# A question about anti matter

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I know that most scientists think that matter and anti matter will be affected by gravity the same, there are some that are holding out for anti matter to have anti gravity effects when it comes close to matter.

If ( I KNOW HUGE WORD) but if this turns out to be true wouldn't this mean that anti gravity and matter would be attracted to each other twice as much as any two chunks of either would be attracted?

In positive and negative charges they are usually attracted to each other but wouldn't that mean that positive and negative gravity would attract each other?

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I know that most scientists think that matter and anti matter will be affected by gravity the same, there are some that are holding out for anti matter to have anti gravity effects when it comes close to matter.

If ( I KNOW HUGE WORD) but if this turns out to be true wouldn't this mean that anti gravity and matter would be attracted to each other twice as much as any two chunks of either would be attracted?

In positive and negative charges they are usually attracted to each other but wouldn't that mean that positive and negative gravity would attract each other?

Ignoring for a moment the question of what anti-gravity would even look like, in this analogy, "normal" gravity would be 'positive' and two positive charges repel. Since gravity is an attractive force between chunks of matter and not a repelling force, I don't think you can draw conclusions about the behavior of "positive and negative gravity" from the behavior of charges.
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Antimatter has positive real mass. Who are these scientists "holding out for anti matter to have anti gravity effects when it comes close to matter"? Basically, [citation needed]

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Antimatter has positive real mass. Who are these scientists "holding out for anti matter to have anti gravity effects when it comes close to matter"? Basically, [citation needed]

http://en.wikipedia.org/wiki/Gravitational_interaction_of_antimatter

The gravitational interaction of antimatter with matter or antimatter has not been conclusively observed by physicists. While the overwhelming consensus among physicists is that antimatter will attract both matter and antimatter at the same rate that matter attracts matter, there is a strong desire to confirm this experimentally, since the hypothesis is still open to falsification.

Antimatter's rarity and tendency to annihilate when brought into contact with matter makes its study a technically demanding task. Most methods for the creation of antimatter (specifically antihydrogen) result in high-energy particles and atoms of high kinetic energy, which are unsuitable for gravity-related study. In recent years, first ALPHA [1][2] and then ATRAP [3] have trapped antihydrogen atoms at CERN; in 2013 ALPHA used such atoms to set the first free-fall bounds on the gravitational interaction of antimatter with matter. Future experiments on ALPHA, as well as experiments on beams of antihydrogen by AEGIS and GBAR should refine these bounds.

The CPT theorem asserts that antimatter should attract antimatter in the same way that matter attracts matter.[citation needed] However, there are several hypotheses about how antimatter gravitationally interacts with normal matter:

• Normal gravity: The standard assumption is that gravitational interactions of matter and antimatter are identical.
• Antigravity: Theoretical analysis suggests that antimatter might repel matter with the same magnitude as matter attracts matter.[4][5]

This should not be confused with the many other speculative phenomena that may also be called 'anti-gravity':

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

Although no particles are known to have negative mass, physicists (primarily Hermann Bondi and Robert L. Forward) 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.

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My layman hunch about antimatter is that their domain is space; rarely, in so called hole particles, they have been imprisoned inside common matter. Their constituents exist in non organized and dispersed status unable to create steady common antimatter particles---except in marriage with particles of common mater --- in form of photons.

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"There's absolutely no reason to believe this is wrong (and all evidence points to it being true), but there's never been a direct test, so let's believe it is false" is an exceedingly terrible argument.

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"There's absolutely no reason to believe this is wrong (and all evidence points to it being true), but there's never been a direct test, so let's believe it is false" is an exceedingly terrible argument.

ydoaPs, you misunderstand, I am not suggesting that anti matter is negative mass or gravity, I wanted to know how anti gravity would act if it was true. I was comparing it to positive and negative charges and how opposites attract.

It seems to me as a thought experiment mass with anti gravity would be attracted to normal gravity mass.... not repelled...

