Does Negative Mass Exist in the Universe?

[superweirdo]

does negative mass exists?

 

[Gelsamel Epsilon]

http://en.wikipedia.org/wiki/Negative_mass#Negative_mass

 

[superweirdo]

it says it hasn't been proven if it is exist however, by mathematics, it is supposed to react just like electromagnetism except that like masses would attract and opposite would repel. Now, does anybody think he can explain the exception?

 

[actionintegral]

An antiparticle would have a negative rest mass

 

[Norman]

An antiparticle would have a negative rest mass

Ah... any proof for that? Antiparticles do not have negative rest mass.

 

[superweirdo]

So is that it, there are no more theories on negative mass?

 

[actionintegral]

According to the feynman's theory of positrons, the proper time for an antiparticle the reverse of the proper time for matter. The proper mass would be reversed as well. All invariant quantities would be reversed for
antiparticles.

 

[superweirdo]

but we aren't sure that antiparticle exists either. As far as I know, the only reason we even believe in antiparticles is b/c of them, we laws make sense b/c when you exclude them from theory, our physics seems flawed, still a lot of physicist don't believe in it though coz we don't have a brute evidence for it.

 

[selfAdjoint]

but we aren't sure that antiparticle exists either. As far as I know, the only reason we even believe in antiparticles is b/c of them, we laws make sense b/c when you exclude them from theory, our physics seems flawed, still a lot of physicist don't believe in it though coz we don't have a brute evidence for it.

Boy, if the antiproton doesn't exist, the Tevatron physicists must have made up all of that data they've published. You think?

 

[Mk]

but we aren't sure that antiparticle exists either. As far as I know, the only reason we even believe in antiparticles is b/c of them, we laws make sense b/c when you exclude them from theory, our physics seems flawed, still a lot of physicist don't believe in it though coz we don't have a brute evidence for it.

We are sure they exist. CERN even has an antimatter factory. :!)

 

[Norman]

According to the feynman's theory of positrons, the proper time for an antiparticle the reverse of the proper time for matter. The proper mass would be reversed as well. All invariant quantities would be reversed for
antiparticles.

Only reversed in time. It has the same mass. Check out the http://pdg.lbl.gov" .

 

[actionintegral]

Hi Norman,
Sorry to appear obtuse, but once I learned that antiparticles were reversed in time, I jumped to the conclusion that all invariant quantities were reversed for antiparticles. Please follow me to the QM forum where I
re-posed my question.

 

[selfAdjoint]

Hi Norman,
Sorry to appear obtuse, but once I learned that antiparticles were reversed in time, I jumped to the conclusion that all invariant quantities were reversed for antiparticles. Please follow me to the QM forum where I
re-posed my question.

Try googling on CPT Theorem.

 

[actionintegral]

I'll check it out - Thanks!

 

[superweirdo]

I didnt even know that antiproton exist, I guess I shouldn't argue you guys about these things, so far, I am only aware of 3 anti things, antimatter, antiparticle, and anti proton. Are there anymore?

 

[selfAdjoint]

I didnt even know that antiproton exist, I guess I shouldn't argue you guys about these things, so far, I am only aware of 3 anti things, antimatter, antiparticle, and anti proton. Are there anymore?

Antimatter is the collective name for the antiparticles. The modern way of looking at it is, every particle has a corresponding antiparticle, but sometimes the particle is its own antiparticle. This is like saying every quadratic equation has two solutions, but sometime the solutions coincide; it's perhaps just a manner of speaking but it makes thinking about antiparticles a little smoother.

So all the particles in the standard model come with antiparticles. That's six quarks, six leptons, four electroweak bosons (including the photon) and eight QCD bosons, the gluons. Therefore all those numbers I gave except one should be doubled. The one exception is the four electroweak bosons. It is required that an antiparticle have opposite charge to its particle; so for example the electron is electrically negative and therefore the positron (as the antielectron is called for historic reasons) has to be electrically positive.

