Anti-Gravity

[noz92]

I also edited the Wikipedia article so it gives more information. It's the same information that I have above.

[Natski]

The Swartzschild metric:

 

[math]ds^2 = -(1 - \frac{r_g}{r})d(ct)^2 + \frac{1}{1 - \frac{r_g}{r}}dr^2 + r^2(d\theta^2 + \sin^2 \theta d\phi^2)[math]

 

[math]r_g = 2Gm|c^2[/math] is the Swartzchild radius' date=' and [math']m[/math] is the mass of the source of the field.

 

The Swartzschild radius:

 

[math]R_{sch} = \frac{2GM}{c^2} \thickapprox 1\frac{1}{2} \times 10^{-27}M[/math]

 

[math]R_{sch}[/math] is the Swartzchild radius; [math]G[/math] is the gravitational constant, or [math]6.67 \times 10^{-11} N m^2 / kg^2[/math].

 

[math]M[/math] is the mass of the black hole.

 

[math]c^2[/math] is the speed of light squared, or [math]8.98755 \times 10^{16}\frac{m^2}{s^2}[/math].

 

But anyway, the Swartzschild metric reviels a negative square root solution, along with a positive one for it's geometry. The negative square root solution in the event horizon represents a white hole, which is just a black hole running backwards in time.

 

Apperantly they can't exist, since they violate the second law of thermodynamics. So, I guess I have no more examples of antigravity that I can think of .

 

Thanks for the info on that one. It is interesting though. I remember reading that Dirac (I *think* it was him, not sure) noticed that the relativistic energy-momentum equation...

 

E^2 = m^2c^4 + p^2c^2

 

that for zero momentum obviously...

 

E^2 = m^2c^4

 

and therefore...

 

E = +/- mc^2 (note the +/-)

 

The -ve was always just thrown away as something that had no physical meaning, but when Dirac took the -ve sign seriously he theorised the existence of anti-matter. I seem to remember in optics (Fresnel diffraction I think) another case where the -ve root had an important consequence. My point is I think -ve roots shouldn't be discarded so easily. The math describes the physical world, no matter how strange it may seem.

 

Natski

[Deified]

Aren't Quasars said to be linked to black holes through worm holes?

[The Nacho]

'']I've never heard of a white hole being reffered to as something that may actually exist. How in the world would something like this work, wouldn't it be required to produce matter/energy? Someone enlighten me, wikipedias article on it says basically nothing.

 

I have read that white holes come from black holes. In theory, the only way a white hole could exist would be that there is another universe. When stuff goes into a black hole, it (supposedly) comes out from a white hole in another universe. (The idea of more than one universe is strange, beacuse uni- means one.)

[[Tycho?]]

I have read that white holes come from black holes. In theory, the only way a white hole could exist would be that there is another universe. When stuff goes into a black hole, it (supposedly) comes out from a white hole in another universe. (The idea of more than one universe is strange, beacuse uni- means one.)

 

But why is that even necessary? Black holes have their matter in the singularity, there is no need for another universe to expell the matter. Since then the mass and hence gravity of the black hole would mysteriously drop.

[Crash]

couldnt you get a anitparticle of the virtual graviton?

[Sayonara]

White holes seem like a fairly juvenile idea tbh.

[Severian]

A graviton is Majarana, so it is its own antiparticle (this is true for the photon too).

[TWJian]

Ive had enough i've simply had enough ive been a scientist 42 years i'm not going to put up with this! i know more that all of you put together' date=' the above equation is not of correct efficiency, if you work this out you will realise that the answer is slightly slack and lacking of several decimal places which it should include to be of satisfactory accuracy. back in the days of the Vietnam war i managed to write approximatly 1000 pages on the topic! hus laughinng now eh hahahahah?!??!!

SCIENCE IS NOT A TOY!!!

 

This is plain blatant boasting and degradetion of another's post.If you want to disprove his equations,you should present yours.So much for being a scientist for 42 years.You should know how to disprove someone politely.

 

Here's my view,The universe could be pictured as a flat sheet of rubber with infinite area,and therefore infinite stretchabilty.If mass is placed upon it,it will cause an indention.With the absence of friction,any other mass placed near the indention will travel down it in a rotating fashion.Hence,gravity could be interpreted as geometrical distortion.

 

If we could push the indention back in place,the indention would become smaller,and therefore reduce the effects of gravity.A strong enough electro-magnetic force should be able to partially nullify gravity.However,I think that true anti-gravity cannot be achieved because the 'rubber-sheet' needs to be stretched to an infinite stiffness(hence infinite energy) for that to occur.Someone needs to come up with a working unified field theory to work out antigravity.

