34 replies to this topic

[JRPomazon]

I've got a question. Is it possible to have a special area with zero gravity on the Earth?

[Tekky]

Any physicists please feel free to correct me, but as far as I am aware; no. Gravity always exerts a force on you. To escape it, you'd have to go infinitely far from the Earth

Of course, if you are referring to experiencing weightlessness, then that's a different kettle of fish altogether... You can go on a special plane trip that flies you on a parabolic path; for part of it you're essentially freefalling and will experience weightlessness, as Prof Stephen Hawking recently did

[Steel Samurai]

With current technology it's not possible, however I believe that once we discover what gravity actually is then it could be possible.

[SL the Pyro]

Gravity has something to do with a strong magnetic pull, doesn't it? Strongest around the equator and (I think) the North and South Poles. Nullifying the magnetic pull (NOT reversing, that'd blow us all into space) might cause zero gravity.

Of course, this is just a random speculation. Correct me if I'm horribly wrong here (I'm guessing I am).

[Steel Samurai]

Yep. You can't get much more wrong than that.

As far as I remember from my physics book there's two theories about gravity; Einsteins and the particle theory. If it were the particle theory it's possible that one could create a sort of nullifier which canceled out most of the gravity acting on an object. However, such technology is hundreds, if not thousands of years away from being developed, unless discovered by accident.

[SL the Pyro]

...Augh...

Well, at least the nullifier part is a possibility... anyone up for inventing a time machine so we can discover the technology and bring it back with us?

[Mystic Kitsune]

If there was a time machine, wouldn't some idiot from the future come back and tell us how to build it?

Unless people no longer desire fame in the future.

[Keen]

There are four fundamental forces in our universe, strong nuclear, weak nuclear, electromagnetic, and gravitational. We can ignore the nuclear forces in our discussion, because their range is limited to less than the radius of a hydrogen atom. Photons are said to be the force-carrying particles for electromagnetic forces, and gravitons for gravity. Gravitons cannot be blocked by any known means; in fact, we have yet to even detect them as real particles. Gravitational forces could be counteracted by electromagnetic forces; actually, mag-lev technology does precisely this, but this is not zero-gravity, just zero-net-force.

Edited by Lord of Drek, 07 May 2007 - 10:30 AM.

[Tekky]

Gravity has something to do with a strong magnetic pull, doesn't it? Strongest around the equator and (I think) the North and South Poles. Nullifying the magnetic pull (NOT reversing, that'd blow us all into space) might cause zero gravity.

Of course, this is just a random speculation. Correct me if I'm horribly wrong here (I'm guessing I am).

Nothing to do with magnetism; I think what you're referring to is due to the fact that the Earth is not a perfect sphere, but buldges around the equator. As F = GmM/r^2; bigger r means less force; so the easiest way to lose weight (mg) is to live near the equator

Although that's neglecting other forces acting on you...

[SteveT]

Just launch a geosynchronous satellite with sufficient mass to counteract gravity at a given point on the earth's surface.

(Disclaimer: BAD IDEA!)

[Keen]

Just launch a geosynchronous satellite with sufficient mass to counteract gravity at a given point on the earth's surface.

(Disclaimer: BAD IDEA!)

Well, I like the sound of it. *Does some calculations.* It looks like we'll need a satellite that has about the same mass as Planet Earth....

[SteveT]

Bigger, unless it's either super-dense or an average of 1.6 meters from the surface of Earth.

[SL the Pyro]

Unless we used anti-gravity technology so that the satelite wouldn't crush the Earth whilst under construction, that'd be impossible. And it'd be pointless if anti-g tech was already invented, anyway.

[Keen]

SL doesn't need any disclaimers!

And yeah, super dense.

[Showsni]

Just go for the weightlessness because everything's falling at the same rate plan. Jump off a tall building. Until you hit the ground, it's as though everything falling with you is free of gravity!

[arunma]

Gravity has something to do with a strong magnetic pull, doesn't it? Strongest around the equator and (I think) the North and South Poles. Nullifying the magnetic pull (NOT reversing, that'd blow us all into space) might cause zero gravity.

Of course, this is just a random speculation. Correct me if I'm horribly wrong here (I'm guessing I am).

Nope, gravity has nothing to do with magnetism. However, the effective gravity is stronger at the poles than the equator because the rotation of the earth partly cancels the gravitational force. This happens because there is no rotation at the poles, but there is quite a bit at the equator. However, this really isn't an instance of gravity changing, but of gravity being partly balanced by a completely separate force. In any case, the effect is very small.

[masterofwind]

The closest thing I can think of to where you can feel slightly that you are in a no gravity zone is being underwater.

[SOAP]

I found this video that totally blows everything in this thread out of the water. Well... maybe not but I found it interesting nonetheless.

arunma, mind explaining this string theory thing for us?

Edited by SOAP, 02 June 2007 - 06:49 AM.

[Splash]

If you want to try feeling weightless while still on Earth, take up scuba diving.

It's not exactly "zero gravity" but trust me, it feels pretty darn close if you even out your weight.

[SteveT]

arunma SteveT (who also knows physics dammit), mind explaining this string theory thing for us?

String theory is a crazy ass theoretical branch of physics designed to reconcile general relativity with quantum mechanics. It does things like smooth out quantum fluctuations in small volumes of space-time and adds five or ten dimensions to the universe. It's rather controversial because at this point, it's about as falsifiable as God. I wouldn't worry about it until it's a little more fully formed.

Edited by SteveT, 02 June 2007 - 03:47 PM.

[Showsni]

(Obligatory webcomic)

[SOAP]

arunma SteveT (who also knows physics dammit), mind explaining this string theory thing for us?

String theory is a crazy ass theoretical branch of physics designed to reconcile general relativity with quantum mechanics. It does things like smooth out quantum fluctuations in small volumes of space-time and adds five or ten dimensions to the universe. It's rather controversial because at this point, it's about as falsifiable as God. I wouldn't worry about it until it's a little more fully formed.

There are a few crazy nutjobs (like me) who believe that these tiny vibrating strings ARE God. Or at the very least they might explain how God works, should strings exist. I think it's an interesting idea to toy around with. If strings exists and they are God God is using them to create matter, then that pretty much makes all of existence literally a giant symphony.

[SteveT]

Well, if you take Deism TO THE EXTREME, you can boil down God to the laws of physics and initial conditions of the universe.

Hard to form a moral code around that though.

[SOAP]

Yeah that's part of the reason Christians are warned not to get too friendly with the idea of String Theory. Another reason is that if it is true, it might end up disproving God's existence once for all. Kinda scary if you ask me but I don't know all the details on all that. It's just what I hear.

[SteveT]

No, that's just standard evangelical paranoia.

[Keen]

Personally, I like Membrane Theory because it's even more out there than String Theory.

[SOAP]

Personally, I like Membrane Theory because it's even more out there than String Theory.

Oh man! That's my favorite. Actually that's the one I think that religious fanatics were afraid would disprove God's existence because it might prove that existence might in fact been completely accidental.

[Masamune]

God can't have accidents?

Cuz I'm thinking, hey, maybe that would explain a lot.

[vodkamaru]

God can't have accidents?

Cuz I'm thinking, hey, maybe that would explain a lot.

The word accident implies an intent. I prefer to think of god as probability. Probability explains a lot, too.

[Masamune]

That's interesting. A lot of agnostics think of God as a probably. Or a probably not. It varies.