New technique excites atoms and molecules using pulsed laser

Nov 22, 2012
Stylized representation of the excitation of a single ion in a trap by means of a "hyper" Ramsey pulse sequence. Credit: PTB

The best method to obtain the most precise information on the inner structure of atoms and molecules is to excite them by means of resonant laser light. Unfortunately, just this laser light (above a certain intensity) can lead to measurable modifications within the atom's electron shell. Scientists of the Physikalisch-Technische Bundesanstalt (PTB) have now shown experimentally how to prevent such "light shifts". This confirms the advantages of "hyper" Ramsey excitation that had already been predicted theoretically. This method can make their optical ytterbium atomic clocks even more accurate. Furthermore, "hyper" Ramsey excitation can be helpful in numerous applications where the focus lies on a precise, controlled interaction between atoms and laser light. The results have been published in the current issue of the scientific journal Physical Review Letters.

"Light shift" means that intense laser light modifies the position of the ; the shift depends on the intensity and the wavelength of the laser used. If one is seeking the properties of the atom as an undisturbed , this shift must be either prevented or corrected. With the new procedure, which has been applied experimentally for the first time at PTB, a sequence of judiciously selected laser pulses used to excite the atom eliminates the disturbing light shift effect.

The basic idea of using pulsed radiation to perform goes back to Norman Ramsey, who was awarded the in 1989 for this finding. With this method, a first laser pulse is shot at the atom, where it starts a resonant excitation. Then the pulsation excited in the electron shell of the atom continues undisturbed "in the dark" until eventually a second laser pulse completes the comparison between the of the atom and the laser frequency. A similar approach is also usual in clock comparisons: two clocks are set to the same time, they are then left to run on and are eventually compared again. The result shows which clock was faster or slower than the other.

The signal of the Ramsey excitation contains, due to the dark phase between the laser pulses, an averaging over the positions of the states of the atom with and without a light shift. In principle, it would be possible to compensate for the light shift by modifying the by exactly this quantity (exclusively) during the pulses. This, however, would not bring great improvement from a practical point of view as the precise information concerning the disturbance of the atom should be known to begin with. In 2010, a group of scientists (also with PTB's participation) suggested a method they called "hyper" Ramsey excitation in order to solve this problem. This theoretical consideration has now been confirmed experimentally for the first time. In the case of "hyper" Ramsey excitation, a third laser pulse of the same intensity and the same frequency, but with an inverted phase, is inserted into the dark phase. This third laser pulse automatically compensates for possible errors which could occur due to misjudgment as regards the size of the light shift and due to small variations in the laser intensity during the light pulses.

Realizing "hyper" Ramsey excitation experimentally succeeded in an atomic transition which allows very slight frequency variations to be detected and, at the same time, exhibits a large light shift, since a high laser intensity is necessary for its excitation. It is an electrical octupole transition in the Yb+ ion which is being investigated as a basis for an optical clock. The experiment confirmed the theoretical predictions concerning the advantages of "hyper" Ramsey excitation and attained a 10,000-fold suppression of the light shift. This opens up the possibility for the optical Yb+ clock to achieve even greater accuracy. This method could also be interesting for other researchers trying to obtain a precisely controlled interaction between atoms and , for instance in the field of quantum information processing.

This allows them to remove an important obstacle in the development of even better optical atomic clocks, because the stability of the lasers used is a critical point. The "pendulum", i.e. the swinging system of such a clock, is a narrow optical absorption line in an atom or ion, whose transition frequency is read out by a laser. The linewidth of these transitions typically amounts to a few millihertz, a value which could not be reached by glass resonators due to their limited length stability.
But this is now possible. The to which the silicon resonator is stabilized reaches a linewidth of less than 40 mHz and can, thus, contribute to moving into a new dimension in the development of optical . This work could also benefit optical precision spectroscopy, another focal point of research of the Excellence Cluster QUEST.

"For the future, there is still room to improve the optical mirrors whose thermal noise limits the achievable stability", explains PTB physicist Christian Hagemann. Therefore, the researchers will in future go down to even lower temperatures and use novel highly reflecting structures to improve the frequency stability by another order of magnitude.

