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

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Can/will antimatter ever be superior to fusion as a practical electricity source?

I was reading the top answer on this page and I didn't quite understand if the author (presuming the answer is correct) meant a) that fusion was always better, or b) that once we figure out fusion we ...
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3answers
53 views

Do matter and antimatter annihilate or release energy?

Do matter and antimatter eliminate each other or release their equivalent energies? I'm almost certain it's the latter as mass can't be destroyed, but when speaking of the big bang it's said if there ...
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3answers
104 views

How is relativity related to anti-particles?

I have heard that a positron is like an electron moving backward through time. Can someone elucidate this statement for me. I would like to hear a deeper explanation of what we believe anti-matter to ...
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1answer
41 views

Can we extract positrons from gamma rays?

If gamma rays undergo pair production is there a way to say, deflect and collect the positrons using magnetic fields?
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2answers
53 views

Theoretical relativity of black hole and antimatter [closed]

(Theoretically), can black holes be considered antimatter that just cancels its equivalent mass and goes back to neutral stage? Note: Be kind I am not a physicist .
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0answers
20 views

Asymmetry vs. Simple Statistics WRT Matter / Antimatter Ratios

I'm not clear on why physicists suspect, and are looking for, an asymmetry in nature that favors matter over antimatter. Here's a simple thought experiment to illustrate my confusion: Assume I have ...
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1answer
29 views

C&CP-Symmetry Violation in Baryogenesis

In cosmology, during the big bang; how does C-Symmetry violation allow for a greater number of baryons to be produced than anti-baryons in Baryogenesis, similarly how does CP-Symmetry tie into this?
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2answers
65 views

Does anti-matter increase or decrease in entropy over time?

Antimatter is matter going backwards through time. From a matter-based observer does antimatter: Increase in entropy (and therefore decrease in entropy in its own time) OR Decrease in entropy ...
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2answers
33 views

What would the consequences be if it was experimentally shown that antimatter bends spacetime opposite from matter?

This is inspired by another question I found on here about antimatter bending spacetime the "other way." The answers say that physicists believe antimatter will act the same as regular matter in terms ...
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2answers
100 views

What is the most common form of antimatter in the universe?

During our high energy accelerator collisions we are bale to produce antimatter. Processes in the Sun produce positrons. Neutron decay produces anti-neutrinos. Cosmic rays can produce a myriad of ...
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68 views

Are we able to store low energy positrons in a magnetic field for arbitrarily long time?

And if not, what prevents us? Is there a mathematical equation describing the loss rate?
2
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2answers
138 views

What is the mechanism of particle anti-particle annihilation

My question is loaded with assumptions so to minimize them, I would like to ask it with respect to an electron and anti-electron annihilating. When I think of annihilation, I think of electron and ...
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1answer
59 views

Difference between anti-matter and matter black holes [duplicate]

Laymen question: Is there any way to determine by observation whether or not a black hole has resulted from the core collapse supernova of a star originally composed of anti-matter versus a star ...
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1answer
105 views

Could the universe's antimatter be hiding in black holes?

As far as we know almost all the mass in the universe is matter, not antimatter. There are three scenarios: The universe started off with more matter than antimatter and the small amount of ...
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1answer
37 views

What is antimatter and its role in the universe?

As we know everything has its opposite. Like matter its opposite is antimatter. So why the universe is not made by antimatter instead of matter. And what is the main role of antimatter in the ...
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0answers
29 views

Can antimatter becomes black hole? [duplicate]

I know it seems unlikely to accumulate sufficient amount of antimatter to let it collapse under its own weight to become a black hole(maybe the gravity works differently I don't know) since they will ...
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1answer
54 views

Is a matter anti-matter collision comparable to Gamma Ray Burst (GRB) energy output?

Is a matter anti-matter collision (please assume two cosmological objects, neutron star sized say), the largest energy release method known? Would it be comparable in order of magnitude to gamma ray ...
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1answer
30 views

can we see or accumulate antiparticles

I would like to know if we can see antiparticles with our bare eyes instead of a technological detector. I realize we cant see individual atoms or particles but enough photons grouped together, for ...
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2answers
32 views

Neutron antineutron reaction documentation

Has neutron-antinutron reaction been observed? If so, can you please provide a documentation (experimental observation) for neutron antineutron reaction?
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2answers
89 views

Sign of momentum in fermion propagator

Thinking of a process like Compton scattering, where we have an electron as a propagator, I would typically write down the propagator as $$i \frac{\not q+m}{q^2-m^2}.$$ If I were to replace the ...
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1answer
30 views

Similarity between particles and antiparticles

I was doing a past exam paper and there was this question: State the similarities between a particle and its antiparticle. The answer given was: Same mass and rest energy. I am not too bothered ...
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1answer
355 views

Is the virtual photon a particle?

I just saw an exam question: Write down the antiparticle for the virtual photon. The answer was "virtual photon". Is the question even a meaningful one? If so please explain why?
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3answers
75 views

Does (mass $\rightarrow$ pure energy) conversion need both matter $and$ antimatter?

A question in my revision guide: "Explain why the mass of a tree cannot be converted directly into energy." The answer explains that the tree contains particles but not their corresponding ...
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5answers
3k views

Will 1 gram of matter moving at relativistic speeds completely annihilate a larger quantity of stationary antimatter?

This is a question about the relativistic mass concept which I am having trouble understanding, mainly because of the scenario below. Simple scenario: Suppose 1 gram of matter is accelerated to 99% ...
3
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3answers
101 views

Decay of matter

I was watching Stephen Hawking's documentary and in there he explained how he realized why black holes eventually disintegrate: There are ripples in space, an antiparticle and a particle get ...
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2answers
79 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
65 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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2answers
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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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1answer
70 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
42 views

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

If not, what is the roadmap for the first Antimatter experiment in outer space?
3
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1answer
305 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
47 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
78 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
239 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
38 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 ...
2
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1answer
37 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 ...
2
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0answers
74 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
138 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
27 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
89 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
118 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
265 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
53 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
34 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
106 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 ...
3
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4answers
93 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
285 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
74 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 ...