In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic particles, and in everyday as well as scientific usage, "matter" generally includes atoms and anything made up of them, and any particles (or combination of particles) that act as if they have both rest mass and volume. However it does not include massless particles such as photons, or other energy phenomena or waves such as light. Matter exists in various states (also known as phases). These include classical everyday phases such as solid, liquid, and gas – for example water exists as ice, liquid water, and gaseous steam – but other states are possible, including plasma, Bose–Einstein condensates, fermionic condensates, and quark–gluon plasma.Usually atoms can be imagined as a nucleus of protons and neutrons, and a surrounding "cloud" of orbiting electrons which "take up space". However this is only somewhat correct, because subatomic particles and their properties are governed by their quantum nature, which means they do not act as everyday objects appear to act – they can act like waves as well as particles and they do not have well-defined sizes or positions. In the Standard Model of particle physics, matter is not a fundamental concept because the elementary constituents of atoms are quantum entities which do not have an inherent "size" or "volume" in any everyday sense of the word. Due to the exclusion principle and other fundamental interactions, some "point particles" known as fermions (quarks, leptons), and many composites and atoms, are effectively forced to keep a distance from other particles under everyday conditions; this creates the property of matter which appears to us as matter taking up space.
For much of the history of the natural sciences people have contemplated the exact nature of matter. The idea that matter was built of discrete building blocks, the so-called particulate theory of matter, independently appeared in ancient Greece and ancient India among Buddhists, Hindus and Jains in 1st-millennium BC. Ancient philosophers who proposed the particulate theory of matter include Kanada (c. 6th–century BC or after), Leucippus (~490 BC) and Democritus (~470–380 BC).
If it were possible to obtain absolute zero, could relativistic matter exist when classical momentum would be zero? Would a particle cease to exist? I can't do the math. Thank you for reading my question.
The likelihood for dark matter appears to be lessening in direct detection and in its utility in explaining astronomical anomalies. With regard to the former, a trio of recent dark matter detection experiments (LUX 2016, PandaX II 2017 and Xenon1t 2018) have all failed to show any non-baryonic...
Summary:: I've written a song based on a lecture I attended re: the universe. I'm hoping to confirm facts re: Dark Matter, etc. discussed within the song.
I have a somewhat unusual request:
I have written a song based on a lecture I attended re: the universe. Before recording and releasing...
Flat rotation curve in galaxies is determined by observing neutral hydrogen which is co-distributed with dark matter. What is the rotation curve profile of neutral hydrogen in galaxies where there is less dark matter?
Bio-impedance technique is used to monitor various organ related qualities. Shift in metabolism will also show up as a shift in impedance. My question is if by exposing a target volume with ionizing radiation and thereby release electrons and at the same time measure the impedance (which will...
Hello!
I am suspossed to find the extreme values of this function
$$f(x,y) = x^3 +3x^2y+3y^2-6y $$
First thing I did is I found all the partial derivations and set them to 0.Since that has to be true for the extreme value to even exist.
The derivations look like this
$$ f_x = 3x^2+6xy $$
$$...
Hello. I'm posting here for the first time. I have a few related questions about matter, dark matter and elements for which I have not been able to find answers.
Does dark matter 'hold' matter in the universe in place? Does matter 'hold' the elements of the universe in place? Does matter create...
https://www.medrxiv.org/content/10.1101/2021.06.11.21258690v1
doi: https://doi.org/10.1101/2021.06.11.21258690
Full PDF (32 pages) at:
https://www.medrxiv.org/content/10.1101/2021.06.11.21258690v1.full.pdf
Do we notice any significant difference in distribution and dynamics of dark matter in galaxies when n-body simulations are done with high or low-mass dark matter particles?
Hi guys, I'm a rising Junior in physics. I would really like to pursue an applied physics PhD
program to study photovoltaics, likely something to do with nano-photonics. My problem now is that I'm
a research assistant in a condensed matter experiment lab, focusing heavily on spectroscopy.
Will...
From a previous post about the Relationship between the angular and 3D power spectra , I have got a demonstration making the link between the Angular power spectrum ##C_{\ell}## and the 3D Matter power spectrum ##P(k)## :
1) For example, I have the following demonstration,
##
C_{\ell}\left(z...
