Or maybe not. There are way to many mesons and baryons (hadrons) out there to give them all individual names. The name Y(4140) follows a well established scheme. Y(x) are all upsilon mesons (b-bbar) and x stands for the mass of the given resonance.
"In fact, for most engineering jobs a master's degree is required."
I think that's the OP's point. Is the degree merely required to have the job, or are the things you could only know if you have a masters in Engineering actually the skills required for the tasks performed on the job?
What I replied to was the statement that "Masters and Doctorate programs have nothing to do with the real world of non-academic jobs", which in my world is just plain wrong.
And the reality is that you don't get to use what you learned in college in entry level jobs anyway:-) It all sounds so exciting: high particle physics
A lot of the work done in high energy physics is done by graduate students and post-docs, so yes, entry-level jobs require you do use what you learned in college and they are exciting.
building an OS from scratch, international monetary policies, building a skyscraper. But then you end up fixing typos on web pages, fetching coffee, updating Sarbanes-Oxley paperwork, etc.
For the rest of them you have point, but only a small one.
You know, Masters and Doctorate programs have nothing to do with the "real world" of non-academic jobs. There IS a lot that you don't learn in college, but you are expected to learn it on the job.
This may be true in the U.S. but its not true everywhere else. In many European countries, like my own home Sweden, a master's degree in engineering is not at all uncommon. In fact, for most engineering jobs a master's degree is required.
That doesn't mean it prepares you for the job.
You know, the original post stated that Masters and Doctorate programs have nothing to do with the "real world" of non-academic jobs, which in my world is plain wrong.
Niklask: The Swedish high engineering degree was (until recently) "civilingenjor". CivilingenjÃr is not as extensive as an international master's.
I wouldn't claim that a semester is "extensive". Furthermore, quite a few graduates with a lot more academic credits than what is required.
And my professor and colleagues at my home institution wouldn't agree with you. To them the newly instituted "real" master's program for European nationals isn't much different than the "civilingenjor" (which traditionally have been equated with a master's)
I hardly know anyone who graduated before they began to work.
You must come from a different time or place, because I know nobody who in practice wasn't ready to graduate.
An employer may ask for the moon and the stars but in the end he or she will end up with what the job market can deliver.
Of course, the job market might soon be able to deliver the moon and the stars at low prices.
You know, Masters and Doctorate programs have nothing to do with the "real world" of non-academic jobs. There IS a lot that you don't learn in college, but you are expected to learn it on the job.
This may be true in the U.S. but its not true everywhere else. In many European countries, like my own home Sweden, a master's degree in engineering is not at all uncommon. In fact, for most engineering jobs a master's degree is required.
This is incorrect. However, it works differently than in for example the U.S. In Sweden, a precedent gives the courts guidelines on how to rule given the circumstances. Unfortunately the Wikipedia page describing this is in Swedish only. See Prejudikat
Thanks for the info. One thing that confuses me about that is assuming everything is moving away from the origin of the universe, wouldn't all galaxies always move away from each other.
On large scales yes that is correct...
I recall reading that in some many billions of years, another galaxy will collide with ours. Wouldn't these 2 outcomes be mutually exclusive? Genuinely curious about this.
...but not on local scales, where the gravitational effects are larger. The Mily Way is gravitationally bound in the Local Group (see Wikipedia).
Then why doesn't it agree with their own reasoning?
the band didn't tour and amassed fortunes on record sales.
Nobody is denying that. They were a great rock band.
They had the luxury of not touring when screaming teenagers became annoying.
So the screaming teenagers (and others) were not annoying when they played at Shae stadium? which btw, was the first ever concert in a stadium.
A handful of songs may not have been possible live (Revolution #9 or something)
Now you're just being ignorant. Revolution #9 was released on The White Album, which is much later after they stopped touring. I suggest you take a look at the live recording of "Nowhere man" for example. It sounds nothing like on the studio album. Or "Tomorrow never knows". Please enlighten us how they would have done all the loops etc without modern synthesizers?
but their music was performed live by their contemporaries in the late 1960's.
Some it was yes, but hardly ever those studio tracks that were difficult to play live in a four-piece band.
They could have done it if they enjoyed playing in front of large crowds or needed the extra money.
On the contrary, much of their post-Revolver music was not made for that. You know, they did love playing for large crowds, but got fed up with not being able to hear themselves while playing and thus not being able to improve. Money had little to do with this. Sorry mate.
Want to add a note though. Using The Beatles as an example today is sort of pointless, because we do have all the modern technology available.
