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The Holographic Principle (APOD 16 Dec 2007)

Posted: Sun Dec 16, 2007 10:33 am
by craterchains
http://antwrp.gsfc.nasa.gov/apod/ap071216.html

Well, at least I learned some facts about tea.

The rest is all speculation. :roll:

Posted: Sun Dec 16, 2007 1:42 pm
by orin stepanek
You need to cross your eyes a little to see the teapot. :)
Orin

Posted: Sun Dec 16, 2007 1:47 pm
by Robert Gillette
I question whether the Teapot is a true hologram. If it were, you should be able to see parallax between the teapot and the background as you change your viewing position. Doesn't happen here.

Posted: Sun Dec 16, 2007 4:33 pm
by kovil
Remember, as much information as a hologram might contain, it can't hold water.

If surface area or length is the dominant factor, there is lots more room for more perimeter length in said photo of the different colored areas.

Adjacency is, however, where the fractal ends.

A pot of Russian Caravan with my croissant please Garcon.

Event Horizon Not established nor holographic principle

Posted: Sun Dec 16, 2007 5:01 pm
by TimeTravel123456789
From a brief look at Imagine the Universe from GSFC, Goddard Space Flight Center, I got the feeling that the event horizon has not really been established. While there might be large areas of dark mass or large mass, that does not establish that matter cannot be compressed further or that nothing can pass the event horizon or that information cannot leave the black hole. The observations have supported large masses affecting nearby objects. That does not establish that information cannot leave the event horizon.

So we have large masses affecting other masses in galactic centers and where supernovaes used to be. Does that establish the holographic principle of area is more important than volume for information content?

Not really. For example, imagine surfaces with an unbound area on one side. Information can pass back and forth in the region of volume. Volume would be more important than the surface areas in determining information content of the region. If I smash myself with a trash compactor, my volume has decreased with the same surface area of material. The information content of me has decreased even though I have the same surface area. My unsmushed volume can hold more interactive information than my surface area. Smashed and smushed I have the same surface area, less volume. I have more interactive information with more volume.

I do not see support for the holographic principle and I also tend to think of event horizons as fun ideas that we still need to observationally prove some how.

Wonderful holiday even if you are being abused in some way. I mean I hope things will get better during this holiday time. I know mycomments can be mean sometimes. Things will get better, I hope.

Posted: Sun Dec 16, 2007 5:07 pm
by Derek Brown
I love APOD and save images frequently for private viewing. Thanks.
- - -

I don't understand the text in today's APOD picture. Dec 16, 2007.

All I see is a random dot stereogram of a teapot.

My limited knowledge and old age tells me a hologram requires a monochromatic light source. Star Wars scenes were only 2-D images of a hologram put together as a video sequence. APOD is not video streaming. Viewing stereograms requires time and cannot be put in an animated gif file.

What I am I missing? I must be an idiot or a baboon. No offense to baboons. Please Ignore this message if I am wrong. Thanks. Happy Surfing. Merry Christmas and Happy Holidays too.

P.S.: (why say some people may see this one way or other see something else without giving a full explanation.)

Posted: Sun Dec 16, 2007 5:48 pm
by Qev
Entropy can be used as a measurement for the amount of information a system can hold. Quantum-mechanically, a black hole is maximally entropic: no region of space can contain more entropy than a black hole that fills that space. The amount of entropy increases with increasing mass. The surface area of a black hole is proportional to its mass. Therefore the information content of the volume enclosed by a black hole is determined not by the volume, but by the surface area of the boundary.

At least, that's my rather simplified understanding of it. It leads to the peculiarities of the Strong and Weak Holographic Principles; the Weak is especially strange. Basically, anything occurring in any volume of space can be made exactly equivalent to its two-dimensional representation on the enclosing surface area... making 'volume' an illusion. :lol:

I love the Holographic Principle... it's just so mind-twisting, and the math backs it up, which makes it even more mind-twisting. :D

The image in the APOD obviously isn't a hologram, since those don't work on a computer screen, so it's 'the next nearest thing', a random dot autostereogram. They actually can be animated, though those are more difficult to view properly. I seem to recall one of a swimming shark.

