Questions tagged [matter]
The matter tag has no usage guidance.
375
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In the Big Bang theory which came first, the vacuum or matter? [closed]
Simply what is our best estimation of what came first in the the first fraction of time of the BB? Was it the vacuum and then matter popped out from violent quantum vacuum fluctuations or matter then ...
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In order for Sound to exist, are Spacetime, Matter & Motion required first, in that exact order?
From what I’ve read so far online, briefly reading Newton, Einstein, and Minkowski’s theories this is the order I’ve come to. I.e, for matter to exist first there has to be space and time, for motion ...
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Does a lump of baryonic matter have a well-defined particle number?
From reading about quantized electromagnetism, it seems that many forms of light (e.g. lasers) don't have well-defined numbers of photons, or in other words are superpositions of different number ...
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2
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Matter and Antimatter coexistence [closed]
Isn't it possible that matter and antimatter coexist? Recently, the ALPHA experiment at CERN has been looking into this topic. And I read about it from Fermilab's website, so they are saying how our ...
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Is matter in space, or independent from it, but interracts?
Considering the "hierarchy" of the Universe, or the world in a broad sense, as I understand it consists of matter, matter consists of "substance" (fermions), and fields and so on.
...
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What happens to metals and ceramics under high hydrostatic pressure?
What would happen to metals or ceramics (non-porous) when subjected to extremely high pressures (dozens of GPa) ?
I feel like the sample will deform elastically only. So a ceramic object (think ...
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How would I understand Hysteresis from scratch? [closed]
I wanted to learn about Hysteresis and I know the basic undergraduate level of 'Mechanical properties of matter".
Can anyone please help?
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Event after big bang that cause dark matter [closed]
When the universe was formed by the Big Bang, what was the event that made some matter visible to us, while some became dark matter?
3
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Does the event when two BH without polar jets merge, cause a short living polar jet on the newly formed BH?
Does the event when two BH without polar jets merge, cause a short living polar jet on the newly formed BH? As BH need infalling material to activate their polar bursts does the BH falling into ...
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What happens to matter at extreme temperatures?
Water at absolute zero is, I suppose, ice. At room temperature it's water. At a certain point steam. What happens to it as we approach infinite temperature? (what we might call "absolute" ...
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2
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What earthbound experiments show gravitation is general to all matter, and not just towards the earth?
I was debating a flat earther and predictably it turned into a debate on gravitation. He said as far as we know, things fall down to the earth, not because its towards the greatest mass. The ...
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Does CP symmetry dictates that a particle and its antiparticle behave the same when moving in opposite directions and how can I observe CP asymmetry?
I have started reading in particle physics very recently. I have been reading a bit about tau particles, and I came across the idea of CP symmetry and how it’s violation may present an explanation for ...
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If the electromagnetic force did not exist before it froze out, how could there have been a meaningful distinction between matter and antimatter?
If electrons and positrons are identical except for their opposing charges, what was the nature of these particles before the EM force separated out?
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3
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Physical Significance of Frequency of matter waves
So, in our book there was an additional exercise part and this question baffles me:-
Q. Answer the following questions:-
The energy and momentum of an electron are related to the frequency and ...
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2
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178
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Are the Einstein field equations the Equations of Motion for matter?
I'm learning general relativity and eventually I hope to understand the Einstein field equations $$G_{\mu\nu}=\kappa T_{\mu\nu}$$ in full mathematical detail.
I wonder whether they describe the ...
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2
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Mass matter, energy and "massless matter"
This is perhaps a rather silly question, or rather a matter of convention, but I would like to hear arguments about the appropriateness of certain definitions.
Traditionally, in chemistry and in pre-...
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Can some regions of space (independent of size), be completely devoid of matter?
Before answering the question, keep in mind that I am a second year Biology student, with no experience in studying Physics and a very basic understanding of Mathematics. However, I have some ...
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2
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How does some matter prevent other matter from reaching a lower potential energy state?
Before answering the question, keep in mind that I am a second year Biology student, with no experience in studying Physics and I consider myself 'mathematically illiterate'.
An example of matter ...
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1
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334
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How would the universe look like without matter?
I was wondering how the universe would look like if it would have been perfectly symmetrical in terms of matter and antimatter. If I understand correctly, there would be no "particle" but ...
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2
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Why is all matter in the universe, not found at its lowest state of potential energy?
Preface: it may be of interest that I am a second year Biology student, with no experience in studying Physics and a very basic understanding of Mathematics. ...
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2
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Why does de Broglie wavelength work?
The equation is $\lambda=h/(mv)$.
I am currently learning electron diffraction and have learnt about how de Broglie studied on the wave-particle duality of matter such as electrons.
We were given the ...
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Expansion of the Universe inside mattar [duplicate]
When talking about the expansion of the universe we usually refer to the Friedman equations so we assume homogeneous and isotropic solution to Einstein field equation which is true on cosmological ...
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Gravitational interaction between antimatter particles [duplicate]
Is there some positron-positron collision experiments?
Is the gravitational interaction between antimatter particles the same as between ordinary matter particles?
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45
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Have physicists ever consider the possibility that if spacetime can be crumpled the crumpling itself CREATES matter? (I'm not a physicist) [duplicate]
This following example explains my question. Let's take a spread out bed sheet, which represents spacetime. At the center of the bed sheet, I start to crumple/wrap the fabric of the bed sheet. The ...
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Why can gases pass through each other while solids cannot?
Solids cannot (generally speaking) pass through each other, while gases can. The first answer to this question points to the electromagnetic force and the Pauli Exclusion Principle as the reasons that ...
