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Resolution Of The Heisenberg Uncertainty Principle

Hemos posted more than 13 years ago | from the resolving-the-the-position dept.

Science 50

bubblywatr writes: "A Caltech physics professor, Dr. Zewail, has apparently resolved the Heisenberg Uncertainty Principle (that the velocity and position of an electron cannot be determined simultaneously). He proposes in a recent issue of Nature(July 19: " The Fog that was not"), that one can solve, USING CLASSICAL PHYSICS (ie: f=ma), for the location and the position in space of a fundamental particle simultaneously by using FEMTOSECOND DATA COLLECTION (which can pick up atomic energy states), WHILE THE WAVEFORMS OF MATTER ARE IN COHERENCE (which minimizes the error of the femtosecond data because of the localizing effects of coherence). "

What does this mean? Femtosecond resolution apparently provides the localization needed to treat electrons as classical spheres in space, nearly following Newtonian physics. However, femtosecond chemistry has been around for years, so why hasn't this worked yet? Well, there is a great deal of error in gathering energy values, even when energies are collected at femtosecond intervals. This is due to freaky quantum physics i don't understand. But, as Zewail states, 'this freaky quantum error can be nearly eliminated if the matter is made coherent'. This means that the wavelike properties of matter are superimposed leading to the addition or destruction of waveforms. This is like the 'double slit experiment', in which regular light is shown through two slits, the waveforms either completely add or subtract, and what you see on the wall is a bunch of tiny spots of light at a defined point in space."

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Re:f=ma? (1)

Anonymous Coward | more than 13 years ago | (#2181175)

Luckily, this site [] is designed in such a way that even the likes of you [] have a chance of understanding it.

Re:measurement problems (1)

Anonymous Coward | more than 13 years ago | (#2181176)

Yes, this is classical uncertainty. Here we're talking about quantum uncertainty.

Clarification of Zewail's result (2)

Anonymous Coward | more than 13 years ago | (#2181177)

The first point is that the "Uncertainty" in the uncertainty principle is a bad translation from German. HUP is not about uncertainty in MEASURING two quantities that both actually HAVE values - it is about the fact that they can not simultaneously HAVE values at all. It's really about simultaneous existance, not simultaneous measurement.

The second point is that is Zewail had actually found a violation, or even a slight deviation from HUR, he would win massive instant fame. He has done no such thing, and does not even claim to.

He never mentions "F=M*A", and those concepts do not appear anywhere in the paper.

What he has really done is a kind of quantum mechanical analog to the Mossbauer Effect. The key in both cases is to realize that the coherent behavior of a large group is quite different from that of single atoms, and creates a whole different situation for measurement. This is yet another vindication of QM, and another reminder that QM is quite counter-intuitive, even for those who make a living at it.

Quantum Computers and Decoherence (1)

dido (9125) | more than 13 years ago | (#2181178)

b) coherence (which is needed for spatial localization) is not as instable (sic) as initially thought

Now, if this is true, then I guess quantum computation must have higher hopes then. The biggest problem with building a practical quantum computer is that in most physical quantum systems decoherence phenomena will randomize the state of your qubits before you can make any kind of useful calculation. Present research in quantum computing has focused on attempting to find physical systems where you can compute and read out the result of your computation before decoherence sets in. If a coherent quantum superposition is really more stable than initially thought (and as Zewail suggests), then a practical quantum computer might not be as hard as everyone thinks.

Re:God does not play dice. (1)

MrNixon (28945) | more than 13 years ago | (#2181179)

Most of Einstein's theory were based on math and have never been really proven

Its a theory. So it can't be proven. And most theories in physics are math - this isn't biology. If you could point us to a theory that explains the same phenomena as relativity (and does it as well), then I'd be more than willing to take it into consideration. But don't go around calling him a dumb Jew and using that as a reason to call his theory false.

Relativity supporters are not completely closed minded to something better coming around sometime in the future. But right now, it's the best thing we've got.

Re:Astounding (1)

MrCreosote (34188) | more than 13 years ago | (#2181180)

I know what you are getting at, but just a niggle. Speed is only one component of velocity - velocity is speed and direction.

Astounding (4)

p3d0 (42270) | more than 13 years ago | (#2181181)

one can solve, USING CLASSICAL PHYSICS (ie: f=ma), for the location and the position in space of a fundamental particle simultaneously
Wow! Now, if only they could find both the velocity AND the speed.