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My layman hunch about antimatter is that their domain is space; rarely, in so called hole particles, they have been imprisoned inside common matter. Their constituents exist in non organized and dispersed status unable to create steady common antimatter particles---except in marriage with particles of common mater --- in form of photons. [/size]

do you know what happens when antimatter comes in the vicinity of matter ?

i have to say obviously not.

antimatter is unstable.

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do you know what happens when antimatter comes in the vicinity of matter ?

i have to say obviously not.

antimatter is unstable.

It does not follow from annihilation that antimatter is unstable.

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It does not follow from annihilation that antimatter is unstable.

i have no clue what you mean by follows,

but antimatter is unstable.

do you even know what it takes to store/contain it ?

edit-

it's so unstable,

antimatter has to be stored in a vacuum and kept away from a container's walls by powerful magnets.

Edited by krash661
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i have no clue what you mean by follows,

but antimatter is unstable.

do you even know what it takes to store/contain it ?

Magnetic fields and/or antimatter containers. If you somehow derive instability from annihilation, why anti-matter instead of matter? By your reasoning, you just as easily conclude that matter is "unstable".

If we drop a few particles of matter in a part of the universe dominated by antimatter, what could store/contain it?

it's so unstable,

antimatter has to be stored in a vacuum and kept away from a container's walls by powerful magnets.

The same could be said of matter if the container was made of anti-matter.

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i'm not going to sit here and argue with you,

all i can say is learn about antimatter.

edit-

i went through it,

everything you need is there,

just make sure you understand it.

Edited by krash661
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i'm not going to sit here and argue with you,

all i can say is learn about antimatter.

That's a brilliant strategy. If you can't support what you say, simply tell someone to go learn something. It reminds me of the time someone told swansont that he needed to go research atomic clocks.

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simply tell someone to go learn something.

majority of staff on this site is immature in knowledge.

That's a brilliant strategy. If you can't support what you say,

recheck that post of mine, because i made an edit for your

" That's a brilliant strategy. If you can't support what you say, "..

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Krash, I read your link a couple of times and I couldn't find where it states that anti matter is unstable, Can you quote where it says that please?

Maybe I shouldn't have said anti matter, I was thinking more along the lines of anti mass and anti gravity. I know that gravitational effects of anti matter is expected to be the same as matter but there are a few hypothesis that disagree and the experiments haven't been done as of now.

Now back to the topic, wouldn't anti gravity require anti mass and would or would not it be attracted to positive gravity or mass?

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Krash, I read your link a couple of times and I couldn't find where it states that anti matter is unstable, Can you quote where it says that please?

Maybe I shouldn't have said anti matter, I was thinking more along the lines of anti mass and anti gravity. I know that gravitational effects of anti matter is expected to be the same as matter but there are a few hypothesis that disagree and the experiments haven't been done as of now.

Now back to the topic, wouldn't anti gravity require anti mass and would or would not it be attracted to positive gravity or mass?

well i have to say, it's not being understood.

but try this one then,

there's a lot of data on this,

you just have to look.

Edited by krash661
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well i have to say, it's not being understood.

but try this one then,

http://www.mcclatchydc.com/2009/03/11/63771/scientists-harness-anti-matter.html#.UfVJ-NLqmJR

there's a lot of data on this,

you just have to look.

Ok, I see what the problem is, anti matter is unstable "in the presence of matter" but no more unstable than "matter in the presence of anti matter", left apart, both are more or less equally stable/unstable...

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Ok, I see what the problem is, anti matter is unstable "in the presence of matter" but no more unstable than "matter in the presence of anti matter", left apart, both are more or less equally stable/unstable...

Indeed, as I've already said. Apparently Krash has a matter bias ior doesn't adequately understand the topic.

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i understand the topic fine,

and lol i'm very qualified,

how many PhD's do you have ?

but you need to know all aspects of it in order to understand this little piece.

simple.

it's a matter of understanding the sources.

did you even read and understand them ?,

i have to say no.

like i said,

i'm not going to sit here and argue with you,

all i can say is learn about antimatter.

