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Study: Our 3D Universe Could Have Originated From a 4D Black Hole

Soulskill posted 1 year,17 days | from the useless-physics-trivia dept.

Science 337

New submitter TaleSlinger sends this quote from Nature: "Afshordi's team realized that if the bulk universe contained its own four-dimensional (4D) stars, some of them could collapse, forming 4D black holes in the same way that massive stars in our Universe do: they explode as supernovae, violently ejecting their outer layers, while their inner layers collapse into a black hole. In our Universe, a black hole is bounded by a spherical surface called an event horizon. Whereas in ordinary three-dimensional space it takes a two-dimensional object (a surface) to create a boundary inside a black hole, in the bulk universe the event horizon of a 4D black hole would be a 3D object — a shape called a hypersphere. When Afshordi's team modeled the death of a 4D star, they found that the ejected material would form a 3D brane surrounding that 3D event horizon, and slowly expand. The authors postulate that the 3D universe we live in might be just such a brane — and that we detect the brane's growth as cosmic expansion. 'Astronomers measured that expansion and extrapolated back that the Universe must have begun with a Big Bang — but that is just a mirage,' says Afshordi."

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337 comments

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Sorry (5, Funny)

krovisser (1056294) | 1 year,17 days | (#44852633)

Turtles all the way down.

Re:Sorry (1, Funny)

binarylarry (1338699) | 1 year,17 days | (#44852659)

My brane asplode.

Re:Sorry (3, Funny)

NoNonAlphaCharsHere (2201864) | 1 year,17 days | (#44852665)

Mmmmmmm. Branes.

Re:Sorry (-1, Offtopic)

Anonymous Coward | 1 year,17 days | (#44852729)

I like turtles.

Re:Sorry (-1, Offtopic)

davester666 (731373) | 1 year,16 days | (#44852833)

I like turtle soup.

Re:Sorry (-1, Offtopic)

tmosley (996283) | 1 year,16 days | (#44853255)

Shredder?

Re:Sorry (-1, Offtopic)

JustOK (667959) | 1 year,16 days | (#44853083)

Happy together with the turtles

Re:Sorry (-1, Redundant)

oheso (898435) | 1 year,17 days | (#44852737)

You beat me to it.

Re:Sorry (0, Offtopic)

ClaraBow (212734) | 1 year,16 days | (#44852793)

4D chocolate covered turtles!

Re:Sorry (-1)

Anonymous Coward | 1 year,16 days | (#44853251)

Or alternativeley, hot grits.

Re:Sorry (5, Insightful)

FredGauss (3087275) | 1 year,16 days | (#44853307)

Turtles all the way down.

Funny, but also Insightful? Turtles all the way down, or turtles all the way up? If we inhabit the 3D manifold that resides in a black hole within a 4D bulk universe, and observe 3D black holes (with a 2D event horizon), does this imply 1D black holes inside of the black holes that we observe (with 0D black holes inside...). Is the 4D bulk universe a black hole in a 5D hyper-bulk universe within a 6D ... Is there a physicist in the house that can shed more light on this than the article/paper?

NO! (2, Funny)

TechyImmigrant (175943) | 1 year,17 days | (#44852663)

His noodliness wishes to inform you that string theory is closer to the truth but the full truth is that the universe is made of strings of spaghetti.

Re:NO! (4, Funny)

VortexCortex (1117377) | 1 year,17 days | (#44852697)

Falling into a black hole you are stretched like strands of spaghetti.
The tendrils of a sun's magnetic fields are like great bands of spaghetti as well.

However, this is merely confirmation bias. Clearly, with all the roundness everywhere His meaty balls have the most influence.

Re:NO! (2)

TechyImmigrant (175943) | 1 year,16 days | (#44852795)

And divine sauce.

Re:NO! (1)

Anonymous Coward | 1 year,16 days | (#44853171)

Every single of those current 3D black holes will provide the pasta source for his noodliness 2D universes. Then those 2D universes will create 1D black strings which will cause even his noodliness to blush.

Sounds good to me... (1)

mspohr (589790) | 1 year,17 days | (#44852685)

... but what do I know?
I personally like the turtles explanation better than spaghetti but I'm just along for the ride.

Get out the bong (2, Insightful)

wes33 (698200) | 1 year,17 days | (#44852687)

seriously, it's time

Re:Get out the bong (0)

Anonymous Coward | 1 year,17 days | (#44852741)

Yeah, man...no kidding.

Now I have Insane Clown Posse playing on a loop inside my head:

"Insane in the membrane, insane in the brane."

