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#8830 08/22/06 05:39 PM
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US astronomers say they have found the first direct evidence for the mysterious stuff called dark matter.

Dark matter - which does not emit or reflect enough light to be "seen" - is thought to make up 25% of the Universe.

For the rest of the story:
http://news.bbc.co.uk/2/hi/science/nature/5272226.stm


DA Morgan
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#8831 08/22/06 06:05 PM
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Good find.

I'm a little confused by these parts:

Stmt 1: "Dark matter - which does not emit or reflect enough light to be "seen" - is thought to make up 25% of the Universe."

Stmt 2: "This provides the first direct proof that dark matter must exist and that it must make up the majority of the matter in the Universe."

I've heard statements comparable to 2 previously.
I'm having trouble assimilating these: Is it "25%" or is it "the majority of the matter in the Universe?" Or am I missing something?

#8832 08/22/06 06:31 PM
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From what I can recall 'normal matter' makes up about 5%, 'dark matter' about 25% and 'dark energy' about 70%.

So 'dark matter' is the majority of matter as 'dark energy' is not matter.

If you see what I mean.


Eduardo
Resistance is futile. Capacitance is efficacious.
There are 10 types of people in the world... Those who understand binary, and those who don't.
#8833 08/22/06 06:33 PM
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Quote:
Originally posted by TheFallibleFiend:
Good find.

I'm a little confused by these parts:

Stmt 1: "Dark matter - which does not emit or reflect enough light to be "seen" - is thought to make up 25% of the Universe."

Stmt 2: "This provides the first direct proof that dark matter must exist and that it must make up the majority of the matter in the Universe."

I've heard statements comparable to 2 previously.
I'm having trouble assimilating these: Is it "25%" or is it "the majority of the matter in the Universe?" Or am I missing something?
I read on wikipedia that there was an experiment which claimed to detect dark matter passing through the earth, but apparently other experiments conflict with it. That may be where you heard statement 2.

Also, the 25% is the majority of matter in the universe because 5% is regular matter and the rest is dark energy.

#8834 08/22/06 07:57 PM
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I'll try to answer each in order.

1. "seen" is a relative term. That does not mean optically but rather more like "seeing" xrays or seeing gamma rays.

2. The universe seems to be have three primary constituents in terms of mass:
A. regular matter ~5%
B. dark matter ~25%
C. dark energy ~70%

Each a decidedly different entity with decidedly different properties


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#8835 08/24/06 01:14 PM
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I missed this. Yes! Of course!
thanks,
k

#8836 08/24/06 04:39 PM
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http://preposterousuniverse.com/images/1e0657-odx.jpg

Stipulated that dark matter is only interactive with gravitation - no collisional scattering or EM anything; e.g., neutralinos - and therefore Big Bang hot for lacking radiation mechanisms. How did both dark matter distributions remain spherical while passing through their distorted baryonic mass distributions of origin and each other?

Can two spherical dust balls pass through each other without collisions but with gravitation turned on (Newtonian or otherwise) and remain spherical?


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#8837 08/24/06 06:58 PM
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Uncle Al's response to this is very interesting.

I know that everything that is said about dark matter is speculative, but there are a few questions that can be raised.

Dark matter (DM) is supposed to interact with ordinary matter only by means of gravity. With no radiative interactions with the visible matter (VM), why is DM not blazing hot? Unless, of course, it was formed after the Big Bang. This could be regarded as raising a question or giving a hint. (Hints about formation and properties.)

The other idea that Al is raising is that two balls of DM pass through one another with no obvious distortion. Is it acting like a point mass? No. Is it acting like a cloud of (dark) particles? No. Is it acting like a continuous fluid? No. Hmm, ... So does that means that DM doesn't interact with DM via its own gravity?

I'm starting to get the idea that DM is like the luminiferous aether of the 19th century. It seems to have many mysterious properties (rigidity, lack of motion, etc.) and it cannot be detected just like a subtle imponderable fluid. Could it be - gasp - that our understanding of gravity is not up to par?

The hypothesis of DM (and dark energy) can explain some things and that is well and good. However, can it, in principle, be falsified? One could ask for other alternative hypotheses. Are there any?

I suspect that when other facts become clearer that some of the dark stuff will go away. The facts I have in mind include AGNs and galactic structure, current mysteries about galactic evolution, certain results in particle physics and the like.

I am not trying to be negative - I am hoping for new physics!

Dr. R.

#8838 08/24/06 07:37 PM
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perhaps dark matter is ablaze with dark energy. since we cant detect the dark energy, we cant see how bright it is. another point i wondered about, since dark matter goes places that matter does not, ie, intergalatic space, and stays away from galaxies, i wonder if it is repelled by gravity.


the more man learns, the more he realises, he really does not know anything.
#8839 08/25/06 11:28 AM
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Quote:
Originally posted by Uncle Al:
http://preposterousuniverse.com/images/1e0657-odx.jpg

Stipulated that dark matter is only interactive with gravitation - no collisional scattering or EM anything; e.g., neutralinos - and therefore Big Bang hot for lacking radiation mechanisms. How did both dark matter distributions remain spherical while passing through their distorted baryonic mass distributions of origin and each other?

