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StarLab
2004-Nov-19, 05:38 AM
Alright, so most of us are aware of striking similarities, which Mark McCutcheon vainly pointed out in his own attempt to defraud every scientist since galileo.
Now, let's go over the differences, for reference, so...

What makes a magnetic field different from a gravitational one?

Matthew
2004-Nov-19, 06:37 AM
There is both an attractive and repulsive force, as such there we know not of "anti-gravity".

antoniseb
2004-Nov-19, 02:09 PM
Originally posted by StarLab@Nov 19 2004, 05:38 AM
Mark McCutcheon
I think you give this guy too much credit by even mentioning him and his theory, especially outside of the Alternative section, but if you have to, why not just add something to one of the many final theory threads?

StarLab
2004-Nov-19, 05:04 PM
Because this thread is not about that...this thread is just so we can discuss differences between gravity and magnetism...

Darth Maestro
2004-Nov-19, 06:56 PM
As stated in a different topic, gravitational force is extremely weak. The whole gravitational field of the earth is overcome by every human every time one jumps up (only to be overcome again .... hence you don't keep going strait up). Have we been able to capture a single graviton yet? From my understanding, certain people working at particle accelerators are trying to isolate one. If they do, they can learn more about the force of Gravity and dimensions if they exist.

aries_4_5_48
2004-Nov-22, 06:04 PM
......I had always assumed that they were two different 'forms' of the same thing. Secretly I think gravity, as we most commonly think of it, repels. It is a + and - Universe, and we are getting close to 'seeing' things very differently. As Mr. Einstein said:"If at first the idea is not absurd, then there is no hope for it."(think Galileo, Newton......) :o It is also interesting to note that throughout history scientific miscalculations tend not to be entirely false, just off by 180*

fairchilde
2004-Nov-24, 04:32 PM
Originally posted by StarLab@Nov 19 2004, 05:38 AM


What makes a magnetic field different from a gravitational one?
This is a great question, one that I am currently researching. More so I would like to know how gravity effects magnetism and vice virsa.

Keep it up star, and don't let close-minded people discourage you from looking at every angle. :P

bossman20081
2004-Nov-27, 05:50 PM
They are both caused by different things. A magnetic field can be created by running an electric current around a piece of iron, or when all of the electrons in an a piece of iron line up. (this occurs because an electron rotating around the nucleus of an atom creates a magnetic field and when they line up, its more powerful and focused) A gravitational field is a geometric shape caused when a massive object distorts the space around it (I hope I worded that right).

Also, gravity is attracted to everything while magnetism affects only certain things, namely anything that carries a charge.

Sphinx
2004-Dec-02, 02:25 AM
I didn't even know that this was such a mind boggling question until now. Thanks star. I've just recently started researching magnetism without any prior academic study of physics and only an introductory class to chemistry so I'm alittle disadvantaged in this regard. So this topic is really exciting for me. I guess I'm not contributing but 1) expressing my appreciation of the topic and 2) trying to influence the nature of the discussion to my benefit. Again, thanks....

oh, this might apply here. Tomarrow I might be picking up a small motor to build a Van Der Graaff generator to aide in my study of magnetism and electrostatics. A big factor in electrostatics seems to be surface area of oppositely charged substances where as gravity is the effect of mass without regard to polarity.

Moseley
2004-Dec-02, 03:16 PM
Lovely interesting topic - learning plenty, unable to add much.
It strikes me that we need to create a gravitational field, where there was none, in order that we can observe its effects and their speed etc. I appreciate this is not easy in the same way that we can create a magnetic or electric field. Something for the high-energy physicists I presume.

wstevenbrown
2004-Dec-02, 06:26 PM
As a polar force, magnetism can be screened or negated by interposing objects of the opposite polarity-- the same argument applies to the electric force, as they only occur together. You can't screen gravity, tho. Interposing another massive object only adds (well, vector-sums) to the attractive force.

