Modern and Theoretical Physics

so i was pondering this idea but their are a few things i don't get in regards to uniform spheres and their gravity. First i imagined the universe [empty space where matter can exist] as a rotating sphere the expansion of the matter and energy of the universe was caused by the centrifugal motion of the sphere. this matter would initially be none uniform but eventually be divided equally among the surface of the sphere creating the a uniform sphere with a gravitational force of zero inside the sphere and equal gravity as the initial state [all matter condensed to a single point] outside the sphere. would the centrifugal force increase the acceleration of the matter the fa…

hopefully when i'm older and more experienced I'll know more about the existing theories in physics in depth, but until then, I'm interested to see which theory you all think is the hardest to learn (for any reason, hard maths, hard concepts, etc). From what i've heard it's probably string theory, but GR and QFT look pretty intense too, lots of unfamiliar maths required to understand them.

I was recently sitting and thinking of atoms and physics. Something interesting popped to mind... which is likely explained and confirmed / infirmed, although I never saw the idea discussed anywhere. Atoms are held together by the electrons around each nucleus, their spin influencing the strength of atomic bonds and the solidity of the material. The faster those electrons spin, the weaker the interaction. This is why most materials start to melt when it gets too hot, becoming liquid then gas. Oppositely, cold means that the bonds between atoms are stronger, so most materials get harder when temperatures are low. But if my understanding of physics are right, materi…

I have 4 main ways to keep the consciousness in our brain alive and going. 1. is my way in my first thread that would only take months and would put us in a heaven situation fast. 2 3 4 are talked about by people. 2. nanobots to keep adding new brain cells and other cells. Or turn the brain cells and other cells into fixedup immortal cells. Or create immortal brain cells, cells and add them. 3. ?????? Us fix the brain cell and cells - dna/genes/ect. to be immortal cells and somehow add/inject them? Is this even a way or....or no?... 4. Create a computer with many firing signal shooters ect. to transfer consciousness to, or, or also partially a brain made of stem cells…

Hello! I am in no way, shape, or form a scientist. I would consider myself smart, but I wouldn't consider myself educated. I have always wondered about reverse engineering and how one goes about it. You see, I've always looked at heating pads and electric blankets, and wondered, "we can use electricity to create heat, why can we not use heat to create electricity in a wrap or pad type format"? My main reasoning has always been because of cars. Why we can't create a type of film that can be applied to the outside of the car with thermo-electric receptors in them to create electricity from the heat absorbed. I would appreciate it if someone can fill me in on why it can't be…

Imagine an astronaut in a space ship which, once it has left the earth's gravitational field, begins to accelerate continuously at 9.8 m/s2. I am imagining the ship's engine is efficient enough to accomplish this. By my calculation, he would be traveling at the speed of light, relative to his point of origin (earth), after 347.125 days. Assuming our space ship has a sufficiently sustaining life support system, our astronaut should be quiet happy and healthy, having spent all of that time in a simulated gravitational field. Ironically, he would have the sensation of being a body at rest the entire time. What law of physics makes this imaginary scenario impossible?

In everyday life, chances are you only see fire where there's air. Still, there's a slightly surrealistic concept that intrigued me: Fire in a liquid. The liquid plays the role of the oxidant, and anything submerged can be the fuel. The liquid is of course consumed and transformed, but doesn't combust itself. Is this ever possible with any combination of chemicals? As far as I know, there's no material that can burn under water as we know it... typical fire reqiures oxygen. On the other side, fluids that do combust get ignited themselves... so starting a fire in a gas tank causes the whole tank to blow up. But is there ever a middle way? Is there any fluid inside whic…

I read somewhere that, fission converts 0.1% of mass to energy fusion converts 1% of mass to energy anti-matter converts 100% mass to energy is this correct and how so? *please provide links if possible*

Now there are still things I don't know about in relativity but I thought of this the other day (by that i mean many, many months ago) and I thought it might be post worthy xD this will sound a little unusual but bear with me So say you have a spacecraft with a group of incompetent, suicidal aliens inside, trying to develop a nuclear weapon to kill themselves with. They're doing this by trying to squeeze a piece of nuclear 'fuel' so that it reaches a particular density where, if you fire a neutron into the fuel, you could get a successful nuclear fission reaction going, triggering the nuclear fuel and causing it to destroy the spacecraft and them inside it. …

So the LHC has verified the existence of a new type of hadron consisting of two quarks and two anti-quarks whereas QCD previously predicted that the only possible arrangements were either a three quarks ( or anti-quarks ) grouping , or a quark/anti-quark grouping. What does this mean for QCD ? Does it need to be scrapped ? Does it need modifying ? Is this of no significance, just an embarassement for Murray Gell-Mann ?

I don't even know if that termed correctly.. Can a plain piece of " typing" paper " " white paper" held up to a light source reflect visible light frequencies and can these "colors be visually seen by an observer? Ive read: White surfaces are composed of molecules or atoms that don’t absorb any of the visible colors of light. --->"But" those are surfaces not paper, is this correct to compare???