Explore further: What's next for the Large Hadron Collider?

More information: Huntemann, N.; Lipphardt, B.; Okhapkin, M.; Tamm, Chr.; Peik, E.; Taichenachev, A.V.; Yudin, V.I: Generalized Ramsey excitation scheme with suppressed light shift. Phys. Rev. Lett. 109 (2012) 213002. link.aps.org/doi/10.1103/PhysRevLett.109.213002

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johanfprins
1 / 5 (5) Nov 23, 2012
A great experiment: I hope the experimenters will finally realize that the smallest-energy laser pulse they can generate is a photon; and that therefore a photon is NOT a "particle".
antialias_physorg
4 / 5 (4) Nov 23, 2012
and that therefore a photon is NOT a "particle".

No one has claimed that the photon was a particle since the early nineteenth century.
So if you're waiting for some 'admission' as to this fact you're 200 years too late.
ValeriaT
1 / 5 (5) Nov 23, 2012
Most of objects around us are particles, so why just the photon should be an exception?
johanfprins
1 / 5 (6) Nov 23, 2012
and that therefore a photon is NOT a "particle".

No one has claimed that the photon was a particle since the early nineteenth century.
So if you're waiting for some 'admission' as to this fact you're 200 years too late.
Are you agreeing that it is not a "particle"; and that the schizophrenic concept of "wave-particle duality" is lunatic? Thanks!
antialias_physorg
5 / 5 (5) Nov 23, 2012
Are you agreeing that it is not a "particle"; and that the schizophrenic concept of "wave-particle duality" is lunatic?

What is lunatic about it? A photon is some entity that has some properties that appear to conform to a wave analogy under some conditions and some other properties that conform to a particle-like analogy under other conditions.

That it is called a wave-particle duality is not meant to suggest that it is a wave or a particle (or limited to ONLY exhibiting wave-like and particle-like behaviours. E.g. Photons can be entangled which is not specifically particle-like nor wave-like behavior.)

The duality only says that you can make experiments where it seems like a particle and others where it seems like a wave. Nothing more, nothing less.
johanfprins
1 / 5 (3) Nov 23, 2012
Most of objects around us are particles, so why just the photon should be an exception?
All objects (matter and light) around us are waves: They can be rudimentary coherent-waves (like the photon and the electron) or built up from an entanglement and/or superposition of waves. All of them, when not experiencing a change in boundary conditions, move through free space following a definite path: This does NOT make them "particles": Just as the sun, earth, Jupiter etc. are not "particles".

I have asked many times on this and other forums for a definition of what a "particle" is which can be used to distinguish it from a freely moving wave: None has been forthcoming ever except to claim that the photo-electric effect and Compton-scattering demands that it must be so. THIS IS NOT THE CASE: These two effects can be perfectly modeled in terms of the same wave-wave interaction that occurs when an orbital electron absorbs a photon to be excited into a higher energy electron-wave.
johanfprins
1 / 5 (7) Nov 23, 2012
What is lunatic about it? A photon is some entity that has some properties that appear to conform to a wave analogy under some conditions and some other properties that conform to a particle-like analogy under other conditions.


Define for me what is the "particle-analogy" that a photon-wave cannot conform to? Why make a distinction when you cannot even define what a "particle" is; and while it is indisputable that a photon-wave can follow a definite path when it moves through free space?

That it is called a wave-particle duality is not meant to suggest that it is a wave or a particle (or limited to ONLY exhibiting wave-like and particle-like behaviours. E.g. Photons can be entangled which is not specifically particle-like nor wave-like behavior.)


A coherent wave can split into two parts while remaining a single wave so that the two parts remain in intimate with one another. This is NOT possible for "particles".

Only a psychotic-schizo will believe you!
johanfprins
1 / 5 (6) Nov 23, 2012
The duality only says that you can make experiments where it seems like a particle and others where it seems like a wave. Nothing more, nothing less.


I know of no physics that cannot be modeled entirely in terms of waves and wave-interactions. Nature is NOT schizophrenic: Schroedinger's cat IS NOT alive AND dead: As Einstein correctly observed, like any physicist with common sense would have observed: "God does not play dice!"

