Analogous to matter, but with charge of the particles opposite to their ordinary matter counterparts.

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54 views

Could the missing antimatter lie outside the observable universe?

While I was reading a similar question asking if other galaxy could be made of antimatter, to which the answer was: if they were, we should detect the radiation from matter interacting with antimatter ...
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2answers
30 views

Is every aspect (fundamental forces, periodic table) of an antimatter universe exactly the same, except the fact that it's all antimatter?

Are all the constants (Boltzmann's, gravitational, $c$) the same? Would elements react differently? Would it look the same?
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68 views

Questions about the strange character of antimatter

Its been a few days and i have just been introduced to the concept of antimatter. Every Speck of matter in the world has its anti form basically that we have antimatter whenever we have matter. But I ...
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0answers
34 views

Is it possible to power a black hole with an antimatter engine? [on hold]

I'm curious about using an antimatter engine to power a black hole and vice versa, can anyone enlighten me please? I'm new to this way of thinking but I have read some bits online and I keep getting ...
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1answer
37 views

Charge conservation in the complex Klein-Gordon Field

This is an extremely naive question (based on a knowledge of chapter 2 of peskin and schroeder) so apologies for any things that seem obvious. The complex scalar field, when quantized, has a conserved ...
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1answer
38 views

Has the human race ever done Antimatter experiments in outer space (e.g. on the ISS)? [on hold]

If not, what is the roadmap for the first Antimatter experiment in outer space?
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1answer
278 views

Antineutron repelled by gravity?

I was reading an old post, Can gravity be shielded, like electromagnetism?. One of the responses had this comment. There are some experiments trying to measure whether antiprotons ( antimatter) ...
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2answers
41 views

On Elementary Particles

The mass of positron and electron are same. Also their charges are equal in magnitude but opposite in nature. Then why positron is not called one of the elementary particles? Is this only because it ...
2
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1answer
60 views

Pair-annihilation why does it occour? [duplicate]

Why does pair annihilation occur with particles and only their matching anti-particle? E.g., electrons and positrons, but not protons and positrons? What is the difference?
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1answer
160 views

How can anti-matter annihilate matter?

I heard that anti-particles annihilate when in contact with normal-particles but the odd thing is that in fusion reaction normal-particles often "fuse" into each other but the weak force often ...
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0answers
31 views

Do quasiparticles have antiparticles?

Bosons (except for W) are their own antiparticles, since they have no electric charge. Charged fermions have antiparticles differing from the particles. Now my question is: has a charged ...
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1answer
32 views

Proton creation [closed]

My question is simple: if proton antiproton pairs can be created in the laboratory (given certain energies) then they should also be able to be created in the universe at any time, not only during ...
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0answers
62 views

Antimatter universe and Noether's theorem

I am studying Feynman's "symmetry in physical laws", where he talks about conservation laws for corresponding symmetries. (I know this is Noether's theorem, I am studying this from David Tong's ...
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3answers
105 views

Quark anti-quark pair creation. Do we need a gluon?

What is the difference between these diagrams? Is the presence of the gluon taken for granted in the second one? and EDIT: I just zoomed into the picture, it is not a single quark state. ...
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0answers
23 views

Antimatter production using normal matter rest mass

Antimatter could be produced by inverse annihilation from kinetic energy of particles. This is, however, not useful to produce any energy. Is there any pathway (like set of reactions between sub ...
2
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1answer
72 views

Charge operator for Dirac spinor

In QED, the gauge transformation which acts upon a fermionic field $\psi$ is $$\psi'(x)= e^{i \alpha(x) Q}\psi(x)$$ where $Q$ is the charge operator. Most of the time it's just written as $$\psi'(x)= ...
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1answer
91 views

Theory of black holes producing matter or antimatter [closed]

One of my friends gave a theory about the formation of black holes. He said that: Black holes are formed when an extremely massive star collapses in its own gravity to produce a particle of ...
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4answers
2k views

Could we make things out of newly discovered particles?

Right now, all of the "stuff" that has been created in the world is made of protons, electrons, and neutrons. I'm aware that particles other than these have much shorter lifetimes. But I've also heard ...
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4answers
230 views

What is antimatter?

Can you give a visual example of what is antimatter? With the re-opening of Large Haldron Collider scheduled in Mar 2015, I'm reading that they smash two particles together to try to re-create ...
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2answers
46 views

How are positrons produced? [closed]

What are the methods of positron production? Please don't use mathematical formulas in the explanation.
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0answers
30 views

Antimatter traveling back in time and gravity [duplicate]

I've been reading on the construct of considering antimatter as matter traveling backward in time, which seems like an useful tool. There seems to be some discussion around this concept, if ...
3
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1answer
103 views

Light in a box with positron walls instead of electrons

I understand that with a hollow cube with the inner walls covered in mirrors given a light source briefly, the light would eventually be absorbed. This is due to electron excitation I believe. So ...
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4answers
83 views

Can antiprotons make stable bounds with halogens?

Halogens are known for being highly electronegative. That means their electron dipole moment are high enough that they want to share other atoms electrons. I'm wondering If two Halogen atoms could ...
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2answers
191 views

Feynman-Stueckelberg interpretation

My question is related to the interpretation of antiparticles. According to the so called Feynman-Stueckelberg interpretation a negative energy solution of the Dirac equation corresponds to a positron ...
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2answers
65 views

Can antimatter-matter collisions generate heat?

We have a project at school to develop an idea about how we can generate electricity. My question is: do collisions between matter and antimatter particles generate heat, so that one could harvest it ...
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3answers
355 views

Are there really left-chiral particles?

