Dark Matter Thoughts

[bystander]

G'day Bystander
...
If you only read 1% of the papers that I go through maybe you may get some idea.

G'day Harry

Perhaps if you only read 1% of the papers that you go through, maybe you might get some idea.

[makc]

I guess the LHC has based it's entire reason for being on the info built up over the eons that particles do indeed exist, to which I totally agree and who wouldn't.

Actually those guys who built it, would not. Maybe there are tiny vibrating strings, or maybe something noone thought about yet. The whole point of LHC (as any other experimental equipment) is to break the theory; noone would build so fffffg expensive machinery only to confirm whatever we already know.

Perhaps if you only read 1% of the papers that you go through, maybe you might get some idea.

big red button

[Chris Peterson]

Actually those guys who built it, would not. Maybe there are tiny vibrating strings, or maybe something noone thought about yet. The whole point of LHC (as any other experimental equipment) is to break the theory; noone would build so fffffg expensive machinery only to confirm whatever we already know.

Well, yes and no. Most theories these days are actually too complex to break with any small set of experiments. They are actually made up of many smaller theoretical components, which may or may not be individually testable. Big experiments like the LHC are less about breaking theory than they are about extending theory, and about placing tighter constraints on the range of the free parameters in complex models. I don't think many researchers involved with the LHC expect any major theory to get broken; they do expect to see existing theory supported, however. It's not so much a question of confirming what we already know as it is confirming what we think we know. (That's not to say that the results couldn't turn particle physics on its head, just that they are not likely to.)

[astrolabe]

Hello again makc,

Yes, the double-slit experiment is something that has had me thinking for several years now and, since taking up B&W photography years back, the polarization of light has been thrown into the mix in my thoughts! For instance, I always purchase polarized sunglasses so as to take advantage of their effects on sky and clouds and some reduction of glare off non-metallc surfaces. But the glasses themselves present other phenom such as the elimination of reflections on glass when viewed at about a 35 degree angle. Polarization of sky and clouds is best at 90 degrees to the sun as opposed to facing it or with it to one's back- tilting one's head can enhance this effect.

However, when viewing objects such as hot top streets or brick sidewalks or even sand facing the sun works best. Does this particular effect tell me that partially absorbed/reflected light gets turned 90 degrees after striking the objects? Or is it the high-energy blue spectrum only that is being polarized especially where the sky is concerned because of scattering? Now throw in the slit experiment and one can see that I have a lot to think about.

Such as: Does only the "electro" part of electromagnetism occupy matter at the atomic level with the "magneto" part separated out as a weak attracive field around the matter? In other words, can "electro" and "magneto" occupy the same space at the same time where matter is concerned or does "magneto" only become a halo or fill spaces between particles. To put it simply, is electromagnetism a single or paired concept?

Enough for now, I'm exhausted!

[rstevenson]

... However, when viewing objects such as hot top streets or brick sidewalks or even sand facing the sun works best. Does this particular effect tell me that partially absorbed/reflected light gets turned 90 degrees after striking the objects? Or is it the high-energy blue spectrum only that is being polarized especially where the sky is concerned because of scattering? Now throw in the slit experiment and one can see that I have a lot to think about. ...

Polarization of light is a well understood phenomenon, and concise clear descriptions of it are easy to find on the web. Here and here, fo example.

Rob

[The Code]

... However, when viewing objects such as hot top streets or brick sidewalks or even sand facing the sun works best. Does this particular effect tell me that partially absorbed/reflected light gets turned 90 degrees after striking the objects? Or is it the high-energy blue spectrum only that is being polarized especially where the sky is concerned because of scattering? Now throw in the slit experiment and one can see that I have a lot to think about. ...

Polarization of light is a well understood phenomenon, and concise clear descriptions of it are easy to find on the web. Here and here, fo example.

Rob

What has that got to do with the relationship between, black holes, dark matter, and dark energy? Well They do slate Harry for it!