It is just amazing that the Voodoo of "wave-particle duality" and "complimentarity" has survived for nearly 100 years. It proves that theoretical physicists are not as clever as they are misleading ordinary good folk to think that they are; and in the process squandering billions in taxpayers' money!.

Physics must come out of the dark ages that Bohr, Heisenberg, Born, Dirac etc. have led it into.

antialias_physorg
5 / 5 (3) Nov 23, 2012
Define for me what is the "particle-analogy" that a photon-wave cannot conform to?

Single photon detectors behind a double slit. This is patricularly visible if you do it with electros but you can also do it with photons.

If the photon were just the wave then with every singular photon in the apparatus you'd get a smeared picture all over the receiving screen (because the wave energy would be distributed accross the entire wavefront). However that is not what is observed. Photons arrive at the screen in localized quanta (which is a particle-like behavior)

Better explanation (and experiment) here:
http://sciencedem...pth.html

All the 'particle-like' means is: localized, quantized. non-distributed.
antialias_physorg
5 / 5 (4) Nov 23, 2012
A coherent wave can split into two parts while remaining a single wave so that the two parts remain in intimate with one another. This is NOT possible for "particles".

I agree that this is not possible for particles. But you should try to read before posting replies. No one on earth is saying that photons are particles. No one. (Also no one is saying they are waves. No one)
Photons just exhibit properties/behavior that particles would, too under a certain set of circumstances.

It's a bit like the color blue. Just because my t-shirt is blue does not mean it is the sky. It just exhibits 'sky-like' qualities by having a property that looks the same.

Nature is NOT schizophrenic

No it is not. But nature is also not limited to "It has to be either a wave or a particle and there is no third possibility". I think this is the crucial point you're missing. Waves and particles are MODELS.

The model is not the territory.
johanfprins
1 / 5 (7) Nov 23, 2012
Single photon detectors behind a double slit. etc. etc.


This DOES NOT define "particles" at all. A photon is a coherent wave, and we know that such a wave can split into two entangled parts that remain in intimate contact with one another. Therefore these two entangled components interfere to form a diffracted photon wave-front.

There exists no detector which can detect less light energy than that of a photon. When you thus place two detectors behind the slits, the photon, which consists of two entangled parts, can only be detected by one of these detectors: The photon thus collapses to be detected by one or the other of the two detectors.

If you are stupid you will conclude that the photon has only moved through one of the slits. But it did not! As proved by the fact that when you collapse the two entangled parts they cannot interfere anymore and the diffraction pattern does not form. The latter experimentally proven fact mandates that a photon can ONLY be a wave!!
johanfprins
1 / 5 (7) Nov 23, 2012
If the photon were just the wave then with every singular photon in the apparatus you'd get a smeared picture all over the receiving screen


Why? There is NO detector that can detect part of a photon. The whole wave has to collapse to the size of the detector with which it resonates: This is what Planck discovered.
(because the wave energy would be distributed accross the entire wavefront).
So what? When it resonates with a atomic sized detector it encounters new boundary-conditions and this causes it to change in shape and size: As we KNOW that ALL waves do!
However that is not what is observed. Photons arrive at the screen in localized quanta (which is a particle-like behavior)

It has NOTHING to do with "particle-behavior": It has to do with the atomic size of the detectors within the screen; each of which cannot detect less energy than that of a photon!

johanfprins
1 / 5 (7) Nov 23, 2012
All the 'particle-like' means is: localized, quantized. non-distributed.


The energy of a photon-wave is quantized because there is no light-source that can emit an amount of coherent EM wave-energy that is less than that of a photon. Since the photon is a coherent wave, it changes shape and size when the boundary conditions change.

When the boundary conditions are two slits, it moves through BOTH of them: When the diffracted wave-front reaches the screen, it is distributed across the whole screen: However a photon can only be detected by an atomically-sized detector. Thus it encounters new boundary conditions and morphs in shape and size to fit the size of the detector: Not once does it have to become a "non-wave" that has to be called a "particle".
johanfprins
1 / 5 (8) Nov 23, 2012
I agree that this is not possible for particles. But you should try to read before posting replies. No one on earth is saying that photons are particles. No one. (Also no one is saying they are waves. No one)
Photons just exhibit properties/behavior that particles would, too under a certain set of circumstances.


