<p>I presume you're asking about the <a href="https://www.google.co.uk/search?q=mystery+antimatter&amp;*&amp;cad=h" rel="nofollow noreferrer">mystery of the missing antimatter</a>. This features extensively in the popular and scientific media. For example the CERN webpage on <a href="https://home.cern/science/physics/matter-antimatter-asymmetry-problem" rel="nofollow noreferrer">the matter-antimatter asymmetry problem</a> is fairly typical. It says the Big Bang should have created equal amounts of matter and antimatter, but everything we see today is made almost entirely of matter. It goes on to say <em>“something must have happened to tip the balance. One of the greatest challenges in physics is to figure out what happened to the antimatter”</em>. </p>

<p>I think it's something of a "clickbait" mystery I'm afraid, to try to curry favour with the paying public. Why do I think that? Because there’s baryon asymmetry, where we see lots of protons but hardly any antiprotons, and there’s also lepton asymmetry where we see lots of electrons but hardly any positrons. And they <em>match</em>. Take a look at positronium. It’s <em>“a system consisting of an electron and its anti-particle, a positron, bound together into an exotic atom”.</em> The electron is matter, and the positron is antimatter. Positronium however is neither matter nor antimatter. It’s <em>both</em>. It’s an exotic atom. Now see <a href="https://books.google.co.uk/books?id=Q74GCAAAQBAJ&amp;pg=PA314&amp;lpg=PA314&amp;dq=%22light+hydrogen%22&amp;#v=onepage&amp;q=%22light%20hydrogen%22&amp;f=false" rel="nofollow noreferrer">page 314</a> of <em>photon and electron collisions with atoms and molecules</em> edited by Philip Burke and Charles Joachain. It says <em>“the positronium atom thus created is in essence a very light hydrogen atom”</em>. So positronium is both matter and antimatter, and it’s like light hydrogen. </p>

<p>The clear inference from that is <em>hydrogen is also a combination of matter and antimatter</em>. We say the electron is matter, and the proton too. But why? Surely since the proton is more like the positron than the electron, we ought to say the proton is the antimatter. Like this:</p>

<p><a href="https://i.sstatic.net/RdUNN.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/RdUNN.jpg" alt="enter image description here"></a></p>

<p>That would mean antimatter is a lot more common than people say. The proton mass is 1836 times the electron mass. Which would mean that weight for weight, 99.95% of everything around you is made of antimatter. Where’s all the antimatter gone? Nowhere. Because it’s hiding in plain sight. Because truth be told and by and large, <em>you are made of it</em>.</p>

CC BY-SA 4.0
2018-12-03T14:34:57.040Z
Since the answer has been accepted, I'll add my explanation for the downvote: This answer is mostly incorrect. Claiming that the electron should be called antimatter doesn't fix baryon *or* lepton asymmetry. This is a personal theory, not science.
HDE 226868
CC BY-SA 4.0
2018-12-03T14:51:59.880Z
Right. This is a somehow inspiring answer that doesn't answer the question about what/how an asymmetry is seen. And @HDE 226868★
Alchimista
CC BY-SA 4.0
2018-12-03T17:39:47.057Z
@HDE 226868 : please note that _baryon asymmetry is matched by lepton asymmetry_ is not some personal theory. It's science. As is positronium _“is in essence a very light hydrogen atom”_. Along with the particle properties - the proton is indeed more like the positron than it's like the electron. What _isn't_ science is dismissing the above and peddling mystery instead.
John Duffield
CC BY-SA 4.0
2018-12-03T17:58:35.343Z
@JohnDuffield I have no idea what you mean by that quote. A proton and an electron are not the same thing as a positron and an electron. They're completely different - different masses, constituent particles, baryon/lepton number, etc.
HDE 226868
CC BY-SA 4.0
2018-12-03T19:10:49.293Z
@HDE 226868 : positronium is described as "light hydrogen" by various authors. You can [Google it](https://www.google.com/search?biw=1366&bih=626&tbs=li%3A1&ei=O38FXMjrIYbbgAazjb3IAQ&q=positronium+%22light+hydrogen%22+-%22hydrogen-like%22+-duffield&oq=positronium+%22light+hydrogen%22+-%22hydrogen-like%22+-duffield&gs_l=psy-ab.3...20869.22918..23607...0.0..0.54.463.10......0....1..gws-wiz.82p1Q5qk1RE).
John Duffield
CC BY-SA 4.0
2018-12-03T19:36:50.433Z
@JohnDuffield Positronium has been nicknamed "Light Hydrogen" due to it vaguely sharing some similar traits. However, the reality is that any particle-antiparticle pair (an Onium) is not just a light version of a traditional atom. Your answer is simply not correct.
Arkenstein XII
CC BY-SA 4.0
2018-12-03T22:07:52.940Z
@Arkenstein XII : there's nothing vague about positronium chemistry, or about the particle properties which tell you that the proton is more like the  positron than the electron, or about the baryon asymmetry being matched by lepton asymmetry. My answer might be unfamiliar to you, but you can't actually point to any actual flaw in it. Saying _your answer is simply not correct_ is no substitute for facts and evidence like I provide. Perhaps you'll only believe what I'm saying once you've seen it in a paper in Nature?
John Duffield
CC BY-SA 4.0
2018-12-03T22:31:41.877Z
@JohnDuffield I was not suggesting that there is anything vague about the physics. In fact, the physics is quite clear. A Positron, like an Electron, is a lepton. It has the same mass as an electron, but has the opposite (+) charge, a trait it shares with a Proton. Protons, on the other hand, are baryons, and are composed of quarks and are orders of magnitude more massive. The only property that is shared between a Positron and a Proton is the charge. This is not enough to claim that they are more alike than a Positron and an Electron are, when the later clearly share vastly more traits.
Arkenstein XII
CC BY-SA 4.0
2018-12-02T17:01:36.080Z
2018-12-02T17:01:36.080Z
John Duffield
<p>Question implies all, why is that? Why we exist even after equally creation of matter and anti-matter, any possible exception?</p>

