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).
Today 16:00 UTC, in ~7.5 hours.
Announcement, Link to Zoom meeting (why is this just an image on the website, not a link?)
LUX-ZEPLIN (LZ) uses several tonnes of xenon to search for signals of dark matter interacting with it. It started taking data last year and it should easily set better...
Do they really teach and help anything? I am taking them for my nanoengineering undergraduate program. The textbooks are solid state physics by j r hook and concepts of modern physics by mcgraw hill and r b singh introduction to modern physics and introduction to quantum mechanics by david j...
Apparently I always find myself back here when bad things happen lol..like damn it’s been six years.
Recent college graduate. I want to take a year or two working and honing my skills before graduate school. One, because I’m tired and need the break but also, two, for reasons beyond my control...
If we imagine launching an electron wave in a reference frame S with speed v, should someone viewing the electron from frame S1, which is in inertial motion referring to S, use the relativistic velocity addition to calculate the speed of the electron?
While this was inspired by another thread, I think the question is different enough that it can be asked separately. It's also more suited to this forum than the forum where the question that inspired this one was asked.
Wiki gives four possible interactions for interactions of gamma rays with...
in the grand scheme of things, our life is an imperceptible blip on the universe's timeline. we are insignificant, and we don't really matter. no matter how successful we are in life, or how our lives end, all our accomplishments will be erased during the heat death of the universe, along with...
The relationships for matter waves are (see e.g. https://en.wikipedia.org/wiki/Matter_wave):
λ = h / p and E = h f, where E = m c2
From this the phase velocity can be derived and we get vph = c2 / v.
v is the group velocity, which is also the velocity of the particle.
If I consider these...
Hello,
I have recently come across this article by Rizzi and Ruggiero, called "The Relativistic Sagnac Effect: Two Derivations": https://arxiv.org/pdf/gr-qc/0305084.pdf
In section 3, the authors derive the Sagnac proper time difference for all beams (light beams and matter beams, including...
I have been working on a relatively simple problem. Just take a quantum wave function for which a physical requirement is that an arbitrary displacement of x or an arbitrary shift of t should not alter the character of the wave, and I want to find the state function solution. A possible guess...
The possible forms of solids can be more than just amorphous solids and crystalline solids. I tried a look at a couple of wikipedia articles and one of them showed descriptions of Plasticity, elastic, and Viscoelasticity, but those are not enough. I can only think to give some real world...
what about Modified Newtonian Dynamics + dark matter both right and both correct
Are sterile neutrinos consistent with clusters, the CMB and MOND?
Garry W. Angus
arXiv:0805.4014 [
If no sterile neutrinos then Modified Newtonian Dynamics + primordial black holes
Primordial Black Holes...
Some physicists prefer to explain the problem of conservation of energy in General Relativity by considering the gravitational potential energy of the universe that would cancel all the other energies and therefore the energy in the universe would be conserved this way.
However, many other...
Summary:We propose a search for low mass dark matter particles through momentum recoils caused by their scattering from trapped, nanometer-scale objects.
The Paper linked details a novel concept for detecting WIMPs. I hope to see more work performed on the idea in the future...
Does dark matter(DM) fall into black holes(BHs)?
IMHO it should... ...as it does interact with normal matter gravitationally.
Once it's done so, does it add to the BH's mass?
Again, IMHO it should. AFAIK it does have mass...
Would that "quasi-convert" it to normal matter?
...after all, this...
Unsurprisingly the Milky Way seems to have been studied a lot. We have really good luminous mass profiles (e.g. McMillan 2011) and increasingly accurate circular velocity observations for stars at various radiuses (e.g. Eilers 2019) meaning we can confidently infer dark matter models.
So the...
Big Bang singularity can never be solved, so
Could the "big bang" have been an event where a large sum of highly-dense dark energy converted into mass, and in doing the result is like a nuclear explosion?
Could the "big bang" just have been a large sum of matter where the core becomes super...
I was reading a Chemistry book when I read about the three states of matter. Everyone knows what they are, but I didn't know the simplest way to describe each of the three until I read this book. It said that a solid has a shape and a volume, a liquid has no shape but has a volume, and a gas has...
This thought surprisingly came from thinking about the definition of temperature and the symmetry breaking that separated time from temperature. Which led to thoughts about symmetry breaking that separated QM from GR. Which led to to the symmetry breaking that separated dark energy from baryonic...
Hi. This semester I have chosen "Properties of Matter" as my Physics Elective. The university syllabus generically prescribes texts by Newman & Searle to be studied in this regard but tbh I find them somewhat outdated.
Below I have attached a small snippet of my course syllabus. I shall be...
Originally Answered: If light reaches the Earth from the sun, why is the space between the sun and the Earth dark?
Because light illuminates surfaces, objects. Space is not an object, is the lack of matter. If you turn on a flashlight in a dark room you will illuminate the floors and the walls...
The EM field seems to be required for for local gauge symmetry of the electron matter field under local phase variation. Following is a description (not my verbiage):
There is a symmetry in physics which we might call the Local Phase Symmetry in quantum mechanics. In this symmetry we change...
