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Breakthrough Junior Challenge
Course: Breakthrough Junior Challenge > Unit 1
Lesson 3: 2015 Challenge — Physics- Special theory of relativity - 2015 Challenge Winner!
- A visualization of special relativity
- Chromatic aberration
- Orbital mechanics
- What is light?
- Special and general relativity
- The science of fireworks
- Quantum tunneling
- Antimatter
- Special Relativity
- What Einstein missed: The EPR paradox
- Virtual particles and gravity
- Interstellar and Hawking radiation
- All about superconductors
- Entropy and the direction of time
- Magnetism, light and the magneto optic Kerr effect
- The theory of everything
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Antimatter
By Parker Ruth
“Antimatter is a weird topsy-turvy shadow of matter, like tweedledum to ourtweedledee real
“Antimatter is a weird topsy-turvy shadow of matter, like tweedledum to our
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Why is it that the electron and positron, though differing only in charge, annihilate each other instead of forming a neutral particle?(10 votes)
You are true. But remember that E=Mc^2 and energy that is created is neutral just as
+1 + (-1) equals 0. In the same way, they form energy and energy and matter are same. Hence your neutral particle and the annihilation which causes the energy is the same.(5 votes)
Uh, don't both an anti neutron and a neutron have the same charge(neutral)? Why do they still annihilate each other?(6 votes)
Originally, antimatter was defined as matter with an opposite charge but otherwise the same particle, as described in this video.
However, antimatter is matter with an opposite property, not limited to charge, but otherwise the same particle. An antineutron has the same mass and all other properties of a neutron except for a Baryon Number, which is another property of particles. The neutron has +1 baryon number, while the antineutron has a -1 baryon number.
See: https://en.wikipedia.org/wiki/Antineutron(6 votes)
How do we know we're not in an antimatter universe?(5 votes)
We are in an anti mater universe. This universe has both, mater and anti mater. And if you look at things from the perspective of the anti mater, we are the "anti" of them. Course this goes back to relativity.(2 votes)
- According to scienctists, equal antimatter and matter would be created in the big bang, so why didn't they destroy each other?(6 votes)
- The individual particles did not have the same momentum vectors. Granted, the wholes of mater and anti mater were equal and opposite, just the individuals were not, so they did not cancel each other out right away. In other words, they did not come in contact with one another.(1 vote)
How would one create antimatter? Or is it just there and unable to be made?(2 votes)- Anti matter can be created with the help of large hadron collider other wise in nuclear chemistry you might have read about positron emission like
C 14------->N 14 + positron. There are even more methods but simplest method is radio active decay(2 votes)
What is a negatively charged proton called?(0 votes)
at6:22why we have to create matter with anti matter to work out with
can not we use matter around us?(1 vote)- At6:30, why do we end up back to where we started when all of the particles are annihilated? Aren't the collisions supposed to generate much more electricity than the starting masses worth?(1 vote)
Remember the law of conservation of energy: energy can be neither created nor destroyed, but can only change forms. What happens here, is that energy frozen inside of particles is released as a photon, but the amount of energy can't change, it can only take on a different form. A ton of energy is released, but it is not created.(1 vote)
In PET, they told that positron are used to detect defects and this happens because the positron annihilates with electrons that gives out high energy photons. Won't this huge amount of energy affect our body in anyway? It's really a very huge amount of energy!(1 vote)
m=2g? when matter is 1 g and anti matter is 1 g as well, then anti matter ,which is supposed to be a 'negative' must cancel out matter ,which is positive and hence we must end up with 0 ,right?(0 votes)
6:22