Matter Definition and 1000 Threads

the moment there was matter there was time and thus even as time was shaping up to be the dimension we now know there must have been another dimension let's call it :"time2" in which our time was forming، can you say that? This is because time is matter as it forms the fabric of space and time.

Ordinary Standard Model neutrinos _are_ dark matter particles, in a sense that they have mass, and they only weakly interact with everything else. IIRC they are not considered to be a satisfactory candidate because nearly all neutrinos in the Universe are relativistic, whereas we know that...

there is considerable research interest in supersymmetry, both for string theory and particle physics.What would be the implications to physics if parity symmetry is a fundamental symmetry, and therefore mirror matter and mirror bosons exist? would this imply mirror matter has all same exact...

ok so this has been on my mind for a while. If the hotter a stars burn or flame the further it goes on the spectrum correct so what if it burned so hot it is literally invisible wouldent that be considered a dark matter then it's a dark matter sun

What will the scientific experiment look like that finds Dark Matter? Before then, what scientific/technological advancements will need to be made in order to find Dark Matter?

The universe is believed to be 13.8 billion years old and at least 45 billion light-years in radius. Now there is also a black hole at the center of our galaxy, with my basic understanding of black holes I understand that this would warp time and space, is it possible that it's warped so much...

I heard a matter field.Like every fermions and bosons have their field.How this works.I don't know QFT so..I am not even sure this is the right area to ask this questions But here it comes,Whats the matter field ? in simple way is there anyone that can explain it to me ?

I am in college and trying to develop a theorem, If there is any information there is any papers or evidence to dark matter being particles could you please tell me as it will do me a great favor. Thank you for reading

I am an A2 physics student and I have chosen to do an Extended Project Qualification (EPQ) on 'What Is Dark Matter and To What Extent Is It Worth Researching?' I need to have a primary source of research for this and a forum thread seemed as good as any due to the opnion based nature of the...

I am unable to find a paper on this only the abstract, but it seems to be saying that there is no Dark Matter? The tightness of this relation is difficult to understand in terms of dark matter as it's currently understood, the researchers said. It also challenges the current understanding of...

Observations have led to the conclusion that the Universe contains dark matter, a form of matter that has mass and therefore gravity, but apparently doesn't interact otherwise with 'normal' matter. It's existence is unexplained. Then there is the puzzle of antimatter, a form of baryonic normal...

The electromagnetic wave derivation uses the fact that charge enclosed is zero and it goes to obey plane wave equations. Lets say we were deriving a wave equation from maxwell's equations for electron wave motion, but we assume that charge enclosed is not zero, and come up with some...

It has occurred to me since May 2015 that for certain purposes the matter term in the Friedman equation might benefit from a modification. https://www.physicsforums.com/threads/how-does-a-particles-kinetic-energy-vary-with-a-t.811627 The Friedmann equation shows the matter term to be based on...

Hi, I ask you to recommend a good book (not too hard) for studying the physics of matter (Atoms, molecules, statistical physics and solids). Actually, I'm studyng on "Manini - Introduction to the Physics of matter", but it's a very bad book... Thanks at all!

For graduate school admissions? I will finish my third year this April and then will start an 8 month full time research project. I will have the possibility to graduate with 7 semesters instead of 8, but if I apply to graduate schools next December I will not have any first term grades. Would...

This article of Dubois-Violette http://www.sciencedirect.com/science/article/pii/S0550321316300566 https://arxiv.org/abs/1604.01247 suggests that the diagonal in the exceptional jordan algebra H3(O) should be interpreted as chiral dark matter. Is it the same in other octonion-based models, or...

I am 18, I am going to be studying German in Germany for 10 months, and then go to a preparatory year (German studienkolleg) I will probably be 20 or 21 before I start actually studying in the university ( although I finished high school at 17 and got accepted in my home country's university...

I wonder if someone can tell me if I have interpreted the cited article correctly. https://arxiv.org/abs/1306.5534 The article seems to have calculated upper bounds on the density of DM for different parts of our solar system. We have found that ρdm is less than 1.1⋅10−20 g cm−3 at the orbital...

What is exactly the dark matter? There are lot's of things hitting at a particle nature of dark matter I mean observation of the bullet cluster, freeze out times in the earlier universe, the third peak in the CMB power spectrum. I think there is no known consistent explanation by modified...

According to this paper https://arxiv.org/pdf/1701.03128.pdf is this a fudge factor or can we have a mixture of energies for DM. Abstract. Various particle physics models suggest that, besides the (nearly) cold dark matter that accounts for current observations, additional but sub-dominant dark...

there is a lot of discussion about dark matter. Can black holes be used to explain this missing mass of the universe??

All the ordinary matter we can find accounts for only about 4 percent of the universe. We know this by calculating how much mass would be needed to hold galaxies together and cause them to move about the way they do when they gather in large clusters. Another way to weigh the unseen matter is to...

Baryon acoustic oscillations acoustic peaks in cosmic microwave background anisotropies provides evidence for cold dark matter but is there any sort of prediction as to the specific properties of this dark matter? predictions as to the mass of this dark matter, total mass, and mass of the...

In my quote above from the thread https://www.physicsforums.com/threads/ultimate-fate-of-the-universe.898640/ I omitted consideration of dark matter because so very little is known about it. I am hoping someone here at the PF might be able to discuss the following questions. QUESTIONS Assume...

I know that a black hole it's a singularity, but its event horizon gets bigger the more mass/energy you throw in. I thought that like dark matter interacts gravitationally with regular matter , it would interact with black holes, eventually falling , increasing the mass of the black hole and...

