Modern and Theoretical Physics

Are the universal fndamental constants realy constant? There has been speculation that the speed of light is slowing down, I read up on this and accurate measurement taken of LS over years has apparently shown a slowing, thereof? Was this just due to ever and ever more accurate methods of measuring or do you think this idea has any merit.? If this idea is really right why should the other constants be constant? Creationists use this idea with glee trying to tell us during the early universe Light Speed, was much much faster, which explains, somehow that god made the whole universe in just six literal twenty-four hours days. In my opinion, the constants…

the reason I ask is because I just watched a film called the black hole that is based on the story of exploring the inner workings of a black hole so naturally it got me thinking and what I thought was why does a black hole suck everything into its self besides the whole gravity thing I mean it only seems logical to me that once something is dead it loses any ability to produce any kind of force think of it like a human that drives a bus for disabled people has a route each week to pick up his clients and take them out for the day if he died those same disabled people would stop receiving there weekly trips at least until the driver was replace so why does the gravity not…

Hi! I am working in a range finder project. I have encountered a problem with an Avalanche Photodiode. I am trying to use a pulsed laser on 980 nm(infrared) but I receive a lot of noise from the APD. I want to ask you if in the APD must be totally dark and no other light must enter in the APD box? Do I need to use a infrared optic filter? What kind of optical filter do I need to use? I use a lens with 10 cm diameter . Thank you, I am not physicist, I am a programmer and an electronist

Hi, I am wondering if it's possible to prove you are on a actual moving plane that is actually moving from one city to another. I was wondering what myth busting technique would be needed to be used to truly know for a fact that the plan wasn't just an illusion and that you can be 100% certain you went from A to B. My ideas so far: Remember the land you were at, then look at the land you are at after and see if it has any similarities. Keep watching outside the window and make sure that nothing sketchy happens... where it looks like you are watching a big screen video. Test the plane with a pendulum Can I hear your ways to know definitively that a plan ride is …

Positively-charged nucleons resist fusion, according to the EM force. Logically, to compress plasma, with EM force-fields, seems impossible -- the charged particles repel each other, at nanoscopic range; but they would be compressed, with EM force-field-generating equipment, at macroscopic distances away. Since EM force-fields decay with distance, a fusion reactor would have to generate enormous fields, macroscopically, to over-come the particles' repulsion, at "point-blank" nanoscopic ranges. Gravity in stars can over-come EM, b/c gravity is cumulative -- w/ enough mass, even the Strong Nuclear Force can be over-come, in relativistically compact objects. But, f…

PHOLEDs (short for PHOsphorescent Light Emitting Diodes) are light sources that are almost 100% efficient. Would it be possible to create solar cells that use a similar principle, but in reverse, so that they too would be almost 100% efficient?

How much of the stuff Eric Dollard says is true? I checked Wikipedia. The people he talks about did exist. Did Steinmetz discover free energy? Did Tesla find cosmic rays 30 times the speed of light? Did Alexanderson send signals instantaneously? Did Philo Farnsworth invent fusion? Did Heaviside solve the transatlantic cable problem "mysteriously".

Hi, I'm working on Lanczos method but I don't know how can I calculate ground state wave function with Lanczos method. Is there anyone to help me?

Hi, I'm new in MD simulation. I have a question: how to determine the force constant in a polymer chain?. Example I have a bond, angle harmonic and dihedral multiharmonic with parameters corresponds. How can I calibrate thess parameters. Could you suggest me some articles or books for reference. Thank you.

If gravity is a force that interacts with matter via space, and gravitational waves are the measurable transfers of this force, then are all gravitational interactions due to gravitational waves, but most masses give off minute and constant gravitational waves which can't be detected very easily? Is that what the inverse-square law of gravitational is then, describing the dissipation of any gravitational wave over a distance?

Please let me know if the sizes of electron and photon are point like or extended in nature and what evidences are there for the agreed upon size .Is there any way to compare the sizes?

What is the difference between acceleration and jerk? Jerk and the fourth derivative? What happens as n approaches infinity? How does the energy of something change as it experiences jerk or 4th derivative motion in a certain direction? It seems like higher derivatives of motion could describe vibration or other frequencies.

