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NASA Finds Direct Proof of Dark Matter
NASA News ^ | 21 Aug 2006 | Erica Hupp

Posted on 08/21/2006 6:13:30 PM PDT by vikingd00d

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To: Cold Heat
I have never met anyone who claims to know everything about gravity. If that were the case, why are we still using rocket propulsion and making a bird that has to fall out of orbit and endure reentry heat to land like a jumbo jet.

You are showing an inability to distinguish physics from engineering. The theory of gravity only tells us what forces that rocket will experience. Building a vehicle that is strong enough to overcome those forces is not physics. That is engineering. Therefore: if physicists begin to understand gravity even better than we already do that will have no effect on rocket construction unless we move into some fictional star trek world with anti-grav devices.
81 posted on 08/22/2006 9:10:46 AM PDT by newguy357
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To: vikingd00d
The concentration of mass is determined using the effect of so-called gravitational lensing, where light from the distant objects is distorted by intervening matter.

If dark matter only interacts through gravity, what is the light coming from to determine where the dark matter is located?

Sounds like there are still research opportunities here.

82 posted on 08/22/2006 9:26:34 AM PDT by <1/1,000,000th%
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To: newguy357
Uhhh, yes. Just like anyone who has taken freshman physics in the last 100 years should. It is taught in the EM portion of freshman physics. It is quite intuitive. Visualize a spherical conductor. Remove an electron from the center. What happens? An electric field is set up from that positive charge. What happens because of that? One of the free flowing electrons in this conductor will move along that electric field into the center where the previous electron was vacated, thus negating the original electric field but creating a new one further out (radially) of the same magnitude as the original. That causes an electron from further out to repeat the above. Do that many times and pretty soon all your charge is on the surface. That is basic physics and no one has questioned it for a century.

Hmmmmmm, I don't think that is the explanation for the surface flow. It explains the basic phsysics of the flow of electrons, but not the type of flow and why it behaves in specific ways..

The logical explanations have been varied, but the flow of electricity basically starts out as a turbulent and chaotic flow, just as a liquid flows within a pipe. As time progresses and we add Milli seconds to the event, the chaos that tends to expand outward creates a laminar flow on the outside of the conductor, or in liquids, the pipe. laminar flow allows for a more efficient flow rate and less resistance. This is why multi-stranded conductors are less resistive, creating less heat than the solid variety.

This is the layman's explanation that we use in the field where we know that electricity, like a liquid, seeks the path of least Resistance on it's own. And no, we have not known this for a hundred years. And no, it is not that simple. we are constantly trying to improve wiring methods, and the field procedures we use to improve the process, just as they do in fluid mechanics by improving valve and piping designs.

Efficiency is the game, and with improved efficiency we lower costs and reduce weight. we are constantly learning, and nobody can tell me that we know all there is to know. Except maybe a engineer, because they tend to do that all the time.....:-)

There is constant friction between the field and the guys with the pencils...There is no formula, that I have ever been aware of that describes and can predict the efficiency of the flow, but over time we have made note of the better wire and cable designs as far as number of conductors on the bundle vs the conductor size required. wire engineers have this at their figertips, and I simply pick from the best quality based on practical experience.

I am the guy in the field who has to build the stuff the engineer conceives on paper...I usually do a pretty fair job of smoothing out the bumps between concept and reality, but it is not easy. Only 35 years ago, we had this all wrong, and were building electrical distribution systems that were faulty and could have been much better. We are constantly improving, and by no means do we understand it all.

That is why I responded to your claims. The mind set should be that we know that we don't know everything. Not that we do....Electricity is certainly no exception.

83 posted on 08/22/2006 9:40:51 AM PDT by Cold Heat
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To: Physicist
It is not made out of any known type of particle. It can be bound gravitationally, as we see here, but it does not form clumps like stars or dust grains.

As for the black hole question, as luck would have it, I answered that before.

Thanx.

84 posted on 08/22/2006 10:10:14 AM PDT by longshadow (FReeper #405, entering his ninth year of ignoring nitwits, nutcases, and recycled newbies)
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To: newguy357
His only point is that when designating this in a circuit diagram the convention is to show which way positive current flows, even though what's providing the currents are electrons which are moving in the opposite direction.

We are not on the same page here, which is not unusual when I make a statement on the thread that a engineer wants to parse, which is what they do with a BLT sandwich or anything that anyone says.

I simply mentioned the hole theory. Nobody really cares which way a electron moves in a circuit diagram, because you just need to pick one way or the other to make calculations. In the field, it helps if you wire the power supply correctly.