You're on fertile ground here, Starlab. I would be personally grateful if you can get rid of the nasty old Higgs boson. Most unaesthetic. Using a creature like that to 'generate' a mass charge has always seemed to me to be like crashing two locomotives together to produce an HO train. (For the internat'l crowd, a very small scale model toy train)

OTOH,, mommaNature may not be reasonable. Keep up the good work! :) S

StarLab
2004-Dec-03, 01:40 AM
You're on fertile ground here, Starlab. I would be personally grateful if you can get rid of the nasty old Higgs boson. Most unaesthetic. Using a creature like that to 'generate' a mass charge has always seemed to me to be like crashing two locomotives together to produce an HO train. (For the internat'l crowd, a very small scale model toy train)

I can do that for you right now in one sentence, if you'd like: Gravity is not a force, it is geometric. ;)
That's all there is to it. B)

antoniseb
2004-Dec-03, 03:54 AM
Originally posted by StarLab@Dec 3 2004, 01:40 AM
Gravity is not a force, it is geometric.
If you're going to take that route, how can you say that magnetism [and charge] isn't also geometric, using one or more of the many devolved dimensions required by brane-theory? You can make a pretty good case for no true forces at a distance.

Sphinx
2004-Dec-03, 03:56 AM
I think I agree with this last statement. Afterall, doesn't the whole relativity thing actually bend space time to include photons and everything else makeing them geometrical as well?

StarLab
2004-Dec-03, 04:22 AM
No. Photons do not bend, they only curve (unless the star is a black hole ;) )

E/M is a true force. Gravity can be applied in rotational kinematics as acceleration. E/M requires a whole different system. E/M relies on c, whereas KE/PE relies on c^2.

We're talking in genome language here. As in p^2+2pq+q^2=1. Yeah. That kind.


OK, but please, let's drop this tangent stemming from the Higgs Boson, and get back on track. Obviously, members liked the topic, so let's keep it on topic.

ferg.c.
2004-Dec-03, 11:41 AM
Hi StarLab,
Like everybody said, great question! And one that has set of a nice discussion.
The way I see it is this.
Magnetism is cause by a certain type of flux, that is to say a certain movement. A movement of electrons in fact sometimes on quite mind-boggling scales. The most common prodution of this movement is molton Iron swishing about in planet and star cores and not a horse-shoe with ionic imbalances as most folk think.
Gravity is a bit harder to pin down because the actual "cause" of it is still unknown. The opperation of it is however easily observable and measurable so we can at least describe the diffrences between the opperations of gravity and magnetism.
The main one is, as was pointed out above, magnetism has polarity. This means that you can opperate on a magnetic field from different directions and expect to get different results. Whereas with gravity this is not possible. Magnetism does not therefor exibit complete symetery whereas gravity does.

antoniseb
2004-Dec-03, 02:01 PM
Originally posted by StarLab@Dec 3 2004, 04:22 AM
No. Photons do not bend, they only curve
How can something curve without bending? or are you saying the path they follow curves, not the photons themselves [in which case, photons don't curve]?

While we're on the subject, what evidence do you have the gravity is NOT a 'true force' and that E/M IS a 'true force'. How about the force that binds quarks, is that a 'true force'? How about friction, is THAT a true force? I'd like to know more about the distinction between true and false forces.

StarLab
2004-Dec-03, 04:52 PM
Anton, I've started a discussion in the Altheory section so you can carry on our argument there. Please.

Spacefreak2
2004-Dec-03, 09:22 PM
why do you care about this BORRRRRRING space stuff????? i think you should all get a LIFE.

You can buy one on www.getalife.com

This is the best advice you'll EVER have.

BYYEEEEEEEE

bossman20081
2004-Dec-03, 11:30 PM
Originally posted by Spacefreak2@Dec 3 2004, 04:22 PM
why do you care about this BORRRRRRING space stuff????? i think you should all get a LIFE.

You can buy one on www.getalife.com

This is the best advice you'll EVER have.

BYYEEEEEEEE
Please read the title of the website- its called UniverseToday for a reason. What else did you think we would talk about? BTW This is my life- this is what I enjoy doing.

In case youre wondering, I did take offense to that.

StarLab
2004-Dec-03, 11:44 PM
Yeah, even if it was a joke, it was a very bad one. <_<

So speaketh StarMan

Sphinx
2004-Dec-04, 04:37 AM
There really is no need to respond to a comment like that.

Starlab, (or anyone else), can you describe the difference between true and false forces?

StarLab
2004-Dec-04, 06:09 AM
Frankly, there&#39;s no such thing as a "false force," I&#39;m sorry if I gave anyone that perception...either something&#39;s a force or it&#39;s not.

