Physics

Brownian motion requires relatively large 'walker', which is constantly being pushed in random directions (no memory) - it's derived as infinitesimal limit of Generic Random Walk (GRW) on a graph(lattice), in which each outgoing edge is equally probable. But let's imagine we want to estimate probability density of positions of some entity which doesn't just constantly 'stop and make new independent decision', but make some concrete trajectory, which for example could depend on the past (by e.g. velocity) - in such situations the safer than taking statistical ensemble among single edges as in GRW/Brownian motion, should be using statistical ensemble among whole possible p…

Some people say universe originated from nothing, some reject this. Is there any consensus about it. Or till no consensus?

suppose we have a gas that becomes completely ionized at room temperature, only energy in atmospheric gases are enough to convert it into plasma, since plasma loses energy by radiation to the surroundings, we could harness the generated electromagnetic energy violating the second law of thermodynamics.

I've been watching a lot of pelicans fly lately and I observe how they barely flap their wings as opposed to other birds flying around the area. Then, between beers, I thought of some kind of helium suit with flexiible wings. The wings, just like birds, would be made of a hollow ultra light metal skeleton. The suit itself would also have various compartments pumped with helium, kind of like how soldiers have pockets all over to distribute the weight. Does anyone think that with something of this type and jumping off a plain it would be possible to just fly around and chillax kind of how pelicans do.

Hello scienceforums.net, This is my first time posting on this website, for I have only discovered it today. I am 16 years old, and I wish to teach myself Physics and understand the basic principles, along with more complex theories and such in the near future. Due to the fact that my school doesn't teach Physics until senior year, and that I want to be ahead of the game because I'm genuinely fascinated by science, I've ordered a "Holt Physics" textbook. I plan on reading and studying out of it, but because I'm completely new to studying Physics, I don't know which actual topics will be paramount to learn if I wish to delve into the deeper areas of Physics such as Quant…

http://www.forbes.co...rave-new-world/ "Over on Network World where I've had a gig as a columnist for about 18 years, my Backspin column I wrote this week about a power generation system called E-Cat that is to be tested on October 28th. If you've missed the recent brouhaha over the E-Cat (which stands for Energy Catalyzer), you're missing out on a three ring circus over a technology that will either change everything or change nothing because what is promised is, in theory, power too cheap to be worth metering. The E-Cat is a simple device albeit with functioning that defies all known explanations. In summary, the E-Cat is a cold fusion (CF) device (the i…

Okay, recently, I've wondered how many choices on can make. So I did some research. If there was a total of 50,000 different things you could do (regardless of how long they take to perform) instantly (in this case per millisecond) You could perform 50,000^50,000 different choices per second if reality updated every millisecond. Or just to give you a basic hint of how many different choices. 93132257461547851562500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000…

Hello, My name is David Malcum, but my friends call me TJ. I am a time traveler from the year 2167. I was sent by the Temporal Historical Society. If you have any questions for me about me, or the future I would be happy to answer them, including science and technology. I have almost nothing to hide.

hello everyone my name is abed haidar , i am currently a second year physics student and i just want a brief summary about mechanical analysis thank you

I'm interested in new materals with interesting properties. Recently online Iv'e seen a paint that is transparent when over 27°C and one that is transparent when wet. It's occured to me that a building painted with three layers of paint that are normal, then thease two paints could appear one color when dry, another in the rain and a 3rd when the weather is hot.

According to quantum tunnelling an electron takes every possible path? Reading Brian Green's book - the elegant universe - he mentions that when Heisenberg was toying With the uncertainty principle he encountered quantum tunnelling where positrons and/or electrons have no exact position and momentum that can be measured. But i thought penning traps did just that? If so, how did penning trap electrons and indeed anti-matter for upto a week if it's exact location AND velocities cannot be measured?

The drift velocity of electrons is very small, approximately 1 mm/s. Then why light turns on instantly when switch is pressed? Is is due to the fact that electrons transfer energy to one another and thus conduct electricity without physically moving from one point to other?

I had done a experiment at my home.In the normal water from my tap, i found that it conducts AC but not DC,why?

Is Einstein Wrong? read more: Physicists have a stock phrase they trot out whenever someone claims to have made an astounding new discovery about the universe. "Important," they say, "if true."

I have just had a go at an a-level physics past paper, (a bit ahead of time I might add), and one of the questions i had no clue on was a circuit diagram with 4 cells, each with emf 1.5V (negligible internal resistance), and 3 resistors, giving a total circuit resistance of 6Ω. The resistors are not a worry (as I can work out the total resistance, although I know the total resistance will be needed), but the cells are confusing me. The circuit was arranged thus: Two cells in parallel with each other, two cells in series, and those two elements in series with each other. I do not know how to calculate the total emf of the circuit from this information, as I don't know …

http://en.wikipedia....hahdaei_Paradox The thought experiment in this article concerns one frame moves within an inertial frame and the other frame due to large be with good approximation be inertial... Very thankful for expert or others view.

I have just read Fank Close's Antimatter book and he mentiones anti-gravity several times. It doesn't however explain if antimatter or antiparticles adhere to positive gravity. Sorry if this makes little sense. Also do quark charges simply reverse in anti-particles? ^^v to vv^?

how would an oscillating magnetic field effect hydrogen?

I came across this while reading--If an object approaches/moves away from a mirror with velocity v then the image approaches/moves away from the mirror with velocity 2v. Isn't this wrong? The image should approach/move away from object with 2v rather than from mirror. Thanks.

plzz am looking for this book mastering physics by young freedman

Suppose I set the apparatus like this (image). Now I switch the key at the same time as I move the magnet towards the coil2. What would be the amount of current induced in coil 2?

What are the factor that influence the rate of the reaction in which decays carboon 14 into nitrogen-14? Does heat or radiation can have impact on the rate.

OK, so I decided to buy a new fan, and got a physics related question. For the breeze of a fan, should I be looking at the volume per second, at the velocity blown, both of those, or perhaps something like the kinetic energy of the air expelled (ie, (1/2) * volume/second * velocity^2)? Assume I want a good breeze. On a related note, I recently bought (but may return) a "high velocity" fan (Lasko 4940), though from looking it up it only has about 350 cubic feet per minute (CFM) on high. However I noticed it produces a decent breeze even at a distance. I think the kinetic energy of the blown air is catching more air along the way and draging it along, producing a strong…

would aluminium powder ignite if you put it in a microwave oven?

Are multiple universes a consequence of a standard theory of the universe or a more complex harder to prove theory i.e. the multiverse theory. And also does anyone know what the possiblity is of matter arranging itself in such a way as to be the same or at least very similar to our own universe. Thank you.