The electroweak bosons consist of the photon, which is electrically neutral, the W⁺ and W^- particles, which are each other's antiparticle (guess which one is positive and which one negative), and the Z⁰ particle, which is also electrically neutral. Since they have no charge to reverse, the photon and the Z⁰ are their own antiparticles.

The point about charge reversal applies not only to the familiar electrical charge, but to the triple "color charge" of QCD; each of its three varieties comes in a "positive and negative" form (the "negative" one is called an anticharge), and the gluons which are elctrically neutral each carry a pair, consisting of one of the three color charges and one of the three anticharges, but not the anticharge of its charge. And that gluon's antigluon carries the opposite one of each of that pair. So if they meet and annihilate, the total QCD charge of the event comes out to zero, as it should.

 

[chroot]

Every known particle has an antiparticle.

- Warren

 

[superweirdo]

What you said completely made sense to me selfadjoint but the analogy you gave didn't sound right to me, rather I'd like to use the analogy that every equation has an inverse but for the equation that don't, here though, their inverse is the same equation.(this isn't mathematically correct but seems more logical to me)

btw, I also heard something about antiparticles that they have inverse time and space(guessing this one) too which didn't make sense to me, could you guys explain this to me?

 

[selfAdjoint]

What you said completely made sense to me selfadjoint but the analogy you gave didn't sound right to me, rather I'd like to use the analogy that every equation has an inverse but for the equation that don't, here though, their inverse is the same equation.(this isn't mathematically correct but seems more logical to me)

You are driving the analogy too hard. I wasn't trying to model antimatter in high school algebra, just the community habit of treating the exceptional case as a normal case with an asterisk.

btw, I also heard something about antiparticles that they have inverse time and space(guessing this one) too which didn't make sense to me, could you guys explain this to me?

In the math, you can do a transformation t -> -t and that transforms the expression for a particle into one for its antiparticle. People with gee-whiz aspirations can read into that whatever they like but it's emphatically just a symmetry of the math, not a fact of nature.

 

[superweirdo]

so you don't believe that it have has inverse time and maybe space?

 

[actionintegral]

yes. anti-perspirant.

 

[Gokul43201]

so you don't believe that it have has inverse time and maybe space?

Being meaningless, that's a question that can not be answered.

 

[superweirdo]

I am not sure if I follow your metaphor Gokul.

 

[selfAdjoint]

I am not sure if I follow your metaphor Gokul.

He means your statement

"so you don't believe that it have has inverse time and maybe space?"

has no semanttic content that anyone else can detect. Consider recasting it.

 

[pallidin]

I would offer to superweirdo: Please do not be confused with the term "anti"
An anti-particle is only "anti" in certain respects, NOT ALL RESPECTS. For example, a positron(which is an anti-electron) has opposite charge but the exact same mass, and that mass is not "negative mass"; its just the same, regular type of mass. Just the charge is "anti"

Anti-matter DOES NOT mean or infer anti-mass in any respect. As such, there is no "anti-time" or "anti-space" associated with anti-particles.

 

[Gokul43201]

Sadly, the most commonly observed occurance of a "negative mass", the effective mass of charge carriers in a crystal, has gone unmentioned.

 

[actionintegral]

There is an old paper by Bondi about negative mass. Since I only have negative money, can someone send it to me?

 

[ZapperZ]

Sadly, the most commonly observed occurance of a "negative mass", the effective mass of charge carriers in a crystal, has gone unmentioned.

I was waiting to see how long before someone would say something about this, Gokul. I suppose if isn't from one of us, no one would even be aware of such a thing existing in other parts of physics.

Zz.

 

[kmarinas86]

Being meaningless, that's a question that can not be answered.

1/s = frequency
1/m^3 = ?

 

[pmb_phy]

There is an old paper by Bondi about negative mass. Since I only have negative money, can someone send it to me?