There are reports that our cosmological models can't explain our up to date dark matter distribution maps, and that it calls general relativity into question.
https://www.bbc.com/news/science-environment-57244708
I guess the relevant publications can be found here...
Let's say that it turns out that Dark Matter is realllllly dark. And (except for gravity) none of our experiments actually result in any Matter/DM interactions at all. Not now, not for the next couple of centuries.
Just based on gravity observations, are there things that we will eventually...
Is the physics of living matter different from that of non-living matter? If yes, how it is different? What makes it different? Does biophysics present itself as an example of interface between quantum and classical physics?
Any information that you think might shed light on the subject will be...
This paper suggests that macroscopic dark matter could leave a trail of ionized plasma as it passes through the Earth's atmosphere. If this happens during a thunderstorm it could trigger a lightning strike that follows that trail.
https://journals.aps.org/prd/abstract/10.1103/PhysRevD.103.063024...
Is the Reduced Planck Constant the minimum frequently/movement/spin matter can have to exist?
So if a matter were to spin lower than 1.054 571 817... x 10-34 J s, it when cease to exist?
Or would matter falling below the Reduced Planck Constant by classified as Dark Matter?
I heard that Higgs...
I'm taking a geophysics class and the math makes sense but the context is lost on me. My understanding is that the primary use of seismic ray-tracing is to locate disturbances that cause waves to propagate radially. I also understand that 35km is the depth at which the Earth's spherical shape...
Hello. Questions: Are antimatter, dark matter, negative mass confirmed that they exist and exhibit as phenomena? What about dark energy and negative energy? Do these types of matter behave as wave also? Do they exhibit such behaviour? About those types of energy i said, can they be transformed...
this paper,
Testing the Strong Equivalence Principle: Detection of the External Field Effect in Rotationally Supported Galaxies
Kyu-Hyun Chae1
, Federico Lelli2, Harry Desmond3, Stacy S. McGaugh4, Pengfei Li4, and James M. Schombert5 Published 2020 November 20 claims a 4 sigma...
I'm not sure if this paper belongs in GR or astrophysics but
This articleG. O. Ludwig (2021), Galactic Rotation Curve and Dark Matter According to Gravitomagnetism, European Physical Journal C 81:186, DOI 10.1140/epjc/s10052-021-08967-3
there's no need for dark matter,as GR's Gravitomagnetism...
Hi,
I don't want to be too specific here, but specific enough for relevant advice.
I'm finishing a Masters in Physics and am lucky to have been made offers by 2 excellent institutes: a Max Planck Graduate Centre (MP), and at Oxford UK. Both are in experimental condensed matter; Weyl...
A new pre-print makes a sensible and convincing, in my view, argument that phenomena attributed to dark matter are not exclusively or predominantly explained by primordial black holes formed at less than the mass of a star shortly after the Big Bang, by means other than stellar collapse. This...
This is going to be a rather simple question about the understanding of covalent bonds.
Let's take the simplest molecule - H2 which is gas.
According to quantum mechanics, the two atoms in the molecule each share 1 electron with the other atom and those 2 electrons exist in the form of...
I would like to understand if matter accumulates into the gravity well of the Earth?
After so many years of circling the sun I have this imagination of tritium, nitrogen, and ozone accumulating underneath the Earth into it's traditional orbit, and accumulating over time.
Is this possible and...
In ΛCDM, H(t0) = 70km/s/Mpc,
Ωd(t0) = 0.3, Ωr(t0) = 0 and ΩΛ(t0) =0.7,
so that Ω(t0) = Ωd(t0) + Ωr(t0) + ΩΛ(t0) = 1and the universe is spatially flat.
I want to know the t and z when the matter density equal to the vacuum energy density. By total energy density equation, I think Ωd(t) +...
a) For a flat universe ##(k=0)##, so ##(1)## simplifies to ##\dot a^2 = \frac{C_r}{a^2}##. The solution to this first order, separable ODE (given the I.C. ##a(0) = 0##) is
\begin{equation*}
a(t) = \left( 4 C_r\right)^{1/4} t^{1/2} \tag{2}
\end{equation*}
We switch to conformal time by...