I think the Beatles didn't tour after Revolver because they didn't have to, they were able to make a fortune on record sales. That may have been a short-lived era in popular music, but it shouldn't mean the end of creative music.
If you don't really know why they stopped touring, why not say so instead of speculating?
The Beatles got fed up with not hearing themselves play and people coming see them more than listen to them play. And at that time, they didn't have the technology available today to perform many of their later songs. That's why they stopped touring.
Btw. When they played Shae they had one 100 watt amplifier that was made specially for that concert.
.. two options: 1) missing matter 2) incorrect gravitational theory...
How about option 3) electrical discharges as part of powerful magnetic and electric fields?
No, electric charge does not give rise to mass nor interact gravitationally.
(...And fittingly you leave out strong interactions...)
The strong interaction is not DIRECTLY observable to us, because of the fact that it operates over only very short distances.
Again, particle physicists around the world disagree with you, strongly!
At cosmic distances we only directly observe the electric force through photons we intercept.
Again, this is based on your misconception about what produces photons. And again, its electroweak, not electric interaction.
We also observe thorough photons the gravitational (inertial) force in how it governs the motions of heavenly bodies.
Gravitational mass and inertial mass are two different things. Gravitational interaction does not produce photons.
Gravity waves are theorized to exist, but there has so far been no success of detecting or measuring them. Maybe they do exist, but there is no evidence, so far, that they do.
Correct. Interesting how you can accept the hypothesis of gravitational waves, which is a consequence of relativity theory, which you on the other hand have dismissed when saying that there are no black holes and cosmology is wrong.
I think we are not really disagreeing,
Oh yes we are, as is most of the community.
but have a misunderstanding of terms.
No. But you have a misunderstanding of physics as it stands today.
Much of present mainstream cosmology is based on two underlying assumptions. 1) That the observed red-shift of distant objects is due to motion (doppler effect)
Cosmological red shift is not the same as the Doppler effect
and 2) that gravity alone determines the structure and behavior of the large scale universe. I think that modern data does not support these assumptions.
Which is because you do not understand the data.
It is not an understanding of atomic physics that is at issue here.
If those two assumptions are tossed, then all the fairy tale cosmological constructs fall away and well understood electrodynamic processes can adequately explain all the actual data we observe.
Ehm, no!
Food for thought: If there is a pervasive electrical field in space, analogous to the cosmic background radiation, could that explain the incredible energies we measure in cosmic rays?
Ehm, no! Read up on cosmic rays.
If there is an such an electric field of only a few micro-volts per meter, could such a field accelerate a charged particle to the energies we observe? We could never directly measure such a small electric field.
Read up on diffusive shock acceleration.
Space probe data indicates that the energy of the electrons of the solar wind INCREASES slightly as they get further away from the sun.
Reference please.
That means the existence of an accelerating force.
Nothing new.
There may be localized regions in space with vastly greater fields. Could these fields not accelerate electrons and other charged particles to high energies?
Indeed they do. Read up on diffusive shock acceleration and AGN jet physics.
If these high energy electrons then get deflected by the magnetic fields known to exist around stars and planets, would they not also emit plenty of synchrotron radiation
Synchrotron radiation is evidence of relativistic electrons and nothing else.
You do not have to copy-paste Wikipedia articles. Links are just fine. (And btw, I am a particle physicist.)
Still, positrons and electrons are CHARGED objects which are accelerated as they collide. Their charges cancel out and the energy is carried away in ELECTROmagnetic radiation. The electric interaction, NOT gravity nor the strong nuclear force are involved.
Pion decay is NOT due to accelerating charges. Pions decay even at REST.
ANYTIME and ALWAYS
Plain wrong. Ask any particle physicist about direct production of photons in hadronic interactions.
when photons are produced, since they are a phenomenon of the ELECTRIC interaction, they come from a charged object in accelerating motion.
Now you are contradicting yourself again. Photons from neutral pion decays do not come from "accelerating motion".
A neutral pion decays "due to electromagnetic force."
Still has nothing to do with acceleration.
Therefore, electrical charge interaction is the source of the radiation observed. Fictional dark matter need not apply. The same goes for black holes, neutron stars and other esoteric objects theorized to exist in galaxies far, far away, but nowhere around here, closer to home.
You need to check in with modern observations.
All those objects and constructs are modern scientific fairy tales fit for a Star-Wars movie.
Sadly for you, your story is even worse.
The Universe operates by a combination of well tested electrical and gravitational laws.
And fittingly you leave out strong interactions. You are just plain laughable.
Every single actual observation we make, can be adequately explained by their operation.
