[Question] What would happen if gravity were removed?

[MemoryLapse]

For fun let's assume the following:

- I have a box inside which is a device that has the capability of nullifying the effects of gravity for everything in a 50' radius.

- Some smart engineers at NASA design a craft that is "spaceworthy" and has some modest, conventional propulsion system i.e. rocket thrusters.

- The anti gravity device is installed in the ship, rendering the ship immune to all gravity in the universe...

With those assumptions I have the following questions:

1. Would the modest conventional thrusters be able to accelerate a craft through space to some useful percentage of the speed of light i.e 99.99999999999999999999999%c?

2. If the spaceship were immune to all gravity, would it even collide with matter in any way or would it bounce off / slip past any matter it came in contact with?

A follow up question-

3. If one were able to accelerate a spaceship to to a very close to the speed of light by this or some other means, would the effect of time dilation cause the universe to shrink to some manageable size, say about the the size of our current solar system? (This is assuming you were able to somehow accelerate a ship to a VERY high percentage of c)

Thank you in advance for any who chose to indulge me on this. If this is the wrong place for this please just let me know.

-Rob

 

[FtlIsAwesome]

Welcome to PF!

Unfortunately, I'll have to say no to your first two questions.

1. Would the modest conventional thrusters be able to accelerate a craft through space to some useful percentage of the speed of light i.e 99.99999999999999999999999%c?

Gravity doesn't come into the equation for relativistic speed and thrust. Literally. This craft would be able to attain "similar" speeds that an ordinary craft could. (It would go faster because it doesn't have to lift-off against Earth's gravity, but it wouldn't reach relativistic speeds.)

2. If the spaceship were immune to all gravity, would it even collide with matter in any way or would it bounce off / slip past any matter it came in contact with?

All of the things we interact with everyday excluding the Earth have extremely slight gravitational effects. Collisions between objects has to do with the electromagnetic force: the repulsion between electrons. So the craft would still crash into stuff like any other rocket would, if set on such a trajectory.

But such a craft would have tremendous advantages. It'd be incredibly easy for it to lift-off and land.

3. If one were able to accelerate a spaceship to to a very close to the speed of light by this or some other means, would the effect of time dilation cause the universe to shrink to some manageable size, say about the the size of our current solar system? (This is assuming you were able to somehow accelerate a ship to a VERY high percentage of c)

Correct, time dilation and length contraction are apparent at high speeds. There's the equation to calculate how fast you would have to go for 14 billion ly to contract to ~80 AU... I don't have the time to do the math right now, sorry. I'll get back to you on that.

 

[IsometricPion]

For fun let's assume the following:

- I have a box inside which is a device that has the capability of nullifying the effects of gravity for everything in a 50' radius.

- Some smart engineers at NASA design a craft that is "spaceworthy" and has some modest, conventional propulsion system i.e. rocket thrusters.

- The anti gravity device is installed in the ship, rendering the ship immune to all gravity in the universe...

With those assumptions I have the following questions:

1. Would the modest conventional thrusters be able to accelerate a craft through space to some useful percentage of the speed of light i.e 99.99999999999999999999999%c?

2. If the spaceship were immune to all gravity, would it even collide with matter in any way or would it bounce off / slip past any matter it came in contact with?

A follow up question-

3. If one were able to accelerate a spaceship to to a very close to the speed of light by this or some other means, would the effect of time dilation cause the universe to shrink to some manageable size, say about the the size of our current solar system? (This is assuming you were able to somehow accelerate a ship to a VERY high percentage of c)

Thank you in advance for any who chose to indulge me on this. If this is the wrong place for this please just let me know.

-Rob

If all of the effects of gravity are removed, then you are left with special relativity and all of the other fundamental forces besides gravity. So, with enough energy you could accelerate arbitrarily close to the speed of light (but the fuel requirements are http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.html" ). If all practical problems (such as space dust destroying the ship, the fact that the accessible chemical energy of the universe is finite, etc.) are put aside, I would say the answer to your first question is yes.

The fact that you do not pass through other matter is a result of the electromagnetic force and the http://en.wikipedia.org/wiki/Pauli_exclusion_principle" . Besides the fact that the matter would not clump together as readily over long time scales (or into such large conglomerations), matter would not be any different (and your interaction with it would not change in any appreciable manner (except as regards objects such as the Earth, Sun, etc. which you normally interact with mostly due to its gravity). So, the short answer to your second question is no.

Length contraction only affects distances in the direction of motion. So, while you could have the distance to the farthest visible object length contract to the distance across the solar system (in principle), the distance in the other two directions would remain the same. (I say farthest visible object because the entire universe may be infinite and no finite length contraction factor can shrink infinity to something finite.)

[Edit: Didn't see FtlIsAwesome's post when I started, looks like we said pretty much the same things, sorry. The speed necessary for a ~3.6E13 contraction factor is ~(1-3.78E-28)c or ~0.999999999999999999999999999622c.]

