Questions from the other side

[Baby Astronaut]

1. Does anti-matter have gravity?

 

2. If the universe expanded faster than light at its very beginning, then what caused all the stuff within it to slow down enough for any light to reach us from other sources?

[ydoaPs]

1. Does anti-matter have gravity?

Yes. Antiparticles have the same mass as their counterparts.

 

2. If the universe expanded faster than light at its very beginning, then what caused all the stuff within it to slow down enough for any light to reach us from other sources?

 

Presumably gravity and electromagnatism.

[Baby Astronaut]

Yes. Antiparticles have the same mass as their counterparts.

Would anti-bosons exist too? (anti-force carriers?)

 

 

Presumably gravity and electromagnatism.

For gravity, I can't see how the gravity waves ever caught up to objects that were receding faster-than-light due to expansion.

 

Also, please clarify how electromagnetism would've slowed distant objects.

[ajb]

Would anti-bosons exist too? (anti-force carriers?)

 

Yes, boson have antiparticles also.

 

 

For gravity, I can't see how the gravity waves ever caught up to objects that were receding faster-than-light due to expansion.

Also, please clarify how electromagnetism would've slowed distant objects.

 

A modified version of inflation (I think is now generally accepted) by Linde called "slow roll inflation" solves this problem and gives sensible reheating.

 

In this model inflation is coursed by a scalar field rolling down a potential. If the field rolls slowly compared to the expansion of the universe inflation occurs. If the potential becomes steeper the inflation stops and reheating occurs.

 

The original model by Guth has some difficulties with inflation ending and reheating.

[Baby Astronaut]

Yes, boson have antiparticles also.

So if gravitons were to exist their antiparticles would perhaps be anti-gravity? Or the anti-Higgs boson would be the producer of anti-matter?

 

 

A modified version of inflation (I think is now generally accepted) by Linde called "slow roll inflation" solves this problem and gives sensible reheating.

Nice, thanks. I shall check it out.

Edited June 19, 2010 by Baby Astronaut
whoops

[ajb]

So if gravitons were to exist their antiparticles would perhaps be anti-gravity?

 

No, an anti-graviton would be identified with a graviton, just as the anti-photon and photon are identified.

[Baby Astronaut]

I meant: would anti-gravity produce effects of anti gravity? I'm not quite sure if that's what your answer referenced. As for the original existence of anti-matter, do you know if that was possibly created by the anit-Higgs boson?

[elas]

'The Particle Explosion' by Close et al does not give anti-particles for gauge bosons with '0' charge, but only for gauge bosons with charge +1 or -1.

 

'O' charge particles are said to be their own anti-particle, that is to say that one particle fulfils both functions; this would apply to the '0' charge graviton and therefore also to gravity.

Edited June 19, 2010 by elas

[Baby Astronaut]

'O' charge particles are said to be their own anti-particle, that is to say that one particle fulfils both functions; this would apply to the '0' charge graviton and therefore also to gravity.

Whoops, I did mean to say anti-gravitons producing effects of anti gravity.

 

Something odd, how couldn't being their own anti-particle end up destroying the boson?

[timo]

Also note that the Higgs boson is associated with a mechanism that creates mass (-terms), not a mechanism that creates matter.

[elas]

Whoops, I did mean to say anti-gravitons producing effects of anti gravity.

 

Something odd, how couldn't being their own anti-particle end up destroying the boson?

 

In current teaching there is no answer to your question. Speculation from people like me results in the forum being transferred to 'speculations' much to the (justified) annoyance of others. I will avoid speculation by suggesting that you ask yourself what do physicist mean when they use the minus term? or what brings the minus term into play?

 

Accountants, stock keepers, doctors, builders etc all take the minus sign to mean something that is missing; only particle and quantum physicists take the minus sign as indicating something that exists. The solution is to find the missing entity; and of course, when found it has a positive existance.

 

There is, an exception; which occurs when the minus sign is used to indicate a change of direction. Unfortunately a change in direction (usually the direction of force) is sometimes used to imply the existance a negative entity when in reality it is a positive entity moving in the opposite direction; but to find the positive entity it is often necessary to answer both questions.

 

the answer given by timo is not strictly correct. There is no clear definition of mass it may or may not include matter. See:

http://en.wikipedia.org/wiki/Matter

Edited June 21, 2010 by elas