Re:f=ma? Last post I promise (1)

Old Wolf (56093) | more than 13 years ago | (#2181182)

Is anyone else enjoying how Genoaschild seems to have replied to his own post about ten times in a row?

Re:God does not play dice. (1)

Old Wolf (56093) | more than 13 years ago | (#2181183)

These are not proof at all (in fact they aren't even evidence). Consider the theory: "Gravity behaves like relativity says it does at the moment, but on 1 Jan 2050 it will suddenly become repulsive".

If you want your measurements to confirm relativity, then they must all confirm my theory too.

Re:some clarifications (2)

astrophysics (85561) | more than 13 years ago | (#2181184)

> No. The double slit experiment doesn't work with regular light, you need *coherent* light (e.g. a Laser).

Guess you didn't try this experiment in physics class. Anyone who wan'ts to see for themself, I recommend an ordinary Tungsten filament light bulb, a card board box, and two slits from a razor blade in a dark room.

Don't feel bad. An alarming number of my students in a junior level physics lab at MIT were suprised by this.

measurement problems (2)

frankie (91710) | more than 13 years ago | (#2181185)

great deal of error in gathering energy values, even when energies are collected at femtosecond intervals. This is due to freaky quantum physics i don't understand.

Simple explanation: How do you measure the energy value (tantamount to speed or momentum) of an electron? By looking at it. How do you look at it? With photons. What happens when a photon hits an electron? They trade some energy. What is it you were trying to measure? . . .

If you bombard a subatomic particle with other particles, and do it 10^12 times per second, of course you're going to have a hard time keeping the answer straight, because your measuring device is causing the answer to change.

Suspicious (2)

4of12 (97621) | more than 13 years ago | (#2181186)

Ahmed Zewail is quite the physical chemist, and I have a lot of respect for him and his work. However, I have to be suspicious of such a claim, which might just be journalistic hype for what little I know.

I have to wonder if there's a shell game, where "incoherence" is a synonym for rejecting those particles whose (x,p) values would pollute the probability distribution in favor of Heisenberg's inequality.

Re:Clarification of Zewail's result (2)

Perx (107558) | more than 13 years ago | (#2181187)

The second point is that is Zewail had actually found a violation, or even a slight deviation from HUR, he would win massive instant fame.

More than when he won the Nobel Prize in Chemistry in 1999?

Re: Resolution Of TheHeisenberg Uncertainty Princi (4)

Fredbo (118960) | more than 13 years ago | (#2181188)

But was he certain of that?

This is all great news, but... (1)

Colz Grigor (126123) | about 13 years ago | (#2181189) does it help me measure the performance of my systems without having to run a separate process to perform the measurement?

::Colz Grigor


Re:some clarifications (1)

thomis (136073) | more than 13 years ago | (#2181190)

I don't know why I feel sorry for Hemos, but here it is: when a story is posted text in italics is written by the person who suggested the story (in this case bubblywatr)while the slashdot staff post in plaintext. I'm sure Hemos makes enough mistakes without us attributing other people's to him.

Re:f=ma? (1)

supruzr (138432) | more than 13 years ago | (#2181191)

I'm sorry, but have you ever even studied relativity? Your conception of relative velocities doesn't hold anywhere near the speed of light. If two particles are going in opposite directions at 0.75c, the velocity of one relative to the other is NOT 1.5c, it's closer to 0.99c.

And maybe you've never heard of 'wave-particle duality' either. Go figure. That's pretty fundamental to quantum mechanics. Photons can act like waves or particles, depending on the situation. Light is NOT measured in waves, it's measured in quanta. That's another little nugget of fundamental quantum mechanics you neglected. Light has a wavelength, but that's not a quantitative measurement. Knowing the wavelength of some light will not tell you how much of it there is.

And the mass of a photon is not 'very tiny'. Photons are virtual particles. They have no mass, by definition. As far as different 'color' photons being of different 'masses', that's relativistic mass. Relativistic mass depends on velocity. Real mass doesn't. M = E_0 / c^2. E_0 is the energy of the object at rest.

Energy does not really exist? What is that supposed to mean? Do you know the difference between 'does not exist' and 'is not matter' ? Anything that affects reality in any way 'exists'. Of course energy is not matter. You could just as easily (and more correctly) say that velocity and mass do not exist, being spinoffs of energy. And I really have no idea what your last three sentences are supposed to mean, but I suspect you aren't familiar with the Constancy of the Speed of Light principle. If that's not what you're getting at, I certainly hope English is not your first language.