 

[MemoryLapse]

Thanks for answering those questions. I am particularly shocked to find out that the universe only shrinks in the direction of acceleration. I have some more questions..

1. What do you guys think about the idea of an electromagnetic field being able to cancel out the effects of gravity in a localized area?

2. What would happen if you took a tube of mercury, set it in motion, then ran an electrical charge through it?

 

[Ryan_m_b]

Thanks for answering those questions. I am particularly shocked to find out that the universe only shrinks in the direction of acceleration. I have some more questions..

1. What do you guys think about the idea of an electromagnetic field being able to cancel out the effects of gravity in a localized area?

2. What would happen if you took a tube of mercury, set it in motion, then ran an electrical charge through it?

If you canceled out as much of the spaceship's inertia as possible then it's tiny engines would be able to ramp it up to .9999...c very quickly, the gravity doesn't have an effect though.

To answer your first question gravity is the weakest of fundamental forces, in fact it is 10e36 times weaker than electromagnetism. You can see this easily by picking up a pin with a fridge magnet. The entire mass of the Earth and it's gravity was just beaten by a magnet a few square cm big!

As for your second question I'm really not sure

 

[MemoryLapse]

If you canceled out as much of the spaceship's inertia as possible then it's tiny engines would be able to ramp it up to .9999...c very quickly, the gravity doesn't have an effect though.

To answer your first question gravity is the weakest of fundamental forces, in fact it is 10e36 times weaker than electromagnetism. You can see this easily by picking up a pin with a fridge magnet. The entire mass of the Earth and it's gravity was just beaten by a magnet a few square cm big!

As for your second question I'm really not sure

But how would the ship's inertia be affected by the removal of the gravitational field?

 

[Ryan_m_b]

But how would the ship's inertia be affected by the removal of the gravitational field?

It wouldn't but you asked if

Would the modest conventional thrusters be able to accelerate a craft through space to some useful percentage of the speed of light i.e 99.99999999999999999999999%c?

The removal of gravity wouldn't effect this but if you removed as much inertia as possible this would be a sensible thing to say (as sensible as one can be when talking about removing inertia with a magic black box)

 

[MemoryLapse]

It wouldn't but you asked if

I see what you meant now, thanks.

 

[Ryan_m_b]

I see what you meant now, thanks.

No problem. I'm curious about the mercury question though, what prompted you to ask?

 

[MemoryLapse]

No problem. I'm curious about the mercury question though, what prompted you to ask?

I am working on something involving mercury, electromagnets and gyroscopes. Sadly I have to make nearly everything myself, so I rely heavily on websites like these for your specialized expertise.

 

[Nabeshin]

1. What do you guys think about the idea of an electromagnetic field being able to cancel out the effects of gravity in a localized area?

Obviously it's true that you can, with electromagnetic forces, balance out the gravitational force on a given object. However, you should note that there is no way (electromagnetic or otherwise) to shield or otherwise screen the gravitational force.

 

[Ryan_m_b]

I am working on something involving mercury, electromagnets and gyroscopes. Sadly I have to make nearly everything myself, so I rely heavily on websites like these for your specialized expertise.

Fair enough, good luck with that. I agree with Nabeshin; I didn't make it clear with my example may be but gravity is not being canceled out or negated, merely the force of gravity is being counteracted by the stronger electromagnetic force.

 

[MemoryLapse]

Obviously it's true that you can, with electromagnetic forces, balance out the gravitational force on a given object. However, you should note that there is no way (electromagnetic or otherwise) to shield or otherwise screen the gravitational force.

What makes you so sure?

 

[Ryan_m_b]

What makes you so sure?

Such a thing would violate the equivalence principle. You also might want to read this wikipedia article

 

[phinds]

2. What would happen if you took a tube of mercury, set it in motion, then ran an electrical charge through it?

You don't run electrical charges through things, you build them up on or in things. You run electrical current through things.

If you ran an electrical current through a tube of mercury, its being in motion would be totally irrelevant unless it were moving rapidly close to ferrous metal or moving rapidly in a magnetic field --- a strong one though, not something like the Earth's field (which WOULD have an effect on it but so small I'm not sure you could measure it)

Said differently, an electrical current creates a magnetic field, so any current loop, in mercury or anything else, will be affected if moving in another magnetic field or near objects that react to magnetism.

I'm thinking here that you are talking about running a current from one end of the mercury tube to the other. If you were to run a current across the middle, the effects would be as I stated, but MUCH less since the size of the resulting magnetic field would be much smaller.