I have read that almost 80 to 90% of our space is made of dark matter or Dark Energy. But what is the function of this Dark matter or energy? Is this something that binds stars, galaxies, etc? If not then what is the actual matter with Dark energy?
Hi everyone, I was in physics class and the professor asked if the inertia of matter changes in a black hole and I would like to know if anyone has the answer to this question.
Summary:: Difference between the material and matter
They look similar but I know they differ. What might be the possible difference between them? Let's discuss.
Hi all, I just graduated from my master's program in theoretical physics. I did 60% of the coursework in high energy physics and rest in condensed matter theory plus a few experimental physics courses. I did my master's thesis in what can be called as theoretical cosmology, studying particle...
I've been reading up a little on IC1101, the largest known galaxy and there is not a lot of info on it, but it seems to have an unusually large mass to light ratio according to this popular article (see half way down):
According to this article at 20kpc it's got 12:1 mass to light, at 200kpc...
Will there be a compression of matter that the planet is made out of due to gravity when we are talking about planets? If so I would like to know what the effect would be in the example given in the summary.
I am on my first year of my master's degree in nuclear and particle physics, and right now i am ending my first semester, where i decided to take a course in physics of semiconductors. As i end this semester i start to wonder if there was any use in learning about this subject, as it seems like...
Are there any limitations on producing a significant number of electron-positron pairs (say, 10E24 electrons) in one second using the Breit-Wheeler Process or Nonlinear Breit-Wheeler Process? What variables affect this outcome? I suspect it mostly comes down to the pulse repetition rate and...
Energy and mass are interdependent and electrons can manifest as particles and fields as do all other particles, but is it generally true that physical(classical) matter is a peculiar type of energy that can(for some reason? What?) manifest as physical objects?
if we assume each photon of light as a very very light piece of matter (by famous E = mc^2 and then: m = E / c^2) and sum up all photons that have been made from the creation time of a galaxy (also considering limitation of speed of light) and also photons that accidentally passing throw that...
Hi all,
(I also posted this in the high energy theory section since my impression is there is a deep interplay between modern condensed matter theory and high energy theory).
Some background: I'm interested in the interplay between condensed matter and high energy theory. I'm a bit more than...
What would be the distribution galactically, universally etc? How might distribution of DM change if involved forces, masses, energies or other fundamental components of DM occurred at different weights ie: Could there be less but stronger or perhaps "more but weaker" models of DM?
What would...
I would like to ask scientists or anybody: what do you think about qwarks, do you consider them to be the littiest parts of matter or that matter is cyclically or infinitaly smalling, like numbers, or that there are some smaller parts, which have not been observed, but they have an end in their...
Summary:: What does physics study?
Other than matter/antimatter and energy what does physics study? And in what ways are matter and energy similar? Are there additional substances that physics measures?
Hello, could you please recommend some good introductory textbooks for studying core topics in astrophysics/cosmology, and especially dark matter?
I know that 'An Introduction to Modern Astrophysics' by Caroll and Ostlie is a good book, but I 'm looking for something more concise, so to speak...
I'm new to relativistic quantum mechanics and quantum field theory and was trying to learn about the Dirac equation.
Unfortunately, I got a little stumped by the interaction between matter and antimatter.
It seems like the time derivative of matter is dependent on the spatial derivative of...
Given that we know experimentally that time slows and space bends in the presence of matter, what is the actual physical mechanism that enables matter to bend space and slow time?
Scientists finally created a 2D Supersolid! There existence has been predicted since the 60’s and now we have them. The scientists who created it don’t really know what it could be used for as it’s so much in the infancy stages, it’s practically a zygote. As an aspiring futurist, I was wondering...
My understanding, possibly my ignorance, is that dark matter is calculated to exist from observations that there's not enough matter to fit observations if the current theory of gravity is right.
Is it possible to put into a nutshell why the case for dark matter together with current...
Could dark matter consist of black holes formed shortly after the big bang? They would form the perfect development seed. If they all have Sun-like masses then they are not detectable from here (they are just 3 kilometers wide!). They have virtually no collisions with stars and could form a...
Imagine a bolted joint with a washer between the bolt and the surface.
Assuming the washer is always covered by the bolt head so it's getting a consistent load, does the washer's diameter impact the static friction being imparted on the surface?
I see two conflicting ways of viewing this...
Question: How accurately does the observation of the current dark matter to baryonic matter ratio fit with its influence on the BBN?
Some good references would be very helpful.
Here are some references that I think might be a little helpful.
(Mar 6, 2004)...
I am trying to understand how is topology used to characterize materials. So I understand that to calculate the Berry phase you will parameterize your Hamiltonian and change this parameter in some way and return to the initial value. What I do not understand is what does this changing of...
In a paper written by Jonathan Schaffer entitled Spacetime the one substance (https://philpapers.org/rec/SCHSTO-7) which I have not read but which I found as a reference in a book by philosopher Philip Goff, Goff suggests that matter is actually created by a curvature in spacetime rather than...