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chriscurtis
2007-Feb-28, 01:39 AM
Hi Gang,

The matter in this old gorgeously interesting Universe seems to be mostly comprised of the non antimatter variety.

If each particle of matter moving backwards in time is equivalent to its antimatter counterpart, then if you look at the spacetime of the Universe as a whole (rather than in one direction - the way we perceive the movement of time), then surely there isn't any missing antimatter, its all there existing in the other direction of time to which we perceive as humans.

What am I missing?

Cheers
Chris

GOURDHEAD
2007-Mar-01, 02:26 AM
What am I missing? Anti-time and anti-matter.

trinitree88
2007-Mar-01, 03:50 AM
Hi Gang,

The matter in this old gorgeously interesting Universe seems to be mostly comprised of the non antimatter variety.

If each particle of matter moving backwards in time is equivalent to its antimatter counterpart, then if you look at the spacetime of the Universe as a whole (rather than in one direction - the way we perceive the movement of time), then surely there isn't any missing antimatter, its all there existing in the other direction of time to which we perceive as humans.

What am I missing?

Cheers
Chris

Chris.
Whenever energy is converted to matter, a symmetrical quantity of anti-matter is produced. It's one of the ways a gamma ray can lose energy...by pair production, say electron/positron, or pi + meson/ pi - meson. But, in particle physics labs, it's always symmetrical. That conserves conservation laws. There is no experimental evidence that explains the presently observed excess of protons over anti-protons....or of electrons over positrons....or why there are exactly as many electrons as protons....in other words, us and our universe...none.
Cheers. Pete.

ngeo
2007-Mar-01, 04:15 AM
Chris.
Whenever energy is converted to matter, a symmetrical quantity of anti-matter is produced. It's one of the ways a gamma ray can lose energy...by pair production, say electron/positron, or pi + meson/ pi - meson. But, in particle physics labs, it's always symmetrical. That conserves conservation laws. There is no experimental evidence that explains the presently observed excess of protons over anti-protons....or of electrons over positrons....or why there are exactly as many electrons as protons....in other words, us and our universe...none.
Cheers. Pete.

Hi Pete,
How are the antimatter particles observed in the labs? Are they identified by their spins? (My idea would be that the universe is naturally one-handed.) Re the number of electrons and protons, wouldn't that suggest they come originally from neutrons?

BioSci
2007-Mar-01, 05:30 AM
Matter antimatter asymmetry is a very interesting problem for theories of cosmology. I think that the leading explanation involves a very small asymmetry in matter and antimatter reactions known as CP violation: http://en.wikipedia.org/wiki/CP-violation

snarkophilus
2007-Mar-01, 05:50 AM
Anti-matter (at least, the charged type) is typically observed by looking at tracks in cloud chambers. Basically, you have something like a steamy room, and when a particle passes through the steam, it leaves a trail behind where it pushed the steam out of the way. Now, you put an electric field in there. Positive particles curve one way, and negatives the other. How much they curve tells you what mass they are. So if you observe a particle that bends as much as an electron, but in the opposite direction, you can conclude that it is the electron's anti-particle (a positron).

You can also detect anti-matter by looking at annihilation tracks. You can predict theoretically what particles will be produced when a particle/anti-particle collide, so if you observe those all spreading from the same point, you can conclude that there was an annihilation there.

There are maybe other ways, but those are the classic ones, I think.

trinitree88
2007-Mar-03, 07:15 PM
Hi Pete,
How are the antimatter particles observed in the labs? Are they identified by their spins? (My idea would be that the universe is naturally one-handed.) Re the number of electrons and protons, wouldn't that suggest they come originally from neutrons?

Hi ngeo. Sorry about the slow response...death in the family this week, life has been better.
snarkophilus is mostly right, except that an electric field will accelerate charged particles, speeding up one charge and slowing the other...it's a magnetic field that curves the paths of both charges to the same degree. For a rookie demo, a small science supply cloud chamber...purchased for ~ $15.00, is placed in a fairly uniform magnetic field. That is achieved with a pair of Helmholtz coils...two coils of radius R, separated by the same R, one above the other. The interior volume of such a geometry has a very uniform field, and any cosmic ray muons, or electrons, or anti-muons, or positrons will curve according to right-hand rule.
It's how they discovered the positron..in cosmic ray emulsions, and cloud chambers...curving the "wrong" way. It was only a matter of time to see the anti-proton. The anti-neutron was trickier because, lacking charge, it doesn't curve....but it's decay products of anti-proton and positron (along with electron-type neutrino) were distinct.
P.S. The odd geometry of alleged UFO's seeming to match an enclosed pair of Helmholtz coils has been bantered about as "form follows function", but so far the jury is out on a meaningful relationship here. However it always pays to keep thinking, which I know you do. Cheers. Pete.

mugaliens
2007-Mar-04, 05:00 PM
How's this for a theory: The Big Bang occured as a result of a collision between two incredibly huge masses, one of matter, one of antimatter, both remnants from long dead universes (of bi-lobal universe). There wasn't parity, however, with matter outmassing the anti-matter by a very slight amount, say, the equivalent of all the matter and energy in our universe. Thus, the antimatter was nearly totally anhiliated or blown in the opposite direction, to form it's own, anti-matter (possibly smaller to much smaller antimatter universe), but the matter was simply heated to a kind of quantum plasma - not even quarks held together, and the energy released was enormous, mainly in the form of photons. All told, this photonic energy had a mass equivalent of 96% of the mass of our universe, precisely the missing amount called "dark matter."