Oh well, I might as well go with it! *rolls blunt*

Re:Get out the bong (5, Informative)

binarylarry (1338699) | 1 year,16 days | (#44852771)

That would be Cypress Hill, not ICP.

Re:Get out the bong (1)

myowntrueself (607117) | 1 year,16 days | (#44852817)

That would be Cypress Hill, not ICP.

though 'Riddlebox' is also appropriate.

Re:Get out the bong (5, Insightful)

gl4ss (559668) | 1 year,16 days | (#44852905)

ICP could be playing CH, it's his head, his rules.

but if the clown posse is playing cypress hill songs in his head he might not need another hit for a while...

Re:Get out the bong (2)

zm (257549) | 1 year,16 days | (#44852993)

I think they did.

Re:Get out the bong (-1)

Anonymous Coward | 1 year,16 days | (#44853223)

I think they did.

Newton was baked off his ass when that apple hit his head. Einstein was stoned to the bone when he came up with his theory of relativity. What would be more shocking to you, the theory, or the way it was born? Does it really fucking matter? We're here, smarter as a whole for it.

And the "stoner" will laugh their ass off when proven right.

Re:Get out the bong (0)

Anonymous Coward | 1 year,16 days | (#44853057)

seriously, it's time

Isn't it ironic you want to call these "stoner" theories while we sit back and idolize those who merely wanted to prove the world was round. Sad to say thousands of years later, coupled with space travel, we still have people today who don't believe it, and makes you really wonder who is stupidly high here. The theorist, or the ones they're trying to convince.

Keep in mind that plenty of theories have been birthed under the influence of various drugs all throughout history, so might want to hold off on the smart-ass comments for now. You could be viewed no better than a member of the Flat Earth Society if the theory here is ever proven or accepted. And quite honestly, it doesn't sound any more far-fetched than the big bang.

Hell, if you want to know who's really hitting the bong hard, walk into a church. They have some theories for you...

lol (0)

Anonymous Coward | 1 year,17 days | (#44852691)

Could've, didn't.

Uhhh... what did he just say to us? (5, Funny)

pspahn (1175617) | 1 year,17 days | (#44852711)

So whatever a 4D star is, when it explodes there is a 3D layer that represents the event horizon. We live in this layer. One side of the layer is a 4D black hole, and the other side of the layer is some other kind of nothingness. Yeah?

Is there someone here I can offer monetary compensation to for them to comprehend this summary for me?

Re:Uhhh... what did he just say to us? (5, Interesting)

rasmusbr (2186518) | 1 year,17 days | (#44852755)

If I understood it correctly they mean that on the other side is a universe with 4 spatial dimensions.

Think of it this way: in a universe with 3 spatial dimensions a black hole has a 2-d surface (shaped roughly like the surface of a sphere) as its event horizon. On the inside of the surface is the black hole. On the outside is the rest of the universe. Generalizing this to a hypothetical universe with 4 spatial dimension, a black hole in such a universe would have a 3-d "surface" surrounding it with the black hole inside of the surface and the rest of the universe outside of it.

By the way, there is already an idea floating around about how the edge of the visible universe seems be a bit like the event horizon of a black hole. Once something has passed the edge of the visible universe it is effectively lost to us, a bit like when something passes the event horizon of a black hole.

Re:Uhhh... what did he just say to us? (1, Interesting)

Anonymous Coward | 1 year,16 days | (#44852829)

Technically there's nothing _inside_ the black hole. All the matter is on the surface. The circumference of a black hole is a function of the maximum amount of matter you can pack onto a two-dimensional sphere. A black hole *is* two-dimensional, it just appears three-dimensional from our perspective. Although that's pretty much what you said, minus semantics.

I'm not a physicist, but I think that's really cool. I suppose that phenomena could be a mere coincidence, but lots of people operate on the assumption that it's not coincidental. This phenomena is especially notable because it's observable and testable, unlike all the theories about 4th, 5th, etc dimensions, which work out on paper but aren't yet readily discernible (i.e. distinguishable) in actuality.

Re:Uhhh... what did he just say to us? (4, Interesting)

rasmusbr (2186518) | 1 year,16 days | (#44853283)

Well, I'm not a physicist either and I could be wrong but I think that there are two equivalent views of what a black hole is. The holographic view is pretty strange...

The stuff that supposedly sits at the event horizon in the holographic view is not matter; it is information. My understanding is that the event horizon of a black hole can basically be though of as a data storage device that stores scrambled information about everything that the hole has swallowed, except for the information about the stuff that it has since spit out.

I imagine it works something like this: when the black hole swallows some matter the information content in that matter (that is the entropy) gets stored on the horizon and the horizon expands to make room for it. When the hole spits out a particle the horizon "erases" the information/entropy of that particle and the horizon contracts to make sure there isn't any empty "disk space".