As well as the other really great posts, Namely: hstarbuck: alter-ego: astrolabe: Which all was a fantastic read, I Must confess, You all missed A very good point made by Harry. Which is: Where does the energy come from, That turns matter, no bigger or heavier than a Dollar bill, into Energy, That wiped out 100,000 people and flattened a city? Did Not that energy get created When the Atom was created? And when you split that atom, all that energy gets released? What other energy do we not know about, stored in matter?

Mark

[rstevenson]

I see I misunderstood the subject of this thread. It's not thoughts about dark matter. It's dark (in the sense of murky, befuddled, unilluminated) thoughts about matter. Now I know; I'll avoid this thread from now on.

Rob

[astrolabe]

Hello rtstevenson,

You are correct, this thread did devolve somewhat. However, the subject of Gravity can by it's own nature be murky. Gravity is difficult to resolve with the the other basic forces in the Universe and so my "thoughts" were trying to do just that-explain Gravity as perhaps the result of the split in an electromagnetic force once the energy level abated or cooled enough to coalesce into a matter state with the electric part binding matter and the magnet part not included in the created matter but still a part of the matter's environment- perhaps like Gravity?

The other element of the thread about the double slit experiment I felt was relative because of light being also electromagnetic and seemingly also possessing a dual nature. That being evident as the invisible nature of photons disappears when it strikes an objectand reveals itself as light, heat or both. And the fact that it is affected by strong gravitational fields resulting in lensing and that it gives off light when it loses an electron.

Other than that, yeah, it's pretty murky.

[harry]

G'day Bystander

You said

harry wrote:
G'day Bystander
...
If you only read 1% of the papers that I go through maybe you may get some idea.
G'day Harry

Perhaps if you only read 1% of the papers that you go through, maybe you might get some idea.

As a moderator I thought you would have a better response.

I would be lucky to read 1% of all the papers printed. Reading 3 papers per day is good enough for me.

[wonderboy]

... However, when viewing objects such as hot top streets or brick sidewalks or even sand facing the sun works best. Does this particular effect tell me that partially absorbed/reflected light gets turned 90 degrees after striking the objects? Or is it the high-energy blue spectrum only that is being polarized especially where the sky is concerned because of scattering? Now throw in the slit experiment and one can see that I have a lot to think about. ...

Polarization of light is a well understood phenomenon, and concise clear descriptions of it are easy to find on the web. Here and here, fo example.

Rob

What has that got to do with the relationship between, black holes, dark matter, and dark energy? Well They do slate Harry for it!

As well as the other really great posts, Namely: hstarbuck: alter-ego: astrolabe: Which all was a fantastic read, I Must confess, You all missed A very good point made by Harry. Which is: Where does the energy come from, That turns matter, no bigger or heavier than a Dollar bill, into Energy, That wiped out 100,000 people and flattened a city? Did Not that energy get created When the Atom was created? And when you split that atom, all that energy gets released? What other energy do we not know about, stored in matter?

Mark

Quite a scary thought that and it makes me think of this Apod.

http://antwrp.gsfc.nasa.gov/apod/ap970407.html


Imagine if humans harnessed the power of a gamma ray burst? maybe these explosions are other races destroying each other lol.

But thats just my overactive imagination again. sorry folks



Paul.

[Chris Peterson]

Where does the energy come from, That turns matter, no bigger or heavier than a Dollar bill, into Energy, That wiped out 100,000 people and flattened a city? Did Not that energy get created When the Atom was created? And when you split that atom, all that energy gets released? What other energy do we not know about, stored in matter?

There is no energy stored in matter. Matter is energy. If you convert a few grams of matter to its energy form, that amount of energy seems large by human standards (standards developed while huddling around campfires). But the energy isn't large in any absolute sense, compared with typical energies released all over the Universe.

The Universe is made of energy, and a small percentage of that energy is in material form. That's all.

[The Code]

Where does the energy come from, That turns matter, no bigger or heavier than a Dollar bill, into Energy, That wiped out 100,000 people and flattened a city? Did Not that energy get created When the Atom was created? And when you split that atom, all that energy gets released? What other energy do we not know about, stored in matter?

