Objects with Negative Mass

[Rdivine]

Is it possible to have an object made out of exotic matter which demonstrates properties of negative mass?

A particle of negative mass would accelerate in the direction opposite of applied force, thus pushing an object with negative mass would be impossible, as it would just accelerate in the direction opposite of the push, cancelling out your push force in the first place. This would allow for intergalactic train tracks, where vessels use wheels to push against rails of matter with negative mass, and perhaps infinite energy.

(Infinite energy can be created by , let's say, attaching a very long elastic band to two hooks made of negative mass moving away from each other, and harnessing the elastic potential energy.)

The velocity of a negative mass object can be determined by the initial velocity when it is synthesized, and it would also create more paradoxes. For example, what would happen if two cubes made of negative mass collided with each other? Since their motion cannot be changed by an external force, they are essentially unstoppable. Hence, would the cubes pass right through each other?

All these possibilities sound very cool, and despite being inconsistent with the expected behavior of "normal" matter, negative mass is mathematically consistent and introduces no violation of conservation of momentum or energy.

Now, only one of the statements below are true.

1. Negative mass is possible, allowing for unstoppable objects and (perhaps) infinite energy.

2. The current mathematics regarding the conservation of momentum or energy is incorrect/incomplete.

You can vote on which statement you would think is true in the polls above! Meanwhile, share your opinions below!.

 

[SomeGuy123]

Option 2 is more likely to be true than option 1.  Experimental evidence >>>>>>>>>>>>>>>>>>>>Theory.  Anything you observe the real world doing consistently is truth.  Anything you don't see or have evidence of is just wishful thinking.

There are undiscovered tricks in nature, maybe radically different physics no one has ever observed, but there is no particular reason they would adhere to anything in current theories.

[BagelRabbit]

There are a few problems with your logic, unfortunately.

First of all, there are things that put out fields and that can both attract and repel one another. They're called "magnets." Even though magnets aren't that similar to gravity in some ways, they're still probably the closest tangible real-life example to what you're thinking of. You seem to be implying that magnets are also a source of infinite energy; if you could prove that, please send your proof to me. I'll give you $20 after I take over the world. (The point I'm trying to make here is that any system that has even a trace of friction or other forces acting on it can't be a perpetual-motion machine, regardless of what fields and particles and such you're using. Sorry.)

Could an object with "negative mass" be an easy way of getting into space? Sure! Would it respond to other forces, too? I would think so. Generally, most things in the universe do. I don't know for sure, because I haven't seen one of these negative-mass particles, but it's a general rule that if you put a force on a thing, it will respond to the force. This is the case even with some "massless" particles, such as photons. You seem to be relying on F=ma, but that breaks down when you get to exotic particles at very small sizes, which is the field we're discussing here. Speaking of which!

So let's say we're merrily smashing particles in the LHC tomorrow and somehow find a negative-mass particle. After all of the hoopla and rejoicing, what would we actually do with it? Even if such a particle is stable (and it may not be), you would either have to find a place in the universe where they exist, or you'd have to manufacture about 10^23 of them to lift anything of a particularly impressive size. Maybe more, maybe less: atoms are somewhat heavy, and there's no reason to assume that your negative mass would be particularly insistent at getting away from gravitational fields. There's no reason to assume that the particles could make a solid: there's a significant chance they really don't like one another and it's impossible to get them close enough together to do anything useful. Maybe they bond incredibly readily and a pinpoint-sized amount of negative gravity would be impossible to be contained, drilling a hole up through any container you try to keep it in. Maybe the stuff is a bit like neutrinos, passing through ordinary matter without any problems whatsoever. There's actually an incredibly limited amount of particles that are useful in our universe, so it's more than reasonable to assume negative mass wouldn't be one of them.

Finally, just because something could exist doesn't mean it does. You're making conjectures about things that, for all intents and purposes, are purely imaginary. (A unicorn that can fly is surprisingly consistent with the rules of biology and evolution, and yet, no flying unicorns.)

tl;dr: Neat idea. I think both of your poll answers probably aren't true. Give this whole matter some thought.

-Upsilon

Edited January 26, 2016 by UpsilonAerospace

[hugix]

Negative mass exists, I have proven this in several of our local supermarkets. 

 

You know these scales in the fruit / vegetables departments in supermarkets where you can weigh your groceries? Apparently when you push on the scale from the bottom up some scales give negative weights. Thus proving negative masks, albeit in certain supermarkets. 

