Quantum Theory

Very often people come to these fora with a belief that our current theories of physics, such as the Standard Model or relativity, are flawed and present some alternative of their own. On the whole, this is a fine attitude to take - we should always be skeptical, and it is good if people can think a little 'out of the box' and generate ideas which more standard thinkers may not have come up with. I have always thought that genius was not an ability to think 'better' than everyone else - it is an ability to think differently from everyone else. However, when coming up with a new theory it is important that it should be better than the old one. Therefore the first step …

Hello, I have read many posts where I find the above expression (Most notably from Mordred) but I only encounter it as part of explaining some other topic. Could you please expand on this with more information? It is a really interesting subject for me.

I find this subject interesting , yet at the heart of quantum theory. If anyone has any eureka feelings about " spin" at the quantum level please could you share them !

the question that dwells on almost any physics professor, of philosopher's mind is "Is time travel possible?" Well, why shouldn't it be?? We all are in fact time travelers ourselves. We all move forward in time, well, at least we all perceive to be moving forward in time. In fact, when you really think about it, we could all be moving backwards in time...time may not be moving at all. It could be stopped at the very moment that I am writing this...Of course you'll say "that's impossible, if time has stopped, how can I be reading this??" but we are forgetting the fact that maybe time has stopped for someone else. After all, time travel has a lot to do with perceptio…

In the double-slit experiment, what collapses the wave-function? The act of measurement? The information obtained from the measurement? Or the observer contemplating the information obtained from the measurement? The first is physical, the second informational and the third attributable to consciousness.

I don’t know the math behind time, but I feel that time is something that is always changing. So to try to come up with the math that makes it work with all the others I feel is the lack of understanding. I want to look at it as if it was sound. Sound when it goes out and comes back gets weaker every time until a new sound is added. So can time change the same way as sound. If this is the case the more you are always from an object in time the less it effects time. The same as sound gets weaker as it moves as does gravity. So if you wanted to bend time would not you only have to mass the effects that objects have on other objects. To me time is like a river if you place…

I have a question about the shape of the wave of a single photon entering the double-slit experiment, in time and space. Although I thought it was basic, it seems to be difficult because I did try other fora and Wiki, but nobody could give an answer. This is my last shot. Of course the interference pattern shows the shape, the envelop, in time. But because I don't have accurate measurement data (most pixtures of the pattern are simple and idealised) I cannot construct it from there. So I wonder if there is the (rough) formula, only as an approximation. Not exactly, because that will probably be of a high mathematical level.

LIGHT We do know that photons behave like a wave and a particle both, that's what particle wave duality tells us.. 1)So which source of light behave likes a particle and which one like a wave, How do we know that?? 2)If a particle has larger wavelength it behaves like a wave and the one which has smaller wavelength behaves like a photon? 3)Photons have momentum, p=hv/c, do wave have some momentum? Electrons Electrons are present around the nucleus of an atom(we all know that) 4) Are they present there as particles, standing frequency, clouds or on orbits(which is the least i would prefer) ??

the aim of this thread is to gather essential information from all quantum gravity-related threads into one, to get some focus Links to other SFN threads will be provided, and links to outside sources Smolin: How far are we from the quantum theory of gravity? http://arxiv.org/abs/hep-th/0303185 Rovelli: Quantum Gravity Cambridge Press 2004 http://www.cpt.univ-mrs.fr/~rovelli/rovelli.html Smolin: Invitation to Loop Quantum Gravity http://arxiv.org/hep-th/0408048 Ashtekar Lewandowski: Background Independent Quantum Gravity; a Status Report http://arxiv.org/abs/gr-qc/0404018 Smolin: Scientific Alternatives to the Anthropic Principle http://arxiv.org…

im not really sure what category this should come under but anyway: recently i saw in a newspaper that some scientist had teleported the properties of an atom, they'd teleported things before, but nothing as big as an atom and nothing as complex as an atom either here's a link to a website explaining what they did/found: http://news.bbc.co.uk/1/hi/sci/tech/3811785.stm it says that this is an important break through because althought they are still a long way off teleporting humans, they could use it to teleport data in computers instantaniously but what i was interested in was how they did it... they used a method called 'quantum entaglement', by w…

Getting my head around this, a particle is an excitation of its appropriate field, but what is the nature of that excitation? It does not wash as an oscillation, as such it would either generate a continual wave or the particle would cease to exist. It seems to me it must be a perturbation of the field extending to infinity via the inverse square... am I on the right track?