In some textbooks it is given that -
Electric charge is the characteristic property of matter that causes it to experience a force when placed in an electromagnetic field.
and In other textbooks it is given that -
Electric Charge is the property of subatomic particles that causes it to...
Baryon number is, despite all guesses and searches, known to be conserved in all interactions. It is also known to be significantly nonzero, though modest, for world.
Lepton number is, despite all guesses and searches, known to be conserved in all interactions. It is not known if world has any...
Hello All
There is much discussion on the existence of Dark Matter.
Should we think of Dark Matter as having macro structure, ie comprising elementary particles, leading to atoms and a Dark Periodic Table?
best regards ... Stef
Hey peeps,
Ok, so I need some help here. I've just been watching some videos explaining the existence of dark energy and dark matter - something which has always fascinated me.
These videos pose the theory that for the first 9 billion years of the universe dark matter ruled but, for the last...
This is probably a long shot but it's worth trying. My question is the following:
What properties of dark matter can we derive from each of the available methods for probing the physics of dark matter?
To elaborate a bit, my understanding is that the evidence for dark matter comes from its...
I am a First Year Undergraduate Physics student. Which will be the best textbook for me to study properties of matter (Elasticity) and fluid mechanics? I prefer a better theoretical understanding.
Ok, so where do I begin? So I'll try to make this as short as possible sparing you all my issues.
I like thinking about what is. My math takes me as far as pre-calc, but have no training in this field. I have the utmost curiosity in understanding the functioning of everything. Specifically...
If we take a spherical distribution of matter wherein gravitational force and cosmological-constant force are equal upon an object on its surface, then does the time that it took for that volume to grow to the size wherein the two forces are equal match the time it took for the universe to start...
As we know that matter is Anything which has mass and occupies space then are the Subatomic particles like electron,proton and neutron a matter.
Is electron a matter ?
Is proton a matter ?
Is neutron a matter ?
As these particles have mass and they occupy space so they are matter,
But the...
I am currently an undergraduate sophomore at a US university that is very reputable for physics. I am majoring in physics, and would like to one day attend grad school, so I tried to start research early and was able to find a research position this fall semester. I emailed a couple of theory...
I was going over the Einstein-Hilbert action derivation of the Einstein field equations and came across a term that does not seem to be explicitly defined. That term is the Langragian for the matter fields. What exactly is matter in General relativity in the context of the Lagrangian? Here is...
This is going to be controversial and might even be taken down, but I think what I will say is absolutely true, and I'm sorry if it offends people.
I'm applying for the second time to condensed matter PhDs. I was in a group that did a lot of device fabrication as part of their experiments and...
I understand that the mass is being converted to energy but isn't it just an destructive interference of the properties of particles being present as waves of possibility , for example when electron is Interference with it self is it produce energy?,
because the particle are weaves in quantum...
Given a system with some heat capacity. It is at any temperature T, and it is covered by two layers A and B. Say layer A is poor conductor of heat and B is comparatively better.
If we let the system sit in a matrix of lower temperature for some time (long enough for heat to pass through A but...
Greetings All,
Well, this is the question from my 9 y.o. son: what will happen if a famous Everest heavy spoon of neutron star matter is actually removed from the star? I am inclining to his version that it will explode rather quickly, e.g. neutrons will quickly decay into protons-electrons...
The speed of star on the outer of are solar system is not according to the visible mass.
Change the law of gravitation F = 1/r^2 to fix this.
Galaxies far away are moving away with increasing speed.
Change the law of gravitation F = 1/r^2 to fix this, include a repulsive force to fix.
Would this...
I understand that the Big Bang was an explosion from an extremely tiny mass with particles and quanta traveling away into empty space (anything out there at the instant of this bang being too far to hit yet). I also understand that some ejecta from the Big Bang have been colliding since then...
https://phys.org/news/2018-04-dark-interactive.html
"Observations using the Hubble Space Telescope appeared to show that a galaxy in the Abell 3827 cluster - approximately 1.3 billion light years from Earth - had become separated from the dark matter surrounding it.
Such an offset is predicted...