Sure. See

www.geocities.com/physics_world/gr/bondi_1957.pdf

Pete

 

[Rade]

A recent paper that "suggests" possibility of negative mass--someone needs to verify the math:
http://www.ptep-online.com/index_files/2006/PP-06-09.PDF

 

[jhmar]

Do not loose track of reality. According to David Gross (Nobel Luareate) We are in a state of confussion...these equations tell us nothing about where space and time come from and describe nothing we would recognize. We are missing something fundamental.
What we know is a collection of mathematical short cuts which predict. we know not why or how.

 

[ZapperZ]

A recent paper that "suggests" possibility of negative mass--someone needs to verify the math:
http://www.ptep-online.com/index_files/2006/PP-06-09.PDF

Please note that this is not considered as a mainstream journal (I don't even know anyone who cites this thing). I strongly suggest from now on that this source is not used.

Zz.

 

[PrinceOfDarkness]

What about the 'negative energy' solutions of Dirac's equation? Doesn't negative energy suggest negative mass?
In my QM course, my Prof. taught us repeatedly energy can't be negative. But then I was hearing this discussion about how Dirac proposed the existence of positrons and I was confused. Can somebody explain what happens to those 'negative energy' solutions?

 

[fedorfan]

When you say negative mass, what exactly is different from normal mass and negative? Is negative mass a whole lot smaller than positive mass? What exactly is it?

 

[fedorfan]

Why is it called negative mass? I am thinking normally about it, like the mass actually is twice as small. Is this right? What is it?

 

[Rade]

Why is it called negative mass? I am thinking normally about it, like the mass actually is twice as small. Is this right? What is it?

No, the mass is not twice as small--see this link: http://www.concentric.net/~pvb/negmass.html

 

[Rade]

Please note that this is not considered as a mainstream journal (I don't even know anyone who cites this thing). I strongly suggest from now on that this source is not used.Zz.

OK, will do. But, has anyone checked the math ? Is not good math in bad journal = good science ?

 

[fedorfan]

I see what youre saying now, I was thinking like it was made of twice as less matter than positive mass. Dumb me. Thanks

 

[Andrew Mason]

http://en.wikipedia.org/wiki/Negative_mass#Negative_mass

It think this Wikipedia article has it wrong. It says:

"However, particle/antiparticle pairs are observed to electrically attract one another, often as the prelude to annihilation. This behavior implies that both have positive inertial mass and opposite charges. If the reverse were true, and antiparticles had negative inertial mass and the same charge, then the normal particle with positive inertial mass would still be repelled by its anti-particle."​

If the anti-particle has negative mass it has negative inertia so it moves opposite to the direction of the force. Thus, if the force is away from the normal particle (if the particle and anti-particle had the same charge) the anti-particle would accelerate toward the normal particle. So the result is the same as if they had opposite charges and both had positive mass.

AM

 

[Farsight]

Would they both fall down, Andrew? And would they both skitter away if I kicked them? If so it doesn't really sound like negative mass.

The only genuine negative mass I can think of is a hole. I take a rather topological view of particles, so I don't see a hole as something to be discounted. Can anybody comment on this? It seems reasonable, for example in this here paper concerning holes and superconductors:

http://arxiv.org/ftp/cond-mat/papers/0503/0503368.pdf

"The remaining hole is commonly defined as having a positive mass and charge, to avoid
complications of describing transport in terms of negative masses..."

 

[TopcatBV]

And what about the evaporation of the black holes?
Doesnt Hawkins mention very briefly about the particle with negative mass who falls in the black hole and anihilate with a normal particle? I didnt heard Hawkins saying that the particle inside the black hole anihilate with the antiparticle who fall in it and generate photons. They are vanishing, evaporating the black hole through the remaining pair-particle, no?

 

[Andrew Mason]

A recent paper that "suggests" possibility of negative mass--someone needs to verify the math:
http://www.ptep-online.com/index_files/2006/PP-06-09.PDF

Please note that this is not considered as a mainstream journal (I don't even know anyone who cites this thing). I strongly suggest from now on that this source is not used.