Like I told you only a schizo-psychopath will define an entity by stating that "it is not this" and it also "is not the opposite". It is totally unnecessary to argue like a lunatic. I am NOT a "nobody" and I am stating that a photon is ONLY a wave; What you consider as "particle" behavior is not different from the purely wave behavior of a photon.

It's a bit like the color blue. Just because my t-shirt is blue does not mean it is the sky. It just exhibits 'sky-like' qualities by having a property that looks the same.
When did your T-shirt act like the sky? This is the most stupid analogy I have ever seen!

johanfprins
1 / 5 (7) Nov 23, 2012
No it is not. But nature is also not limited to "It has to be either a wave or a particle and there is no third possibility".
Which third possibility? Have you got data which can be interpreted as "not-wave" AND also "not-particle"? I am all ears!

I think this is the crucial point you're missing. Waves and particles are MODELS.
I am not missing any crucial point since you are not making any crucial ones. The question is why do you require a "particle-model" when you can model all interactions in nature purely in terms of waves?

Firstly you have been unable to define what a "particle" exactly is, and you have not been able to present any experimental evidence which cannot be modeled purely in terms of waves and their well-known behavior; of morphing in size and shape when the boundary conditions change.

casualjoe
not rated yet Nov 23, 2012
Typing it over and over doesn't make it true. I'm still going with Max Planck, thanks.
Benni
2.3 / 5 (3) Nov 23, 2012
Hey guys........it's a "wavicle". Take it anyway you like.
johanfprins
1 / 5 (4) Nov 23, 2012
Typing it over and over doesn't make it true. I'm still going with Max Planck, thanks.
So do I. Max Planck modeled cavity radiation in terms of stationary waves, each of which fills the whole cavity. He then postulated that the energy of each wave can only increase in terms of quanta of energy. This obviously does NOT mean that light consists of "particles" flitting around within the cavity, but only that the emitters and absorbers within the walls of the cavity cannot emit less energy than a quantum at a time or absorb less energy than a quantum at a time.

When an emitter emits a quantum of light-energy, this energy either inflates to form a single stationary wave that fills the whole cavity, or entangles with an already existing SINGLE stationary wave with the same frequency.

When an absorber absorbs light energy, a quantum of light disentangles from a stationary wave that fills the whole cavity and collapses into the absorber. Straightforward causal wave-physics!
casualjoe
3 / 5 (2) Nov 23, 2012
Fair play johan, i really do want to agree with you and i have often thought along these very lines, all waves would be magical for reasons i don't even know but a wavicle or corpuscle would do fine for communicating our best guesses about what a photon really is.
ValeriaT
1.7 / 5 (6) Nov 23, 2012
The vacuum foam gets more dense, when being shaken in similar way, like the soap foam (you can check this behavior on this Java applet with using of mouse). Therefore every wave spreads in vacuum like the particle at the same moment (a photon, wavicle or quantum wave packet - it doesn't matter, how you call it). Even the wake wave of vacuum formed around particles in motion has a particle character too (deBroglie wave). With compare to soap foam the vacuum foam thickens even when its exposed to static stress (potential energy gains a mass by E=mc^2 equation in the same way, like the kinetic energy). Therefore even the gravity field has its mass density assigned (dark matter field). Literally every gradient is the source of additional energy and mass field.
casualjoe
not rated yet Nov 23, 2012
By communicating i mean communicating without maths.
johanfprins
1 / 5 (5) Nov 24, 2012
Fair play johan, i really do want to agree with you and i have often thought along these very lines, all waves would be magical for reasons i don't even know but a wavicle or corpuscle would do fine for communicating our best guesses about what a photon really is.
I disagree that one should bring in another concept than that a photon is a light-wave moving with momentum p=E/c=(hbar*nu)/c. The wave is a coherent wave which in free space occupies a limited volume: One does not need any other term than "light-wave". To use terms like "particle" or "wavicle" only serve to sow confusion; and this confusion leads to Voodoo concepts like Wheeler's "participating Universe" and "Everett's (a student of Wheeler) Multi-Universes. Wheeler was a fine old gentleman, but just like Dirac and Feynman led realistic physics astray.