One point of interest is that we have to make a distinction between objects and fields. Gravity is two objects randomly converging on each other due to "tidal" forces. In comparison, electricity and magnetism are version of "fields."

Matthew
2004-Dec-05, 12:05 AM
But there is a gravity field. Another thing in common is that both electric and gravitational fields move at c.

Sphinx
2004-Dec-05, 12:13 AM
so what are you seeing when you sprinkle magnetite over an electromagnet? You are seeing the electric field but is that made up of electrons moving at c within a limited range of mobility?

Matthew
2004-Dec-05, 12:23 AM
No you are not seeing electrons moving at c. If they were they&#39;d break the laws of physics. No electrons move quite slowly. Though the electro-magnetic field spreads at c.

bossman20081
2004-Dec-05, 02:51 PM
Originally posted by matthew@Dec 4 2004, 07:05 PM
But there is a gravity field. Another thing in common is that both electric and gravitational fields move at c.
We dont know how fast gravity moves.

StarLab
2004-Dec-05, 06:34 PM
Note there is a difference between an E/M field and a gravity field. A gravity field can be expressed by m^2, in all relative simplicity. Meanwhile, E/M fields are swarms of electrons and photons in a concentrated area. Only at a certain distance can E/M fields begin to attract each other. If, on the other hand, two objects with a large mass were almost infinitely far apart from each other, the attraction would still exist, in however minute a quantity.

Sphinx
2004-Dec-05, 10:50 PM
Originally posted by matthew@Dec 4 2004, 04:23 PM
No you are not seeing electrons moving at c. If they were they&#39;d break the laws of physics. No electrons move quite slowly. Though the electro-magnetic field spreads at c.

I guess I should&#39;ve known this, but just for clarity the magnetic field is made of electrons, correct? So then how does it spread at c?

Responding to starlab&#39;s post: So what defines something as having a large mass? Are we talking a jupiter sized planet orbiting a solar system on the opposite side of our galaxy exhibiting an effect on another jupiter sized planet in a solar system on the other side? Or are we talking about 2 solar systems exhibiting an effect on one another from opposite ends of our galaxy (or any other galaxy for that matter)?

StarLab
2004-Dec-06, 01:40 AM
Anything higher than protoplanetary level. ;)

Matthew
2004-Dec-06, 04:48 AM
We dont know how fast gravity moves.

We are fairly sure it moves at c. Its never been tested, but we beleive it to be so.

zephyr46
2004-Dec-06, 05:02 AM
Speed of gravity (http://www.newscientist.com/news/news.jsp?id=ns99993232) from New Scientist, suggests the speed of gravity = c.

I guess that is another way of saying, mass can travel to the speed of light, but not faster?

As I understand the Standard Model (http://particleadventure.org/particleadventure/frameless/standard_model.html) (Quick Summary (http://particleadventure.org/particleadventure/frameless/chart.html)) and String theory (http://www.superstringtheory.com/experm/exper2a.html) are in both in vogue at the moment, superstring being the advanced theory. Both accept the graviton (http://pdg.lbl.gov/2001/g033.pdf) as the theoretical (http://www.superstringtheory.com/experm/exper2.html) &#39;Gauge boson&#39; force carrier for gravity, as the Photon is to EM, and yes, the Higgs bosons and feild (http://www.superstringtheory.com/experm/exper2a.html) stuff is messy, but along with the graviton, makes both models work.

Both magnetism and gravity are subject to the Inverse Square Law (http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html).

Interesting discussionHere (http://www2b.abc.net.au/science/wormholes/posts/topic145.shtm) about the smallest black hole possible. There is also discussion on Hawking Radiation, that sounds like a split photon??? :blink:

This would reflect the magnetic nature of light, I guess, or, alternatively a polarity in the relationship between light and gravity?? Or is it just the reflection off the event horizon?

Another question, would anti-matter carry anti-gravity? (I hope I am not stumbling blindly into the alternative theory section here&#33;)

Here is a nice site about Black holes (http://www.gothosenterprises.com/black_holes/index.html)

There seems to be two other threads indirectly related to this one Black hole mass, radius, Black hole (http://www.universetoday.com/forum/index.php?showtopic=5485&st=0) and Does Energy have Gravity (http://www.universetoday.com/forum/index.php?showtopic=5155).

