Physics

The other day I was watching HBO's "Chernobyl" which by the way is amazingly shot, beautifully directed and I can't really recommend it enough. There are quite a few factual and authenticity issues with the series, but those are all pretty minor and are well within artistic license boundaries. At the same time one part of episode 2 struck me as a gross exaggeration. In this part of episode a Belorussian nuclear physicist Ulana Khomyuk (who authors admitted in end credits was a fictional character, a combination of dozens of scientists helping recovery efforts), discovered that as a result of upcoming meltdown of the reactor, corium lava with temperatures well over 2…

What are the 10 unanswered questions in current Physics in your opinion ? even some not 10 !

I recently stumbled upon something called the "Supersymmetric Artificial Neural Network" or (SANN) on reddit/machine learning, which the author is to discuss at Gordon Research's next String Theory Conference in June. With the recent proliferation of machine learning in the realm of physics (such as Katie Bouman et al's recent black hole photo powered by machine learning), I think this thread is appropriate here. That said, from my understanding, Supersymmetry (which the SANN model above utilizes at its core) emerged in Superstring theory which unraveled a theory of both bosons and fermions in the same symmetry group. (See this review including the SANN model a…

I thought it would be interesting to find examples of really clever experimental techniques. So not not necessarily experiments that have produced important (or difficult) results. And not just examples of really advanced technology. But experiments that used clever "tricks" to eliminate errors, cancel out other effects, or just to make the effect visible in the first place. One example is Pound-Rebka: this used Doppler shift to cancel out gravitational time dilation of gamma rays from the top of a tower. They then did the experiment again with the source at the bottom of the tower. By subtracting the two results, they doubled the measured value (and probably ca…

Hello, I recently acquired this instrument, and I've not been able to figure out what it is. The label says: "Deflectometre JYC Jobin Yvon [crest] Type D2 No. 214 Paris-Arcueil" It is nothing like any other deflectometer I've found in research. See photos. Some knobs offer a very very fine adjustment of the lateral and vertical angles of unit. Others change lenses. The dark one is looking forward into hole where central eyepiece unscrewed from. There also happens to be a loose ball bearing inside instrument, about 8mm. Zero info on this to be found online! Hard to believe! Curious to hear feedback, thx in advance. Hope t…

Is there a material that behaves like a seat belt ? Locks when fast pulling and allows movement during slow pulling ?

Dear moderators: if this post violates the forum’s rules, please delete it and I apologise in advance. The objective of posting this video link is to encourage further discussion of a mathematical model. This mathematical model can represents and unites those fundamental interrelationships. Therefore, it unites social science with natural sciences, and further, science with philosophy.

A quickie... What does the term 'energetically favorable configuration' means? Does it have any strict meaning at all? One might say, for example: "magnetic domains will set into an energetically favorable configuration" (but my question is general, not about magnetic domains in ferromagnetic materials). (If it means 'lowest possible energy' then I guess that closed systems cannot have 'energetically favorable configuration' as the energy there is conserved)

Hi, I have a pipe connects to a container's outlet. The container contains water and the pipe is open-ended. When a 10Kg object is placed inside the container and compress the water. Can you tell me how to calculate the displacement of X and Y? What principle or formula should I use? Thanks,

Despite my background in physics, I've never fully wrapped my head around what weight's supposed to be, other than "not the same thing as mass." It used to hardly even matter, but now I need to know for my students. For instance, if an astronaut is in orbit around the Earth, and the centripetal force is provided by gravity at precisely the right magnitude for the astronaut to feel "weightless" in this non-inertial reference frame, said astronaut would experience "weightlessness," but force of gravity would not be zero. What would be zero is the normal force, as there is no need, until the astronaut encounters an object in spite of weightlessness, for a normal …

I understand energy is defined as the potential to do work, and is a property of a system depending on the systems configuration. I have also heard that E=mc^2 implies that energy and matter are equivalent. Would this equivalence not then imply that mass is also a property of a system dependent upon its configuration? I'm not sure what that really means.

