Antimatter

[Benm]

Would a single molecule of hydrogen fall in a vacuum? I would think it would have enough energy to still "whiz" around the place.

Its a valid question.. but would an ordinary hydrogen atom or molecule "fall" in a vacuum? I reckon it would not, but it would spend slightly more time near the bottom of the vessel that contains it, indicating gravity is doing its job.

A particle of anti-hydrogen would do exactly the same thing, but colliding with the walls of the vessel would destroy the particle instantly, so its not something you could easily demonstrate.

 

[thebucketmouse]

An antiparticle DOES have negative mass. That is why subatomic particle-antiparticle pairs can randomly appear and then annihilate each other.

The net energy of the interaction is 0

-Tony

Antiparticles have positive mass.

The net energy of the interaction is 0 because although both masses are annihilated, energy is released equal to the amount of mass annihilated.

 

[Xplorer877]

Antiparticles have positive mass.

The net energy of the interaction is 0 because although both masses are annihilated, energy is released equal to the amount of mass annihilated.

Before and after the fact that argument may be true, but during the instant that they exist, if they both had positive mass, that would break the laws of physics.

Stray energy does not just coalesce into a couple of particles and then back into energy. That's not what's happening. They appear out of nothing. Quantum theory says that at the quantum level there is always activity, even in a vacuum.

The ONLY way for two spontaneous particles (particle and anti-particle pair) to appear and not violate the law of conservation of energy is for one of them to have negative mass. Otherwise out of nothing, you have something, and if you have something, you have energy.

The thing that, I think, people get hung up on is thinking that a negative mass particles get repulsed by gravity. That isn't true.

The antimatter particle does have negative mass because that explains why black holes radiate off energy and eventually burn out. The negative-mass particles falling into the black hole slowly decrease the mass of the black hole. Again look up Hawking Radiation.

-Tony

 

[thebucketmouse]

Before and after the fact that argument may be true, but during the instant that they exist, if they both had positive mass, that would break the laws of physics.

No laws of physics are broken.. think about particle accelerators. Two particles are accelerated to ultra high speeds and given insane amounts of kinetic energy, and when they collide with each other going in opposite directions, the huge amount of energy converts into mass. Matter, and antimatter. Eventually the matter and antimatter will contact each other again and convert back into energy.

 

[Xplorer877]

No laws of physics are broken.. think about particle accelerators. Two particles are accelerated to ultra high speeds and given insane amounts of kinetic energy, and when they collide with each other going in opposite directions, the huge amount of energy converts into mass. Matter, and antimatter. Eventually the matter and antimatter will contact each other again and convert back into energy.

I get what you're say, yeah it starts as energy then turns into mass then back into energy, but that is not what I'm referring to.

Particle antiparticle pairs appear out of nothing, no energy or mass is present or changing forms. Unless one of the particles had negative mass it would violate Einsteins equation.

In order for them to appear spontaneously, out of noting and from nothing, the energy required to create them must be zero.
So,

E=mc^2

E = (m + -m)c^2 = 0

If the antimatter had positive mass ^that^ would not work.

-Tony

 

[Xplorer877]

Ok I hate to get you guys off of that subject, I read this thread and now my brain hurts.
I have a question does a black hole get bigger as it consumes a galaxie/matter or does it stay the same size?
After reading this thread I take it that a black hole will eventually disappear if it has no matter to consume?

I watch the Science channel and anything about black holes and CERN I watch, it really interests me.
I hope I don't sound too stupid!

You don't sound stupid, you're right actually.

Yes as black holes eat up matter they get bigger. The Schwarzschild Radius equation describes the the size you would have to compress something in order to make it into a black hole. Also that implies that for a given mass of the black hole it has a maximum size, otherwise it wouldn't form a black hole in the first place.

So yes as a black hole consumes matter it gets bigger. However, Hawking radiation says that if given enough time they will fizzle out and eventually get down to a certain size and become unstable and explode. But the rate at which black holes grow, for the average black hole lets say, is much larger than the rate at which it sizzles away.

-Tony

 

[thebucketmouse]

So why would multi billion dollar particle accelerators need to be built to create antiparticles, if they exist without any energy input or anything naturally?

 

[00Giorge]

You don't sound stupid, you're right actually.

