Antimatter

[gulthaw]

I'm not an expertise about science matters but i've read a lot and searched more and more trying to imagine how can a piece of antimatter be.

First, i though it should be like black, obsidian black, stone. Atracting everything, making impossible to reach it and with a force field surounding it so we can see it.

But i'm no longer sure about that description.

I searched about this and other science related things and I can imagine everything but the antimatter.

Which form should have? Should it be round? (everyone knows liquid materia take that form without gravity, solid materia may took that form too... take a lok to our known planets)
Should it have another kind of form? Should it be so bright even if is black that we can't take a direct look?

Those things are in my mind and I cannot clarify nor view some truth over them, any ideas? ^^

P.S. Sorry for any typo, english is not my mother language and I'm doing my best

 

[Gibsons]

Originally posted by: gulthaw
I'm not an expertise about science matters but i've read a lot and searched more and more trying to imagine how can a piece of antimatter be.

First, i though it should be like black, obsidian black, stone. Atracting everything, making impossible to reach it and with a force field surounding it so we can see it.

But i'm no longer sure about that description.

I searched about this and other science related things and I can imagine everything but the antimatter.

Which form should have? Should it be round? (everyone knows liquid materia take that form without gravity, solid materia may took that form too... take a lok to our known planets)
Should it have another kind of form? Should it be so bright even if is black that we can't take a direct look?

Those things are in my mind and I cannot clarify nor view some truth over them, any ideas? ^^

P.S. Sorry for any typo, english is not my mother language and I'm doing my best

Antimatter will behave and look much like normal matter. If you made anti-hydrogen and anti-oxygen, you could then make anti-water. Antiwater would have the same molecular weight, same freezing and boiling points as 'regular' water.

The difference is if the antiwater comes in contact with 'regular' matter, you get a big explosion.

 

[gulthaw]

Originally posted by: Gibsons

Antimatter will behave and look much like normal matter. If you made anti-hydrogen and anti-oxygen, you could then make anti-water. Antiwater would have the same molecular weight, same freezing and boiling points as 'regular' water.

The difference is if the antiwater comes in contact with 'regular' matter, you get a big explosion.

But, since antimatter should have low-energy positrons to neutralize the ions that should be different in some way other than molecular.

The aspect will be very different I think. And if we talk about particles of water and 'antiwater' this is kinda weird... water is HOH and the relationship between the particles creates the HOH, so... this relationship will be different for 'antiwater' since the ions and electrons are no longer this but positrons.

This is merely a supposition

P.S. Again, sorry for any typo ^^

 

[Gibsons]

Originally posted by: gulthaw

Originally posted by: Gibsons

Antimatter will behave and look much like normal matter. If you made anti-hydrogen and anti-oxygen, you could then make anti-water. Antiwater would have the same molecular weight, same freezing and boiling points as 'regular' water.

The difference is if the antiwater comes in contact with 'regular' matter, you get a big explosion.

But, since antimatter should have low-energy positrons to neutralize the ions that should be different in some way other than molecular.

No... the charge on the positron will be the same magnitude as an electron, just positive rather than negative. Their mass will also be the same. The antiprotons in the anti-water will have the same magnitude of charge and the same mass as protons.

I don't know what you're getting at when you say "neutralize the ions."

The aspect will be very different I think. And if we talk about particles of water and 'antiwater' this is kinda weird... water is HOH and the relationship between the particles creates the HOH, so... this relationship will be different for 'antiwater' since the ions and electrons are no longer this but positrons.

The orbitals occupied by the positrons in anti-water will be of the same shape/density/or whatever that the electrons in water occupy. The bonds connecting the H to the O will have the same length and strength.

 

[pcy]

Hi,


Yes... but are we sure about the explosion bit.


If E = mc*2

Then antimatter would have -ve energy and bringing together a piece of matter and of anti-matter would have no net energy outcome as the result of the destruction of both.



Peter

 

[f95toli]

Originally posted by: pcy
Hi,


Yes... but are we sure about the explosion bit.


If E = mc*2

Then antimatter would have -ve energy and bringing together a piece of matter and of anti-matter would have no net energy outcome as the result of the destruction of both.



Peter

Why? E=mc^2 is positive also for anti-matter. Anti-matter has a negative CHARGE but the mass is the same as for ordinary matter.

 

[pcy]

Hi,

If that were so, surely they would not annileate eachother?

Peter

 

[blackllotus]

Originally posted by: gulthaw
The aspect will be very different I think. And if we talk about particles of water and 'antiwater' this is kinda weird... water is HOH and the relationship between the particles creates the HOH, so... this relationship will be different for 'antiwater' since the ions and electrons are no longer this but positrons.

Antimatter acts exactly like matter. There is nothing wrong with antimatter water, antimatter air, or even an antimatter computer... that is, as long as you can keep them from coming into contact with matter.

 

[Qriz]

Antimatter doesn't exist on Earth except very briefly and in very small quantities during processes like radioactive decay.

 

[blackllotus]

Originally posted by: Qriz
Antimatter doesn't exist on Earth except very briefly and in very small quantities during processes like radioactive decay.

We're not even sure of what kind of quantities of antimatter exist within the universe. For all we know the rest of the universe could contain both matter or antimatter galaxies, or it could be just like earth; where the vast majority of everything is made up of matter.

 

[DrPizza]

Originally posted by: blackllotus

Originally posted by: Qriz
Antimatter doesn't exist on Earth except very briefly and in very small quantities during processes like radioactive decay.