is the multiverse shown in the Michael Chrition Book timeline real or made up

The new Large Hadron Collider is coming online soon. It is said to be able to create micro black holes. I immediately admit that any knowledge I have about micro black holes comes from the main stream media (including wikipedia), and is therefore not very good. So, I read about the Hawking radiation, which states that the speed at which a black hole is emitting matter (the rate at which is loses weight) is inversely proportional to its weight. According to this theory, the micro black holes are harmless, because they will in fact lose all their matter so fast, that it might seem a small explosion. http://en.wikipedia.org/wiki/Micro_black_holes But, I also read…

I have been searching for the answer to the question of whether either observation or consciousness can influence the outcome of the double slit experiment for several years now and I feel I have made a lot of progress in understanding the problem but I have possibly reached the limits of my expertise to come to any definite conclusion except to say that this is an extremely thorny issue with no easy answers. It is my understanding that it is nearly the mainstream conclusion that observation and consciousness can influence the outcome of the double slit experiment. I have little interest in the philosophical or psychological aspects of this issue as long as th…

do photons have mass? i always assumed that since they have no rest mass, they have no mass. i wanted to find out so i did a little math. i took [math]E=hf[/math] and [math]E^2=m^2c^4+p^2c^4[/math] and put them togather. i got [math]m=\frac{hf}{{c^2}{(1+c^2)^{\frac{1}{2}}}}[/math]. when i solved, i found that the mass was zero. i took a closer look and saw that that wasn't true, for if i put 0 in for m, the photon would have 0 energy. then i decided to put in a stupidly high value for the frequency and i found it DID have mass. it is just so close to 0 at normal frequencys that you don't need to worry about it. i decided to pick a mass and find the frequen…

I read the kinetic energy of a photon goes to infinity when a photon reaches c. Is that possible?( E=hf ) Does the wavelength/frequency of a photon changes depending on the medium?

Theoretically, if an object has 0 kinetic energy, then it would mean that it's time stops, but, that same thing is exactly what happens in measurements in quantum mechanics. When we measure a particle, we are measuring a single finite and "not moving" point, its just a point, and since it's just a point and it's can't be moving because it would mean that your measurement is somehow getting information of it's motion before photons reach our eyes, it has 0 kinetic energy, so couldn't the reason why there's all this measurement weirdness be because a million times a second we are technically "stopping time" and therefore giving something 0 energy, and since it doesn't have …

Laymen and hobby student of physics here. So the only things I know (or at least think I know) I watch from documentaries. In the test to see if an electron is a particle or wave, they say that if you place a viewer before the slits that the resulting pattern on the back wall is a particle result. But if you aren't placing a viewer before the slit the resulting pattern on the back wall is wave interference. So how is watching the result on the back wall itself NOT placing a viewer thereby always causing the electron to act as a particle? Thank you in advance! Patrick

Is there an answer? If not please share your opinions! A hypothesis I am developing can only be quantized by the smallest possible mass, I cannot locate any information...

I just recently found out that Schrodinger made his thought experiment as a criticism of wave function collapse, and tried to illustrate how absurd it was by saying a cat is both dead and alive simultaneously until observed. So when people try to explain uncertainty of something with Schrodinger's Cat, are they using the incorrect analogy to describe the moment of uncertainty? ~ee

Atoms do not touch eachother and electrons repel each other therefore what we feel when we touch something is the feeling of repulsion between electrons.. Do you agree with it?

I've been searching around for the closest anyone's gotten to absolute zero... I can't find it now (forget what I searched for lol) but there was one dated 2003 that said 500 picoKelvins... I just want to know exactly how close to absolute zero anyone has been able to reach...

Should the [current] inability to "measure" position and momentum mean that a particle at a moment in time does not have a given position and speed?

Classical mechanics says anti-matter is matter bur the electrons are orbiting the other way around the nucleus, which we now know with quantum mechanics that an electron doesn't actually physically orbit the nucleus, as far as we know, and since the direction of the spin of an electron doesn't change its charge either, what causes the creation of anti matter quantum mechanically, and what causes the charges to reverse?

I registered only to post this question as it's bothering me since yesterday. So.. I was watching Discovery Science and saw in a show that scientists are trying to send info in the past. A guy was saying that when this will be possible, they will be able to send messages back in time and prevent many major events that happened in history. Now this is where I don't understand it anymore. How come we didn't receive any message from the future? Our present and our past is the past of their future. Hope you understand what I mean. ( English not my natural language ) So how come all the major events still happened if "we" from the future didn't send any information bac…