I strongly suggest you actually pick up a book and read something about relativity and quantum mechanics, because your seem to know about as much about the two as any American who has never read anything more in-depth than a high school physics text book. I personally recommend Hawking's A Brief History of Time.

Re:f=ma? (1)

supruzr (138432) | more than 13 years ago | (#2181192)

I'm really getting embarassed having to reply to these posts. You can't just keep 'zooming' in on particles and finding smaller particles, ad infinitum. There is a point where there are no longer any smaller particles, and modern quantum mechanics would have us believe that quarks are the bottom of the barrel. And I would hope your 20-page philosophy paper got a failure grade, because that has nothing to do with philosophy. It's metaphysics, and contrary to ignorant belief, they aren't nearly the same thing just because many philosophers were also metaphysicists. Philosophy relies on logic. Metaphysics is the use of unproved assumptions as a priori knowledge to interpolate other assumptions that, consequently, can't be proved. Metaphysics is mental masturbation. Anyone above the age of ten could disprove your theory, and I personally don't even think it's reasonable to believe it, let alone attempt to prove it. You're trying to compare planets with subatomic particles, which brings us to another FUNDAMENTAL PART OF QUANTUM MECHANICS, which is that it doesn't obey the same laws as the macro world. Planets and particles are not analogous in any way. Electrons do NOT circle a nucleus in the same way that planets orbit a star, and that's been commonly accepted for the last twenty years.

I also find it curious that you are mixing material particles and virtual particles in your arguments, as if they have anything in common. I believe you don't understand the fundamental difference between a mass-carrying particle and a virtual particle, and the fact that one cannot be expressed in terms of the other. You are trying to explain photons, which are virtual, in terms of electrons, which are material. Don't do that.

Re:f=ma? (1)

supruzr (138432) | more than 13 years ago | (#2181193)

Now I've heard everything. You're just being a troll now. You obviously have absolutely no idea what you're talking about, and despite all the corrections I could make on this, and future posts you make, I'm not going to waste my time, because it's apparent you are not capable of understanding physics or quantum mechanics.

And someone like you saying 'get a clue' is exactly the ad hominem crap I'd expect from someone who is willing to believe a priori that a theory is false, simply because they want to believe that. You certainly are a metaphysicist, and not a philosopher. You're only engaging in escapism to continue your line of thinking, and I've done my best to try to explain why the people that came before you that thought the same things abandoned their unreasonable theories. You have no grasp on many fundamental laws, and I will only cite one more. Ockham's Razor. You are certainly inventing unnecessary steps.

No matter how ad hominem your reply to my other post is, let me lay your mind to rest here: I'm not going to reply to it.

Re:f=ma? You are such a troll. (1)

supruzr (138432) | more than 13 years ago | (#2181194)

Ok, this is my last post on this thread, really. Now, I'm not stupid, Genoaschild. You don't have to flame anonymously like a baby, like it somehow reinforces your misguided banter. And speaking of one sided theories, perhaps nobody else reading this thread find it ironic that you, er, Genoaschild, keeps going on about how no theory can ever be proven, and yet you, er, he, accepts his ideas as proven fact. Now at this point, I know you, er, he, doesn't know what the phrase 'a priori' means. Because I've said it more than once, and it hasn't even made an impact yet. You, er, he, is contradicting himself. Now I really, really, really am not going to be dragged further into this quite childish flame fest, when anyone who reads the thread can plainly see you, er, Genoaschild, for what he is. A child who can't deal with being wrong. If you, er, he, can't see through his own ideas as being dated, and OUT dated at that, and you, er, he, doesn't have the sense to read a single history book to realize that he is about the twenty thousandth person to come to this line of reasoning, you, er, he, will have to be proven blatantly incorrect, and stupid to boot, the hard way. I won't do that further than I already have.

Uncertainty Haiku (2)

dankjones (192476) | more than 13 years ago | (#2181195)

I thought I had it

I observed the article

Now i'm not so sure.