 

[NlCK]

If you were somehow able to nullify the effects of gravity, I think you'd quickly remember that you, the machine, the Earth and the sun are(or you and the box/surrounding matter were) gravitationally bound to each other, as well as the Milky Way, the Local Group, the Virgo Super Cluster, etc.. You'd probably wish that you had had time say 'Ow!,' or 'Bye!' and then 'Ow!,' before we tried to figure out what strange phenomenon caused that explosion or reverse shooting star. But, that'd only happen if breaking the laws of physics were to result in anything predictable. On the other hand, maybe you wouldn't test it on earth. Maybe you'd just flick it on and off in space really quickly.Even over a short period of time, it seems like it'd still be kind of difficult to predict exactly how the path(s) of everything else would differ in relation to you. Even with constant monitoring, it may still be pretty tricky to stay out of trouble anywhere except for large, empty, intergalactic spaces. On the other hand, the information that you could gain, or what you could infer about the universe, just by continually observing the apparent motions of everything else, would be fairly awesome. I think that everything would really hinge on how, exactly, gravity actually works. Think about spacetime. Additionally, even without near light speed travel, the cosmic dust/gas and increased radiation exposure could make a pretty nasty a situation.

I am working on something involving mercury, electromagnets and gyroscopes. Sadly I have to make nearly everything myself, so I rely heavily on websites like these for your specialized expertise.

Experiments, thought experiments, and pipe dreams can be a lot of fun. If you're willing to invest a lot of time and thought into projects, such as the one you were mentioning, I'd recommend checking out the https://www.physicsforums.com/forumdisplay.php?f=151".

 

[MemoryLapse]

Ok so this has been useful in helping me understand some things. I am pretty sure the idea of a gravity well drive has been outlined before.

The idea being that if you could nullify the effects of gravity, presumably you could open "holes" in your field and use the gravity of the universe to pull your craft around the cosmos at relativistic speeds. What I am most interested though, is magnets, and how everything is essentially a magnet, including the earth.

When we have electric current, at 90 degrees we have an identical magnetic current (sinusoidal wave). We don't use this magnetic current for anything useful because our electric gadgets and what have you are so small.

So let's do some reverse engineering... Let's take a huge magnet (like the earth) and use its natural magnetic current to our advantage. Tesla was working along these lines but he called magnetic current "naturally occurring electricity". Ed Leedskalnin had the secret figured out, and he was able to use the Earth's magnetic field to move 50 ton stones around his yard like they were Lego blocks. To show off his ability he essentially made a Lego Castle out of 50 ton stones he quarried cut and placed himself.

Our knowledge of electromagnetism is missing something huge and critical. This secret is how ancient man created the giant stone structures, such as the pyramids, we see all around the world. The secret is sitting out there in plain sight, just waiting for someone to rediscover it. I intend to at least TRY to find it.

 

[Ryan_m_b]

Ok so this has been useful in helping me understand some things. I am pretty sure the idea of a gravity well drive has been outlined before.

The idea being that if you could nullify the effects of gravity, presumably you could open "holes" in your field and use the gravity of the universe to pull your craft around the cosmos at relativistic speeds.


What I am most interested though, is magnets, and how everything is essentially a magnet, including the earth.

When we have electric current, at 90 degrees we have an identical magnetic current (sinusoidal wave). We don't use this magnetic current for anything useful because our electric gadgets and what have you are so small.

So let's do some reverse engineering... Let's take a huge magnet (like the earth) and use its natural magnetic current to our advantage. Tesla was working along these lines but he called magnetic current "naturally occurring electricity". Ed Leedskalnin had the secret figured out, and he was able to use the Earth's magnetic field to move 50 ton stones around his yard like they were Lego blocks. To show off his ability he essentially made a Lego Castle out of 50 ton stones he quarried cut and placed himself.

Our knowledge of electromagnetism is missing something huge and critical. This secret is how ancient man created the giant stone structures, such as the pyramids, we see all around the world. The secret is sitting out there in plain sight, just waiting for someone to rediscover it. I intend to at least TRY to find it.

I've heard many claims like this before and I have to tell you they are all bunk. The Earth has a magnetic field yes but that is not what is keeping us on the ground. I would advise you to research this by buying science books on the subjects, do not use websites that espouse these conspiracy theories. Coral castle is an interesting place but aside from conspiracy theories there is absolutely no evidence that it was built through any magical means.

The ancient Egyptians certainly could not turn off gravity. If they could why on Earth would they stay in the desert? Why do we not find Egyptian ruins all across the globe containing these antigravity devices? Truly I implore you to look at the science and not the pseudo-scientific conspiracy theories.

 

[JaredJames]

Ed Leedskalnin had the secret figured out, and he was able to use the Earth's magnetic field to move 50 ton stones around his yard like they were Lego blocks. To show off his ability he essentially made a Lego Castle out of 50 ton stones he quarried cut and placed himself.

Utter non-sense.

The Earth's magnetic field can barely move the needle on a compass - that should tell you all you need to know about its strength.