The time has come to move out of this chaos: There is no reason to embrace Bohr's superstition that we "cannot understand quantum mechanics".
johanfprins
1 / 5 (6) Nov 24, 2012
By communicating i mean communicating without maths.

That is exactly what I am doing but since it contradicts "wave-particle duality" my manuscripts are rejected without even being sent out for review.

The starting equations are E^2=p^2*c^2 (m(0)*c^2)^2 and E=m*c^2: m(0)*c^2 is the rest-mass energy and m*c^2 the total energy. It is accepted BY ALL that to obtain the concomitant differential wave equation, one must replace THE CORRECT energy term with i*(d/dt) and the momentum term with -i*(del).

For the speed v small, one can derive Schroedinger's equation.

In the case of a photon, m(0)=0, and then you get Maxwell's equation for a light-wave.

For an electron m(0)=m(e)=rest mass of electron. If you first do some simple algebra, the energy that must be replaced with i*(d/dt) is NOT the energy that Dirac used, and therefore the equation that models a moving electron is also a Maxwell equation for EM-energy, but now moving with a speed v less than c.

johanfprins
1 / 5 (5) Nov 24, 2012
Since Dirac used the wrong energy term, his mathematics gave him a nonsensical result: Calculus operators below a square root. Instead of realizing that mathematics is telling him that he is on the wrong track, he forced the mathematics to comply with his autistic reality, by introducing two matrices.

This dubious approach gave him the nonsensical result that the energy of a free electron must be MINUS INFINITY. But this did not deter our autistic savant: He just stated that all the negative energy levels must be filled with electrons.

Unfortunately, this fudging seemed to predict the positron: Utter BS.

By not introducing matrices, and only using standard mathematics, I obtain a Maxwell equation for a freely moving electron: This is what one expects that a unified physics model MUST give. But this also means that Quantum Field Theory must be seriously flawed: It might have to be scrapped.

Modern theoretical physicists are too bigoted to allow publication of this possibility!
johanfprins
2.6 / 5 (5) Nov 24, 2012
@ ValeriaT,

I want to send you a Christmas present: Bath foam and plastic ducks. My grandchildren enjoy foam bubbles and plastic ducks very much, and since you are on the same level when arguing physics, you should also enjoy it.
johanfprins
1 / 5 (3) Nov 24, 2012
@ casualjoe,

Sorry, I now see that you said WITHOUT maths. From just a logical point of view, why would a photon be ANYTHING else than a light-wave? There is no experimental evidence whatsoever that requires this not to be the case!
casualjoe
not rated yet Nov 24, 2012
You can't make a photon without the boundary conditions, they are linked, they are one and the same. Now if you are trying to get to the bottom of what energy actually is, then, you still have to employ particulate descriptions because of the big bang ect..
johanfprins
1 / 5 (4) Nov 24, 2012
You can't make a photon without the boundary conditions, they are linked, they are one and the same.
at least here you are right but you are still missing the point!
Now if you are trying to get to the bottom of what energy actually is, then, you still have to employ particulate descriptions because of the big bang ect..
Wrong! Wrong! Wrong! The "Big Bang" most probably did not involve any "particles" at all. According to Guth, and I believe his reasons are correct, there was a BIG INFLATION. Only a primordial wave can inflate instantaneously, just as an electron-wave around the nucleus of an atom does when it absorbs a photon!

I am going out with friends, but will return on Monday!
casualjoe
not rated yet Nov 24, 2012
Inflation regardless, from a 'point like' origin.
johanfprins
1 / 5 (4) Nov 24, 2012
Inflation regardless, from a 'point like' origin.
If it started from a "point" then as sure as hell the "point" could not have had a tremendously high temperature since temperature requires kinetic-energy and kinetic-energy requires objects moving through space. Thus for our Universe to have inflated from a "point" the energy "within this point" must have been purely potential energy so that the temperature "within this point" must have been T=0.

Thus during inflation, the energy that inflated must have been purely potential energy and the temperature T=0.