We're not even sure of what kind of quantities of antimatter exist within the universe. For all we know the rest of the universe could contain both matter or antimatter galaxies, or it could be just like earth; where the vast majority of everything is made up of matter.

It's currently thought that the percent of the universe that is anti-matter is less than 1 trillionth of a percent (or some incredibly small amount like that.)

IF there was a region of antimatter then there would need to be some "border" between anti-matter and matter. Since "stuff" in space tends to move about a bit, we would see tell-tale signs of the gamma radiation from matter-anti-matter annihilations.

Also, a few years ago, a satellite was sent up. It was supposed to detect any antimatter particles that struck some sort of large detector. None found. A new satellite has been launched (or is going to be launched in the near future) with much greater sensitivity.


Also, maybe this will help you understand the difference between matter and anti-matter:
If our solar system/galaxy/etc was made entirely out of what we now call anti-matter, everything would be exactly the same as it is now, except we'd still call it matter. It makes no difference.

 

[confused1234]

Originally posted by: Qriz
Antimatter doesn't exist on Earth except very briefly and in very small quantities during processes like radioactive decay.

particle accelerator labs create it.

 

[silverpig]

There are plenty of anti-neutrinos floating about... billions pass through your body all the time.

 

[Qriz]

Originally posted by: confused1234

Originally posted by: Qriz
Antimatter doesn't exist on Earth except very briefly and in very small quantities during processes like radioactive decay.

particle accelerator labs create it.

I meant naturally. "According to an article on the website of the CERN laboratories, which produces antimatter on a regular basis, "If we could assemble all the antimatter we've ever made at CERN and annihilate it with matter, we would have enough energy to light a single electric light bulb for a few minutes."" The cost to develop enough antimatter to really do anything for us would be enourmous. If we could make antimatter in the amounts we'd like, time travel wouldn't be so far-fetched an idea.

 

[DrPizza]

Originally posted by: Qriz

Originally posted by: confused1234

Originally posted by: Qriz
Antimatter doesn't exist on Earth except very briefly and in very small quantities during processes like radioactive decay.

particle accelerator labs create it.

I meant naturally. "According to an article on the website of the CERN laboratories, which produces antimatter on a regular basis, "If we could assemble all the antimatter we've ever made at CERN and annihilate it with matter, we would have enough energy to light a single electric light bulb for a few minutes."" The cost to develop enough antimatter to really do anything for us would be enourmous. If we could make antimatter in the amounts we'd like, time travel wouldn't be so far-fetched an idea.

IIRC, antimatter is made all the time at the sun in solar flares, and when particles from the sun strike the upper atmosphere. (in addition to radioactive decay for natural sources.)

 

[silverpig]

Originally posted by: DrPizza
IIRC, antimatter is made all the time at the sun in solar flares, and when particles from the sun strike the upper atmosphere. (in addition to radioactive decay for natural sources.)

Antimatter is made in the core of the sun continuously... Part of the reaction is that a neutron gets turned into a proton + an electron + an electron antineutrino.

When solar flares erupt, they send tons of highly energetic particles (protons mainly by mass) towards the earth. These protons slam into our atmosphere and turn into all sorts of exotic particles such as muons, positrons, etc... there's definitely some antimatter in there.

 

[Jahee]

one of the things i've always wondered is why there would be an explosion when anti-matter meets matter... anyone care to explain? i'm only a chemistry student (at high school?? i'm 18) so i dont have a full understanding of all these things yet.

 

[Rockinacoustic]

Originally posted by: Jahee
one of the things i've always wondered is why there would be an explosion when anti-matter meets matter... anyone care to explain? i'm only a chemistry student (at high school?? i'm 18) so i dont have a full understanding of all these things yet.

Yeah, what exactly is the reaction involved that causes these two to 'explode' upon contact?

 

[Mark R]

Originally posted by: Rockinacoustic
Yeah, what exactly is the reaction involved that causes these two to 'explode' upon contact?

In the case of the electron/anti-electron reaction:

e- + e+ -> 2 ?

Essentially, the electron and positron vanish and they are replaced by 2 photons.

The mass of the particles is destroyed and converted into pure energy, so each of the photons has the energy derived from the mass of one of the particles (E=mc²). If you work this out, each photon gets 511 keV of energy - making it a moderate energy gamma ray.

In order to conserve momentum, the 2 gamma rays are emitted in opposite directions. This interesting property is made use of in PET scanning.

Reactions between neutrons/anti-neutrons, protons/anti-protons, etc. happen in exactly the same way - but because there is so much energy (and because protons, etc. are made of individual quarks), you can get loads of different types of photon produced and cascades of smaller particles (like electrons and positrons). It's random as to the exact reaction that occurs, although some reactions are more likely than others. However, all reactions have a common feature in that the total energy/mass, total momentum and total charge are preserved.

 

[ForumMaster]

anti-matter, except for it's opposite electrical charge, should act and look the same as regular matter, in theory. scientists think that there may be whole parts of the galaxy that are antimatter. there could an exact duplicate of this galaxy just made of anti-matter.

 

[DrPizza]

I think the idea of anti-matter galaxies has been, for the most part, thrown out.
One of the biggest issues has been why the universe favors matter over anti-matter. If there were anti-matter galaxies, then this wouldn't be an issue; it would simply be explained by "we just happen to live in a matter part of the universe." And "any part has to be either predominately matter or predominately anti-matter, otherwise it would annihilate itself."