Hi, I am 18 and although I know a lot about physics and stuff I am probably missing lots of knowledge and probably even simple things in physics. My idea from what I know follows physics and I think it could work maybe, I first realized it when I was 14 and still I have no proof it can't be made/work, and am obviously then wishing for it to be studied and built by the people that could test and make it. So here is my whole plan below, with I know some extreme possibilities if the beginning works, and then those extremer things might work. So here it is below... (it's a saved paste of everything) So could we under a Ultra-High-Vacuum Atomic-Force-Microscope (UHV AFM) o…

I'm not a physicists, and I never will be, so I'm not sure if my theory goes in this part of the forum, and if it doesn't just move it to wherever in the physics forum it's appropriate. One of my hobbies is writing, so in my AU which is not quite a fantasy story there are people that evolved from birds. I didn't want to have the same mass as birds or have four chamber hearts so I decided that the best attribute for them to have is a plasma bladder, which is kind of like a swim bladder in fish which can contain air, but it can instead contain plasma which the creature would absorb from the environment and produce inside of them. I want to know if this back story is phy…

always wanted to know, but never had the time/ knowledge to educate myself.

This demonstration of inductive heating is awesome... Kinda makes you want to run out and buy some copper pipe right now... Seriously, is this real or some sort of trick?

Hi . If we use meny gap in Casimirov effect and width is 1e-9 m and width between gaps is 1e-6m ,bude casimir effect work? BTW. between gas is dielectric material. Thank. By.

I did a bit of crude reading on the matter and it appears that this is plausible although there is no way to prove it at the moment: Certain types of black holes also exhibit the "time travel" abilities of Tipler cylinders. Kerr was one of the first to describe the dual event horizons of a rotating black hole. As with Tipler's cylinders, it was possible to travel on a "time-like" trip through a Kerr black hole and end up in a different worldline without being squished by the gravity of the singularity. The mass and gravitational field of a microsingularity can then be manipulated by "injecting" electrons onto its surface. By rotating two electric microsigularities a…

Hello there! I love physics, and I am 16; I don't have the full background of theoretical and quantum physics. So every time I read about a theory, I go and ask my physics teacher and he tries to explain it simple enough for me to understand it since we (as a class) didn't yet start with modern physics. So he told me if I want to understand such theories I must read about the exchange between matter and energy. So can anyone help me to find a PDF about it? Thanks!

If I could accelerate a probe to "c" and send it directly at the center of the spinning axis "perpendicular to the accretion disk" entering at either pole at a black hole, would it pass the event horizon without being stretched and could it pass directly through to wherever, or would it be accelerated to the speed of light squared, essentially making it more than likely cease to exist because at that moment, "time" for the probe would possibly slow down and stop.

Hi I was just wondering if it was possible to make atoms of an element or multiple elements to be attracted and gather together in one place in an open environment? Like would one be able to make Helium atoms gather in a center of a room due to an artificial attraction to the area you want them to be positioned in?

Hello, I don't believe that materializations of spirits is really existent, but I have seen in the internet something about materializations: http://en.wikipedia.org/wiki/Albert_von_Schrenck-Notzing If you look at the picture of Eva C. you will think that the picture is faked... But now a question on physics: From quantum field theory/ and particle physics it is well-known that particles can be created from vacuum for a short time. But a human being consist of billions of particles. So if someone starts to compute Feynman diagrams with billions of elementary particles and (using standard model of particle physics) it will be an enormous expenditure; but the proba…

I've heard that warp drives need negative energy in order to contract space-time in the front of a spacecraft. But, space-time expands when you have charge, doesn't it? In the Ressner-Nordstrom solution, the metric is given by [latex]ds^2=-\left(1-\frac{2GM}{rc^2}+\frac{Q^2G}{4\pi \epsilon _0 r^2 c^4}\right)dt^2+\left(1-\frac{2GM}{rc^2}+\frac{Q^2G}{4\pi \epsilon _0 r^2 c^4}\right)^{-1} dr^2 +r^2(d\theta ^2 + r^2sin^2\theta d\phi ^2)[/latex] Which means space-time is contracted by charge. Why is it that warp drives are not able to use charge instead of negative energy?

Hi, in classical physics, in a closed system energy is conserved for every instant of time. But in quantum physics, quantum fluctuations (very short particle/energy creation or annihilation) on microscopic level can occur. But both theories have the same propertiy that the Noether theorem holds: If the theory is invariant under time translations the energy is conserved. In every quantum field theory there is time translation invariance. But are there theories that are time dependent (i.e. theories that break homogenity in time)? Why, the homogenity in time and homogenity in space are the most essential symmetries in physics (of course there are theories that viol…

Ideal gas law is simple and very useful for calculation of high temperature thin gas phase. To calculate real gas, one of simple simulation methods is molecular dynamics(MD) simulation. How to simulate very simple real gas phase? Can we do simple simulation at the PC?

Hello, I am looking for recommendations on introductory literature about crystallography. I am specifically seeking out materials that are quite visually oriented with as little advanced math as possible. My intention is to gain an aesthetic appreciation, and some conceptual level of understanding things like space group transformations and self-organizing inorganic matter. Is there a "Brief History of Time" for crystallography? I am coming from a musician/artist background, hence the request for something very visual and aesthetically compelling.