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Calculating the Miller Indices for the Crystal Structure of Graphite
I am currently completing a lab project on X-Ray Crystallography where I am investigating the crystal structure of graphite.
We are given this relation (1) between the lattice constant $a$ and the ...
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2
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110
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Spin of electron and photon emitted
How does the spin state of the electron affect the polarisation of the light emitted?
I am looking for a description in a detailed mathematical aspect, any suggestions on books ?
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How do you get energy from matter with 100% efficiency?
Using $E=mc^2$, how can you make some energy from matter 100% efficiently?
For example, if I gave you about 1 kg of mass you could get a whopping (9*10^16) joules of energy with 100% efficiency. The ...
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Does atomic particles have smell? [closed]
Do atomic particles like Sulphur or Hydrogen have their own distinct smell? Is the distinctive smell of Hydrogen Sulphide a combination of the smells of Hydrogen and Sulphur ? If not, then how do ...
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53
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Is a Torricellian vacuum a perfect vaccum(devoid of any kind of matter)?
Is a Torricellian vacuum as such in a mercury barometer a perfect vacuum i.e. is it devoid of any kind of matter? If not , then what does it contain and why?
As a 9th grade student , it is mentioned ...
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"Lateral Extension" of a matter wave
This question may be stupid, but I would be very grateful for an answer. As far as I understand, a matter wave has a wavelength and an amplitude. The amplitude does NOT extend in space, it simply ...
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Does Black Hole requires a material medium to be formed?
Does Black Hole requires Material medium to be formed or it can be formed without any medium (Vacuum)? as anything which can be thrown with the speed of light can form a Black Hole and light can also ...
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Has spacetime some physical properties?
"Spacetime isn't a physical object, it's a mathematical structure (manifold with metric) that tells us how to calculate the distance between objects, so matter can't slide over spacetime."
(...
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2
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Does anyone really know how dark energy/matter works?
If dark energy has no physical interaction with normal matter but it does interact with dark matter, wouldn't that cause an interaction with normal matter through its interaction with dark matter and ...
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1
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77
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Why not say a scalar potential as a function representing the matter itself? [duplicate]
[Question] Why not say a scalar potential as a function representing the matter itself?
At first glance, this idea seems to make the duality, which is the biggest difficulty in understanding quantum ...
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2
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If there was an infinite amount of matter at big bang to form an infinite universe how it was possible for a so huge amount of matter to expand?
If there was an infinite amount of matter at big bang to form an infinite universe how it was possible for a so huge amount of matter to expand? Is it better to think that the universe is spatially ...
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Mass defect and macroscopic phase transitions [closed]
Will there be a mass defect of a water 1kg boiling into vapour? When the vapour is turned back into water, do you think there will be a mass defect or we get the same mass?
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3
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If the universe was dominated by antimatter instead of matter, would we physically notice?
I read that antimatter and matter are identical aside from their opposite charge and quantum number. Of course, the mystery of why matter dominates in our universe is an active field of research. But ...
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2
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393
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Matter-antimatter and annihilation
In this question, it seems posed how a particle and its anti particle can get close to each to annihilate. One answer proposed that "The force involved in annihilation is normally either the ...
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For an auxetic solid, what is the relationship between the Shear modulus and the Young's modulus?
I know that for an isotropic solid, G = Y/2(1+v) but not sure if it is the same for an auxetic solid?
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What is matter and what is mass?
In classical physics and general chemistry, matter is any substance
that has mass and takes up space by having volume. (Wiki)
Fair enough, so what is mass?
Mass is the quantity of matter in a ...
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How do electron acceptors and donors affect molecular geometry?
I'm currently working with two molecules: Ethylene $CH_2CH_2$ and $CH_2CHCH_2$ (whose name I don't know).
The question is how does doping them with an electron acceptor/donor affect their geometry?
My ...
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Does the Schwinger effect prove matter and antimatter can be created from a vacuum?
Virtual particles or vacuum fluctuations are the pair annihilation/creation of matter and antimatter particles in and out of the vacuum. Theses particles are virtual, but we know they exist because of ...
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Matter is Apparently just Field Excitations, But How the Heck does that Work? [duplicate]
Ok so, around four-ish months ago, I was told by a Cosmologist that what we perceive as matter doesn't actually exist and that the alleged particles that we think it's comprised of are actually "...
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Why is the energy density of the dark energy component~magnitude as the density of matter now, when the two evolved in different time periods?
WMAP determined that the universe is flat, from which it follows that the mean energy density in the universe is equal to the critical density (within a 0.5% margin of error). This is equivalent to a ...
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Does Einstein stress-energy tensor represent spacetime or matter?
I am writing a paper entitled "On static solutions of Einstein's field equations for fluid spheres". I assume there a diagonal stress-energy tensor, $T_{\mu}^{\nu}=diag~\{\varepsilon,-p,-p,-...
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Could the hypothesis of regular matter converting into dark matter help to find out what the dark matter is? [closed]
Could the hypothesis of regular matter converting into dark matter (Dark Matter from Exponential Growth, free version available from the arXiv with a rather different title) help to find out what the ...
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76
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What are the conditions needed for baryogenesis? [duplicate]
Physicists have created antimatter in the laboratory. But when they do, they create an equal amount of matter. That suggests that the Big Bang must have created matter and antimatter in equal ...
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Why do matter and radiation densities scale differently in expanding universe, when all matter is energy and all energy is matter? [duplicate]
I sometimes see the first Friedmann equation expressed with different terms for the density of "matter" and the density of "radiation". It is said that with an increase in scale ...
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How the universe is expanding? [duplicate]
If universe is expanding with the velocity of light then why the distance between earth and sun is constant? Also why the distance from one Galaxy to another remains constant? And so on...