Re:God does not play dice. (3)

nekid_singularity (196486) | more than 13 years ago | (#2181196)

I know that you are a pathetic troll, but I feel I should list the proof that Einstein's theory's have: The tiny precession in Mecurys orbit was explained perfectly by Special Relativity, the Gravitational lensing effect it predicted was observed, the time dilation has been proven in at least two ways, one that subatomic particles that should decay extremely rapidly when at rest last a lot longer when moving at close to the speed of light, and atomic clocks put on planes that rack up a great deal of miles run slow by exactley the amount einstien predicted. Finally, binary neutron stars slow down at a rate that is predicted by relativity from the energy loss of gravitational waves. The measured rate matches what the "dumb Jew" predicted to TWELVE or so decimal places. Its one of the single most succsessful theories in all Physics.

Re:f=ma? Last post I promise (1)

hamburger lady (218108) | more than 13 years ago | (#2181197)

If you are so correct then explain again why photons are attracted to black holes. If photons are virtual particles that have no mass, they shouldn't be attracted to gravity, now should they

because photons do have mass, just not rest mass. they have 'relativistic' mass. they have momentum. they have no rest mass because they are never at rest, duh.


Re:f=ma? (1)

esonik (222874) | more than 13 years ago | (#2181198)

The reason why electrons don't plunge into the nucleus are:

1) The Pauli Principle: Electrons at lower energy states prevent the other electrons from going there. The reason why something like "states" exists is the wave-like nature of particles (electrons), which give also rise to:

2) The Heisenberg Uncertainty Principle: If the electron would be at rest (in the nucleus, or anywhere) it would have infinite uncertainty in momentum, i.e. in the next instant it would be somewhere else (and you wouldn't know where). So it IS possible for electrons to be at the position of the nucleus, but only for a very short time (this leads to something called "Fermi-Contact-Interaction" between s-electrons and nuclei).

Re:some clarifications (2)

esonik (222874) | more than 13 years ago | (#2181199)

I hope you don't want to suggest that no coherence is needed for interference effects. In the case of a double slit experiment one needs a transverse coherence length of at least the slit spacing to see interference effects. I guess you use a pinhole between lamp and slits to reduce the source size and put it far away from the slits. What you then have is a light source with a certain transverse coherence (although it's not a Laser).
I think our problem is that "regular light" was not defined exactly enough.

some clarifications (3)

esonik (222874) | more than 13 years ago | (#2181200)

Zewail didn't "resolve" the Heisenberg Uncertainty Principle (HUR) (what does "resolve" mean in this context anyway ?). He has just pointed out why the HUR was not an obstace in femtochemistry:
a) it's a matter of numbers
b) coherence (which is needed for spatial localization) is not as instable as initially thought

for a) it's important to remember that he is talking about positions of NUCLEI which are quite
heavy objects (compared to e.g. electrons). Heavy objects have large momentum (p=mv) therefore a small uncertainty is not as disturbing as for light objects.

Now some comments on Hemos' text/questions:

Femtosecond resolution apparently provides the localization needed to treat electrons as classical spheres in space, nearly following Newtonian physics.

No, he is talking about "atomic motion", i.e. about nuclei. See above.

However, femtosecond chemistry has been around for years, so why hasn't this worked yet?

It has worked. The article is just a summary/explanation of why it has worked.

Well, there is a great deal of error in gathering energy values, even when energies are collected at femtosecond intervals. This is due to freaky quantum physics i don't understand.

The error is given by the HUR: Delta(E) >= hbar/(2*Delta(t)). The shorter you look, the larger the uncertainty. However, it turned out that the timescale of several ten femtoseconds is still large enough to have sufficient energy resolution.

This is like the 'double slit experiment', in which regular light is shown through two slits, the waveforms either completely add or subtract, and what you see on the wall is a bunch of tiny spots of light at a defined point in space.

No. The double slit experiment doesn't work with regular light, you need *coherent* light (e.g. a Laser). That's exactly the point Zewail makes: if they had used incoherent states (or if the coherency was destroyed fast) they would not have observed localized atoms ( = your "tiny spots of light")

Future Uses... (1)

TWX_the_Linux_Zealot (227666) | more than 13 years ago | (#2181201)

So that's how those damn Transporters work...

IBM had PL/1, with syntax worse than JOSS,

Hum (1)

BigGar' (411008) | more than 13 years ago | (#2181202)

Are they certain of this?

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181203)

You missed the point. Radiation are photons that have momentum and momentum=M*V. So if photons hit an electron and causing it to slow down, that would be deceleration. Considering the size of an electron compared to that of a photon, electrons are much bigger then photons so photons would need a much greater velocity to slow down an electron significantly.