Re:Uhhh... what did he just say to us? (2)

tmosley (996283) | 1 year,16 days | (#44853285)

There is matter inside a black hole. You are thinking of the optical illusion that makes it seem like matter falling into a black hole slows down. From the falling matter's point of view, there is no time dilation, it just falls right through the event horizon like there was nothing there.

I THINK that is the way it went.

Re:Uhhh... what did he just say to us? (1)

Anonymous Coward | 1 year,16 days | (#44853305)

Sorry, but I'm going to have to call bullshit in this.

What you're describing is one of the "what it looks like to an outside observer" brain-farts (vs. "what actually happens") that confuses the hell out of everyone who thinks they understand how relativity works, because they forget that what we observe is just a projection of what's really happening.

Re:Uhhh... what did he just say to us? (1)

binarylarry (1338699) | 1 year,16 days | (#44853367)

A two dimensional sphere?

That's like a square from the 8th dimension!

Re:Uhhh... what did he just say to us? (5, Interesting)

Rockoon (1252108) | 1 year,16 days | (#44852849)

What will really cook your noodle is if you calculate the mass of a black hole whos event horizon the size of the visible universe, its within an order of magnitude of the suspected mass of the visible universe (including dark matter.)

A common misconception is that black holes require singularities. Simple thought experiments show it differently.. for example, imagine living in a universe with a mass about that of a black hole that would have an event horizon that is just a little bit smaller than the universe. Now imagine that universe contracting. You can see that as it contracts it will eventually become small enough to form an event horizon without a singularity.

Re:Uhhh... what did he just say to us? (0)

Anonymous Coward | 1 year,16 days | (#44853107)

I thought the definition of an event horizon was the point where not even light can escape. Your definition does not match that, what you are arguing is a colapsing universe vs an ever expanding one. An event horizon does require a singularity because that is the only thing with enough density to suck in light.

Re:Uhhh... what did he just say to us? (0)

Anonymous Coward | 1 year,16 days | (#44852853)

So... our expanding universe would propagate 'around' the event horizon of the 4-d black hole until it starts running into itself?

Re:Uhhh... what did he just say to us? (1)

tmosley (996283) | 1 year,16 days | (#44853293)

It doesn't run into itself, it gets bigger. A balloon doesn't run into itself as it inflates.

Re:Uhhh... what did he just say to us? (5, Interesting)

mysidia (191772) | 1 year,16 days | (#44853015)

By the way, there is already an idea floating around about how the edge of the visible universe seems be a bit like the event horizon of a black hole. Once something has passed the edge of the visible universe it is effectively lost to us

Because we can only see things that have sent light back towards us, AND that return light has already reached us. If something is further away from earth, than the distance that light could have possibly travelled back from the object towards earth from the time that the object was at that distance, then by induction: we cannot see the object yet.

Because near the rim of the universe.... the universe is expanding faster than the speed of light; so it's far enough, that light would take longer to travel back to where earth is, than the duration the universe has existed.

Furthemore: since the universe can continue to expand at a rate faster than the speed of light --- the light travelling back towards earth, can never overtake the rate of the universe's expansion, and find its way back to us.

It is kind of like an infinite treadmkill ---- very similar to the concept of a gravitational well that is so deep not even light can escape.

We have an outer rim of our universe expanding so quickly, that not even the very timespace; the spatial dimensions or the passage of time can escape it.

Re:Uhhh... what did he just say to us? (1)

Kjella (173770) | 1 year,16 days | (#44853235)

Because near the rim of the universe.... the universe is expanding faster than the speed of light; so it's far enough, that light would take longer to travel back to where earth is, than the duration the universe has existed. Furthemore: since the universe can continue to expand at a rate faster than the speed of light --- the light travelling back towards earth, can never overtake the rate of the universe's expansion, and find its way back to us.

I don't really see why you have to bring FTL into it. If the universe is 13.8 billion years old and we're in the middle of it (close enough approximation) we'll only see events up to 6.9 billion years away. Sure, in another 6.9 billion years we'll be able to observe the entire current universe but by then it'll have expanded another 6.9 billion light years. It has a head start on us and our "observable universe" will never catch up to the real universe, because our ability to observe expands at the same rate as its natural expansion.