[Rdivine]

46 minutes ago, UpsilonAerospace said:

There are a few problems with your logic, unfortunately.

First of all, there are things that put out fields and that can both attract and repel one another. They're called "magnets." Even though magnets aren't that similar to gravity in some ways, they're still probably the closest tangible real-life example to what you're thinking of. You seem to be implying that magnets are also a source of infinite energy; if you could prove that, please send your proof to me. I'll give you $20 after I take over the world. (The point I'm trying to make here is that any system that has even a trace of friction or other forces acting on it can't be a perpetual-motion machine, regardless of what fields and particles and such you're using. Sorry.)

Could an object with "negative mass" be an easy way of getting into space? Sure! Would it respond to other forces, too? I would think so. Generally, most things in the universe do. I don't know for sure, because I haven't seen one of these negative-mass particles, but it's a general rule that if you put a force on a thing, it will respond to the force. This is the case even with some "massless" particles, such as photons. You seem to be relying on F=ma, but that breaks down when you get to exotic particles at very small sizes, which is the field we're discussing here. Speaking of which!

So let's say we're merrily smashing particles in the LHC tomorrow and somehow find a negative-mass particle. After all of the hoopla and rejoicing, what would we actually do with it? Even if such a particle is stable (and it may not be), you would either have to find a place in the universe where they exist, or you'd have to manufacture about 10^23 of them to lift anything of a particularly impressive size. Maybe more, maybe less: atoms are somewhat heavy, and there's no reason to assume that your negative mass would be particularly insistent at getting away from gravitational fields. There's no reason to assume that the particles could make a solid: there's a significant chance they really don't like one another and it's impossible to get them close enough together to do anything useful. Maybe they bond incredibly readily and a pinpoint-sized amount of negative gravity would be impossible to be contained, drilling a hole up through any container you try to keep it in. Maybe the stuff is a bit like neutrinos, passing through ordinary matter without any problems whatsoever. There's actually an incredibly limited amount of particles that are useful in our universe, so it's more than reasonable to assume negative mass wouldn't be one of them.

-Upsilon

Particles with negative mass do not fit inside the analog of magnets, unfortunately. Negative mass particles accelerate in the direction opposite to applied force, hence effectively cancelling the force out altogether. This implies that a particle with negative mass cannot be moved by normal action-reaction forces, hence you might be able to achieve infinite energy by harnessing its lack of reaction to ordinary forces.

Additionally, negative mass particles would respond to gravity and other fundamental forces, but the situation i set up was under an ideal situation with no gravity or other interfering forces. Plus, as long as the concept is there, it is theoretically possible to actually build an object with negative mass, given enough time, or a huge leap in technology.

Now, all this is made under the assumption of the existence of an exotic matter only with negative mass changed relative to it's "normal" counterpart. Hence, the focus on this thread is on negative mass itself, not the particles  

Oh, and a better analog would be ; A unicorn that can fly is consistent with the rules of biology and evolution, but we don't have the capabilities to breed one yet  

Now, don't i have a point here?

 

I'll... I'll show myself out.

[K^2]

Both statements are completely wrong. You cannot use Newtonian physics to properly describe objects of negative mass, but it does not mean that we do not have adequate description of these. Objects of negative mass (e.g. virtual particles,) are commonplace in field theory.

Also, having people vote on something that's common knowledge in theoretical physics is kind of like having a vote on whether or not gravity works. A little silly.

[KSK]

My vote - both your statements are wrong.

The current mathematics regarding the conservation of momentum or energy is correct and complete because you've just used it to deduce the properties of your negative mass particles, should they exist. The fact that we haven't observed a macroscale particle with negative mass doesn't necessarily say anything about the completeness (or otherwise) of our understanding of conservation laws.

Therefore statement 2 is wrong.

Whether or not negative mass is possible, it won't lead to either unstoppable objects or infinite energy. Arguing by Wikipedia:

"Although no particles are known to have negative mass, physicists (primarily Hermann Bondi in 1957,^[3] William B. Bonnor in 1989,^[9] then Robert L. Forward^[10]) have been able to describe some of the anticipated properties such particles may have. Assuming that all three concepts of mass are equivalent the gravitational interactions between masses of arbitrary sign can be explored, based on the Einstein field equations:

• Positive mass attracts both other positive masses and negative masses.
• Negative mass repels both other negative masses and positive masses.

For two positive masses, nothing changes and there is a gravitational pull on each other causing an attraction. Two negative masses would repel because of their negative inertial masses. For different signs however, there is a push that repels the positive mass from the negative mass, and a pull that attracts the negative mass towards the positive one at the same time.