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181204)

Mass does not exist in the form of energy. Via. the formula E=mv^2. Mass multiplies by a particles velocity squared. Second of all, you are forgetting about relativity and mediums. Light travels different velocities in different medians in a very thin spectrum of velocities. Light can travel faster in Vacuums than it can in an atmosphere. Relative velocity is another thing. If a particle is going 100 meters south and another is going 100 meters north then their relative velocity is 200 meters n to s. Another thing, light does truely travel in waves. It is MEASURED in waves. It is a frequency people. The time it takes from one particle to hit something until the next one hits the same object. Learn the difference.

On effecting the velocity of an electron. Momentum=MV. The mass of a photon is very tiny. It would take a very high velocity to change the course of one electron or millions upon millions of photons. I agree with you on this point. Anyways, the point is, Energy does not really exist. It is a measurement of velocity and mass. People always seem to forget about relativity when talking about velocities. All masses have relativity, even very small ones and that changes what the value is measured as. We are just so used to having approximately the same relativity because Earth and the stars are traveling relatively compared to the velocity of a light particle.

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181205)

Your argument about photons being definitely a particle is not really supported by a variety of neat experiments. It is supported by as many experiment as those that do not support it. Pure energy has never been proven to exist so logic says Photons must be in the form of a mass since everything else exists in the form of a mass.

I am not so happy with your claim that energy does not exist... one could argue that mass does not exist, it is merely energy condensed to a slow vibration. I could easily argue that too. I don't believe it but I could argue that mass does not exist. Their is also an interesting theory that mass does not exist(and I did a 20 page philosophy report on this(believe it or not)) on the basis that if you look at something like a proton and you zoom in really close, what do you find, a particle divided among many particles. If you look at one of these particles and zoom in farther, what should you theoretically find, a particle that is actually composed of even smaller particles. If you zoom in one of those particles, what should you find, a division among smaller particle. Repeat the cycle. So, in theory, their is almost no mass in a particle. Their are naturally problems with this theory and is based on a hierarchial system of zooming in on something like a galaxy. Anyways, everything we are argueing about are still in theory and none of them have been proven to the satisfaction of the world or becoming a law.

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181206)

I understand it better than you do. You are just trying to lop everything into two different categories. Particles that are pure energy and those who are not. Do this if you want to but you are just making a fool of yourself. Why should photons be any different then any other particles, Really. You are mixing predetermined theory with OPTs(other people's thoughts.) Science does not say that someone comes up with a theory without real world research and everybody believes it or does not try to prove it wrong. No, people do real research for and against. Everything we are talking are unproven theories and I think we should leave it at that. Repetition: Particles on a higher level act exactly the same way as particles on a lower level given the same conditions except on a larger scale.

As for my philosophy report, I got a pure A. It was an Arguement against St. Thomas of Aquinas fifth arguement in his five ways of St. Aquinas(the argument against Intelligent Design). It's completely theory with a lot of Umph behind. I'm not the person who came up with the theory or am I the one who keeps the theory going. Their are a lot of facts behind it. None, 100% conclusive but still, they exist. Everything we are talking about is still theory and most of it hasn't been proven. Until I see proof otherwise or actually have evidence for your case, I will be inclined to go against it.

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181207)

You told me to get a clue because I'm shouting out theory against your belief. I told you to get a clue because you are shouting out theory that has no evidence behind it, just one or two people. So be it.

Re:f=ma? You are such a troll. (1)

Genoaschild (452944) | more than 13 years ago | (#2181208)

Just because a bunch of people do something stupid, does not make it any less stupid.

I know what the hell 'Priori [] ' means, I'm just ignoring it. It relates more to you then me. Mostly everybody believed the world was flat once but is that the case. NO(I said that about 2 posts ago.) I agree with the Anonymous Poster, you need to have a more of an open mind. Something with as little proof as their is needs to be questioned. I spilled theory on your plate. I never said it was right. I said it had the possibility of being right. I don't agree with Einstein's theory of relativity because it has problems(too many assumed unproven theories.) I've read many Physics books and have taken several physic's classes and understand theory. I just don't agree with it. I'm probably in a better position to argue because I ACTUALLY UNDERSTAND PHYSICS. Their are more then one theory, live with it. Try to prove yours right. I'll believe it when I see it. Like I said earlier, everything we deal with are still theories. Just because millions of people believe something and continues the theory by researching it and building on it, does not make it more right. People will believe what they want to believe.