Re:Uhhh... what did he just say to us? (5, Informative)

ChromaticDragon (1034458) | 1 year,16 days | (#44853351)

Umm... No.

http://en.wikipedia.org/wiki/Observable_universe [wikipedia.org]

http://en.wikipedia.org/wiki/Future_of_an_expanding_universe [wikipedia.org]

http://en.wikipedia.org/wiki/Big_Rip [wikipedia.org]

We have no idea how large the universe is. But the current estimates of the radius of the observable universe is about 45 billion light years. That's how "far" we can see. And this is indeed due to the expansion of the universe essentially moving distances apart faster than light can travel. Furthermore, it's not just that we won't "catch up"... It seems rather likely that it's gonna get worse over time - to the point we won't be able to see much at all (relatively speaking).

Re:Uhhh... what did he just say to us? (1)

mrbester (200927) | 1 year,16 days | (#44853321)

Couldn't that be thought of as evaporation?

Re:Uhhh... what did he just say to us? (2)

RedHackTea (2779623) | 1 year,16 days | (#44853115)

So if a 2d star were to explode, there will be 1d surface? So you're telling me that flatland [wikipedia.org] could exist?

Re:Uhhh... what did he just say to us? (0)

Anonymous Coward | 1 year,16 days | (#44852935)

And where did the 4D universe come from?
Why a 5D black hole of course. And that one came from a 6D universe and so on and so forth.

Re:Uhhh... what did he just say to us? (4, Funny)

plover (150551) | 1 year,16 days | (#44852987)

Damn! Just when 3D printers started getting reasonably priced, now I have to go out and buy a 4D printer? And to print a 4D universe you're telling me I'll need a 5D printer?

Theoretically, would a 4D printer use "strings" instead of "filament"?

Re:Uhhh... what did he just say to us? (1)

tmosley (996283) | 1 year,16 days | (#44853311)

When you get a 4D printer, make one of the dimensions timelike and you print an infinite-D printer before you were even born.

Re:Uhhh... what did he just say to us? (5, Funny)

pspahn (1175617) | 1 year,16 days | (#44852995)

All the way up to 20D, at which point the DM's mother informs him it's time for dinner (corndogs and mac'n'cheese yet again).

Re:Uhhh... what did he just say to us? (1)

Anonymous Coward | 1 year,16 days | (#44853033)

The presented idea is not knew - its also called "Holographic Universe" where incoming material in "randomized" in quantum way and increases the size of the universe - causing not only perceived expansion but also time-like evolution: if the system was isolated with limited total matter/information, it would be "static" with nothing interesting happening. There are theories that such black-hole/holographic universe would have reduced dimension, other state that this is not necessary.

As to your question if we live in the Schwarzschild layer - it does not matter what is a primary reference coordinate system. You can have one coordinate system with its physics, but he same system can be describer after some transform - you can thing about it as for instance as a Fourier-like transform where you would also transform all laws of physics, but essentially still describing the same system. This is also where the name Holographic universe came from; the "3D" universe and its physics would be a wave-like superposition of the status within the "2D' Schwarzschild layer. In this case the reduction of the dimension is not necessary, but one can also define laws as degree-of-freedom reducing factors. Such factors are essentially reduction of dimensionality, so one can speculate that this global dimensionality lose is "The Primary Law" and all laws of physics could be derived from it.

Ps: I am an ex-physicist with passionate hate of string theories (some could say - and rightfully - that I do not understand them) and I love "holographic universe" theories but it might be extremely difficult, maybe even impossible to built useful physics from it...

Don't get too confused (3, Informative)

Anonymous Coward | 1 year,16 days | (#44853061)

The article is about string theory (I think more properly called "M-Theory" these days but not sure). It is the outcome of a lot of very crazy math and complicated equations that are hard to visualize.

But, what this theory sorely lacks is evidence. By which I mean any evidence at all. It is popular in the physics world because it can resolve the discrepancies between quantum mechanics (for which there is quite a lot of solid, verifiable evidence) and general relativity (for which there is also quite a lot of evidence). Everyone wants to be aboard THAT train...so it gets a lot of attention... ...but it still lacks evidence. And without the evidence it is just so much hot air.

So, don't lose any sleep over this one. The proof just isn't there.

Re:Uhhh... what did he just say to us? (1)

GargamelSpaceman (992546) | 1 year,16 days | (#44853159)

I don't think it said that we live in the event horizon. We're the nebula, right? And since it is a 4D nebula, we're only a tiny slice of it.

I love/hate these developments b/c I don't understand them but they're interesting, and why really? Why are they sometimes interesting even though I don't understand them?

Puff puff pass.

Maybe that's it.

Re:Uhhh... what did he just say to us? (1)

hazah (807503) | 1 year,16 days | (#44853229)

No, the surface speculated is the event horizon. There's only so much one can say about a black hole... mass, and spin.

