Questions tagged [matter]
Use this tag for questions related to mass and any materials that have volume and the objects they constitute.
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What distinguishes the particles we chose as matter from their antimatter equivalent? [duplicate]
Back before we knew about antimatter we just called everything matter. Ignoring CP-violation for a moment, there is nothing special about matter versus antimatter.
Once we knew about antimatter it ...
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What is negative Energy/Exotic Energy?
So I have been researching around a little as I am highly interested in Astrophysics and I came across an energy I have never heard of before; negative energy also commonly known as exotic energy. Now ...
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Feynman Diagrams: Mass Conservation
Can a Feynman diagram end with more matter than it began with? The answer should be no because it would break the law of conservation of mass, right?
Example:
I learned that two up-quarks could ...
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X-Ray/Gamma Ray shielding: density versus conductivity
When talking about gamma ray or x-ray propagation in media, we usually talk about the mass attenuation coefficient, and we desire high density materials for shielding. This seems probabilistic: we ...
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Are matter waves transverse and can they be polarized?
Are matter waves transverse and can they be polarized?
What I know:I'm aware of the de Broglie matter waves hypothesis and de Broglie wavelength relation(at a very basic level as part of high school ...
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Where does the rubber go when a tire wears down? [closed]
Every year millions of car tires are worn down on our highways, yet the roads are not all black from the rubber, neither are the sides of the roads black. Where does all the rubber go?
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Is matter a continuous part of the field of space-time? [duplicate]
I recently found this quote by Einstein (in On the Generalized Theory of Gravitation, 1950), and it seems to me like he is saying that matter is a part of the field of space-time, and is nothing more ...
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How do we know Dark Matter is non-baryonic? [duplicate]
It seems widely stated, but not thoroughly explained, that Dark Matter is not normal matter as we understand it. Wikipedia states "Consistency with other observations indicates that the vast majority ...
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When does 'energy' turn to matter?
I always hear about matter converting to 'energy' - fusion, fission.
When does it go the other way around? What conditions lead to it? Are there reproducible experiments on this topic?
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Creation of matter in the Big Bang
I appreciate your patience to my neophyte question. I am working on my dissertation in philosophy (which has nothing or little to do with physics) about the "problem of naming." Briefly what ...
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Why does space expansion not expand matter?
I have looked at other questions on this site (e.g. "why does space expansion affect matter") but can't find the answer I am looking for.
So here is my question: One often hears talk of space ...
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Why isn't dark matter just ordinary matter?
There's more gravitational force in our galaxy (and others) than can be explained by counting stars made of ordinary matter. So why not lots of dark planetary systems (i.e., without stars) made of ...
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