Titanium shell covered with Kevlar and then thermal ceramics on top. It would be powered by magnetic cone plasma thrusters. Using oxygen and small amounts of hydrogen. Using high powered laser pulses to ignite the fuel. There would be two cylindrical electro magnets creating an encompassing magnetic field reducing the relative mass to nil. It would have particle filter wings to collect hydrogen, oxygen and nitrogen from planetary bodies having sufficient atmosphere and low enough gravitational pull to allow reentry into space without landing or being pulled to the surface. The vehicle would use batteries to start. Then a water pump to pump water through tubes and a turbin…

Lately I've been having some discussions with people online (theists), and one of the things that I find is almost invariably brought up on at least one occasion is that the Big Bang is supposedly, according to science, the absolute beginning of everything, and that this has been proven by something known as the Borde-Vilenkin-Guth Theorem. Now, I know that the latter comment is simply not true, as all three of those scientists have gone on record and clarified that their theorem only demonstrates that the expansion of our universe has a definite beginning, not necessarily existence itself. But as for the Big Bang itself, I was always under the impression that all sci…

I am not well versed in physics, which would probably explain why such a stupid question is being asked here, but I just can't seem to wrap my head around time being slower around certain masses, and at velocities relative to observers. If one person is close to a black hole, why is that 1 second slower than one on earth? Logically, it doesn't seem like it should move slower. I guess if you view space and time as a fabric, and gravity bends that fabric, then time is adjusted due to gravity, but why does space and time have to be a fabric, theororetically? Or if a person is traveling at the speed of light away from an observer, if they are both holding a stopwatch,…

I gather from news that there is a fair amount of scientists working warp drive technology: http://www.scienceworldreport.com/articles/7120/20130527/scientists-refine-warp-drive-concept-using-space-time-distortion.htm So my question: is there anyone here with a comprehensive enough knowledge of science history to tell whether there was some technology being worked on at some point by x amount of scientists and getting x funding, comparable what is being done in the area of warp drive. I'm asking this cause I want to get a rough estimation of whether they'll be able to build one of these things within my life time. It seems a lot of people think it's possible. So mayb…

Does anyone know whether the common fundamentalist claim of something existing 'outside of space and time' has any meaning whatsoever given what we now know about the universe? I mean, to me, saying that essentially reduces to 'existing outside of existence' since existence is necessarily spacial and temporal. It seems to me like a clear violation of the Laws of Identity and Non-contradiction, which of course is logically impossible, but I'm not a physicist so I don't know for sure.

why dont electrons jump off a wire when the wire makes a right angle turn.shouldnt the mass and speed make gforces unimaginably strong?

im a member of a research forum and we are looking for somebody who is experienced with ionization math and magnetic field math.im not trying to steal members from this forum.we just occasionally need a math guy.we would bring our questions here but the designs we work on are potential money makers so we dont wont to give away our ideas.if interested in partnering up with us please post on this thread .we could use your help and there is always the potential for money.

hi, I am 19 years old engineering student but have a huge interest in theoretical physics. Can you suggest any reference where I can do this?

What is the size of a monoxide atom relative to carbon? The recent IBM atomic animation clearly shows the two nuclei of carbon monoxide molecules. Which atom is the larger? Why? ron

Hello all! Im not sure it this question is more chemistry... bear with me My question is: If I, hypothetically, enclose a bubble of saturated salt (NaCl) water in a salt monolith, would the bubble over time rise to the top because of the density of sat. NaCl(aq) < desnity of NaCl(s)? And, if it does move or spread, assuming standard conditions, can anyone make an estimate of when the bubble would burst and/or the water touches the atmosphere? Cheers, OB

If they are both point-like particles, do we know what the physical difference is between the electron and the positron?

How are all the fields linked? at the LHC, two particles collide, why do they change the higgs field and produce a higgs particle?

I've been thinking about the common properties between waves of electromagnetic radiation and waves of macroscopic things like water... eg. we understand them in terms of wavelength and frequency. Isn't that a pretty big coincidence? Why is this so? And is this actually so? For example, have we actually unified any of the equations or is it just convenient to use the word wave? First post be gentle.