Finally (1)

capt_peachfuzz (1013865) | 1 year,17 days | (#44852721)

An explanation of why my socks go missing and where they went.

Re:Finally (0)

Anonymous Coward | 1 year,16 days | (#44852841)

I solved that problem my first year of college. Stick your damn head inside the dryer, turn the drum, and run your hand alongside the inside of the drum wall. You can do it with one hand or two, but if you're just starting out I suggest two, unless the dryer is low to the ground and you're kneeling.

I haven't lost a sock in 15 years, although now I actually have to throw them away when they get old, rather than let fate take them to the great dryer in the sky.

We live inside a black hole? (1)

manu0601 (2221348) | 1 year,17 days | (#44852759)

If I understand correctly, the universe we see is the inside of a black hole, and the big bang is the time that black hole created its singularity.

Now I can imagine that in each black hole we see there is another universe. Or is it always the same universe that is found inside all different black holes? And I still have trouble to imagine what happens to someone taking a dive into a black hole. Is it possible to enter the universe inside a black hole?

Re:We live inside a black hole? (1)

Azure Flash (2440904) | 1 year,16 days | (#44852821)

Maybe when you enter a 3D black hole you become a very oddly shaped Flatlander.

Re:We live inside a black hole? (1)

manu0601 (2221348) | 1 year,16 days | (#44852971)

As I understood TFA, the universe inside of the blackhole is 3D, just like the universe outside.

Re:We live inside a black hole? (1)

plover (150551) | 1 year,16 days | (#44853005)

During entry into a 3D black hole, I bet you get squished pretty much into a speck indistinguishable from a "point".

Re:We live inside a black hole? (0)

Anonymous Coward | 1 year,16 days | (#44852867)

by corollary, each of our black holes would be a 2-d universe. It seems to me that they are talking about higher dimensions being smashed down into lower dimensions

Re:We live inside a black hole? (0)

Anonymous Coward | 1 year,16 days | (#44852927)

Wrong. The paper says that our universe is the ejecta from a four-dimensional star going supernovae. Part of the star collapses into a black hole, but part is ejected away. We're some kind of structure in the ejecta.

If we were actually part of the black hole, we wouldn't be discussing this. A black hole has maximal entropy. Since the entropy of our observable universe is still increasing, we can't possibly be part of a black hole. Indeed, if we were at maximal entropy we couldn't exist as dynamic, intelligent beings which create localized structure--albeit at the price of hastening global entropy.

Re:We live inside a black hole? (3, Insightful)

mysidia (191772) | 1 year,16 days | (#44853103)

Is it possible to enter the universe inside a black hole?

Arguably... to enter the universe inside a blackhole; you have only to enter the event horizon, and merge with it.

Once you merge with the event horizon; you can never leave the black hole or ever be visible to an outside observer again. Also; you will get squashed into 2 dimensions, and your particles will be scrambled ---- so although the matter that comprises you merges with the universe inside the blackhole: your physical body does not survive.

Physicists cannot say what happens to your immortal soul --- whether it escapes the pull; or whether it too becomes entrapped in the event horizon of that featureless pocket universe for the rest of eternity.

It's not a paper in Nature (4, Informative)

93 Escort Wagon (326346) | 1 year,16 days | (#44852799)

It's a news story on their website talking about a preprint paper posted on Arxiv.

What's their point? (4, Funny)

istartedi (132515) | 1 year,16 days | (#44852807)

What's their point? There's not a singular thing I can see there.

Re:What's their point? (1)

Anonymous Coward | 1 year,16 days | (#44852863)

Well, it is a black hole.

If we fall into a black hole? (0)

Anonymous Coward | 1 year,16 days | (#44852823)

So can we go into the 2-D dimension then?

Jack Chick is going to have fun with this (0)

Anonymous Coward | 1 year,16 days | (#44852831)

Scientists now claim that the universe originated from a gigantic asshole...

Black hole (0)

Anonymous Coward | 1 year,16 days | (#44852839)

So when the Universe is expanding, is that caused by the black hole sucking in matter from this 4D Universe?

And what happens if this black hole evaporates? do we all just go POOF?

Obligatory XKCD (3, Funny)

Anonymous Coward | 1 year,16 days | (#44852843)

"I just had an awesome idea. [xkcd.com] Suppose the entire observable universe exists as a 3d brane on the edge of a 4 dimensional black hole."

"Okay. What would that imply?"

"I dunno."

