“In a paper published today in Nature, the ALPHA collaboration at CERN’s Antimatter Factory shows that, within the precision of their experiment, atoms of antihydrogen – a positron orbiting an antiproton – fall to Earth in the same way as their matter equivalents.”

https://home.cern/news/news/physics/alpha-experiment-cern-observes-influence-gravity-antimatter

"Antimatter falls like matter"

Says clumsy scientist who dropped it.

15 minutes ago, John Cuthber said:

Says clumsy scientist who dropped it.

Antiscientist.

 

This gets boring.Einstein (et al) was right.

So was it just 50/50 which form of matter won out  at the beginning?

Or is matter more than just the mirror image of anti matter?

9 minutes ago, geordief said:

This gets boring.Einstein (et al) was right.

So was it just 50/50 which form of matter won out  at the beginning?

Or is matter more than just the mirror image of anti matter?

That’s an issue of baryon asymmetry, which is unresolved. Neither one should have won out, but one did, or there was more of one than the other from the start. 

23 minutes ago, swansont said:

That’s an issue of baryon asymmetry, which is unresolved. Neither one should have won out, but one did, or there was more of one than the other from the start. 

Is there a reason for the proportion of one form to the other that has been observed?

Is that promotion expected to be the same everywhere in the observable universe?

 

Edit:a quick Google search brings up this Wikipedia page which seems to go  into the question

 

https://en.m.wikipedia.org/wiki/Baryon_asymmetry

Edited September 27, 20232 yr by geordief

17 hours ago, swansont said:

“In a paper published today in Nature, the ALPHA collaboration at CERN’s Antimatter Factory shows that, within the precision of their experiment, atoms of antihydrogen – a positron orbiting an antiproton – fall to Earth in the same way as their matter equivalents.”

https://home.cern/news/news/physics/alpha-experiment-cern-observes-influence-gravity-antimatter

Well, that makes gravity easier/harder to understand.

22 hours ago, swansont said:

That’s an issue of baryon asymmetry, which is unresolved. Neither one should have won out, but one did, or there was more of one than the other from the start. 

Yes I have seen this idea before,  so there was more normal matter from the start.  I think if matter annihilates antimatter you get energy,  not fully sure.  

 

1 hour ago, paulsutton said:

Yes I have seen this idea before,  so there was more normal matter from the start.  I think if matter annihilates antimatter you get energy,  not fully sure.  

 

You get photons, or you get matter/antimatter pairs. We’ve seen reactions that yield more matter than antimatter in some lepton reactions (CP violation), but it doesn’t explain the baryon asymmetry.

I didn't think it was a question that hadn't already been answered. Doubtless I have missed something observed/published that suggested antimatter could be like flubber.

15 minutes ago, Ken Fabian said:

I didn't think it was a question that hadn't already been answered. Doubtless I have missed something observed/published that suggested antimatter could be like flubber.

It hadn’t been answered experimentally. Theory has to be confirmed. Science has had some surprises that required adjustments in the models.

1 hour ago, Ken Fabian said:

I didn't think it was a question that hadn't already been answered. Doubtless I have missed something observed/published that suggested antimatter could be like flubber.

Flubber ?  +1

 

That was a good film, (the 1961 original),  complete with a mad professor.

Edited September 28, 20232 yr by studiot

Kinda sad really, antigravity antimatter would have been much more useful and interesting. 

Matter and antimatter made up of the same stuff...the stuff is influenced similarly by gravity probably,therefore,matter and anti matter interact  in the same manner with gravity..after all, matter-anti matter annihilate to produce energy which is equivalent to  mass c^2.

22 hours ago, swansont said:

You get photons, or you get matter/antimatter pairs. We’ve seen reactions that yield more matter than antimatter in some lepton reactions (CP violation), but it doesn’t explain the baryon asymmetry.

In case anyone's interested...

In addition to baryon number non-conservation, one would need T (=CP) violation, plus C violation alone, plus a universe out of equilibrium --if I remember correctly-- for baryon asymmetry. 

As we already know of C and CP violation, T would be automatically satisfied if CPT holds, which we believe to be the case.

https://en.wikipedia.org/wiki/Baryogenesis#GUT_Baryogenesis_under_Sakharov_conditions

6 hours ago, joigus said:

plus a universe out of equilibrium --

Maybe given enough time it's equilibrium... forward arrow of time (Universe expansion) favors matter formation while backward arrow of time( Universe contraction) favors antimatter formation... Probably leading to an aspect of global time and local time hence T asymmetry,which leads to T violation which is difficult to detect experimentary since we are local observers...the mere fact that matter dorminates presently maybe of itself enough to prove T violation.

it seems that if the universe formed both types, then due to random fluctuations within the forming process, more of one should have been created than the other. The bulk that annialation could have been what powered the big bang. It was arbitrary which one persisted to be called "matter".

1 hour ago, hoola said:

it seems that if the universe formed both types, then due to random fluctuations within the forming process, more of one should have been created than the other. The bulk that annialation could have been what powered the big bang. It was arbitrary which one persisted to be called "matter".

The unbalance cannot come from random fluctuations. Electric charge is exactly conserved --as every other gauge charge. You really need a mechanism to nudge things out of balance.

Look up Sakharov conditions for baryogenesis.

Oh, look. I thought I'd said it, and indeed I did...

On 9/29/2023 at 8:59 PM, joigus said:

As we already know of C and CP violation, T would be automatically satisfied if CPT holds, which we believe to be the case.

https://en.wikipedia.org/wiki/Baryogenesis#GUT_Baryogenesis_under_Sakharov_conditions

This is no random fluctuation.

Either that or everything started out unbalanced for some mysterious reason --which is always possible.

If the universe came about by mathematical calculations, perhaps a mistake was made in these calculations since math is somewhat unstable (Godel), leading to this issue.

Edited October 28, 20232 yr by hoola

Is there anyone who suggests the universe “came about by mathematical calculations”?

Godel said math is unstable?

Tegmark, Wheeler, Pythagoras. In a certain sense, did he not say that with the incompletnes?

 

Edited October 29, 20232 yr by hoola

10 hours ago, hoola said:

Tegmark, Wheeler, Pythagoras. In a certain sense, did he not say that with the incompletnes?

 

Incompleteness is not instability.

On 9/27/2023 at 3:08 PM, geordief said:

Or is matter more than just the mirror image of anti matter?

Matter as distinct from antimatter comes from the condensation and collapse of the latter, like antineutrinos, positrons, antiquarks, into dark matter about the Planck scale so that their dipole moments are too small to interact with each other and with regular matter whose dipole moments are greater than the neutrino’s. The arrow and rate of time for bodies is essentially fundamentally determined by their dipole moments.

17 minutes ago, Alysdexic said:

Matter as distinct from antimatter comes from the condensation and collapse of the latter, like antineutrinos, positrons, antiquarks, into dark matter about the Planck scale so that their dipole moments are too small to interact with each other and with regular matter whose dipole moments are greater than the neutrino’s. The arrow and rate of time for bodies is essentially fundamentally determined by their dipole moments.

Citation needed.