Posted: Sun Dec 16, 2007 6:25 pm
by Storm_norm
anyone else notice the mispelled word "though" in the paragraph. it should be "through"

Holographic Principle

Posted: Sun Dec 16, 2007 8:06 pm
by pcress
Just to pick a nit (or a nat), the holographic principle allows that the area of a "normal sized computer monitor" can contain about 3x10^65 bits of information. That does not mean, as stated, that you can get that much information from the area. To recover all of the available information would require the capability of "reading" all possible states and conditions of entropy, which is impossible (q.v. Heisenberg Uncertainty Principle). Certainly there is a tremendous amount of information that is recoverable, but some elements are mutually exclusive; so while the area of my computer monitor might contain 300 vigintillion (howzat fer a five dollar word?) bits of information, at least half of that information is unrecoverable.

Re: Event Horizon Not established nor holographic principle

Posted: Sun Dec 16, 2007 10:58 pm
by pcress
TimeTravel123456789 wrote: If I smash myself with a trash compactor, my volume has decreased with the same surface area of material. The information content of me has decreased even though I have the same surface area. My unsmushed volume can hold more interactive information than my surface area. Smashed and smushed I have the same surface area, less volume. I have more interactive information with more volume.
On the contrary: if you smash yourself in a trash compactor, your volume will remain (approximately) constant while your surface area decreases. You are mostly water, which is for all intents and purposes an incompressible fluid. You have all sorts of appendages, wrinkles, bumps, etc. that increase your surface area; when compressed into a cube or cylinder, your surface area will decrease, but your volume must remain constant. Of course, there is one way to prove it.... :wink:

Teapot?

Posted: Mon Dec 17, 2007 3:54 am
by christhebetter
I see a teddy bear wearing lipstick. I don't think I'm looking at all of the 3*10^25 bits. >< Or maybe some bits are more dominant than others, I donno.

Posted: Mon Dec 17, 2007 3:06 pm
by DavidLeodis
The 3D effect showing a floating teapot is amazing. :)

Re: Event Horizon Not established nor holographic principle

Posted: Mon Dec 17, 2007 5:59 pm
by BMAONE23
pcress wrote:
TimeTravel123456789 wrote: If I smash myself with a trash compactor, my volume has decreased with the same surface area of material. The information content of me has decreased even though I have the same surface area. My unsmushed volume can hold more interactive information than my surface area. Smashed and smushed I have the same surface area, less volume. I have more interactive information with more volume.
On the contrary: if you smash yourself in a trash compactor, your volume will remain (approximately) constant while your surface area decreases. You are mostly water, which is for all intents and purposes an incompressible fluid. You have all sorts of appendages, wrinkles, bumps, etc. that increase your surface area; when compressed into a cube or cylinder, your surface area will decrease, but your volume must remain constant. Of course, there is one way to prove it.... :wink:
If you smash yourself with a trash compactor, you are dead, no exceptions no exchanged no refunds!!!

I believe you are incorrect though WRT water being incompressible. With increased gravity, or pressure, anything is compressible, even time. If you put water under 77,000 atmospheres of pressure, it heats up to greated than 220deg F but forms a solid like ice. This "Boiling Ice" takes up less volume due to compression.

A trash compactor is insufficient for that task though and the outcome is NOT a pretty picture. :wink:

Posted: Mon Dec 17, 2007 7:11 pm
by Qev
Well, liquid water is incompressible, as are I think all liquids. If you can force a phase-change, that's something else entirely, as it's no longer 'liquid'.

Posted: Mon Dec 17, 2007 7:42 pm
by iamlucky13
From an engineering standpoint, water is incompressible, and you can ignore the change in density in most engineering problems. However, it is compressible and there are occasions where this has to be taken into account. Calculating buoyancy of a deep sea submersible, for example.

At some point, I'd imagine the pressure increase would cause the hydrogen and oxygen to disocciate, and of course, if you can press hard enough, the electrons are forced into the nuclei and you end up with one giant nucelus...a la neutron star.

Posted: Mon Dec 17, 2007 10:55 pm
by rigelan
funny enough, pressure would cause hydrogen & oxygen to form into water, not water to disassociate

The less pressure, the more molecules you will have.

Le Chatlier's Princpiple (I believe, might have to look it up to confirm it)

Why always the same multicolored image

Posted: Tue Dec 18, 2007 5:29 am
by footprint
Hey, I've got a question about these stereograms, or whatever they're called. Of course they were all the rage a number of years ago, but I've always been curious whether they need to be multicolored as they always are. I've never seen one in grayscale, or more "natural" colors.

I assume the near periodicity is more evident in the color schemes used, and it helps realigning the eyes, but is it really necessary?