Wrong in so many ways (1)

dankasak (2393356) | 1 year,16 days | (#44852897)

- We live in a 4-dimensional universe, NOT a 3-dimensional one. Perhaps someone is forgetting time??? - A hypersphere is a 4-dimensional sphere, not a 3-dimensional one. Also the idea that 'space is expanding' is absurd ( and this study perpetuates this idea by claiming they've discovered an explanation for it ). Space is not absolute; it's relative. To say that space is 'expanding' in this context means nothing. The RELATIVE distances of objects to each other may be changing. This is not the same thing as space expanding. Is there something *beyond* the furthest reach of space, that space is now approaching? It's a ridiculous thing to say.

Re:Wrong in so many ways (0)

Anonymous Coward | 1 year,16 days | (#44852931)

we have assigned time as a 4th dimension out of convenience, just like a flatlander would be inclined to assign time as the third dimension without having any knowledge of the third dimension that we experience

That's easy for you to say .. (3, Funny)

codeusirae (3036835) | 1 year,16 days | (#44852899)

".. we happen to live in the causal future of the classical big bang singularity .. we outline a novel mechanism through which any thermal atmosphere for the brane, with comoving temperature of 20% of the 5D Planck mass can induce scale-invariant primordial curvature perturbations on the brane, circumventing the need for a separate process (such as cosmic inflation) to explain current cosmological observations ..."

Vindication! (2)

musth (901919) | 1 year,16 days | (#44852909)

I've been saying just this for years.

I need a car analogy (0)

Anonymous Coward | 1 year,16 days | (#44852915)

Please?

Men in Black was right! (1)

pgregg (185457) | 1 year,16 days | (#44852939)

The galaxy is on Orion's Belt.

I'm having a little trouble with the geometry (1)

Dunbal (464142) | 1 year,16 days | (#44852967)

In our Universe, a black hole is bounded by a spherical surface called an event horizon. Whereas in ordinary three-dimensional space it takes a two-dimensional object (a surface) to create a boundary

How is a sphere two dimensional? Surely they meant circular?

Re:I'm having a little trouble with the geometry (0)

Anonymous Coward | 1 year,16 days | (#44853009)

The *surface* of sphere is two-dimensional. Just like the boundary of a (2d) circle is one-dimensional.

Re:I'm having a little trouble with the geometry (1)

djupedal (584558) | 1 year,16 days | (#44853025)

A sphere has an inside surface and and outside surface - pick one :)

Re:I'm having a little trouble with the geometry (0)

Anonymous Coward | 1 year,16 days | (#44853047)

A sphere's surface is twodimensional. A hypersphere's "surface" is threedimensional. (Compare a cube and a tesseract)

I need a brain upgrade (1)

ioconnor (2581137) | 1 year,16 days | (#44852973)

Perhaps as computer interfaces advance so we can use supercomputers seamlessly without even knowing it concepts such as this will become easily understood. Currently I'm hard pressed to figure out how we could test these theories let alone make use of them. We need to upgrade our brains...

God needed? (0)

Mandrel (765308) | 1 year,16 days | (#44852979)

Does anyone have a good response to the first-cause argument for the existence of God(s)? That is, is the creation of the ultimate progenitor of our universe from no-thing/no-laws best explained as being the act of an eternal and powerful supernatural entity, outside causality, that can be defined as "God"? Or is it easier to accept that something has always existed, perhaps allowing the definition of "always" to go beyond our time arrow?

Re:God needed? (1)

PacoSuarez (530275) | 1 year,16 days | (#44853041)

Perhaps I shouldn't answer your question because it is completely off topic, but that argument is just horrible. How does that supernatural entity explain anything? Where did *it* come from?

Not knowing some things is OK. It's certainly better than fooling yourself.

Re:God needed? (1)

zzyzyx (1382375) | 1 year,16 days | (#44853139)

1) There is not necessarily a beginning to all things. Weird things happen when we come close to the big bang, and time might exist only within our own "bubble".

2) Event the causality principle is not something that is 100% certain

3) Prolongating the reasoning, what caused the first-cause? What makes it exempt from the need for a cause ? Why does everything else need a cause ?

4) Assuming that first-cause exists, absolutely nothing says it would be the same thing as what religions call "god".

Branes versus String Theory (1)

PineHall (206441) | 1 year,16 days | (#44853007)

What is the difference between Branes and String Theory? String Theory seems to have about 10 dimensions or so. Do theories with Branes have only 4 dimensions (3 spacial, 1 time)? I thought they were related. I realize this is all mathematical speculation but I wonder.

Re:Branes versus String Theory (0)

Anonymous Coward | 1 year,16 days | (#44853267)

No difference. They're the same thing. A string is a 1-dimensional brane. The higher dimensions in string theory are, therefore, not actually strings.