At the center of a lot of the discussions are Black Holes (http://www.gothosenterprises.com/black_holes/outside_black_holes.html), with massive mass (gravity) and magnetic feilds.

Is there a difference between magnetic feilds generated electrically, planetary feilds generated geothermally(?) and naturally occuring magnets? Is the magnetic feild a combination of photons and electrons, does it include Positrons?

It is strange that gravity is so common to us, and yet we know more about and utilise the electro-magnetic feild. The only opposite of gravity seems to be sheer opposite momentum, but we dare not call that anti-gravity. And the thrust to create such momentum comes from a chemical reaction that at the atomic level has everything to do with the postive and negative forces of magnetism.

I thought this would have been very interesting spacefreak2&#33; :)

StarLab
2004-Dec-06, 05:27 AM
Actually, Zeph, now that you bring it up, there does seem to be some conflict between having both a Higgs B and a graviton. Mass and gravity are essentially intertwined - certainly we would not need a separate Boson for both?

I do not doubt the speed of gravity is c, as a matter of fact I think it&#39;s highly plausible...gravity waves are like fluctuations, which in any thought experiment would flow in the fabric of the cosmos quite more efficiently without the presence or need of a Boson.

And, there already is a candidate for an antigravity, called Dark Energy.

Matthew
2004-Dec-06, 05:40 AM
Dark energy is believed to have gravity, for it is always included in where the "missing mass" may be. Well we shall see if there is a Higgs boson when the next big particle accelerator is finished at CERN. Built especially to find the Higgs boson after all, wouldn&#39;t it be funny if they found nothing?

StarLab
2004-Dec-06, 05:46 AM
How do the professional astronomers know they&#39;re not confusing volume with mass?

Matthew
2004-Dec-06, 05:55 AM
They don&#39;t have it confuse StarLab. There is a huge amount of missing mass which is known due to the research on the rotation of galaxies. There just isn&#39;t enough visible mass (in stars and nebula) to account for the rotation of galaxies. For with ONLY the visible mass most galaxies should fly apart, yet the do not.

StarLab
2004-Dec-06, 05:59 AM
Maybe this anomaly can be explained by reducing the volume of the universe taken up by matter and thus leaving room for whichever energy keeps most galaxies from flying into each other?


(I&#39;m trying really hard not to speculate here.)

Matthew
2004-Dec-06, 06:15 AM
But galaxies are not flying into each other (there are some, but they are of no consequence). The force seperating the glaxies, whil is not exactly a force, is the expansion of the universe.

zephyr46
2004-Dec-06, 06:33 AM
I am so glad I haven&#39;t slipped into the Alternative Theory zone&#33;

Yeah, this dark matter/ dark energy stuff hasn&#39;t caught my interest. This is the WIMPS (http://cdms.berkeley.edu/) (weakly interacting massive particles) and MACHOs (http://wwwmacho.mcmaster.ca/) (massive compact halo objects) thing? (links from Wired News (http://www.wired.com/news/print/0,1294,58581,00.html)02:00 AM Apr. 24, 2003 PT. Also Universe Today (http://www.universetoday.com/am/publish/dark_matter_search_proposal.html) (Mar 23, 2004) and the missing mass question (http://www.beliefnet.com/story/17/story_1763_2.html) (Great little intro here (http://particleastro.brown.edu/intro.html))

I don&#39;t know why it hasn&#39;t captured my imagination, probably somthing to do with being mathmatically illiterate, (very nearly totally illiterate eh Kashi :D )

Another link on Dark Matter (http://interactions.org/quantumuniverse/questions/q6.html), introduces the neutralino as the dark matter candidate.

What are the limits of a magnetic feild? Are they Proportional to a magnetic feild?

The Suns (http://www.windows.ucar.edu/tour/link=/glossary/IMF.html)magnetic feild is huge&#33; But is carried and extended by the solar wind.


...gravitational waves are oscillations of the &#39;fabric&#39; of spacetime itself.
Gravity waves (http://www.gothosenterprises.com/gravitational_waves/signals.html)

So when we talk of the &#39;gravity wave&#39; we have to through in the 4th dimension, (time). Theoretically speaking. I haven&#39;t yet heard of a magnetic wave seperate from its feild, other than the photon. I am not sure that we arn&#39;t talking about the same thing when we talk of gravity wave versus the photon. I think we are talking about a really long Photon.