There is no energy stored in matter. Matter is energy. If you convert a few grams of matter to its energy form, that amount of energy seems large by human standards (standards developed while huddling around campfires). But the energy isn't large in any absolute sense, compared with typical energies released all over the Universe.

Check this out Chris.
http://www.unmuseum.org/buildabomb.htm

You are correct, this thread did devolve somewhat. However, the subject of Gravity can by it's own nature be murky. Gravity is difficult to resolve with the the other basic forces in the Universe and so my "thoughts" were trying to do just that-explain Gravity as perhaps the result of the split in an electromagnetic force once the energy level abated or cooled enough to coalesce into a matter state with the electric part binding matter and the magnet part not included in the created matter but still a part of the matter's environment- perhaps like Gravity?

The other element of the thread about the double slit experiment I felt was relative because of light being also electromagnetic and seemingly also possessing a dual nature. That being evident as the invisible nature of photons disappears when it strikes an object and reveals itself as light, heat or both. And the fact that it is affected by strong gravitational fields resulting in lensing and that it gives off light when it loses an electron.

That is what I want to try and understand. Electromagnetic force, Is how it should work, In Gravity. But How?

Thanks for taking the time Guys

Mark

[hstarbuck]

I love these discussions, they can rest for weeks and then be resurrected. The answers are out there, we just don't know (all of) them yet. I don't really know where to go with this, because it has branched off to many directions. What has always been amazing to me is that massless photons are affected by large masses (or something else producing effects we call gravity). How about if in the "early divider double-slit" there was a black hole on one side of the divider with just the right mass and position to bend the photons outwards a bit on the way to the slits (or no divider). Would the diffraction interference pattern appear now?

edit: In retrospect, I don't know if this is really the question I wanted to ask, so here is another try: Is there a scenario where a black hole or two could be inserted into the double-slit experiment that would produce results that were counter-intuitive?

[Chris Peterson]

What has always been amazing to me is that massless photons are affected by large masses (or something else producing effects we call gravity).

Perhaps it will help to consider that photons are not massless. They are described as having a rest mass of zero. This is a mathematically useful concept applied to particles that travel at velocity c. But such particles are never at rest. A photon has energy, and therefore has an equivalent mass (and momentum). You can use this mass value even with classical mechanics to come close to describing the behavior of a photon in a gravity field.

How about if in the "early divider double-slit" there was a black hole on one side of the divider with just the right mass and position to bend the photons outwards a bit on the way to the slits (or no divider). Would the diffraction interference pattern appear now?

Yes. A black hole would bend the path a little, changing the curvature of the incoming wavefront. Interference occurs with a two slit aperture regardless of whether the input source has a flat or a curved wavefront.

[alter-ego]

... What has always been amazing to me is that massless photons are affected by large masses (or something else producing effects we call gravity).

One additional point: Space curvature is also affected by photons. Within GR framework, Energy is all that's required to affect space in which it exists; mass is one form, photons another. Clearly, mass is the primary, and intuitive, player we think about most.

[astrolabe]

Hello hstarbuck, Chris, and alte-ego,

Good stuff!............... I mean it, too.

[Martian16]

Dark energy = dark matter squared, is that what you are proposing? What many are assuming to be DE and DM may just be the force created by whatever is holding our entire universe together. If you can compare our universe to a Black Hole, which exerts a certain force due to gravity, as visible energy and visible matter are brought in. The matter and energy that come into the hole are not what causes the force exertion, (although they can contribute). The collapse of the star is what does the trick. Once the Black Hole is set, anything else going in is automatically forced into its singularity-verse, and supposedly cannot escape. If you could take a reading from the perspective of the Matter, once it's inside, you would most likely realize that what matter and energy there is inside cannot have caused such a force to exist whereby everything is held in place so well.

My theory is: eventually all matter and energy do leave a black hole, like a plant breaking out from the soil, into daylight, thus growing, which I have appropriately named, STEM (space/time/energy/mass). Regarding our universe, perhaps, all things will eventually break out from the confines, restructuring back to maturity from the seed it once was, at the big bang inception.

Oh, well, just a few unrandom thoughts... musings, as they say.