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181209)

One small thought: Momentum does not equall energy. They are related but they are not the same. Energy = Mass * Velocity ^2(Einstein simply replaced V with C in his famous formula E=MC^2 because it is generally a relative constant.) Momentum = Mass*Velocity. Small Difference. To assume you have momentum, you have to assume you have mass.

Energy is something that can be measured but isn't real as it actually exists. It is the product of several components. Einstein crossed the line and said Energy existed and could be converted to Mass and Mass could be converted to energy as what happened in the big bang. I don't see it. Energy has never been proven to exist without the existence of Mass. So far, you need mass to have energy and energy to have mass. If you set the m=0 in the formula Energy = Mass * Velocity^2, Energy suddenly equals 0. Suddenly, we have a problem. Anyways, my point is: either mass exists or energy exists, not both or it leaves the remote possibility of this formula being wrong. Science has yet to solve this problem conclusively.

Re:f=ma? Last post I promise (1)

Genoaschild (452944) | more than 13 years ago | (#2181210)

If you are so correct then explain again why photons are attracted to black holes. If photons are virtual particles that have no mass, they shouldn't be attracted to gravity, now should they. Yet, the fundamental concept of a black hole in fact that Black holes have such high levels of gravity(or the theory that Unifies Gravity, EM, strong, weak force, etc.(I can't think of it right now)) that passing photons don't have enough momentum to escape or orbit the ball of mass. Their is too much gravity and it may orbit a few times but each time it gets closer and closer because it is effected by gravity. Explain now that photons have no mass and that photons vs. electrons and the alike are somehow different. Do this to my satisfactory and I may actually take you seriously, supruzr.

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181211)

Have you ever thought of, I don't know, thinking for yourself. If you don't know how, generally, a fission bomb works, you are just fooling yourself. When it actually comes down to it, we really don't know. We know how fission works. We can split an atom and make two or more smaller ones. Unfortunately, we can't actually "see" what is happening as we split the atom because we can't see electrons or neutrons or protons or actual photons as we split it. So, we have to make educated guesses. Some sound more sci-fi then others that are based on other theories while others try to explain the release the energy using a hierarchial system, in other words, using larger models instead of trying to explain that their is just energy released during the process without reason of how this energy travels or how this energy is stored or stating that energy can be somehow changed to mass and vice versa. If you can't see something and are only making educated guesses, you really don't know. Yes, we explain the fission using the strong and weak force and we know energy is released. This is not the controversy. The controversy is, is their anything special about light and its velocity? Since light is theoretically limited by the EM force, if you eliminate EM, we should be able to go faster then light. And what's with relative velocity? We have a highly sci-fi and highly unproven theory that relative velocity disappears at the speed of light. I think it's highly bullshit that their is any such thing. It wouldn't make sense in an infinite space. Anyways, my point is, we really don't know, we can only theorize and their are more then one theories to try to explain the unknown and myself offering one to you that might have the possibility with some research behind it does not make me a troll.

Just because someone has a difference of an opinion than you does not make them stupid or a troll. I'm actually quite an intelligent person(I don't use the preview button before I press submit and check my mistakes) but I'm still an intelligent person with an opinion and you sir are a Lemming.

Re:f=ma? Last post I promise (1)

Genoaschild (452944) | more than 13 years ago | (#2181212)

I'm trying to prove to the guy in the above post that photons have mass people. Do you even read the previous posts? Also, in theory, a photon might be at rest in relationship to another object.

Re:f=ma? Last post I promise (1)

Genoaschild (452944) | more than 13 years ago | (#2181213)

Can you prove time exists? If not, don't reply to this question.

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181214)

On one hand, you are an idiot.

On the other, you are _not smart_. On the other hand, I am smart and you are dumb. Dumb I say. Anybody else enjoying this more then I am. I get sick of dumb people who call other people dumb because they have nothing better to do and instead of trying to refute someone elses claim, they resort to name calling.

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181215)

I'm just really bored and have pretty much run out of stuff to say. He started it and I'm bored enough to reply because I stopped giving a shit. Anyways, your point with the Theory of Relativity is well-taken. I still don't agree with it and still think Einstein got too much credit for his work and people are willing to shove Einstein up to God status.