CC BY-SA 4.0
2018-12-01T17:33:40.730Z
Nobody knows. Perhaps you could rephrase your question? To something like - are there any proposed ideas or mechanisms that might lead to... ?
ProfRob
CC BY-SA 4.0
2018-12-01T17:37:25.090Z
Yeah, I meant to that.
Rahul Singh
CC BY-SA 4.0
2018-12-01T23:02:09.670Z
Why do you think there was equal creation of matter and anti-matter? The accepted theories do not require this.
Rory Alsop
CC BY-SA 4.0
2018-12-02T00:21:00.503Z
[Here](https://physics.stackexchange.com/questions/443529/where-is-all-the-antimatter) is a link to a recent Physics.SE question on this topic.
PM 2Ring
CC BY-SA 4.0
2018-12-04T08:36:36.810Z
The correct answer is that the origin of matter is currently an unsolved problem, possibly the greatest unsolved problem in physics/cosmology. **Science doesn't know the answer to your question** (for now). There's nothing wrong with "we don't know (for now)" in science.
David Hammen
<big-bang-theory><matter><antimatter>
Why more matter still left after collision with anti-matter?
Rahul Singh
# Why more matter still left after collision with anti-matter?

(Asked by: username_0 on 2018-12-01)

Question implies all, why is that? Why we exist even after equally creation of matter and anti-matter, any possible exception?

**Tags:** big-bang-theory, matter, antimatter

> **Comments:**
> **username_1**: Nobody knows. Perhaps you could rephrase your question? To something like - are there any proposed ideas or mechanisms that might lead to... ?  
> **username_0**: Yeah, I meant to that.  
> **username_2**: Why do you think there was equal creation of matter and anti-matter? The accepted theories do not require this.  
> **username_3**: [Here](https://physics.stackexchange.com/questions/443529/where-is-all-the-antimatter) is a link to a recent Physics.SE question on this topic.  
> **username_4**: The correct answer is that the origin of matter is currently an unsolved problem, possibly the greatest unsolved problem in physics/cosmology. **Science doesn't know the answer to your question** (for now). There's nothing wrong with "we don't know (for now)" in science.  

---

## 1 answers

### Answer by username_5 on 2018-12-02. Score: -3 | Accepted answer

I presume you're asking about the [mystery of the missing antimatter](https://www.google.co.uk/search?q=mystery+antimatter&*&cad=h). This features extensively in the popular and scientific media. For example the CERN webpage on [the matter-antimatter asymmetry problem](https://home.cern/science/physics/matter-antimatter-asymmetry-problem) is fairly typical. It says the Big Bang should have created equal amounts of matter and antimatter, but everything we see today is made almost entirely of matter. It goes on to say *“something must have happened to tip the balance. One of the greatest challenges in physics is to figure out what happened to the antimatter”*.