Only after the wave-density required the disentanglement of smaller waves which could move through the inflated space did kinetic energy (and thus also time) initiate. The disentangled entities were most probably neutrons. Thus, to reason that the products that we create in our accelerators were present during the "Big Bang" is completely insane.
casualjoe
not rated yet Nov 25, 2012
I think my 'point' still stands as the need for an all encompassing description before we can say for definite the true nature of energy as it is intimately linked with everything else.
johanfprins
1 / 5 (4) Nov 25, 2012
I think my 'point' still stands as the need for an all encompassing description ..


I just cannot understand how people like you reason: Per definition a "particle" CANNOT DIFFRACT. We know that single photons MUST each diffract since sending them consecutively through two slits causes a diffraction pattern to emerge.

We also know that when we change the boundary conditions at the slits the diffraction pattern disappears, as it MUST when you do this for waves.

So how the hell can a single photon be a "particle": Only a totally deranged person will claim that this is the case.

When a radio-wave approaches an antenna, the wave-energy absorbed by the antenna CANNOT have a larger spread in space than allowed by the size of the antenna. So why would an absorbed photon-wave have a larger size as an atomically sized absorber?

You can model ALL physical interactions of photons purely in terms of waves and their interactions. Is this not an "all encompassing description"?
casualjoe
not rated yet Nov 25, 2012
I'd find it pretty difficult to model beta decay using just waves, we have electrons, antineutrinos and photons to deal with. And they're all related somehow, limiting yourself to waves does just that.
johanfprins
1 / 5 (4) Nov 25, 2012
I'd find it pretty difficult to model beta decay using just waves, we have electrons, antineutrinos and photons to deal with. And they're all related somehow, limiting yourself to waves does just that.


Why do you find it difficult? A neutron is a single holistic EM-wave, just like a proton an electron a photon and a neutrino. It can decay by disentangling into a proton-wave, an electron-wave and a anti-neutrino. It is not a bag filled with an electron-"particle", a proton-"particle" and a anti-neutrino "particle". What is your problem? I do not see any problem!

Why must these entities be "particles"? What do you define as a "particle" which makes this undefined concept so important when it comes to beta decay?
casualjoe
5 / 5 (1) Nov 26, 2012
We model charge and the lorentz force using particles, i don't recall you even mentioning charge. And also Planks constant in the photon energy equation suggests a quantum nature at a fundamental level.
rubberman
3.4 / 5 (5) Nov 26, 2012
We model charge and the lorentz force using particles, i don't recall you even mentioning charge. And also Planks constant in the photon energy equation suggests a quantum nature at a fundamental level.


I like the back and forth Johan/Joe. If I may chime in, I think this became far more complicated by the physics world treating mass and energy as as separate entities, but I understand why it happened. We as a race learned to quantify mass and weight long before we knew about energy and wavelength. But once we realized the interchangeability between mass and energy, we failed to unify the terminology and instead, tried harder to separate the concepts. If the human race ever starts trying to simplify things that have become overly complicated....you can "wave" goodbye to particles.
johanfprins
1 / 5 (4) Nov 26, 2012
We model charge and the lorentz force using particles,
Wrong! We model this by using a center-of-charge and a center-of-mass. The fact that a body has a center-of-charge and a center-of-mass does NOT make it a "particle".

It is easy to prove from Einstein's STR that a moving electron is a light-wave modeled by a Maxwell equation, and that this light-wave has a center-of-mass and a center-of-charge.

And also Planks constant in the photon energy equation suggests a quantum nature at a fundamental level.
It only defines the minimum amount of light-energy of a single coherent wave, with that frequency, which can be emitted by a light-source: So Planck's constant is determined by the limitation that, on the atomic scale, a light source which can emit a single coherent wave with less energy cannot exist. This does not demand that all light-waves with a definite frequency can only be photon-waves: A laser beam is a single coherent light-wave with FAR more energy
johanfprins
1 / 5 (4) Nov 26, 2012
I like the back and forth Johan/Joe. If I may chime in, I think this became far more complicated by the physics world treating mass and energy as as separate entities, but I understand why it happened. We as a race learned to quantify mass and weight long before we knew about energy and wavelength. But once we realized the interchangeability between mass and energy, we failed to unify the terminology and instead, tried harder to separate the concepts. If the human race ever starts trying to simplify things that have become overly complicated....you can "wave" goodbye to particles.