Oh, mathew, the Milky Way is in the process of ripping apart at least three at the moment&#33; Look into the The Magellanic clouds and in particular the The Magellanic Stream (http://antwrp.gsfc.nasa.gov/apod/ap980826.html), the Sagittarius Dwarf Galaxy (http://www.astro.wesleyan.edu/~kvj/sgr.html) and the Canis Major Dwarf (http://antwrp.gsfc.nasa.gov/apod/ap031117.html).

Matthew
2004-Dec-06, 06:42 AM
Yes I know that it is a glaxy eat galaxy universe out there, but my point was that on average all galxies are accelerating away from each other.

zephyr46
2004-Dec-06, 06:48 AM
Sorry :) at the larger distances that is the current theory, based on redshift. But you do know that within the local group, Andromeda and the Milky Way are heading toward each other, the local group is heading toward the Virgo supercluster, and together, we are all heading towards the Hydrus centaurus supercluster and all of them are heading towards the great attaracter, while we are all apparently speeding away from each other at the speed of light&#33;

:blink:

I hope thats right anyway, I don&#39;t think I have left momentum out&#33;

Sphinx
2004-Dec-06, 03:22 PM
what evidence do they have that led to this conclusion? any citations?

Ola D.
2004-Dec-09, 10:24 AM
Originally posted by StarLab@Nov 19 2004, 05:38 AM
What makes a magnetic field different from a gravitational one?
Back to the original question, i just have a few to add here:

A radial gravitational field can be produced around a point or sphere, the same characteristic applies to the electric field, while the same pattern can&#39;t be found for magnetism since you can&#39;t find a single pole standing on its own.

Magnetic forces are stronger than gravitational forces.

You can generate magnetism from electricity or electricity from magnetism, but this fact doesn&#39;t apply to gravitational forces.

I was wondering how does equipotentials of the magnetic field of a rod-shaped magnet look like?

impulseresponse
2005-Sep-20, 01:25 AM
All participants in gravitation are "monopole" like.
Unless you understand P A M Dirac who proposed a magnetic monopole which I think until recently did not have a basis in experimental reality.
Question:
If an accelerating particle radiates energy, where is it getting the energy to both radiate energy and accelerate?

seohtu
2005-Sep-21, 06:14 AM
This post will be incorrect; I'm only posting because I couldn't *not* say something :)

Purely abstract mind-wandering to follow:

I've always thought of electromagnetism as a "verb" and gravity as a "noun", not in the grammatical sense, but in nature. E/M moves, does stuff, is active (that'll be quoted in my doctoral thesis, I'm sure!), while gravity simply "is". No, I'm not remotely able to propose the relationship in better form.. thinking. Like energy is to matter. I (in my delusional daydreams) hope someday electromagnetism comes out to be defined in terms of gravitation, with G being the "universal constant" and everything else depending on it. It just feels.. elegant that way, and the elegant solution is *always* correct, right?

No, I didn't really contribute anything of value, but it might give the more educated among you/us a little food for abstract ramblings as well :)

Sincerely,
Derrick Baumer

---

Today is the last day of your life so far.

Blob
2005-Sep-21, 01:01 PM
As mad as it may seem, there is speculation that magnetic fields affect gravitational fields.

It is thought that a sort of exclusion by entangled Higgs bosons give rise to mass in particles, (envisioned as a warping of space time), and that electro-magnetism fields are mediated by photons. (superconductors exist because of the exclusion of photons by entanglement of , say, electrons); and that the two seemingly unrelated fields could interact…

Thus it may be that you would appear heavier standing next to a magnet.

The underlying multi dimensional Space-time geometry is thought to carry both of these scalar fields (and determines the maximum speed and properties, etc), and that there is some `leakage` between them.

Tim Thompson
2005-Sep-21, 07:11 PM
What makes a magnetic field different from a gravitational one?
If one sticks to classical physics, i.e. Maxwell & Einstein, then there are two obvious, major differences.