[The Code]

Dark energy = dark matter squared, is that what you are proposing? What many are assuming to be DE and DM may just be the force created by whatever is holding our entire universe together. If you can compare our universe to a Black Hole, which exerts a certain force due to gravity, as visible energy and visible matter are brought in. The matter and energy that come into the hole are not what causes the force exertion, (although they can contribute). The collapse of the star is what does the trick. Once the Black Hole is set, anything else going in is automatically forced into its singularity-verse, and supposedly cannot escape. If you could take a reading from the perspective of the Matter, once it's inside, you would most likely realize that what matter and energy there is inside cannot have caused such a force to exist whereby everything is held in place so well.

Interesting. Would be mind blowing to get your head around them numbers. The snag is, nothing can leave a black hole to prove it. The universe is a scary place, the full answer to what the universe really is, will probably be the scariest thing of all.

Mark

[wonderboy]

Are you saying that our universe is a giant black hole and that we are in the process of being ejected from it?


Paul.

[swainy]

Dark Matter May Be Building Up Inside the Sun
Wired Science | 09 July 2010

tc

[bystander]

Thanks, Mark. I actually meant to post this Friday and it somehow got lost in the shuffle. When I saw your post I went looking for where I posted it, not to be found of course. I thought it was an interesting article. Here is the referenced paper:

Asymmetric Dark Matter and the Sun

• Physical Review Letters 105 011301 (02 July 2010) DOI: 10.1103/PhysRevLett.105.011301

[The Code]

Thanks, Mark. I actually meant to post this Friday and it somehow got lost in the shuffle. When I saw your post I went looking for where I posted it, not to be found of course. I thought it was an interesting article. Here is the referenced paper:

Asymmetric Dark Matter and the Sun

• Physical Review Letters 105 011301 (02 July 2010) DOI: 10.1103/PhysRevLett.105.011301

No Probs Bystander, I did Have a look as well, I thought you would of posted that too. It is interesting, Goes somewhat to saying Dark Matter influences most things we think we understand. And I Thought relevant to this thread. Next Question: What process could possibly make Dark Matter? Oops Sorry That,s another Thread.

Cheers

tc

[Chris Peterson]

Thanks, Mark. I actually meant to post this Friday and it somehow got lost in the shuffle. When I saw your post I went looking for where I posted it, not to be found of course. I thought it was an interesting article. Here is the referenced paper:

Asymmetric Dark Matter and the Sun

• Physical Review Letters 105 011301 (02 July 2010) DOI: 10.1103/PhysRevLett.105.011301

It is an interesting idea. Unfortunately, I don't have online access to the paper, so a lot of details are missing. In particular, it isn't clear by what process the Sun would accumulate dark matter. You would not expect the Sun to encounter galactic dark matter with a relative velocity slower than the solar escape velocity. So most material should just pass through the Sun without being captured. Maybe I'm missing something with respect to how the dark matter interacts with itself (since dark matter particles are presumed to be their own anti-particles). I need to see the paper, or a bit better analysis of the work.

[swainy]

In particular, it isn't clear by what process the Sun would accumulate dark matter. You would not expect the Sun to encounter galactic dark matter with a relative velocity slower than the solar escape velocity. So most material should just pass through the Sun without being captured. Maybe I'm missing something with respect to how the dark matter interacts with itself

As, I would assume, Dark Matter interacts by way of gravitationally only, Would not Dark Matter be orbiting the milky way just as the solar system is?

tc

[Chris Peterson]

As, I would assume, Dark Matter interacts by way of gravitationally only, Would not Dark Matter be orbiting the milky way just as the solar system is?

Sort of, but not in a disc. The disc shape of ordinary matter depends on electromagnetic interaction for momentum transfer. The dark matter that orbits the galaxy is in a halo- a somewhat spherical cloud completely surrounding the galaxy. You would only expect the tiniest fraction to be moving with a slow enough relative velocity to be gravitationally captured by the Sun. Maybe that tiny fraction is all that is needed, but I'd like to see how this issue was treated in the paper.