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Xaxafrad t1_iu8426x wrote

Another fun fact: Antimatter costs over $70 trillion per gram.

Now here's a fun question: how long would it take us to produce 1 gram of antimatter at current production levels?

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scurvydog-uldum t1_iu846yt wrote

does antimatter weigh the same as matter, or would that be an antigram?

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Xaxafrad t1_iu84h3j wrote

There's absolutely no difference in mass or gravitational effect.

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scurvydog-uldum t1_iu84l82 wrote

c'mon, work with me here.

how are we supposed to get anti-gravity generators if antimatter has positive gravitational effect?

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onewobblywheel t1_iu8yfgd wrote

Source?

I don't believe anyone had proven that. It's an open question.

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SoItWasYouAllAlong t1_iu9znvn wrote

For a source, you can try: Wikipedia -> positron -> mass.

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onewobblywheel t1_iub1huy wrote

Mass and weight are different things. Mass relates to inertia, not necessarily gravity. (things can have the same mass on Earth and the Moon and Mars, but weight different amounts on all three planets -- yes, planets.)

To the best of my knowledge, no one has measured how antimatter is affected by gravity. No one has made enough of it to do that. It's still an open question.

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SoItWasYouAllAlong t1_iub4ne7 wrote

>Mass relates to inertia, not necessarily gravity.

Where are you getting this? No experiment has ever unambiguously demonstrated any difference between inertial and gravitational mass. This of course doesn't say much about antimatter, which has not been experimentally covered wrt gravity.

But anyhow, on your main point - my understanding is the same. Until someone actually measures antimatter's reaction to gravity, it's anybody's guess. IIUC, we have a good model for the makeup of antimatter of quarks, but that doesn't suffice, since we don't have a quantum model of gravity.

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onewobblywheel t1_iubeiee wrote

>No experiment has ever unambiguously demonstrated any difference between inertial and gravitational mass

You're confused. Inertia and gravity are fundamentally different things,

mass is a property of a thing that causes it to resist changes in velocity.

Gravity is the interaction of two things, currently assumed to be the result of their warping of space-time.

Matter and Antimatter can have the same mass and same inertia, but what if antimatter warps space-time in the opposite direction of regular matter? Instead of a dimple, it makes a bump ???

No one knows.

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Mystiic_Madness t1_iub27d3 wrote

Current production rate is like 10 nanograms per 20 years.

The problem is storing it though since all of that antimatter was annihilated after it was produced.

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Xaxafrad t1_iuc6rye wrote

So 2 billion years, assuming we solve the storage problem. Well, now I know that.

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scurvydog-uldum t1_iu8450k wrote

hol up.

if neutrons have a neutral charge and antineutrons also have a neutral charge...

what's anti about it?

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Xaxafrad t1_iu84ot1 wrote

Their quark composition. An up and two downs, vs an anti-up and two anti-downs. In both cases, their fractional electric charges cancel out.

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AirborneRodent t1_iu850s6 wrote

You have to go smaller. A neutron is made of an up quark (+2/3 charge) and two down quarks (-1/3 charge each). An antineutron is made of an up antiquark (-2/3 charge) and two down antiquarks (+1/3 charge each).

Even though they both sum to zero charge, they're still opposite. And they still annihilate each other if they come in contact.

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onewobblywheel t1_iu8z5d1 wrote

Get ready for a mind-blow...

Physicist Richard Feynman successfully modeled antimatter as ordinary matter that moves backwards through time.

A lot of modern physicists disagree, but Feynman is considered the closest thing to a new Einstein as there is (other than, potentially, Hawkins.)

Look up the X and Y axes of Feynman Diagrams (space and time) and the direction of the particles they model.

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svladcjelli42 t1_iu9p3s6 wrote

It is now generally accepted that Feynman is correct about that, in the sense that reversing charge and parity is indistinguishable from reversing direction in time. It's one or the other, but there isn't really a difference.

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AkshuallyGuy t1_iu936x5 wrote

>Physicist Richard Feynman successfully modeled antimatter as ordinary matter that moves backwards through time.

Hmm, what if I just changed the signs on everything...

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Slartibartfast39 t1_iu84jvy wrote

I seem to remember being taught that there should be equal amounts of matter and anti matter in the universe but there isn't. As when they meet both undergo annihilation the possibility is that this occurred early on in the universe and there was an excess of matter over antimatter. I was taught that were not sure why.

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Shadowkiller00 t1_iu850n3 wrote

Yes, this and the difference in the amount of matter and antimatter was just the tiniest fraction of a percent, but that tiny fraction difference is enough to leave behind all the matter that exists in the universe.

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ladan2189 t1_iu8xpfp wrote

As the current theory says. The current theory also says that there should be massive amounts of dark matter and dark energy in the universe but we can't detect it anywhere. There's always a chance that the theory is wrong. It's what happens when your whiteboard physics can't be disproven but there's no evidence to support it either.

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Joeclu t1_iu845w0 wrote

But are there anti-quarks that make the anti-proton?

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Soyoulikedonutseh t1_iu8msy8 wrote

I've never heard this before? Is this just a theory?

Last time I checked, they don't really know what antimatter is. Infact, the term antimatter is miss leading because frankly, they don't even know if it's matter

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bearsnchairs t1_iu8xtbu wrote

Are you mixing up anti matter with dark matter? Anti matter is very much real. We make it in labs all the time. It is produced in radioactive decay and by cosmic ray collisions.

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ZhouDa t1_iu8vygo wrote

No, it's very real and they can even make small amounts of antimatter and store it if they contain it in a magnetic field since contact with matter turns it all into energy. Whenever they hit a couple particles with a super-collider some of it will be antimatter. The only mystery is why the universe turned out to be made of matter which suggests matter might be more stable or created more often somehow.

Edit: Also a theory means something different to scientists and the way people use it in everyday speech would really mean a hypothesis.

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ebeth_the_mighty t1_iu9h258 wrote

I did a science project on antimatter in grade 9. That was 1985. Just saying.

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DraslinHDF t1_iu9n3lr wrote

It always struck me as odd that antineutrons need to exist.

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ElfMage83 t1_iu8jpqk wrote

Well, yes. I feel like this is obvious.

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