First, the divergence of a gravitational field is non-zero, while the divergence of a magnetic field is always zero. That means there are no sources or sinks for magnetic fields (no "magnetically charged" particles), while there are sources for gravitational fields (anything with a nonzero rest mass). So magnetic fields are always dipolar, and vary in strength as an inverse cube, not inverse square, of the distance, whereas gravitational fields are always monopolar, and vary as the inverse square of the distance.

Second, magnetic fields are purely relativistic, and gravitational fields are not. By that I mean that the strength of the gravitational field does not depend on the observer or their state of motion, whereas the magnetic field does. Magnetic fields are created as a purely relativistic reaction to electric charges in motion. An electric charge at rest has no magnetic field, whereas a mass at rest does have a gravitational field.

Caveat:

Having said that, I will add the big observation that in general relativity, there are no gravitational fields. So the real answer is that magnetic fields exist, and gravitational fields do not (you just think they do). General relativity dispenses with the force & field of gravitation altogether, and what we commonly describe as a gravitational field is really only a description of the geometry of space-time.

Magnetism is a real "force", while gravity is not. General relativity replaces the concept of a gravitational field with space-time. On the other hand, quantum field theory, which unifies electromagnetism and the nuclear forces, replaces space-time with the quantum field. That's why it is so hard to come up with a quantum field theory of gravity.

And so the universe really is stranger than you thought.

Blob
2005-Sep-21, 07:54 PM
Here are two links to help.

wikipedia Electromagnetism (http://en.wikipedia.org/wiki/Electromagnetism)
wikipedia gravity (http://en.wikipedia.org/wiki/Gravity)


>>Magnetism is a real "force", while gravity is not...

Yeah, there is currently the new generation theories of loop gravity and the application of the old string theory with Penrose’s 6 dimensional twister space, that may basically show that all the forces are aspects of one super force, present at the big bang, that has frozen out (through symmetry breaking) into the four forces what we see today.

And that, ultimately, all the forces are just an illusion, as are particles, and that every thing is interchangeable; and just each `state` just represents a geometric configuration of the underlying `space-time`(for a bettter word/ branes).

The next big towards in confirming (or disproving) that, er, `grand unified theory`, will be the discovery (or non discovery) of the Higgs particle.

ScienceTeen
2006-Feb-17, 03:33 AM
I think the things discussed here are very interesting I've been searching for things for a science project and I stumbled on this website and I read it all and while I don't fully understand everything I did enjoy reading it. :)

ScienceTeen
2006-Feb-17, 03:36 AM
I'm just a teenager and I'm not that educated in this matter but when I stumbled onto this website and I had read it all I thought it was really cool. Thank u for the information I believe it will help me on my science project very much. :)

ScienceTeen
2006-Feb-17, 03:48 AM
this doesn't really relate 2 the subject but when I read "So when we talk of the 'gravity wave' we have to through in the 4th dimension, (time). Theoretically speaking. I haven't yet heard of a magnetic wave seperate from its feild, other than the photon. I am not sure that we arn't talking about the same thing when we talk of gravity wave versus the photon. I think we are talking about a really long Photon." and I saw it talk about the 4th demension as that of time I couldn't not say anything about what I have read about the demensions.
1st demension is a flat demenion in which we cannot survive. refrence object a straight line.
2nd demension is another flat demension that 3 demensional creatures would be unable 2 survive in. reference object a flat square on a piece of paper.
3rd demension is the demension which we live in. In this demension all objects have depth, distance, and height. refernce object a cube.
4th demension is refrenced as a line within the cube also known as the time line.
5th demension is refrenced as a square within a cube I don't know what it represents but it must come next as the sequence goes line, square, cube repeatably.
6th demension which I believe would be the demension in which something could move through TIME and SPACE at once. It is refrenced as a cube inside another cube. Where going in a straight line from one place to another is NOT the fastest way 2 get there.

sry this had no reason refering to the point.
I just had 2 talk after reading about the 4th demension. :)

Glutomoto
2006-Feb-17, 11:38 AM
just for clarity the magnetic field is made of electrons, correct?

I don't think so.

The electrons are not moving within the magnetic field, they are moving as they normally do within the material that is the magnet.

the magnetic field is the effect/force that is produced, by the spin of the electrons, that are in the magnet material. Further more it is because, the atoms are mostly aligned in the same direction, that is the reason the magnetic force can be detected.

i think.
:)