JS

Posted: Tue Dec 18, 2007 6:03 am
by BMAONE23
http://antwrp.gsfc.nasa.gov/apod/ap071216.html
I have seen a few in B/W but color spots seem to help hold the image better.
You might try setting your screen display to B/W (if you can) and then try it.

Posted: Tue Dec 18, 2007 6:25 am
by footprint
Ahh, should have thought about that first. I took the image to photoshop and converted it to grayscale. Works just as well. I even took the contrast waaay down (-99) and it still worked, but became hard to view past -97 or so.

Refocusing at low contrast however seemed to invert the image more readily (teapot indentation?).

Still would like to see these with a more simplified pattern though.

Re: Why always the same multicolored image

Posted: Tue Dec 18, 2007 7:09 pm
by pcress
footprint wrote:Hey, I've got a question about these stereograms, or whatever they're called. Of course they were all the rage a number of years ago, but I've always been curious whether they need to be multicolored as they always are. I've never seen one in grayscale, or more "natural" colors.

I assume the near periodicity is more evident in the color schemes used, and it helps realigning the eyes, but is it really necessary?

JS
The first stereograms I saw were in a Scientific American article many years ago, and if memory serves they were black and white (not even greyscale). There were also some red/green stereograms, and colored glasses were included with the magazine.

http://www.tabberer.com/sandyknoll/more ... tware.html

Kinda cool.

one teapot or three?

Posted: Tue Dec 18, 2007 7:34 pm
by meimeisuuri
By refocusing slightly (more relaxed) on the stereogram one can see three partial teapots instead of one complete teapot. The visual array is remapped: undistorted left and right teapot thirds plus a overlapping compressed center, more or less.

This remapping of color patches changes the linguistic information, just as it changed from "a bunch of colors" to "floating tea pot" in the first instance. A cypher within a cypher. Question is: what information (other than the transformation rules) is added or subtracted in this process?

Posted: Tue Dec 18, 2007 11:33 pm
by iamlucky13
rigelan wrote:funny enough, pressure would cause hydrogen & oxygen to form into water, not water to disassociate

The less pressure, the more molecules you will have.

Le Chatlier's Princpiple (I believe, might have to look it up to confirm it)
Hmm...I think that's at classical pressures. At some point before collapse into a neutron mass, the atoms must surely be crushed into a configuration where they could no longer be considered bonded to one another.

Posted: Wed Dec 19, 2007 3:41 am
by rigelan
Oh you're probably right. But I wouldn't consider that new crushed form to be oxygen and hydrogen dissasociating either. Smashed into its own obliterating compactness maybe. :-)

Cosmological Teapot

Posted: Mon Dec 31, 2007 2:57 pm
by Mushhushshu13
Where is the teapot thingy anyway???

:?
Plz tell.
Why teapots anyway??

Posted: Mon Dec 31, 2007 9:00 pm
by Qev
iamlucky13 wrote:
rigelan wrote:funny enough, pressure would cause hydrogen & oxygen to form into water, not water to disassociate

The less pressure, the more molecules you will have.

Le Chatlier's Princpiple (I believe, might have to look it up to confirm it)
Hmm...I think that's at classical pressures. At some point before collapse into a neutron mass, the atoms must surely be crushed into a configuration where they could no longer be considered bonded to one another.
Well, at some point you end up with electron-degenerate matter, which is basically a bunch of free-roaming atomic nuclei in a 'sea' of degenerate electron gas. This is what makes up the innards of white dwarf stars.
Mushhushshu13 wrote:Where is the teapot thingy anyway???

:?
Plz tell.
Why teapots anyway??
You need to cross (actually uncross) your eyes the right way in order to be able to view the effect. A quick and dirty cheat to seeing these (assuming it's displayed on a monitor or behind a layer of glass) is to focus on the reflection of a light that's some distance behind you. This gets your eyes into the proper 'distance viewing' configuration to see the 3D image.

Another method (which makes you look ridiculous, but it works) is to lean in as close as possible to the image on your screen, and deliberately relax your eyes (not trying to focus on anything). Then slowly pull back from the screen, still keeping your eyes relaxed. I find this a little more challenging than the first method, but it doesn't require a light source behind you, and you get to look silly doing it. :)

As for why teapots... I think it has to do with early 3D modeling culture. Teapots are a collection of fairly complex shapes that (used to be) pretty computationally expensive to render in animation. Or so I've been told. :)