You can find many people who will refute any given theory, and seemingly quite intelligently. The trick is finding one of these people who isn't a raving paranoid looney. There are plenty of people out there with websites who can give you reams of evidence that everything you know is wrong, but then discredit themselves by claiming the government killed their dog to shut them up, or claiming that satan lives in their microwave. Their are also people who are willing to jump off a tall building because a comet passed near the Earth, doesn't mean the majority is right, it just means it is more accepted.

I didn't know that. I guess all this quantum mechanics stuff is bullshit. I never ditched Quantum Physics. I actually agree with 99% of it. I'm sure most of it is true. Since we can't really see electrons, we can pretty much guarantee that not all of it is going to be true but most likely, most of it will be true.

As for f=ma, it was the first thing that popped into my mind. I could've came up with a better formula like d=do +vt+1/2A*t^2+1^/6dA^3 +1/24dda^4+1/120ddda^5 + ... or something like that. That formula is still not impressive. Most physic formulas are not that complex nor are they impressive so which one are you going to choose.

As for the cursing and shit like that, I just do it because I'm bored and having nothing better to do. If I wanted to be professional, I would. Fortunately, this is a publc forum and I can say whatever I want.

Re:f=ma? (1)

Genoaschild (452944) | more than 13 years ago | (#2181216)

So I'm inconsistent, I really don't care. Unless you are going to talk to me in person, I really don't care. What are you going to do, track down my DHCP IP address. Does /. log them? Anybody know? Anyways, if I wanted to be consistent and I actually cared and wasn't so bored to actually reply, we wouldn't be having this conversation, now would we? As for "Dude, Where's my Car", I haven't seen it. As for MP3s, I'll listen to them in a very rare while when I'm really bored. Another thing, I'm much nicer when I'm not replying to an Annonymous coward. Try getting a user account. We could discuss the theory of relativity all day but it is really getting old and what is this, my thirtieth post on my subject. Another thing, it is a public forum, if people can't handle some curse words(as on South Park "words of curse", oh my god, you killed Kenny, you bastard) then they shouldn't be here.

Anyways, this forum has been the longest one I've ever replied to. Do you really want to know the truth about me? Here it goes. I like to piss people off. I like saying things to get responses. I like to argue. I don't care if I'm right or not or if the other person is right or not(I'm still going to dispute Einstein's theory of relativity because it really assumes too much how things are(as I said in an earlier post, the math might be right that explains a phenomenon within a specified range but the reasoning behind it still might be wrong)) I just like to argue. I'm sorry for calling you stupid, I don't know if your stupid or not. If you can even understand Einstein's theory of relativity, you must have atleast an IQ of 120 which is better then most people. Anyways, argueing is fun, don't you agree? I love to argue. I'll go down a path that I know is completely wrong if I can argue it and if asked a question against myself, I would argue it too. I just enjoy it that much. I'm really quite intelligent when it comes down to it. I haven't got where I've gotten in life by being stupid(in other words, I didn't join the Army.)

The main points I have against the theory of relativity include:

1) Is their anything really special about the velocity of light.

2) Why would relativity at the speed of light change when the relativity below the speed of light is normal.

3) The space-time continuum problem. Does time exist. In other words, can we make time non-linear. I have yet to see proof of this.

4) The energy->mass->energy conversion problem.

It's been fun but I have to go.

Re:enter pot, stage left... (1)

Genoaschild (452944) | more than 12 years ago | (#2181217)

OK, this is interesting. I only call people retarded when they really desrve it. Besides, you started it.

Re:God does not play dice. (1)

Iondrivex (464492) | more than 13 years ago | (#2181218)

Not completely closed! That's a gross understatement. We spend a few billion a year on supercolliders to amend the theory of relativity, in the search for the Grand Unified Theory, which should reconcile Quantum Mechanics and Relativity. BTW, I'm not a physicist, but I've done my hw, and last time I checked the only time relativity fails to produce through equation what we observe in reality is in the super-microscopic. Also, lets look at a few things: 1. It is pretty well understood that a theory is very nearly a fact in the scientific community. 2. Math is an extremely powerful tool, that is more accurate than any instrument possible. It lets us model natural systems in incredible detail, and give incite into how to prove a hypothesis. Don't knock it. 3. If you're going to play around with the denotations and conotations of words, please look them up first! And I move to amend the troll's name to "Nazi-Hate-Monger Troll."