Wikipedia is your friend. The math and science articles tend to be edited by actual scientists and mathematicians and are really quite easy to read. I wouldn't use it for dissertation research, but Wikipedia is more reliable and accurate than the vast majority of resources out there, digital or print.

My graduate degree is a J.D., and I can pretty much tell you if the science articles are anything like the law articles, then at worse they're incomplete. But the field of law is fundamentally historiographic, which leaves enormous room for conflicting opinions. I've been doing computer science (not simply hacking PHP or VB) for 15 years, and if the physics articles are anything like the computer science and math articles, then they're better than most textbooks--although, that's largely a function of the fact that there are an insane number of crappy textbooks floating around.

questions... (1)

rusty0101 (565565) | 1 year,16 days | (#44853019)

Not sure that the idea of an event horizon as being a 2D object in 3D space is valid. The Event Horizon is not a surface, it's the description of a place in space where information can not pass, because you can't pass information beyond the speed of light. There is no physical surface there. It's not like you could put your hand against this and pull back a stump.

The next question is are the 'D's between the 4D space as a source, and the resulting 3D space related or concurrent? I.e. does our 3D space x,y,z match to some combination of the earlier univers' w,x,y,z? or are we talking about completely separate t,u,v,w generating our x,y,z?

Alternatively is this an example of the string theroy's multiple dimensions being a common source of dimensions for each univers, and that (at least potentially) one could "translate" from one univers to the other by matching up dimensions in one universe with dimensions in the other, through the quantum foam? I can't see the translation into 4 dimenssions would work well for us, any more than I suspect that people would find it disconcerting if 2D cartoons sudenly popped up in our 3d univers. There would be a dimension of the resulting reality missing from the perspective of the translated being. Whether that would mean that the being would cease to exist, would have to learn new ways of representing reality in their mind, or if they would be subject to influences that they wouldn't be aware of because of how someone from that dimension set would nottice the missing dimension in the translated being. (Perhaps not an issue as there are sufficent dimensions actually available in the quantum foam that if you translated to a 4d univers, you would simply pick up the needed dimension on the fly. It may even be that our experiences in 3D space are simply the illusions of dreams in the 4D space, and we exist in both places already.

Re:questions... (0)

Anonymous Coward | 1 year,16 days | (#44853339)

"Not sure that the idea of an event horizon as being a 2D object in 3D space is valid."

But how do you explain the phenomenon that the circumference of the event horizon is identical to the amount of mass you can compact and spread over the surface of a sphere? That is, for any quantum of mass that passes the event horizon, the circumference will expand to the area necessary to incorporate the mass onto the surface while still obeying universal constants--plank's constant, etc? The idea that you fall "into" a black hole is fanciful. There needn't be anything "behind" the event horizon. The event horizon, arguably, _is_ the black hole. Period.

Also, it needn't necessarily be *in* 3D space. That construction doesn't necessarily follow from the evidence. Maybe we're in 2D space. Or whatever. Our words deceive us. What matters is the math, on the one hand, and the empirical evidence, on the other hand. The behavior of a black hole mirrors the behavior you'd expect of a two-dimensional object. You can leave the implications of that up to the suits in Washington--or the lab coats in Cambridge--as Charlie Kelly would say.

The problem with the "event horizon" is (0)

Anonymous Coward | 1 year,16 days | (#44853343)

that we know so little about the universe, how it really works, and what's really in it that there may well be many more things that can easily cross an event horizon than things that are prevented from crossing one; we simply may be completely unaware of the existence of these other things. We are three-dimensional beings only capable of making three-dimensional instruments which have a very limited ability to measure a very small subset of the details of reality ... for all our creativity and ingenuity we may vary well be missing most of what exists and we may even be biologically incapable of even imagining very real components/aspects of the mechanisms and structures of the universe.

Incidentally, I think bad science education (illustrating space as a surface and gravity as dips in the surface) and popular/unpopular media (like Disney's "Black Hole") have probably led to people thinking of an event horizon as a "horizon" on a warped "surface" rather than, for example, a sphere of some radius

What did one flatlander say to the other? (1)

gestalt_n_pepper (991155) | 1 year,16 days | (#44853063)

Dimension of us never got around.....

So... (0)

Anonymous Coward | 1 year,16 days | (#44853075)

Where did the 4D universe come from?

4D or 3D? (1)

Anonymous Coward | 1 year,16 days | (#44853089)

There's been some speculation that the universe is a 3D hologram on a 2D surface. So maybe it could be 3D universes all the way down.