Bravo! An excellent summary of the facts.

To this must be added that physics on the quantum scale is, owing to this unification of mass and energy, NOT gauge invariant as is believed, then you can see in what a terrible mess Quantum Field Theory is; as well all physics derived from it; like the BCS model for superconduction.
casualjoe
not rated yet Nov 27, 2012
When people create maths that have the ability to model some aspect of nature, it's beautiful. And Dirac was a cool guy in the grand scheme of things.
TheGhostofOtto1923
4.6 / 5 (11) Nov 27, 2012
But you should try to read before posting replies. No one on earth is saying that photons are particles. No one.
-I think what you mean is everyone instead of no one. Must be a typo.

"A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation, and the force carrier for the electromagnetic force, even when static via virtual photons...The photon is the gauge boson for electromagnetism"

"a gauge boson is a force carrier, a bosonic particle that carries any of the fundamental interactions of nature."
What is lunatic about it? A photon is some entity that has some properties that appear to conform to a wave analogy under some conditions and some other properties that conform to a particle-like analogy under other conditions.
All particles do these things.
Photons can be entangled which is not specifically particle-like nor wave-like behavior
-as well as electrons, molecules as large as buckyballs, and even small diamonds.
johanfprins
1 / 5 (4) Nov 28, 2012
When people create maths that have the ability to model some aspect of nature, it's beautiful.


Any sane physicist will tell you that when he/she develops a model which ends up requiring impossible mathematics, he must have made a mistake in his/her initial assumptions: Garbage in - garbage out.

Only a person with autistic tendencies, like Dirac, will then try and "doctor up" the mathematics, instead of going back and searching for the mistake.

Dirac ended up with calculus operators below a square root: This means that calculus was telling him that he made a mistake.

Instead of being foolhardy, he should have gone back and searched for his mistake: He would then have found that he should first have done some simple high-school algebra on Einstein's equation for the motion of an electron with rest mass m(e) through free space. He would then have found that he should not have replaced the total energy term E=m*c^2 with the calculus operator i(d/dt).
johanfprins
1 / 5 (3) Nov 28, 2012
If he first did the simple algebra required, he would have found that the energy E that must be replaced with the operator i(d/dt) is given by m*v^2=(hbar)*(omega), where v is the speed of the wave. He would then also have found that the momentum of the wave is p=m*v=(hbar)*k, so that k=(omega)/v, which is the relationship that MUST be valid in order to have a coherent wave (moving with speed v) to diffract; as we know that a moving electron does! The wave equation that models such a wave is thus the standard wave equation for a coherent wave, which is a Maxwell-type equation.

This equation for an electron-wave gives different frequencies for the same electron-wave relative to different inertial reference frames, as it MUST since the speed v is different within different IRF's. Dirac's equation DOES NOT model this important aspect.

And Dirac was a cool guy in the grand scheme of things.
He might have been "cool" but his equation is unadulterated mathematical rubbish!
johanfprins
1 / 5 (3) Nov 28, 2012
"A photon is an elementary particle,
It is NOT a "particle", it is a coherent wave with energy (hbar)*(omega) which is modeled by Maxwell's equation for the electric-potential of light.
the quantum of light and all other forms of electromagnetic radiation, and the force carrier for the electromagnetic force, even when static via virtual photons...The photon is the gauge boson for electromagnetism" "a gauge boson is a force carrier, a bosonic particle that carries any of the fundamental interactions of nature."
Gauge bosons have been derived in terms of Dirac's wave equation which is unadulterated trash! If you do physics on the quantum scale correctly, you will find that the energy of any matter-wave is NOT gauge invariant: Thus, to use gauge-invariance to model "gauge-forces" is nonsensical.

Physics on the quantum scale is far simpler than the insane concoctions used in QFT.
eachus
5 / 5 (2) Nov 29, 2012
It is easy to prove from Einstein's STR that a moving electron is...