It is sad that you do not realize this is self-contradictory. Here you say that it can be fully explained, but below you say we have to revise the math.
Present cosmological theories, as beautiful mathematically they may be, are obviously in need of serious revision.
There are, as has been pointed out before to you but you refuse to listen, two options: 1) missing matter 2) incorrect gravitational theory. Option 2 is far less likely because of the extreme accuracy of relativity in other scenarios.
Making the observed data fit a theory is NOT science, but the theory must fit the data.
That was my original point.
Have you ever read about the history of the neutrino? Please do so! And since you obviously do not understand how the scientific model works, I rest my case.
...How do you know that they are the same here and in the far corners of the Universe...
We have observational evidence carried by the radiations from the distant regions of the universe, that rules of electricity and atomic behavior is as it is in your backyard.
(...No. It comes from electric charge..)
Now you are using the same arguments that yo say are wrong in the case of dark matter. Stop contradicting yourself.
Technically you are of course right. The word electron comes from the Greek word for "amber" because they observed that a piece of amber, when rubbed would attract small particles. Any time a charge is accelerated photons are produced.
While true, this is not the ONLY source of high-energy photons, which you claim.
So now tell me where the ELECTRO part of this comes in? Does that not come from electron?
No. It comes from electric charge. Its not just electrons that have electric charge. Geez, read some physics.
What is an electron? Does it have a charge? What happens if that charge moves, specifically is accelerated as it flies out of a decaying atom and runs into something, like another atom or a magnetic field produced by other moving electrons? Has what happens in an atom that decays by this electroweak interaction changed since the 1960s or did it not exist before then? Obviously, electroweak is included in the operation of the ENTIRE universe. The laws of physics operate in the same manner here at home and in the most distant galaxy.
How do you know that they are the same here and in the far corners of the Universe. Short answer is: you don't. Its an assumption we make.
The only inaccurate thing about my post is the last bit, about antimatter. It's a typo. Substitute antimatter with dark matter and the sentence makes sense. I told that the energy spectrum of the electron beams can lead to insight on how they were produced, i.e. the mass of the dark matter particles. And they haven't observed positrons, they're just predicted by some theories, in this case the Kaluza-Klein model.
Yes, I jumped the gun a little too fast. My mistake.
Its interacting clusters of galaxies, not colliding galaxies. And its more than the shape. Its the difference in where weak lensing show concentrations of matter and where X-ray observations show where hot intergalactic gas is.
I concede, it would be more accurate to say clusters of galaxies instead of galaxies, with a negligible loss of communicating power.
But no. They are colliding. You can have numerous types of non-destructive interactions between clusters, none of which is shoving a cluster trough another. If you don't want to call that a collision, I think you'd be very lonely in the astrophysics community.
That is why I used the term interaction, and that is the term most of my co-workers (also astrophysicists and cosmologists) use.
And the x-ray observations are used to determine the distribution of baryonic matter, and thus calculate were the centre of mass should be. The gravitational lensing shows were the actual centre of mass is, and they are not the same.
That is, we have a difference between the actual shape and the one we would have expected from the baryonic matter we see. Now, if it is too much a leap for you associating the centre of mass of a cluster with its shape, I'm sorry. I should have been clearer.
Frankly, it's all in the wikipedia I've linked. So that the interested parties could gather information on how the calculations were made. If I had talked straight about the methods as you did, I doubt many would have understood.
If you by "shape" mean "shape of the mass distribution", then yes I fully agree. But shape is more general in that, and since you were talking about galaxies, it sounded like you were talking about the shape of the galaxies.
Now I understand what you actually meant and I think we could have very meaningful discussions.
My point is not to show off knowledge (I'm very secure of that, thank you), is to distribute some.
Add my point was to add to that information distribution, not to "show off". You are not the only secure one.
Slashdot is a great forum to discuss technical matters, but when it comes to actual science, the general level of knowledge is very low.
On this point I very much agree. The problem with Slashdot is, as I see it, that it is a written forum and because of that it is not the same as a verbal one. In a verbal conversation I would probably have asked "what do you mean by shape?" and the conversation would have progressed from that.
What I find amusing is that the summary is an accurate resume of the article, which is thoroughly inaccurate.
Your post is not accurate either.
The "little evidence" we have is the shape of colliding galaxies,
Its interacting clusters of galaxies, not colliding galaxies. And its more than the shape. Its the difference in where weak lensing show concentrations of matter and where X-ray observations show where hot intergalactic gas is.
of which the most famous is the Bullet Cluster, and gravitational lenses in regions that appear to be free from "normal" matter.