Hence Bondi pointed out that two objects of equal and opposite mass would produce a constant acceleration of the system towards the positive-mass object,^[3] an effect called "runaway motion" by Bonnor who disregarded its physical existence, stating:

“	I regard the runaway (or self-accelerating) motion […] so preposterous that I prefer to rule it out by supposing that inertial mass is all positive or all negative.	”
— William B. Bonnor, in Negative mass in general relativity.[9]

Such a couple of objects would accelerate without limit (except relativistic one); however, the total mass, momentum and energy of the system would remain 0.

This behavior is completely inconsistent with a common-sense approach and the expected behaviour of 'normal' matter; but is completely mathematically consistent and introduces no violation of conservation of momentum or energy."

 

Emphasis added. I think that disposes of the notion of infinite energy. Constant acceleration (hence unstoppable objects) assumes that the objects are only interacting via gravity. However they can be stopped by employing other forces, for example electromagnetism.

More simply, if we have two such bodies travelling through space, they can also be stopped by putting something very large in their path - which statistically, will happen eventually. If the unstoppable objects were travelling at sufficient velocity, any repulsive force exerted on them by said large body would not be enough to appreciably slow them before impact. At which point you have a pair of objects travelling at possibly relativistic speeds and colliding with something. Whatever is left after that is entirely open to speculation but the original objects have most certainly been stopped.

 

Therefore statement 1 is also wrong.

 

 

 

 

[cantab]

Yeah. A negative mass object might react counter-intuitively to an applied force, but it's still perfectly possible for forces to control it.

[YNM]

There's certainly not enough evidence. There's no way to jump the horses yet, nor not to keep on it either. Until they appear commonly, it's still an open question.

Edited January 27, 2016 by YNM

[PB666]

12 hours ago, Rdivine said:

Is it possible to have an object made out of exotic matter which demonstrates properties of negative mass?

A particle of negative mass would accelerate in the direction opposite of applied force, thus pushing an object with negative mass would be impossible, as it would just accelerate in the direction opposite of the push, cancelling out your push force in the first place. This would allow for intergalactic train tracks, where vessels use wheels to push against rails of matter with negative mass, and perhaps infinite energy.

(Infinite energy can be created by , let's say, attaching a very long elastic band to two hooks made of negative mass moving away from each other, and harnessing the elastic potential energy.)

The velocity of a negative mass object can be determined by the initial velocity when it is synthesized, and it would also create more paradoxes. For example, what would happen if two cubes made of negative mass collided with each other? Since their motion cannot be changed by an external force, they are essentially unstoppable. Hence, would the cubes pass right through each other?

All these possibilities sound very cool, and despite being inconsistent with the expected behavior of "normal" matter, negative mass is mathematically consistent and introduces no violation of conservation of momentum or energy.

Now, only one of the statements below are true.

1. Negative mass is possible, allowing for unstoppable objects and (perhaps) infinite energy.

2. The current mathematics regarding the conservation of momentum or energy is incorrect/incomplete.

You can vote on which statement you would think is true in the polls above! Meanwhile, share your opinions below!.

 

false dicotomy, ignored

[Shpaget]

12 hours ago, hugix said:

Negative mass exists, I have proven this in several of our local supermarkets. 

 

You know these scales in the fruit / vegetables departments in supermarkets where you can weigh your groceries? Apparently when you push on the scale from the bottom up some scales give negative weights. Thus proving negative masks, albeit in certain supermarkets. 

That would be negative weight, not negative mass. Weight is a vector where the minus sign only means it's acting in the opposite direction of the, in this case, "down".

There is no object in your supermarket that will drive a zeroed scale into the negatives when placed on that scale.

[hugix]

I am currently working on a new experiment involving helium ballons and tape. 

 

Okay, I'm done now

Edited January 27, 2016 by hugix

[Darnok]

Mass is human invention, it is part of model created by Newton.

Mass and all calculation with "weird" numbers just fits best to explain force that appears between object and Earth, but that doesn't means mass really exists.

Edited January 27, 2016 by Darnok

[kerbiloid]

All except natural numbers can be negative.

[Darnok]

19 hours ago, UpsilonAerospace said:

 You seem to be implying that magnets are also a source of infinite energy; if you could prove that, please send your proof to me. I'll give you $20 after I take over the world. (The point I'm trying to make here is that any system that has even a trace of friction or other forces acting on it can't be a perpetual-motion machine, regardless of what fields and particles and such you're using. Sorry.)