Edited by krash661
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Let me see if I understand you correctly, Moontanman.

Antimatter would exhibit antigravity only if it also had the property of antimass. Now since mass is more or less related to energy by Einstein's

M=E/c^2

then antimass or negative mass implies antienergy or negative energy, since c^2 definitely cannot be negative.

This opens up a whole new can of worms. Equal amounts of energy and antienergy ( contained in a proton and antiproton for example ), effectively equal to zero energy, would be able to produce a positive energy gamma emission. Oops there goes one conservation law.

And as far as I know antimatter doesn't have the same properties nor is it equivalent to 'exotic' matter.

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Unstable means it spontaneously decays. That matter and antimatter annihilate says nothing about the stability of either one, since annihilation is an induced reaction.

i'm not going to sit here and argue with you,
all i can say is learn about antimatter.

edit-

http://van.physics.illinois.edu/qa/listing.php?id=1152

i went through it,
everything you need is there,

just make sure you understand it.

I don't think that says what you think it says. It uses unstable three times, and each time it refers to antimatter being unstable if its matter counterpart is unstable.

"Many other kinds of antimatter are unstable because their matter counterparts are unstable too (i.e., they exist for a very tiny fraction of a second before decaying into more usual stuff)"

Or, put another way: if it's unstable, what is the half-life of a positron?

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deleted

Edited by krash661
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ydoaPs, you misunderstand, I am not suggesting that anti matter is negative mass or gravity, I wanted to know how anti gravity would act if it was true. I was comparing it to positive and negative charges and how opposites attract.

It seems to me as a thought experiment mass with anti gravity would be attracted to normal gravity mass.... not repelled...

Again, though, gravity isn't a charge. If opposite gravities attract and like gravities repel, then you'd expect there to be an attractive force between mass and anti-mass and a repulsive force between mass and mass or anti-mass and anti-mass. Since gravity is obviously an attractive force between two points of "positive" mass, the analogy with charge falls apart and there's no reason to expect similar behavior under as yet unobserved circumstances when the currently observable ones show that gravity does not behave like charge in this respect.

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This thread sure has been diverted off-topic. Note to krash: Antimatter is not unstable in and of itself. The problem is that antimatter and ordinary matter are markedly unstable when the two meet.

It's time to go back to the original topic.

I know that most scientists think that matter and anti matter will be affected by gravity the same, there are some that are holding out for anti matter to have anti gravity effects when it comes close to matter.

If ( I KNOW HUGE WORD) but if this turns out to be true wouldn't this mean that anti gravity and matter would be attracted to each other twice as much as any two chunks of either would be attracted?

In positive and negative charges they are usually attracted to each other but wouldn't that mean that positive and negative gravity would attract each other?

The other way around, Moontanman. Physicists know that antimatter has the same inertial mass, including sign, as does ordinary matter. This means that if (and this is a big if) antimatter has negative gravitational mass, it would fall up, not down, due to Earth gravity.

The equivalence principle says that inertial mass and gravitational mass are one and the same (including sign), but just because someone says that this is the case does not mean that it is the case -- even if that someone is Einstein. The equivalence principle has been subjected to a wide variety of tests. It now stands as one of the most precisely verified concepts in physics, but only for ordinary matter.

Testing how antimatter behaves when subjected to gravitation has been highly problematic because of the proclivity of matter and antimatter to annihilate one another. The best results to date are that the gravitational mass of antimatter is somewhere between -65 and +110 times the inertial mass. That's not very good given that the factor is supposed to be exactly one.

These results come from the ALPHA experiment at CERN. This experiment is currently being upgraded specifically for the purpose of studying how antimatter behaves under the influence of gravity. The update should be completed sometime next year, so we can expect results two or three years from now.

Thanks DH...

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