Hello everyone, Can technically do this reaction with a good performance and a very high level of security? Because there is more news on the merger. There is a limit of mass or energy to have to stabilize the reaction of fusion it is for that the small sun does not exist. the equations of infinity small to make the fusion will all lead to inculcating more mass to their calculation to be able to cross the condition of infinitely great to have an energy of a sun to allow the fusion to stabilize itself. because our experience to have a stable fusion is made in the infinitely large so we must also respect the condition of having a solar mass energy to stabilize the…

Hi everyone! I would appreciate any knowledge you have to offer on this topic~ I am making a board game for my friends to play, and I need a way to hide symbols on spaces of the board---something completely invisible that can be revealed with some tool/anything when triggered. My optimum solution would be some type of lens that reveals the symbol when held over it, and the symbols are completely invisible to the naked eye, but don't let that stop anyone from proposing any other idea they have that could accomplish this! Also, it needs to be a long term method that would last indefinitely, and not become less effective after a few uses (basically permanent). …

Hi, I have a pipe connects to a container. The container contains water and a heavy weight compresses the water stored inside the container. The heavy weight will force the water move up through the pipe. Does the pipe connection level affect the height level of the water inside the pipe? In Fig. A, the pipe is connected to the bottom of the container; in Fig. B, the pipe is connected to a higher location. Will X2 raise higher than X1 or will they be the same? Thanks,

A piston can freely move inside a horizontal cylinder. Initially thr piston separates the cylinder in two parts of equal volume V and pressure P and temperature T. What work has to be done to increase the volume n times that of other ISOTHERMALLY?

Now I know that strong force holds the neutrons and protons together in the nucleus, electromagnetic force keeps the electrons in orbit around the nucleus, and how ionic and covalent bonding work, but what holds the atoms of, for example, my body together. I’ve looked on several websites and the best thing I could find was the google definition of cohesion.

Ladies and gentlemen. I give you my video on Supernormal Energy (SE)! (2 min video) https://www.youtube.com/watch?v=zYpokTXICjA&t=7s I will answer any questions!!

If a planetary body about the size and mass of Ceres were to be captured by the Earth could it take up a stable orbit around the Earth? How difficult would the interactions be for the Earth Moon system to capture such a body? Also would such a capture take several years of interactions between the Earth, the Moon and the new body or would it be more of an immediate thing?

Not sure if this makes sense, but I’ll just have a go at explaining it. Just bear with me. So out of curiousity: since all solids are compiled of clusters of atoms, then hypothetically speaking, will there always be empty gaps in any solid structure that would allow a hypothetical “string” of empty space to pass through it?

Radon doesn’t form many compounds. I think it will bond with fluorine but not much else that we know of. Radium will bond with nitrogen to make Ra3N2. Radium decays into radon, so what happens when the radium attached to nitrogen does that? I assume extra energy is released from breaking the bonds with the nitrogen, as radon can’t bond that way?

Is there any sense in the question "Can one clock measure another (less accurate) clock?" Does the latter clock become simply a set or series of events when it becomes thus the "measured " ?

I'll be honest, I don't know much about this. I know most of you reading this probably think this is a weird/dumb question. What I've read so far is that Electromagnetic vibrations travel strongly through the vacum of space, yet Water acts like a damper. Vibrations in water are considered Mechanical vibrations. What I want to know is there any way scientifically to enhance the strength of Electromagnetic waves in water. Even if there's an odd theoretical scenario where this is possible. Any help would be appreciated.

Hello Everyone.I need to measure "surface electrical charge(charge density)" of a paperboard. Do you know the name of instrument that I have to use?

So, I'm aware it's not possible to go faster than the speed of light, and that as something nears the speed of light it's mass increases, time slows down and bla bla bla. What I'm interested in knowing is, if something went faster the speed of light, how many laws of physics would it break, and if that happens (theorising time now boiis!) what do you think would happen? Would the thing go back in time, or would space-time warp around that object and create a wormhole or something even stranger. Even if you don't want to answer the 2nd part of the question, please answer the 1st part. Thx in advance.

I dont mean the dictionary definition. I mean, well, it seems sometimes that the word information is used in a very special sense in physics. Does it have a special meaning or is my perception off?