Creating coal costs energy, we can build device that will drain energy from coal... of course as result (output) we can get only fraction of energy that was used to create coal.

This should work with any element...

Creating magnets costs energy... so why do most people think we can't build device that would drain energy from magnets? This is same case as with coal, you should expect in output only fraction of energy used to create this magnet.

How this breaks conservation of energy?

[peadar1987]

11 hours ago, Shpaget said:

That would be negative weight, not negative mass. Weight is a vector where the minus sign only means it's acting in the opposite direction of the, in this case, "down".

There is no object in your supermarket that will drive a zeroed scale into the negatives when placed on that scale.

Helium balloons and sticky tape

[Shpaget]

Try it in vacuum.

[peadar1987]

56 minutes ago, Shpaget said:

Try it in vacuum.

My local supermarket is not a vacuum

[Rdivine]

57 minutes ago, Shpaget said:

Try it in vacuum.

I'm pretty sure the original post was meant to be a joke mocking the silly properties of weighing machines

More to the point, negative mass would respond opposite to gravity, this it is repelled away from normal matter. However, when both negative masses encounter each other, they would demonstrate normal gravitational forces on each other (like how two negatives form one positive).

[peadar1987]

3 minutes ago, Rdivine said:

I'm pretty sure the original post was meant to be a joke mocking the silly properties of weighing machines

More to the point, negative mass would respond opposite to gravity, this it is repelled away from normal matter. However, when both negative masses encounter each other, they would demonstrate normal gravitational forces on each other (like how two negatives form one positive).

This link gives a bit of an explanation, which seems to be essentially "we don't really know": http://www.physicscentral.com/experiment/askaphysicist/physics-answer.cfm?uid=20140818013234

[K^2]

17 minutes ago, peadar1987 said:

My local supermarket is not a vacuum

It'd be bad for business, yes.

But yeah, distinguishing between effective weight and mass is kind of important. Although, an effect similar to buoyancy may exist for mass. Casimir Effect comes to mind.

[magnemoe]

29 minutes ago, Rdivine said:

I'm pretty sure the original post was meant to be a joke mocking the silly properties of weighing machines

More to the point, negative mass would respond opposite to gravity, this it is repelled away from normal matter. However, when both negative masses encounter each other, they would demonstrate normal gravitational forces on each other (like how two negatives form one positive).

Yes, note that having a lot of knowlege about the theory regarding negative mass is probably more useful than helium ballons if you are caught manipulation their weights. 
Note that this also require that you are very good at talking people around had been better off selling stuff than messing with weights
More fun is to get the weight to print an negative number and demand to get money back

More seriously weights has negative numbers as you can subtract the weight of the container. This is very useful on kitchen scales. Yes you can even do it with containers with content then adding more stuff. 
 

[cantab]

4 hours ago, Rdivine said:

More to the point, negative mass would respond opposite to gravity, this it is repelled away from normal matter. However, when both negative masses encounter each other, they would demonstrate normal gravitational forces on each other (like how two negatives form one positive).

You've got that wrong actually. If you consider the gravitational force experienced by a negative gravitational mass near the Earth, the force is away from the Earth. But a negative inertial mass accelerates in the opposite direction to the applied force, so it is still attracted to the Earth. The force exerted on the Earth by the negative gravitational mass is away from the negative mass, and Earth being plain old positive mass it therefore accelerates away.

In terms of fields, the gravitational field of a positive mass accelerates all masses towards it, while the gravitational field of a negative mass accelerates all masses away from it.

This is natural when you consider the general relativistic perspective of gravity as the deformation of spacetime.

On a related note, it has occurred to me before that electromagnetism would misbehave with negative masses. Instead of like charges repelling, they would effectively attract, and unlike charges repel. If charged negative mass particles exist they would segregate themselves by charge, which would probably have dramatic effects. Indeed I suspect they'd form a sort of electromagnetic black hole - a sufficient charge in a small enough space that other charged particles either cannot escape or cannot enter.

But then said hole would capture opposite-charged positive-mass particles, reducing both its overall mass and overall charge.

I wonder if this couldn't account for the non-observability of negative mass? That a negative mass electron, say, would encounter a positive mass positron and then what? You've got zero mass, zero charge - isn't that just nothing? A kind of annihilation more complete than that between matter and antimatter. Perhaps leaving a photon if there is leftover net momentum.

Edited January 27, 2016 by cantab