Ah, I see (1)

Ryanrule (1657199) | 1 year,16 days | (#44853147)

No, actually, I dont see at all. Someone call in an autistic savant to deal with this.

the math that proves it (3, Insightful)

slashmydots (2189826) | 1 year,16 days | (#44853187)

There's actually some math that proves this theory.
Baseless claim/theory with zero evidence + inability for anyone anywhere to disprove it = book deal + huge $$$ grant + discovery channel special

You know, like the theory that the entire universe is a gigantic is a simulation similar to the matrix. There was a very elaborate, college-funded experiment to test that actually (as seen on slashdot)

Interactions between 4D and 3D (1)

Dan East (318230) | 1 year,16 days | (#44853215)

The main problem I have with this the 4D universe could (and would) still interact with our 3D hypersphere. Consider a black hole in our 3D universe. It has an event horizon, the 2D surface of which is analogous to the 3D hypersphere. Mass from our 3D universe does cross through that surface and has a profound effect on the structure and behavior of whatever mass is "living" in that boundary. Thus we would expect to see objects instantly materialize as they cross into our 3D hypersphere, and interact with our mass, etc. Even if somehow that 4D black hole is totally, completely insulated from the rest of its 4D universe, and thus there currently isn't any 4D mass breaking the plane of the hypersphere, we should still see remnants of where 4D mass had passed through at some point in the past. For example it would have had gravitational effects, displaced and interacted with mass, etc.

As far as I'm aware, cosmologists have never observed any structures in the universe which could only be the result of some totally external influence. At some point a chunk of 4D mass would have had to have intersected the brane and punched a hole through a galaxy or imparted more mass or energy in some crazy way that would stand out like a sore thumb.

Re:Interactions between 4D and 3D (0)

Anonymous Coward | 1 year,16 days | (#44853245)

Dark matter ?

Re:Interactions between 4D and 3D (2)

Dan East (318230) | 1 year,16 days | (#44853257)

Too homogeneous and perfectly distributed across all galaxies. Whatever it is it is pervasive and mixed in with observable matter.

Re:Interactions between 4D and 3D (1)

mattr (78516) | 1 year,16 days | (#44853269)

Like a quasar?

Re:Interactions between 4D and 3D (1)

mrbester (200927) | 1 year,16 days | (#44853347)

That sounds like the Steady State theory to me.

Well then universes will be all over the place (1)

Ralph Ostrander (2846785) | 1 year,16 days | (#44853249)

And if so can they eat each other and collide like galaxies.

Rubbish (1, Interesting)

Anonymous Coward | 1 year,16 days | (#44853287)

"Afshordi's team realized that..."

Here. Let me correct that: "Afshordi's team imagined that..."

"Thought experiments" are NOT experiments, NOR are they "science". When Einstein used so-called "thought experiments" he was using them as a teaching tool to explain his theories, but we have now a large pool of people who live on research grants doing "theoretical" science and lots of "thought experiments" (which used to be called "day dreaming" and was a good way to avoid doing real work). I refuse to recognize any of this drivel as "science" until it actually involves experiments and data harvested from those experiments... until then it's just subsidized day dreaming with as much value to society as children putting on costumes and playing "make believe". Why four dimensions and not ninety four or perhaps three hundred four? Even if some wild imagination convinces you that at least four dimensions are needed and some razor tells you to keep it simple (and you therefore restrict your daydream to four) that does not mean the real universe conforms to your desires... there could be exactly 62 dimensions for reasons you will never even be able to imagine. The pseudo-intellectual garbage being peddled to the public as "science" these days is truly mind blowing... and meanwhile there are an uncounted number of real, solid scientific problems to be solved by means of actual science that would improve the lives of millions of people. IMHO Afshordi and team deserve no accolades and no particular attention; they'd benefit society more as day laborers picking fruit or as janitors mopping hospital floors. I love SCIENCE but I detest quasi-scientific junk being passed-off as something of value and tarnishing the reputation of real science. There's been so much of this junk showered upon the public that the public now has a lower opinion of completely valid and serious science and scientists than it had four or five decades ago. One big step backward for science, one grand faceplant for all mankind.

Bah Humbug! (sad, weak smile)

fake bs for grants (0)

Anonymous Coward | 1 year,16 days | (#44853309)

Or maybe, you know, they are up against Godelian limitations of their own mathematical systems which they are falsely projecting onto reality. Maybe their whimsical fancies aren't, you know, ACTUALY REAL. How about some hard evidence for all their conjectures? You know, OBSERVATION OF DATA which is able to be INDEPENDENTLY VERIFIABLE in a repeated way.........you know, like SCIENCE and stuff.

lulz (0)

Anonymous Coward | 1 year,16 days | (#44853353)

Reading the comments to this post, no one really comprehends "dimensions." Just be.

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