accessible. This is the difference between theory, mathematics and real world situations.

 

I can take a radio apart, understand how a radio works. I can't take apart higher dimensions or observe higher dimension. I can make no use of higher dimensions. So how can I or anyone else definitively say there are any?

 

 

 

These are called "experiments." We humans have also conducted many experiments and compiled tons of observational evidence that General Relativity is a reliable theory as well. You might not have been personally involved with the experiments, but you can easily find the details and data online.

Yes the government won't give me any uranium to play with.

 

Here's an interesting article on the web entitled "Problems with General Relativity"

 

1. The red shift.

2. Matter and energy not equivalent

3. Problem with the metric model

4. Cosmological issues

5. General Relativity is dimensionally incomplete

6. General relativity is mathematically incomplete

7. Complexity.

 

http://cosmoquest.org/forum/showthread.php/15196-Problems-with-General-Relativity

 

So it's certainly not perfect by any stretch of the imagination. This is what I mean by observations not matching the theory.

 

 

 

I really don't know what you mean by this. An example would help.

I'll see if I can dig out one of my old C++ examples, I experimented with various physics examples using a simulator and found that a specific range of numbers caused some very strange reactions. give me a couple of days I don't know where I put my backups.

 

 

 

That's called being closed-minded. Around 240 BC Eratosthenes knew the Earth must be round, and he even estimated its circumference which he calculated using shadows from the Sun at various locations (Greece and Egypt). He was correct to a good margin of error. Where would we be if we only accepted the evidence directly in front of our eyes? We'd probably still think the Earth was flat.

Absolutely it's close minded. I freely admit that. On the other hand if someone tells me that they saw a pink unicorn eating moonrocks last night as they observed the moon, then it started fighting moon dragons and flying moon pigs started invading earth with greeting cards. Well, I'd dismiss them out of hand, and that would be a very closed minded thing to do as well.

 

When I say I don't believe in god, I'm told all the time that I'm so closed minded. Same when people claim to see ghosts. Or that the human soul exists.

 

There's no end to the crap you'd have to believe if you were truly and completely open minded.

 

Balance in all things, open mindedness is all very well, but sometimes you need to judge things against your own experience and knowledge.

 

 

 

The world of "practical science" already has discovered black holes. The evidence is free and readily available to you. You don't accept it because you have some strange bias against them.

Please, post the links. I'm happy to look at anything!

 

 

 

No, s/he says "Almost certainly this object is a black hole." and "We have a black hole." The gap between those statements and "slapped the black hole label on it for lack of anything better to call it" is pretty big.

The term black hole was used, so that's what she called it. There was clearly no other definition or word she could compare it too.

[Delta1212]

Oh I dunno, I'm sure if they wanted to prove that an orange existed, they'd just hand me an orange. The point is they are cautious because they are not absolutely certain.

Absolute certainty is a good quality to have if you want to be wrong.

[Daniel Foreman]

I'm absolutely certain that I exist, I think therefore I am. You can't build castles in the sky if you don't have your boots firmly on rock.