A chiral eigenstate is always a linear combination of a particle and an antiparticle state and a particle or antiparticle state is always a linear combination of chiral eigenstates. Now, how can we ...
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3answers
76 views

What did Skobeltsyn publish about the possible existence of the positron?

I've read across several sources that before C. Anderson discovered the positron in 1933 there were evidence of its existence pointed out previously by C.-Y. Chao and D. Skobeltsyn. After some rearch ...
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1answer
31 views

What happens to K.E. in matter antimatter annihilation?

If I have two matter and antimatter particles, say an electron and a positron, each moving towards each other with a certain speed, they annihilate after the collision. Does the energy of the photons ...
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2answers
189 views

How can we differentiate between matter and antimatter? [duplicate]

For instance if there was a galaxy, assume it to be made up of antimatter (isolated from other "normal" galaxies), how would we, or rather, would we be able to distinguish if it was made up of matter ...
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1answer
51 views

Why are we still living if matter and anti-matter annihilate each other? [duplicate]

Everyone knows matter and anti-matter annihilate each other . But still do we are alive . How? Is the statement wrong?? I am a layman and a novice to QM but will appreciate a math-free intuitive ...
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2answers
113 views

Will Positron Cause flow of electricity?

Recently someone told me about antimatter. Antimatter is something that is completely opposite to matter. What I would like to know is let's say this universe was made of Anti-Matter. So since the ...
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1answer
44 views

If matter and antimatter were produced equally during the big bang, where is the rest of the antimatter? [duplicate]

As far as my understanding goes, during the 'Big Bang' equal amounts of matter and antimatter (matter's oppositely charged twin) were produced, and the physical matter that remains within this ...
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1answer
83 views

Why is the mass of a particle different from its antiparticle?

Like, for example, the neutrinos and the $B_0$ and the $\overline{B}^0$ mesons?
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1answer
1k views

How would one detect antihydrogen in the universe?

Since the spectra of hydrogen and antihydrogen are the same, how do astronomers know which one they're detecting? Is, perhaps, the Lamb shift in antihydrogen different?
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1answer
38 views

How is anti-hydrogen captured?

Knowing that the overall charge is zero, what mechanisms/technologies are used to capture anti-hydrogen? Where is it stored until annihilation? I am aware of magnetic traps being used to edge the ...
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2answers
616 views

How is antimatter made?

How is antimatter made in laboratory? Can anyone explain, at the particle level, specifically how anti-protons and anti-electrons are made?
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1answer
107 views

How the neutron magnetic moment was measured?

How was the neutron magnetic moment measured? Was the antineutron magnetic moment measured too?
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1answer
1k views

Is there any antimatter that exists as atoms?

I recently read a few things that implied that there is antimatter that we know of (have created?) that exists as atoms - which I guess means positrons and antiprotons bound together, at least. Is ...
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3answers
938 views

Has the gravitational interaction of antimatter ever been examined experimentally?

I know that the gravitational interaction of antimatter is expected to be the same as normal matter. But my question is, has it ever been experimentally validated? I think it would not be a trivial ...
6
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2answers
329 views

How detectors in particle colliders can differentiate neutrons from antineutrons?

Their mass is the same. None of them interacts with EM fields. And their decay (around 1000s) is far too slow to see their decay products yet in the detector. How is it then possible to differentiate ...
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1answer
40 views

What underlying structure/framework defines the charge of an antiparticle or regular particle (specifically a proton)? [duplicate]

I can't seem to find an answer to this. For a given configuration, say for a Hydrogen atom: the proton has properties which give it a positive charge. This is a known truth. Now lets take Hydrogen's ...
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2answers
65 views

Is it possible for larger antimatter atoms to decay to matter and visa versa?

Following on from previous questions: If you have antimatter-matter interactions where there is a larger antimatter particle (say carbon or Silicon), is there any reason to believe that the ...
3
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1answer
150 views

Have there been attempts to create heavier antimatter particles?

This is a follow-on from previous question: It seems as though all experiments concerning antimatter have only been conducted with antimatter protons - as they are obtainable through decay. Have any ...
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2answers
111 views

What happens when Antimatter interacts with a photon?

So... I was just pondering the energy and particles in the universe. It makes sense that matter is attracted to it's self by a gravitational force - it clumps and forms some kind of gravity ...
2
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1answer
83 views

Electron/positron annihilation lines in astrophysics

I have a reasonable understanding of electron/positron annihilation, in that it is a collision between a pair of particles, one matter and one antimatter, that generally produces gamma radiation. ...
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1answer
194 views

Is it possible that our universe is oscillating between matter and antimatter at a high frequency? How would we know? [closed]

Suppose the big bang did create equal portions of matter and antimatter and they exist right over top of each other, such that there is a constant inversion going on. Since a matter and antimatter ...
2
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2answers
162 views

What's the symbol for the antiparticle of the delta plus baryon?

It can't be $\Delta^-$ since that is another particle also made up of quarks (not antiquarks). I can think of four possibilities: $\overline\Delta^+$ $\overline{\Delta^+}$ $\overline\Delta^-$ ...
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3answers
522 views

Anti-neutrons, anti-quarks, isospin: What is observed and what is derived?

I would be a little more restrained with the existence of antineutrons. First at all - if I understood right - the existence of antiquarks is hypothetical. If one not agree with this please refer to ...
3
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1answer
309 views

Matter and antimatter differences?

I've heard (and after googling for a while, found) that the only difference between matter and anti-matter is simply charge. This bothers me when it comes to the neutron. Matter and anti-matter ...