I think it's something of a "clickbait" mystery I'm afraid, to try to curry favour with the paying public. Why do I think that? Because there’s baryon asymmetry, where we see lots of protons but hardly any antiprotons, and there’s also lepton asymmetry where we see lots of electrons but hardly any positrons. And they *match*. Take a look at positronium. It’s *“a system consisting of an electron and its anti-particle, a positron, bound together into an exotic atom”.* The electron is matter, and the positron is antimatter. Positronium however is neither matter nor antimatter. It’s *both*. It’s an exotic atom. Now see [page 314](https://books.google.co.uk/books?id=Q74GCAAAQBAJ&pg=PA314&lpg=PA314&dq=%22light+hydrogen%22&#v=onepage&q=%22light%20hydrogen%22&f=false) of *photon and electron collisions with atoms and molecules* edited by Philip Burke and Charles Joachain. It says *“the positronium atom thus created is in essence a very light hydrogen atom”*. So positronium is both matter and antimatter, and it’s like light hydrogen.

The clear inference from that is *hydrogen is also a combination of matter and antimatter*. We say the electron is matter, and the proton too. But why? Surely since the proton is more like the positron than the electron, we ought to say the proton is the antimatter. Like this:

[![enter image description here](https://i.sstatic.net/RdUNN.jpg)](https://i.sstatic.net/RdUNN.jpg)

That would mean antimatter is a lot more common than people say. The proton mass is 1836 times the electron mass. Which would mean that weight for weight, 99.95% of everything around you is made of antimatter. Where’s all the antimatter gone? Nowhere. Because it’s hiding in plain sight. Because truth be told and by and large, *you are made of it*.

> **Comments:**
> **username_6**: Since the answer has been accepted, I'll add my explanation for the downvote: This answer is mostly incorrect. Claiming that the electron should be called antimatter doesn't fix baryon *or* lepton asymmetry. This is a personal theory, not science.  
> **username_7**: Right. This is a somehow inspiring answer that doesn't answer the question about what/how an asymmetry is seen. And @username_6★  
> **username_5**: @username_6 : please note that _baryon asymmetry is matched by lepton asymmetry_ is not some personal theory. It's science. As is positronium _“is in essence a very light hydrogen atom”_. Along with the particle properties - the proton is indeed more like the positron than it's like the electron. What _isn't_ science is dismissing the above and peddling mystery instead.  
> **username_6**: @JohnDuffield I have no idea what you mean by that quote. A proton and an electron are not the same thing as a positron and an electron. They're completely different - different masses, constituent particles, baryon/lepton number, etc.  
> **username_5**: @username_6 : positronium is described as "light hydrogen" by various authors. You can [Google it](https://www.google.com/search?biw=1366&bih=626&tbs=li%3A1&ei=O38FXMjrIYbbgAazjb3IAQ&q=positronium+%22light+hydrogen%22+-%22hydrogen-like%22+-duffield&oq=positronium+%22light+hydrogen%22+-%22hydrogen-like%22+-duffield&gs_l=psy-ab.3...20869.22918..23607...0.0..0.54.463.10......0....1..gws-wiz.82p1Q5qk1RE).  
> **username_8**: @JohnDuffield Positronium has been nicknamed "Light Hydrogen" due to it vaguely sharing some similar traits. However, the reality is that any particle-antiparticle pair (an Onium) is not just a light version of a traditional atom. Your answer is simply not correct.  
> **username_5**: @username_8 : there's nothing vague about positronium chemistry, or about the particle properties which tell you that the proton is more like the  positron than the electron, or about the baryon asymmetry being matched by lepton asymmetry. My answer might be unfamiliar to you, but you can't actually point to any actual flaw in it. Saying _your answer is simply not correct_ is no substitute for facts and evidence like I provide. Perhaps you'll only believe what I'm saying once you've seen it in a paper in Nature?  
> **username_8**: @JohnDuffield I was not suggesting that there is anything vague about the physics. In fact, the physics is quite clear. A Positron, like an Electron, is a lepton. It has the same mass as an electron, but has the opposite (+) charge, a trait it shares with a Proton. Protons, on the other hand, are baryons, and are composed of quarks and are orders of magnitude more massive. The only property that is shared between a Positron and a Proton is the charge. This is not enough to claim that they are more alike than a Positron and an Electron are, when the later clearly share vastly more traits.  

---