Ok - I have qualified this question with the word stupid so please go gently with me. Imagine you are talking to a rather stupid child when answering please. My question is about dark matter. Every time I do a search for "proof of dark matter", I get the same answer, which is that using the...

is it possible the dark matter in bullet clusters & CMB accoustic peaks were the result of black holes, originally from baryonic matter, but galaxy rotation curves are MOND. So MOND + dark matter as black holes from baryon, not dark matter particles

Thanks to all of you for your kind attention to my questions. May I ask another? If what we're calling dark matter interacts with visible matter via gravity, wouldn't it be concentrated along these arms if density waves are a feature of gravitational force?

I keep reading articles that assert that spiral galaxies would fly apart if it were not for the presence of a dark matter halo. The observation that rotational speeds vary little with distance from the center is usually cited as the 'proof' of dark matter since this behavior would otherwise...

Do we need more proof of dark matter than this?: https://en.wikipedia.org/wiki/Weak_gravitational_lensing

Unexpected interaction between dark matter and ordinary matter in mini-spiral galaxies "We studied 36 galaxies, which was a sufficient number for statistical study. By doing this, we found a link between the structure of ordinary, or luminous matter like stars, dust and gas, with dark matter."...

If the universe is indeed flat and the cosmological principle holds true, does this mean that there is an infinite amount of space in the universe as well as an infinite amount of matter?

Homework Statement Why can't i use the equation to determine the normal stress and shear stress ? Is my concept wrong ? I use the method in the link to do this question. The question said the stress on a plane making angle 30 degree anticlockwise from plane AD . Homework EquationsThe Attempt...

Hello, my name is Pedraam and I am newly getting into Astrophysics and stuff. It is very interesting to me so far! My question has to do with dark matter. I'm curious as to why we look at Newton and Einstein as such gods that if they're theory is slightly off, even in the cosmic world, we have...

A matter-antimatter pair have opposite spins and charges. Is this the same for parity?

Homework Statement Hi, I am trying to solve for the cross section for a gamma ray energy. The element I am using is Europium and the energy peak is 244.7 keV. From the slope of the graph I was able to determine the mass attenuation coefficient to be 8*10^-5 m^2/kg Homework Equations σ=(μ*A) /...

https://www.inverse.com/article/24863-dark-matter-might-be-smoother-than-we-thought Scientists have yet to actually observe dark matter in the flesh, but most research up to now posits it’s the kind of stuff that clumps up and aggregates into unwieldy masses around the universe. New research...

Can anyone suggest some books which deals with electron correlations in many body systems?The book should cover second quantization,hubbard model,mott transition etc.I'm a beginner in this filed and want to learn from the very basics.

In 2005, A. Vikhlinin et al. made a hydrostatic equilibrium study - https://arxiv.org/abs/astro-ph/0507092 - of some dozen galaxy clusters. These hydrostatic studies are useful because they don't contain the M/L assumptions of other methods. From this document, I'm trying to extract the dark...

This paper favors a mixture, but there are many papers that predict Cold dark matter, is there a particle that can be ruled out, or pushed to the back of favored particles. arXiv:1611.09362 [pdf, other] Hints against the cold and collisionless nature of dark matter from the galaxy velocity...

It seems to me a possible explanation of the dark matter effect could be as follows: Thorne and Misner (p. 719 in Gravitation) note that the Hubble expansion is anisotropic. Empty space expands but the gravitationally bound space within galaxies doesn't expand. This should obviously produce...

I have read that infinite time dilation goes hand in hand with infinite length contraction for photons. AKA "photons do not experience time", or from a photons perspective, it takes no time to arrive at its destination. What if you were floating in space with a laser pointer, and you pointed...

Hello, I don't mean that question to sound rude or judging, but financially I can't really leave my state (Oregon) until graduate school. I was always told that in science where you go matters, but no one in my family except my uncle have gone to college. Thanks in advance for the advise.

Homework Statement Homework EquationsThe Attempt at a Solution [/B] So here's my question again, why do you need to include 40L of water in the total volume? It's not like AgCl is going to dissolve in water right? AgCl has low solubility in water. I mean if it was like NaCl then you should...

How does dark matter suppress baryonic osculations?

Hi all. New to PFs. I deal in (exotic) human biology, which happens to have put me at the intersection of fields and, in this instance, conceptually more challenging physics. I'm presently involved in a comparative analysis of biological versus physical time contraction-dilation. I happen to...

The double slit experiment shows, that particle only become solid when observed, shouldn't be matter behind walls aka where it is not watched be only a potential wave and not be solid at all? Is that what Max Planck meant when he said: “All matter originates and exists only by virtue of a...

I need someone to clarify where I have erred: At the start of the universe, there should have been equal amounts of matter and Antimatter created, but we appear to live in a matter dominated universe. If matter and antimatter mutually annihilate into energy, and energy and matter are...

Homework Statement Currently, the density of matter ##\rho_0^M## and of radiation ##\rho_0^R## have values of approximately ##10^{-29}## g/cm^3 and ##10^{-33}## g/cm^3 respectively. Estimate the ratio of the cosmic scale factors ##a_{eq}## (scale factor at equality) and ##a_0## (scale factor...

https://www.sciencedaily.com/releases/2014/09/140908204603.htm According to this article dark matter is warm, and provides a mechanism for showing the lack of satellite around the milky way. Date: September 8, 2014 Source: Royal Astronomical Society (RAS) Summary: Scientists believe they have...