Stop right there. No scientist would make this statement. Proof in science comes from measurements and observations. If a theory disagrees with experiment, experiment (repeated often thousands of times) wins. THAT is science. Theories that lose out to facts may be retained as useful tools under limited conditions, but that does not make the theory right, just useful. For example, Newtonian mechanics or, for that matter, Einstein's Special Theory of Relativity are only useful in limited conditions. (Einstein's General Theory of Relativity is useful in many more conditions, that's what makes it well, general. ;-)

We know that even Einstein's GTR is inconsistent with QM. Someday there may be a "Theory of everything" with QM and GTR as special cases. Until then, all theories and models, however useful, are wrong. Use them where they work, and test them at the edges to find new physics.
johanfprins
1 / 5 (2) Nov 29, 2012
It is easy to prove from Einstein's STR that a moving electron is...

Stop right there. No scientist would make this statement. Proof in science comes from measurements and observations.


Exactly! That is why Dirac's wave equation fails dismally.

I retraced Dirac's reasoning, and found (when following the SAME ROUTE and REASONING, WITHOUT contriving suspect and unproven mathematics, as Dirac had done) that the differential wave-equation that Dirac should have obtained is Maxwell's equation for EM-energy moving with speed less than the speed of light.

Furthermore, I found that this equation models electron-diffraction for moving electrons, which have different speeds within different inertial reference frames; while Dirac's equation cannot model diffraction within ANY inertial reference frame AT ALL.

Whether my result will stand the test of time is not the issue. The issue is that this result has to date been censored by the editors of 6 journals.

johanfprins
1 / 5 (3) Nov 29, 2012
Proof in science comes from measurements and observations.
AND ALSO FROM LOGICAL DEDUCTIONS FROM EXISTING KNOWLEDGE!

All physicists alive today agree that the relevant wave-equation for an electron must be deduced from Einstein's relativistic equation of motion. This is what Dirac has done; and without ANY measurements and observations his manuscript was published.

This is also exactly what I have done, but in my case my manuscript is rejected without giving ANY justification based on LOGIC, MEASUREMENTS OR OBSERVATIONS.

Thus these criminal editors have decided that new derivations in physics can be rejected without supplying any proof whatsoever that it must be wrong; and without allowing the physics-community at large to look for such proof.

Thus, your unwarranted attack on me should be directed to these criminals!

No-one with any physics-integrity will come in from the sideline, as you have just done, without first checking the facts. You are probably a nincompoop!
Eoprime
3 / 5 (2) Dec 04, 2012
@Johanfprins

I get the impression you are stuck in pre QFT QED physics
and dont have a clue what to do with these concepts because you dont get it.

(I dont understand it in full either but i do not pretend to know better)

You are just spamming the same nonsense over and over again.
johanfprins
1 / 5 (2) Dec 04, 2012
@Johanfprins

I get the impression you are stuck in pre QFT QED physics


I am NOT STUCK in anything; and never has been since this is against the ethos of physics (which you obviously do not understand). After years I just found out through experimental results and mathematically correct derivations from Einstein's Special Theory of Relativity and Maxwell's equations, that QFT QED physics is in essence bollox! This I found without having had to rape mathematics as Dirac has done. Thus after finding this I realized that my long belief in QED and QFT was wrong.

and dont have a clue what to do with these concepts because you dont get it.
BTW I do understand the mathematics and the physics reasoning in these fields. But if you are a real physicist, and you find that a theory (even though you have believed for years that it is correct) has all along been wrong, you are obliged to reject that theory and move on.

johanfprins
1 / 5 (2) Dec 04, 2012
(I dont understand it in full either but i do not pretend to know better)


Then why are you so arrogant to attack and insult me? In contrast to you I do know my physics and have the track record to prove this.

You are just spamming
How do you know this without having studied my arguments based on excellent physics. I am not a hand-waving maniac that hallucinate about ducks and foam, and infinite seas of electrons, and multi-verses and "participating universes". I understand and know what I am doing
the same nonsense over and over again.


Prove in terms of physics-logic that I spout nonsense over and over again! I have derived the correct wave-equation for a freely moving electron, and posted this derivation on this forum. Why do you not start off by showing me where the "nonsense" is in that derivation? I will be pleased if there is a mistake!

So you are the crackpot in this case!!! And a very stupid one at that! Have you ever had any course in physics?

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