 

[MemoryLapse]

If they could why on Earth would they stay in the desert? Why do we not find Egyptian ruins all across the globe containing these antigravity devices? Truly I implore you to look at the science and not the pseudo-scientific conspiracy theories.

Im not trying to start some conspiracy theory laden discussion about science fiction. I am talking about the work of actual modern scientists, whose discoveries have gone unrecognized.

You cannot deny that we are missing a critical piece of the puzzle in regards to EM theory. Yes the overall magnetic force of the Earth is weak. But what if there was magnetic current running all throughout that field, the total amount of current would be unbelievably vast AND completely renewable. This current is just sitting there, coursing all over the Earth's entire magnetic field, waiting to be tapped. Tesla did this with his tower. He turned magnetic current into electrical current. His tower was like a lightning rod that attracted the naturally occurring magnetic current and channeled it into usable electricity.

 

[JaredJames]

But what if there was magnetic current running all throughout that field, the total amount of current would be unbelievably vast AND completely renewable. This current is just sitting there, coursing all over the Earth's entire magnetic field, waiting to be tapped. Tesla did this with his tower. He turned magnetic current into electrical current. His tower was like a lightning rod that attracted the naturally occurring magnetic current and channeled it into usable electricity.

What the hell is a magnetic current?

You have a magnetic field which, when moved provides you with an electric current.

The magnetic field of the Earth is incredibly weak. If it was fairly strong, simply moving a piece of wire around with your hand would induce a current in it. As it stands, the magnetic field is so weak that moving a piece of metal around does absolutely nothing.

That first part is complete rubbish. "What ifs" are lovely questions, but with no evidence to support them they mean absolutely nothing.

 

[Ryan_m_b]

Im not trying to start some conspiracy theory laden discussion about science fiction. I am talking about the work of actual modern scientists, whose discoveries have gone unrecognized.

You cannot deny that we are missing a critical piece of the puzzle in regards to EM theory. Yes the overall magnetic force of the Earth is weak. But what if there was magnetic current running all throughout that field, the total amount of current would be unbelievably vast AND completely renewable. This current is just sitting there, coursing all over the Earth's entire magnetic field, waiting to be tapped. Tesla did this with his tower. He turned magnetic current into electrical current. His tower was like a lightning rod that attracted the naturally occurring magnetic current and channeled it into usable electricity.

You cannot claim that there are unrecognized discoveries that we are ignorant of and then claim to know much about them.

To stop this degenerating into crackpottery I'd like to ask the following;

Please outline the evidence (with references) that our knowledge of electromagnetism is missing a critical piece
Please provide references from peer reviewed research as to the existence of a vast untapped magnetic current (though as JaredJames pointed out such a thing isn't even a term)
Please provide references for the claim "I am talking about the work of actual modern scientists" by providing contemporary publications on the issue.

Nikko Tesla is the subject of many conspiracy theories. I'd advise you to check your references. Never did Nikko Tesla build a machine that could extract energy for work from the Earths magnetic field, even if he did why do you think we don't use such a device?

 

[JaredJames]

Just to add, I Googled "magnetic current" and it always points to this guy, Edward Leedskalnin.

Checking him out, he's a crackpot. From the wiki of his creation Coral Castle (emphasis mine):

Edward spent over 28 years building the Coral Castle, refusing to allow anyone to view him while he worked. A few teenagers claimed to have witnessed his work, reporting that he had caused the blocks of coral to move like hydrogen balloons. The only tool that Leedskalnin spoke of using was a "perpetual motion holder."

 

[Vanadium 50]

And to add to ryan's message, if you cannot answer these questions, the thread will be closed.

 

[MemoryLapse]

What the hell is a magnetic current?

I was hoping the bright minds on this forum could help me figure that out.

I am NOT claiming to know anything. I am just a rational person, that sees evidence of lost knowledge all over the globe. I want to figure out what was lost, and I think we are very close. Close the thread if you like. I've learned a lot already and for that thank you!

 

[Ryan_m_b]

I was hoping the bright minds on this forum could help me figure that out.

I am NOT claiming to know anything. I am just a rational person, that sees evidence of lost knowledge all over the globe. I want to figure out what was lost, and I think we are very very close.

I think you just lost your chance to answer my questions. I expect this thread will now be locked.

 

[JaredJames]

You start with:

I am NOT claiming to know anything.

Then you claim to know:

I am just a rational person, that sees evidence of lost knowledge all over the globe. I want to figure out what was lost, and I think we are very very close.

See #23 for the guy who came up with it - crackpot.

 

[phinds]

I was hoping the bright minds on this forum could help me figure that out.

I don't think even the bright minds here are going to be able to help you figure out the characteristics of something that does not exist.

You need to study electomagentism 101

 

[Vanadium 50]

As promised. No physics. Thread closed.