Here the deal! I had a exchange up the thread with another FReeper, in which we marveled at the amount of things we know and more importantly, what we don't know.

You guys jumped in and blasted the statement referencing what we don't know, as if to say we know all we need to know and have known it for a while.

My contention holds that we don't understand enough to pick our own nose on a variety of subjects. Only a fool would say we know enough, when in fact, we only know enough to be dangerous.

Your commentary on electrical flow is a great example. Electrons move radially, only because of the atomic structure of the conductor. It is the way the atoms are stacked that causes the radial movement, and the end result that a signal applied to one end takes time to get to the other because it travels a much greater distance then that of the wire length. You think we know it all, yet we have yet to produce efficient conductors without dicking around with gold and copper.

Currently, much work is being done to make better conductors that are constructed similar to a polymer chain and will increase signal speed dramatically. We don't yet know how. We don't yet know a lot of things, like how to transmit raw power wirelessly. We cannot even create efficient and safe power economically without putting in more than we take out, excluding nuclear.

So here I simply state the obvious and you all want to parse it.

You cannot parse the truth. The truth is, we are in the dark ages on many levels of development.

All the hundred year old understandings notwithstanding.

The truth is, that we should know that we don't know a great deal....

That's the truth.....Parse it......If you can.

85 posted on 08/22/2006 10:37:04 AM PDT by Cold Heat
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To: true_blue_texican
If the universe is expanding (Big Bang) how could clusters COLLIDE, let alone how could GALAXIES that have been blown apart, collide?

One moving faster than another? Two galaxies with an intersecting trajectory?

86 posted on 08/22/2006 10:48:26 AM PDT by AFreeBird (... Burn the land and boil the sea's, but you can't take the skies from me.)
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To: AFreeBird
intersecting trajectory

It's the "blown apart" part that kind of sets the trajectory.
87 posted on 08/22/2006 11:09:56 AM PDT by true_blue_texican
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To: Cold Heat
Nobody really cares which way a electron moves in a circuit diagram, because you just need to pick one way or the other to make calculations.

Exactly. That was entirely Physicist's point, which is why your objection made no sense. That was my point.

which is not unusual when I make a statement on the thread that a engineer wants to parse, which is what they do with a BLT sandwich or anything that anyone says.

I'm not an engineer, I'm a physicist. Physics requires clarity in definition, just like any other science. I'm not sure why you oppose that.

You think we know it all

Apparently you are only here to argue. Rather than actually reading my posts and responding to what I wrote you have instead responded to what you wish I wrote. If you reread my first post to you I clearly stated my agreement with your premise that there are many things we do not yet understand. Where I take exception is with your specific examples of what you don't think we know. You have used examples which Physicist and I know are already understood in the physics community. No offense, but as an electrician you probably don't know enough physics to tell two physicists what physics is and is not known.

, yet we have yet to produce efficient conductors without dicking around with gold and copper.

Again, you have confused engineering and physics. Is it hard to build an efficient conductor? Who cares? That is irrelevant to our physical understanding of ideal (and imperfect) conductors. If you want to talk about building something talk to an engineer. Gold and copper are not perfect conductors. So what? That has nothing to do with our understanding of conductors.

We don't yet know a lot of things, like how to transmit raw power wirelessly.

Again you show your misunderstanding. Transmitting power is easy. Microwaves are one way. Theoretically we know exactly how to do it. If you want to implement it though, go talk to an engineer and have him try to build one. Regardless, the theory is all understood just fine.

We cannot even create efficient and safe power economically without putting in more than we take out

Ever hear of a little law called the conservation of energy?
88 posted on 08/22/2006 2:31:34 PM PDT by newguy357
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To: newguy357
Another load.....

I'm beginning to tire and I don't tire easily.

I was about to go back and reexplain to you what and why I said what I said about the current direction comment, which quite frankly came out of the blue, and then you do more of it.

So I won't.

What you claim to be my misunderstanding has to do with the neat little box that some of you fellows seem to build around your fragile egos.

This for example........Again, you have confused engineering and physics. Is it hard to build an efficient conductor? Who cares? That is irrelevant to our physical understanding of ideal (and imperfect) conductors.

My post was not confined to engineering. You confined it so it would fit in your little box! A tiny box from my perspective. I was addressing current inadequate conductor properties which very well could involve quantum physics or any number of sciences.

I find this highly irritating when I am wide open and you cannot get out of your box for ten friggin seconds to do anything but insult me for what you mistakenly perceive I said.