Yes as black hole eat up matter they get bigger. The Schwarzschild Radius equation describes the the size you would have to compress something in order to make it into a black hole. Also that implies that for a given mass the black hole has a maximum size, otherwise it wouldn't form a black hole.

So yes as a black hole consumes matter it gets bigger. However, Hawking radiation say that if given enough time they will fizzle out and eventually get to a certain size and explode. But the rate at which black hole grows, for the average black hole lets say, is much larger than the rate at which it sizzles away.

-Tony

Of everything that I have seen on black holes they never have really have said that and I have always wanted to ask those questions. When I was in school they didn't know that much about black holes like they do now. Sometimes I wish I had time to go to school and learn more.

 

[Coherent Light]

Ok I hate to get you guys off of that subject, I read this thread and now my brain hurts.
I have a question does a black hole get bigger as it consumes a galaxie/matter or does it stay the same size?
After reading this thread I take it that a black hole will eventually disappear if it has no matter to consume?

I watch the Science channel and anything about black holes and CERN I watch, it really interests me.
I hope I don't sound too stupid!

A black hole does not increase in Physical size when additional matter falls on to it, but it's gravitational effect is increased by the amount of mass it gained. It is an infinitesimally small point that AFAIK no equation can express as a size We could wrap Our heads around. Infinitely small is just that, no other way I know how to describe it...It So Small It's not really there as We know it, but it's Gravity still effects the Space Time around it. The Matter locked in a Black Hole Is No longer a part of Our Universe in the traditional sense. Wow this is Deep.

 

[Xplorer877]

So why would multi billion dollar particle accelerators need to be built to create antiparticles, if they exist without any energy input or anything naturally?

LOL, well that's not the only reason we've built them. They let scientists conduct controlled collisions with particular particles. They have the biggest detectors in the world focused on an atomic scale area. The likelihood that a particle-antiparticle pair would appear right where they're looking is essentially zero.

That would be like pointing a telescope at random into space and waiting for a comet to zoom by to observe.

Of everything that I have seen on black holes they never have really have said that and I have always wanted to ask those questions. When I was in school they didn't know that much about black holes like they do now. Sometimes I wish I had time to go to school and learn more.

I feel the same way too, and that's what You Tube is for. :yh:

YouTube - Black Holes - Sixty Symbols

-Tony

 

[00Giorge]

A black hole does not increase in Physical size when additional matter falls on to it, but it's gravitational effect is increased by the amount of mass it gained. It is an infinitesimally small point that AFAIK no equation can express as a size We could wrap Our heads around. Infinitely small is just that, no other way I know how to describe it...It So Small It's not really there as We know it, but it's Gravity still effects the Space Time around it. The Matter locked in a Black Hole Is No longer a part of Our Universe in the traditional sense. Wow this is Deep.

I was watching the science channel and they were showing a galaxie that was being pulled into a black hole that is why I was asking if they got bigger.
I know that as everything is pulled in it is ripped to shreds. But they never said if the hole got bigger if it consumed a hole galaxie. I just figured they didn't know for sure.

 

[Coherent Light]

You could argue that it really does get bigger just not in a physical sense as the mass of the Galaxy it was consuming would be added to it's Gravitational effects. Physical size tho never changes. That Event Horizon aka point of no return would increase in diameter relative to the mass of the Black Hole. If You look at it that way it does get bigger. Gee I hope I am getting this right.

 

[Xplorer877]

You could argue that it really does get bigger just not in a physical sense as the mass of the Galaxy it was consuming would be added to it's Gravitational effects. Physical size tho never changes. That Event Horizon aka point of no return would increase in diameter relative to the mass of the Black Hole. If You look at it that way it does get bigger. Gee I hope I am getting this right.

Yes the Schwarzschild Radius equation can be used to determine the radius of the event horizon of black hole of a given mass.

The radius of the event horizon of the super massive black hole at the center of our galaxy is roughly 7 million miles.

-Tony

 

[00Giorge]

I understand what your saying, I haven't seen that video before. I have seen quite a few. Have you watched Trough the worm hole with Morgan Freeman? I record it and watch when I have time, and have picked up quite a bit from that.

I am having computer problems, internet explore keeps locking up.

 

[millirad]

Well the only thing that I'm sure of is that anti-matter neither falls up or down in a perfect vacuum. ;-)

 

[Coherent Light]

Yes to be On Topic Antimatter behaves no differently the normal matter in relation to gravity.