[Sayonara]

Sciencemasta has been suspended after a whopping 3 posts, and can come back when he acts his alleged age.

[skamike]

all you need is a unified force pushing you away from the earth at 9.8m/s^2. air jets could work on a very basic level, but you'll still have the aerodynamics to worry about, so it wouldn't be a perfect "weightless room" (I assume that's what we're going for here). you could theoretically acheive it with a magnetic suit and an electromagnetic floor, but there's nothing to stop that from flipping you over and gluing your head to the ground. What it would take is a force that consistantly pushes all matter away from it placed between you and the body of gravity. An equal force would make you weightless. Such a force exists on the molecular level (the name of it escapes me) but i'm not sure we've quite harnessed that one yet.

[ed84c]

hmm does gravity have to be quantised for anti gravity exist?

 

and was the 'strong' electromagnet force you were llooking for Ska mike, as part of QED

[skamike]

strong force, that's the one.

 

and unless you can just turn gravity off, you would have to quantise it in order to produce the appropriate opposing force.

[Severian]

and unless you can just turn gravity off, you would have to quantise it in order to produce the appropriate opposing force.

 

Why do you say that? What does quantising gravity have to do with creating anti-gravity? Anti-particle have positive masses, not negative ones.

[skamike]

by quantise i mean measure. you could trial and error on it i suppose, but with something as advanced as anti gravity you'd want your figures to be correct. my point is pretty simplistic. force x plus force -x = zero. I'm not familiar with the mathematics behind anti-particles and the intangible white hole... i'm simply advocating a push to cancel the pull.

[noz92]

If white holes cannot exist because the violate the 2^nd Law of Thermodynamics, and worm holes are a result of black holes connecting with white holes, would that mean that worm holes can't exist, and therefor (not to get off topic) time travel is impossible?

[1veedo]

I don't think worm holes have to be connected to a white hole. I may be wrong, but I think that idea was just adopted because they needed a way to transport the matter...

[noz92]

I have read that white holes come from black holes. In theory, the only way a white hole could exist would be that there is another universe. When stuff goes into a black hole, it (supposedly) comes out from a white hole in another universe. (The idea of more than one universe is strange, beacuse uni- means one.)

 

The theory that says that black holes lead into other universes was just recently discredited by Stephen Hawking (who apperantly was also the one who created this theory).

[noz92]

Black holes are supposed to suck in matter and return it in the universe as radiation. A sort of cosmic recycling. What if the radiation is released from the black holes sister white hole?

 

The energy going into the black hole is later spewed out of a white hole.

 

Would this be possible?

[Sayonara]

If white holes cannot exist because the violate the 2^{nd[/sup'] Law of Thermodynamics, and worm holes are a result of black holes connecting with white holes, would that mean that worm holes can't exist, and therefor (not to get off topic) time travel is impossible?}

^{No, because the middle bit is just made up.}

[Artorius]

Hasnt it already been proven that a singularity cannot BE.Therefore the matter must go somewhere unless the black hole collapses and the matter is released in an energy burst.But i do not think one has the definitive proof that black holes actually exist.Isnt it just our observations of interaction point us to this hypothesis.

[Crash]

if gravity is a distortion of space time, can there be an anti distortion? i cant see how there could be. If antiuniverses were real would they still have gravity exactly like our own or would it be anti-gravity?

[Crash]

Soz about the double post but i just had another relevant question bout teh white holes, arent they 'supposed to be connected by wormholes to black holes'? i thought one cannot create wormholes so how would a black hole be able to? and if they cant then they cant be linked to white holes, unless blackholes always form over already present wormholes.............

[Sayonara]

Hasnt it already been proven that a singularity cannot BE.

No.

 

Therefore the matter must go somewhere unless the black hole collapses and the matter is released in an energy burst.But i do not think one has the definitive proof that black holes actually exist.Isnt it just our observations of interaction point us to this hypothesis.

If the matter that comprised the black hole was "going somewhere", it wouldn't be a black hole any more.

[noz92]

if gravity is a distortion of space time, can there be an anti distortion? i cant see how there could be. If antiuniverses were real would they still have gravity exactly like our own or would it be anti-gravity?

 

That's what I've been trying to ask.

 

That thing where you put a heavy object like a bowling ball on a trampoline sheet, then roll marbles. The marbles come to the bowling ball. I think of anti-gravity like puting a bowling ball under the trampoline sheet. I was just wondering how such a thing would be possible, and if it turns out not to be, are there any alternatives to this?