anti matter?

[warped space]

ok so i have been doing a little bit of research about it and it is maid of positrons or opposite charged electrons and opposite charged protons but when it comes in contact with (our perspective) normal matter it annihilates why is this really and if it is a anti particle does it have any sort of anti gravity or is there even a way to have anti gravity exist

[swansont]

As far as we know, i.e. to the extent it has been tested, it does not have antigravity. There are people trapping antihydrogen who are aiming to improve testing of this.

[warped space]

Do you have a link where I could stay up to date with there research

[Aethelwulf]

As far as we know, i.e. to the extent it has been tested, it does not have antigravity. There are people trapping antihydrogen who are aiming to improve testing of this.

 

We haven't actually tested it enough to be certain. From the last records I read... The amount we have made is miniscule.

 

Do you have a link where I could stay up to date with there research

 

The page I read this from was a NASA page, if my memory serves (which it usually does).

 

Trust me, we have not created enough of the stuff to see noticable gravitational effects.

[warped space]

Ok thank you for the help

[Aethelwulf]

you're welcome.

[ACG52]

Trust me, we have not created enough of the stuff to see noticable gravitational effects.

 

No, but we have weighed it with great accuracy at CERN. If there were antigravitational effects, it would show in the weight.

 

http://press.web.cer...1/PR10.11E.html

Edited June 18, 2012 by ACG52

[warped space]

So could this be the difference between matter and anti matter

 

And another question however theoretical it is if you have an anti gravity and a gravity particle (so to speak) would it create any form of one directional momentum or energy

[imatfaal]

No, but we have weighed it with great accuracy at CERN. If there were antigravitational effects, it would show in the weight.

 

http://press.web.cer...1/PR10.11E.html

 

I haven't read up on the technique - but wuold this not be measuring inertial mass (and please let's not get into a debate on mass); there would still be the possibility (very slight) that for antimatter gravitational mass does not equal inertial mass. I realise that for everything else it does equal - but antimatter is not simple matter

[Enthalpy]

If antimatter had negative gravitational mass, wouldn't black holes create huge amounts of matter and antimatter, with the latter being expelled towards the exterior of the horizon, that is to the univers we can observe?

 

Hawking radiation is faint because the short-distance tunneling effect following pair creation must take advantage of the tiny gravitation curvature at the black hole so the falling particle loses more potential energy than the expelled one gains - explaining why small holes with a stronger curvature are more efficient. But if antimatter loses potential energy by flying away, then the tunneling effect could take advantage of the gravitation field, not just its tiny curvature, and pair production would be hugely efficient.

 

My guess is that the absence of such an expulsion of antimatter towards our observable universe proves that antimatter has a normal gravitation mass, and even must put bounds over any possible mass difference between normal and antimatter. That would make a funny little physics project for a student.

 

Marc Schaefer, aka Enthalpy

[imatfaal]

Mark - I have never really understood Hawking radiation (I got to the bit where Hawking said - the preceding description is heuristic and should not be taken seriously - and gave up) What you are saying makes sense - and I wish I could tell if it was right or not.

[warped space]

If antimatter had negative gravitational mass, wouldn't black holes create huge amounts of matter and antimatter, with the latter being expelled towards the exterior of the horizon, that is to the univers we can observe?

 

Hawking radiation is faint because the short-distance tunneling effect following pair creation must take advantage of the tiny gravitation curvature at the black hole so the falling particle loses more potential energy than the expelled one gains - explaining why small holes with a stronger curvature are more efficient. But if antimatter loses potential energy by flying away, then the tunneling effect could take advantage of the gravitation field, not just its tiny curvature, and pair production would be hugely efficient.

 

My guess is that the absence of such an expulsion of antimatter towards our observable universe proves that antimatter has a normal gravitation mass, and even must put bounds over any possible mass difference between normal and antimatter. That would make a funny little physics project for a student.

 

Marc Schaefer, aka Enthalpy

 

i don't know a lot about hawking radiation but i did a little research and at the bottom of the article that i read (http://casa.colorado.edu/~ajsh/hawk.html) it said that at the last seconds of a black hole it would create something that the article called a hadronic fire ball which would emit large amounts of gama-rays and a large assortment of other particles as that disintegrated well i no that we have never really witnessed such an event but do the laws of physics eliminate the possibility that it could also emit large amounts of matter and anti matter and is it possible to just barely push something to black hole gravity and make it small enough to where it would evaporate within seconds not killing everything on earth and but making one of these "hadronic fireballs" and harnessing its energy

 

by particles i was referring to wavelengths of light not massive particles

[juanrga]

ok so i have been doing a little bit of research about it and it is maid of positrons or opposite charged electrons and opposite charged protons but when it comes in contact with (our perspective) normal matter it annihilates why is this really and if it is a anti particle does it have any sort of anti gravity or is there even a way to have anti gravity exist

 

The standard gravity model says that antimatter falls in exactly the same manner as normal matter. Although some speculative models claim otherwise.

[D H]

No, but we have weighed it with great accuracy at CERN. If there were antigravitational effects, it would show in the weight.

 

http://press.web.cer...1/PR10.11E.html

That's not weighing, it's measuring inertial mass. (Aside: What's the verb for "taking the mass of"?). There are experiments either underway or in the planning stage to weigh antimatter. Why? For one thing, as Juan mentioned, there are speculative models that posit modifications to the equivalence principle for antimatter. For another, physicists test their assertions. The equivalence principle asserts that inertial mass, passive gravitational mass, and active gravitational mass are identical. That's a pretty strong assertion! Physics ≠ philosophy. Physicists test their assertions.

[Enthalpy]

Physicists test their assertions.

 

Provided they're aware of the assertions they make... In the 19th century, no physicist wrote at the beginning of his calculation "we assume time is identical for everyone".

 

This is something I found ridiculous from some physics teachers. "Write down all assumptions you make", they used to say! But well, these were teachers - true physicists didn't tell us such a thing.