Zz.

Here is an http://en.wikipedia.org/wiki/Florentin_Smarandache" about the Florentin Smarandache, author of this article and the founder of this journal, PROGRESS IN PHYSICS. Definitely not mainstream, the article refers to it as a 'crank' journal. Smarandache is a professor of mathematics at University of New Mexico. I wonder what Murray Gellmann, who is also at UNM, thinks of this guy's physics...

AM

 

[Hans de Vries]

It think this Wikipedia article has it wrong. It says:

"However, particle/antiparticle pairs are observed to electrically attract one another, often as the prelude to annihilation. This behavior implies that both have positive inertial mass and opposite charges. If the reverse were true, and antiparticles had negative inertial mass and the same charge, then the normal particle with positive inertial mass would still be repelled by its anti-particle."​

If the anti-particle has negative mass it has negative inertia so it moves opposite to the direction of the force. Thus, if the force is away from the normal particle (if the particle and anti-particle had the same charge) the anti-particle would accelerate toward the normal particle. So the result is the same as if they had opposite charges and both had positive mass.

AM

The article is correct though, You are right about the anti-particle's
behavior but the statement they make is about the normal particle.



Regards, Hans

 

[Hans de Vries]

Would they both fall down, Andrew? And would they both skitter away if I kicked them? If so it doesn't really sound like negative mass.

Negative mass particles would behave the same in a gravitational field if
both their inertial and gravitational mass are negative. It just an extension
of Galileo’s observation that the acceleration of objects doesn't depend
on their mass.

The reaction on kicking them would also be the same if the actual Force
is electrostatic, however the reaction of the normal particles would
reveal them as "negative mass, same charge" as the Wikipedia article
mentions.Regards, Hans

 

[Andrew Mason]

The article is correct though, You are right about the anti-particle's
behavior but the statement they make is about the normal particle.

Ok. The normal particle is repelled by the negative mass so it will accelerate away from it, while the negative mass accelerates toward the positive mass. But this does not mean that the separation would always increase if one of the masses is negative, which is what the article seems to say.

If they have masses of equal magnitude (opposite direction), whether the separation increases or decreases depends on which is initially approaching/moving away faster. Slight differences in initial kinetic energy will determine whether they approach or separate. It's like a wolf chasing a deer. Slight differences in initial kinetic energy make all the difference.

AM

 

[Farsight]

The normal particle is repelled by the negative mass so it will accelerate away from it, while the negative mass accelerates toward the positive mass.

That doesn't sound right Andy. Did I misunderstand, or will these two masses accelerate away forever?

It just an extension of Galileo’s observation that the acceleration of objects doesn't depend on their mass.

Thanks Hans. Now that is really interesting.

 

[rbj]

The normal particle is repelled by the negative mass so it will accelerate away from it, while the negative mass accelerates toward the positive mass.

That doesn't sound right Andy. Did I misunderstand, or will these two masses accelerate away forever?

It just an extension of Galileo’s observation that the acceleration of objects doesn't depend on their mass.

Thanks Hans. Now that is really interesting.

take a look at the other thread, guys (in the Classical phyisics forum). this was the observation 3 or 4 days ago.

in my opinion (but since I'm just an EE, i will also say the opinion of a couple of heavyweights on sci.physics.research) is that the consequences of this observation bodes very poorly for the reality of negative mass. if you can construct two blobs of equal mass except one blob negative and the other blob positive, you can make yourself a perpetual motion machine or a space drive mechanism that you don't have to feed fuel or propellent into (not sure how you would turn it on or off).

 

[Farsight]

Thanks rbj. It rather makes me think negative mass makes as much sense as negative red. There seem to be a lot of threads on it at the moment.

 

[TopcatBV]

So, in the Hawkins radiation explanation is envolved negative mass or I misunderstood somethink?