Since it's not really matter, but energy, it's travelling as a wavefront at the speed of light at the very edge of our universe (forming it's leading edge). Since it's travelling away from us, we can't see it. However (and I'm guessing on this part, as I don't know the mechanics), photons occasionally collide or otherwise decay, and over time this decaying process, which sends still more photons (less than are involved in the decay) in random directions. Some comes back to us as the seemingly random, yet granular cosmic radiation background that was mapped out a while back.

Light may be massless, but we know that there's a momentum component to light.

What I'm wondering is if that momentum component, if backsolved, accounting for relativistic effects, would contain a mass equivalent. Thus, light may not have a mass, but the energy itself might neverless be able to generate a gravitational attraction.

I'm not certain if this effect could ever be measured in the lab, as the size of mass required to measure gravitational attraction given the accuracy of our instruments and to overcome the presence of so many other influences, would be fairly large (mountain-sized?), while the energy equivalent of that mass would probably blow half the planet away. Consider the fact that the Tsar Bomba (code-named Ivan) was a 50 MT, three-stage fission-fusion device who's detonation was so large that instruments measured it's seismic shock wave on it's third trip around the world, even though it was detonated just over 13,000 feet above the surface of the Earth. Even so, it weighed just 27 tons, a relative pipsqueak when it comes to producing gravity, and only a tiny fract of it's total mass was actually converted to energy.

The power released was 5.4×1024 watts or 5.4 yottawatts. That's a lot of watts! To put this into perspective, it's approximately 1% of the total output of the sun.

Before we think to highly of ourselves, the Chicxulub Crater even, an ancient impact crater buried underneath the Yucatán Peninsula, was caused by the impact of a 6-mile meteroite, and released the equivalent energy of 100 teratons. That's six orders of magnitude, or a billion times larger than Tsar Bomba.

Getting back to the matter/anti-matter issue...

What if the mainly matter portion of the universe was thus hurled a sizeable percentage of c in this direction, while the antimatter lobe was hurled a sizeable percentage in that direction? If symmetry must be preserved, this explanation would explain why we don't see much antimatter over here. However, I have some problems with this, as we'd be able to pinpoint an antimatter "hot spot," or a source of antimatter particles in the direction of the origen of the big bang, or given uniform spreading, at least from a spherical half of the universal sky and much less from the other half.

Alternatively, and not fully understanding what would happen if two matter and antimatter black holes were to collide, it could be that the two co-existed for the tiniest fraction of a second before anihilating one another, and that there the ratio between matter and antimatter was not symmetrical.

But the largest question that comes to my mind, and really seems to sink the entire theory, is that if pure energy actually had a gravitational component, wouldn't the Big Bang simply have gone "thud," as the gravitation component would have been strong enough to hold in everything, including light (energy)?

But perhaps there's no gravitational component to light. If so, and if there was a massive, universal black hole of matter and it collided with a massive, universal black hold of anti-matter, then when that matter was converted to energy, providing there was at least some assymetry, then the subsequent energy could have produced a massive ball of incredible energy no longer bound by the gravitation pull produced by the matter, and BANG!

The universe begun.

Is there an astrophysicist in the house that could lend some hard science to my meandering thoughts in a way which is contructive and not confusing?

If so, please do!

By the way, I'm starting a new thread containing just the last portion of this thought.

mugaliens
2007-Mar-09, 02:10 PM
Well?

trinitree88
2007-Mar-10, 07:08 AM
Well?

insomnia. OK. Actually, there's an interesting idea there Mugs. Matter and antimatter are distinguishable of this side of the event horizon by their properties. I'm wondering if there's a distinguishablity of the two black holes formed...one from matter only, the other from antimatter. It seems that once again, that Lorentz Invariance disappears at the event horizon, and these two collections now have the same properties viewed from this side. Pete.

Michael Noonan
2007-Mar-10, 08:47 AM
All right

How about you are right about the end of the cycle being binary but it is charge and anti charge.

The connection through quantum where nothing touches prevents opposite charged particles from interacting. But the presence of each induces a charge around the matter giving an opposite charged field ie protons opposite is the electron, the anti protons opposite is the positron.

The only way to connect them is in spacial dimension so the collapse looks like a horseshoe magnet touching at the ends with the loop shrinking

At the contact in spatial dimension and only in collapse is there a balance of charge and total release of gravity.

This causes not anti matter but string with virtually no gravity and that by inference gravity must increase with the size of the particle. Conservation of time equal zero and conversion of gravity to an opposing energy which causes each universe to be opposite but equal to the other.

Result no anti matter, no anihilation no problem all conserved in an oscillating universe.

Cheers

Michael Noonan
2007-Mar-10, 09:00 AM
The simple test of this is can you easily pull a closed tube of water apart in a vacuum.

This is easy enough to test in a lab. If not then what is holding the water together?

Cheers