Re:God does not play dice. (1)

Iondrivex (464492) | more than 13 years ago | (#2181219)

You completely missed my point. Completely missed it. You are millions of Parsecs from it. Wow, now it takes talent to be that oblivious.

Re:f=ma? (1)

veinard (469297) | more than 13 years ago | (#2181220)

I'm going to be all nit-picky and say that electrons are pretty darn small, essentially point particles, while photons are just energy so they have no size, so the size argument doesn't make any sense. Furthermore photons really only travel at one speed, c (the speed of light, go figure), so they are often going much faster than electrons unless you've got highly relativistic electrons. However, their frequency (not their speed) defines their momentum, as a blue photon has more momentum than a red photon: p=h/lambda (where lambda is wavelength).

Pretty sure though that your average blue photon (lambda = 400nm) has p=10^-28 kgm/s about, while an electron will have between p=0 .. 10^-25kgm/s at non-relativistic speeds... of course above a certain speed you end up in relativistic realms where you have to multiply the whole thing by gamma, but I digress. Guess my point is... a photon or a bunch of them can certainly affect the momentum of an electron.

hell... I could be wrong... I haven't been in school for a while.

-your sig, it taunted me!

Re:f=ma? (1)

veinard (469297) | more than 13 years ago | (#2181221)

Well... I wasn't forgetting about relativity, just misinterpreting slightly. the medium argument, yes i was forgeting about that. Your argument about photons being definitely a particle is not really supported by a variety of neat experiments.

A single photon can still have a "frequency" and thus a single quanta of energy, momentum or "mass," if you will, one can definitely produce single photons of different energy, or momentum (for you who does not believe in energy), in the same medium; its done everyday and it is even measurable. Frequency can be merely a way of expressing the amount of energy or momentum a single photon has.

I am not so happy with your claim that energy does not exist... one could argue that mass does not exist, it is merely energy condensed to a slow vibration. Anyway... these are fairly fundamental things and the only point of my post was really to say that I do remember relativity, albeit imperfectly.

Comment+Clarification (3)

bubblywatr (471869) | more than 13 years ago | (#2181222)

Indeed some clarification is in need:

First, Zewail apparently has been pushing these ideas for some time, and Nature just gave him the opportunity to get it publicized a little. This is theory, people aren't going to go simultaneously calculate position and velocity of fundamental particles this afternoon, but he theorizes that with these two conditions met, such a characterization could be possible. As far as I understand, that is all he is claiming.

Second, when I said "he proposes in a recent issue of Nature...that one can solve, USING CLASSICAL PHYSICS (ie: f=ma)..." the (f=ma) is an EXAMPLE of what classical Newtonian physics is. I am not sure how that got misunderstood, but I apologize for my ambiguity. Perhaps it would have been better to simply quote Zewail as I will do now: "But if these waves are added up coherently with well-defined phases, the probability distribution becomes localized in space. The resultant wave packet and its associated de Broglie wavelength has the essential character of a classical particle: a trajectory in space and time with a well-defined (group) velocity and position - a moving classical marble but at atomic scale!" (Nature 2001, 412, p.279).

Even if my explanation was convoluted, I simply hope to get across Zewail's main idea: that quantum uncertainty is no longer an obstacle, and therefore openening the theoretical possibility for the resolution of HUP.

Raising an eyebrow (2)

pixelated77 (472348) | more than 13 years ago | (#2181223)

Somehow this feels oddly familiar to the Fleischmann & Pons scare of '89

Re:f=ma? Last post I promise (1)

Messica (472664) | more than 13 years ago | (#2181224)

Any massive object bends space-time, light rays appear to be bent by massive objects but really they are following a straight line and it is space-time which is bent in that area. The bending is so extreme around black holes that light doesn't escape a circular path.

The quick and dirty proof of photons having no mass is from E=mc^/sqrt(1-v^2/c^2) which is the correct Einstein equation. (It is so frustrating that people insist on using E=mc^2, which is only a special case) You can see that in a vacuum v=c, therefore E=infinity unless m=0. Obviously infinite energy is impossible so m=0. If m=0, then E=0/0 and 0/0 is an indeterminate number which is allowed, but doesn't give a solution. You can't use this equation to find the energy of the photon. For that you have to use the QM equation E=hf. For a good FAQ on the topic see html
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