Can two spherical dust balls pass through each other without collisions but with gravitation turned on (Newtonian or otherwise) and remain spherical?
Consider the following: If one postulates that all matter consist of fields, and not particles; then, for example, an electron is a localised field: i.e. it has size. But in order to react like an entity, the field has to be in instantaneous contact with itself (time does not exist "within" such a field). One can then postulate further that when two electrons "entangle" they form a new "holistic" field with charge 2e which is in instantaneous contact with itself; even when this field spreads through space. After it has spread light years a spin measurement "disentangle" the holistic field into two components; because the field is instantaneous contact with itself before it disentagles the spins of the electrons are correlated (EPR paradox).
It might now be possible that larger amopunts of materials can entagle to form a holistic field; for example, it has been shown experimentally that "buckey" balls can diffract. Such fields all have to be bosonic in character; thus baryonic matter will not interact with it except through gravity. For this reason an entangled buckey ball can move through two slits and interfere with itself. If the primordial matter consisted entirely of such large bosonic matter; wich is in instantaneous contact with itself; then the initial rapid inflation of the Universe is possible; just like a bi-electron wave extending over light years can instantaneously collapse into two electrons when a spin measurement is made, the primordial "dark" matter should have been able to expand into a large Universe in which afterwatrds baryonic matter started precipitating out. This implies that baryonic matter exists in a sea of dark matter where the latter is in instantaneous contact with itself: this can, in turn, explain why baryonic matter is fairly uniform in our Universe.

In fact, it is possible to entangle more than two electrons. I have generated such a phase in my laboratory between an n-type diamond surface and a gold anode. Independent verification by Prof. Terry Doyle at the University of Kwa-Zullu Natal showed that the phase forms very quickly (the camera speed used was 1/30th of a second per frame and it forms from one frame to the other) and is a perfect pitch-black cylinder. It is superconducting but does not transport the charge from the diamond to the anode by means of a current. It is not possible to do so because there are no independent charge carriers within the phase: i.e. all the electrons are entangled to form a single holistic field. The electrons injected at trhe diamond surface disappears and electrons appear simultaneously at the anode: teleportation?
I believe that the latter phase is "dark matter" consisting entirely of entangled electrons. Recent measurements are giving results that we believe can only be explained by the Meissner effect. Prof. Doyle will be doing more measurements to confirm or disprove the latter conjecture.
Dark matter in the Universe could be neutral dark matter. Maybe we will learn in the future how to entangle with dark matter and go "where no man has gone before". I salute you Captain Kirk. Beam me up Scotty! laugh

#8840 08/26/06 06:06 AM
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Bullet Cluster Shoots hole in Electric Universe

This confirmation of the predicted behavior of Dark Matter may shoot some holes in the Electric Universe idea,and certainly shoots down the Intergalactic Gravity folks.

I thought this article summed up the implications best:

http://physicsweb.org/articles/news/10/8/17


Erich J. Knight


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#8841 08/28/06 04:53 PM
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Dark or anti-matter is real. In Isaiah 50:3, God says, "I clothe the heavens with blackness."

#8842 08/28/06 05:47 PM
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Tim wrote:
"Dark or anti-matter is real. In Isaiah 50:3, God says, "I clothe the heavens with blackness."

I you know for a fact that this refers to dark or anti-matter.

Do you understand that there is absolutely no relationship between dark and anti-matter? Apparently not.

Do you know what your religion claimed that passage referred to 100 years ago before the discovery of anti-matter and dark matter? How about what your religion claimed about that passage 200 years ago? 300 years ago? 500 years ago? etc?

Your modern day interpretation is invalidated by the very claims of your religion in the past. You can not redefine biblical truth every 50 years just to play catch-up with serious science.


DA Morgan
#8843 08/28/06 09:11 PM
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That seems to me what science is doing. This verse was written before the universe and space were able to observe. If someone was just writing poetry, he would have said the heavens were blue because 2,700 years ago that it is what it would have seemed like. A great scientific website is at www.icr.org

#8844 08/28/06 09:18 PM
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At night - without the sun - the "heavens" were and are black.

www.icr.org is NOT a scientific website. The Institute for Creation Research doesn't do anything that actual scientists would recognize as research and is not a scientific organization.

ICR is a group that promote pseudoscience. There arguments are long refuted, however, they can seem very convincing to people who do not know anything about the subject and refuse to actually try to understand the subject.

#8845 08/29/06 05:11 PM
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I myself have studied many of their theories and scientific observations for hours upon hours and have found them to be correct. I want to ask you if you have multiple Ph.D.'s in science like some of ICR scientists have.

#8846 08/29/06 05:37 PM
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I do not have even one PhD. But having a PhD does not make one an expert.

almost all of the ICR "scientists" are tenth tier nobodies. The nobel laureates say that evolution is real science and ID and creationism are not. Same for the leading scientific associations.

Collectively, they have contributed VERY little to their fields.

#8847 08/29/06 11:28 PM
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I wrote:
"You can not redefine biblical truth every 50 years just to play catch-up with serious science."

Tim wrote:
"That seems to me what science is doing."

That's right Tim. That is what science does. Because science is the search for truth. It does not claim to be the truth. It does not claim to be the word of some entity that has perfect knowledge. And thus science is free to learn more and change its explanations as it progresses.

But you can not claim that Genesis means one thing in 1706, another thing in 1806, another thing in 1906 and still another thing in 2006 because REAL scientists have proven conclusively that your religion was wrong. Doing as you have done invalidates your belief system.

Either the book is what you say it is or it isn't. Period. For you to change the explanation is essentially an admission that everyone that told parishioners about that passage for the last 1600+ years was a liar. Is that what you are saying? And it is also therefore permissible for someone in 2106 to explain it completely differently and thus call your explanation untrue.

You can't have it both ways. Was the explanation of that passage in 506 correct? How about 1006? 1506? 1706? 1906? In which year did they get it right?


DA Morgan

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