I don't and never have confined myself to such a narrow scope as to be so arrogant, but I find it common in your field and that of engineering. I don't know what causes it, but it holds us back.

Get out of your box once and while. Think out side. The world may be untidy, but believe me, you will not achieve squat without digging into the pile.

Maybe that analogy is beyond your perception as well. for example this:We cannot even create efficient and safe power economically without putting in more than we take out

To that you said.....Ever hear of a little law called the conservation of energy?

I don't get it. I thought the sentence was perfectly constructed and clear. I indicated that I do understand conservation of energy and that I am aware of the energy losses we suffer daily because of our outmoded transmission abilities. "More than we take out", certainly does not lead anyone to assume I think there is some way to get more than we put in.

To assume that you would have to believe that I am a simpleton! That I believe in the holy grail! A machine that puts out more energy then it consumes.

The truth is, our energy losses due to transmission are very significant. A large part of it goes up in heat.

Now one would assume when talking to a electrician, that he might have some idea of what he is talking ABOUT. You have done this same leap of logic (sarcasm) for everything I have said on this thread.

The purpose of this reply is to let you know, that I don't like it and I won't put up with it for a new york second. I occasionally learn something on this forum. But not today...no sir.

Since your field is physics, I thought maybe I could learn a little about using quantum physics to transmit signal data over vast distances. Maybe tap the cosmic energy that is all around us to create power on the spot. But you definitely cannot get there from here, and no new theories will ever be written when physicists are in a box. Have a nice day.........

89 posted on 08/22/2006 3:44:25 PM PDT by Cold Heat
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To: Cold Heat
There is a great deal of effects that we use, and don't understand, like why the electrons flow on the outside circumference of the wire?.

Huh? That's where the free electrons are. The ones inside are all shared by multiple atoms, while the ones on the outer surface are free to skip from one to another.

90 posted on 08/23/2006 2:18:19 PM PDT by lepton ("It is useless to attempt to reason a man out of a thing he was never reasoned into"--Jonathan Swift)
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To: Cold Heat
There is no formula, that I have ever been aware of that describes and can predict the efficiency of the flow,

No?

It's related to surface area...which is related to gauge.

At a glance, I'd say that for copper the function of ohms per thousand feet is something like subtracting 10 from the gauge, dividing that by 10, and taking the antilog of the result. That seems to get you pretty close.

91 posted on 08/23/2006 2:54:51 PM PDT by lepton ("It is useless to attempt to reason a man out of a thing he was never reasoned into"--Jonathan Swift)
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To: lepton
You are sorta making my point, and confirming what I was taught years ago on this subject....

As of now, we have a free electron theory, a radial movement theory, and my own chaos theory, and that is just three people.

This is what they instructor told me some twenty five years ago, that there was not agreement.

But, that was not the subject of the thread, and I digress. I made a mistake and pointed out that we don't know what we don't know, and apparently I have learned that we actually don't even know that we don't know.:-)

Have a nice day......

92 posted on 08/24/2006 6:23:48 AM PDT by Cold Heat
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To: Cold Heat
As of now, we have a free electron theory, a radial movement theory, and my own chaos theory, and that is just three people.

No. What you have labelled as a "free electron theory" and a separate "radial movement theory" are one and the same. The free electrons go to the outside exactly because of the radial movement of charge which I described to you earlier. If you had the most basic knowledge of physics you would have known that. By not knowing that you are proving my point. You don't understand the underlying physics, which is perfectly fine. Not everyone is a physicist. The problem is you are boldly declaring what physicists do and do not understand based upon what you personally do and do not understand. As Physicist and I have said, there is no controversy or lack of understanding of electrical flow in the physics community. Yet you, someone who is not a physicist by any stretch, are declaring there is a lack of understanding in the physics community, something you are not part of. Go take basic freshman physics and then get back to me.
93 posted on 08/24/2006 6:29:47 PM PDT by newguy357
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To: newguy357
Actually, you don't know as much as you think.

As a electrician, I deal with A/C currents, not DC. In DC, the flow is pretty much equal throughout the cross section of the wire. It is in A/c where we have the problems in transmission.

A large portion of the problem is caused by the frequency, which causes induction in the wire's central core. The higher the frequency, the more induction. This forces the current to the outside.

There are a lot of reasons why the surface of a wire catches hell, and why we silver coat some conductors, and copper coat aluminum and steel conductors.

I came here to see if I could learn something......Guess not...

94 posted on 08/24/2006 7:11:48 PM PDT by Cold Heat
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