Sometimes the weak lensing maps show lensing where there are very little ordinary luminous matter, but this far from the only case. There are weak lensing maps showing stronger lensing than would be expected from just the luminous matter.
The exciting thing here is that they measured the actual energy spectrum of the beams, which could give insight on what are the particles of antimatter. That, AFAIK, we had no idea until now.
You are very wrong. What they observe is electrons and positrons, neither of which is a new discovery and neither is unknown. The insight that can be gained is how these were produced.
Well actually that is what astronomers did, and it's profoundly absurd.
It is not, and this just shows your ignorance. You should read up on the history of the neutrino. Or read up on the history of atom.
Can you imagine doing that in another scientific discipline?
Biologist: Well I can't account for the development of this organism so I'll just invent another "invisible" type of genetic coding mechanism that no one has ever detected before to explain it!
Again I remind you of the neutrino. Are you saying that neutrinos do not exist?
I'll call it INA (Invisible Nucleic Acid)!
Layperson applying simple logic: Why would you do that? Why not just try and look at all the conventional theories and explicate the organism's development in the confines of those theories and known genetic knowledge instead of creating a new "invisible" NA (nucleic acid) that no one has ever seen or heard of before?
Geneticist: Because that's not interesting enough and it won't get me published frequently enough!
Layperson: Of course
Now here's the situation with Astronomers, they find that galaxies behave in ways they didn't expect, and in ways that look like they have more mass than they should have.
They (we) ARE using conventional physics, i.e. relativity theory and that does not work. Modifying relativity or even newtonian mechanics does not work very well.
If you think this is all about publishability, then you are painstakingly mistaken and should freshen up your physics 1-2-3.
So going by simple logic should they:
A. Make up a new form of matter that has never been observed in the history of science to explain such observations?
Because that has never happened before, right? Physics has not improved with technology. We really do not detect protons and neutrons and electrons, and quarks are just a figment of our imagination. Again, read a little about neutrinos. Just because we cannot detect something does not mean its not there. Thinking so, just shows ignorance.
or
B. Exhaust every conventional explanation first which is limited to known physics principles and known types of matter?
Has been done already. Claiming its either or, just shows how little you know about the field.
Well if you want to do honest science you choose B,
That is so not honest science. Honest science does not discredit any option like you just did.
but if you want to carve out a niche for yourself and get published more frequently even if you're doing bad science and you end up wasting decades of valuable scientific research time on a shaky hypothesis that would get any normal person laughed out of a observatory, you choose A.
Sigh.
Now there are valid hypotheses rooted in conventional physics that explain galaxy motion and other astronomical observations and don't depend on dark energy/dark matter/unicorns/leprechauns, but the astronomical community needs to have the intellectual honesty to examine them closely and thoroughly before they even think of creating alternative types of matter or energy.
They are dismissed because they are not viable theories. They have been examined and scrutinezed and found to be not complete or not working. MOND (modified newtonian dynamics) requires an arbitrary change in the interaction. There is no explanation why, it is just there because it makes things fit nicely. And the results from MOND are not unambiguous. For some galaxies you would have to change the interaction in a slightly different way than other galaxies, to match the rotation curve. Where as with dark matter you get an incredible match with the SAME physics for ALL galaxies. Now which one is more plausible?
Heck, you don't think that we scientists got together one day and said "I know, lets make up some goofy theory and then fudge the data to fit it!" do you?
Actually, it's the other way around. Scientists looked at the data and saw it didn't fit, so they made up some goofy theories that "explained" why their calculations didn't match reality.
You have no idea how the scientific model works, do you? With your reasoning we should never have adopted relativity as the theory describing gravitational interaction and instead stuck with newtonial mechanics, even though more accurate observations of planetary orbits etc showed that newtonian mechanics wasn't correct.
No! My theory isn't WRONG! It's... err... invisible matter that can't be detected in any manner!! Yeah! That's the ticket!
Again, no clue how the scientific model works. BOTH options have been scrutinized. Problems is that relativity works SO WELL in other cases and if we modified it, which could lead to potential problems in those cases where it really works. Occam's razor applies here.
Add to this the strong hints from particle physics that there should be more particles out there.
Can you imagine if you did that in any other field??
Mathematician: And my theory shows conclusively that 2 + 2 is 5!
Person with firm grip on reality: Err... isn't 2 + 2 equal to 4? I can demonstrate with my fingers if you're having trouble visualizing it.
Mathematician: Actually, it IS 5, but the extra is carried away by invisible pixies that cannot be detected!
Bad, bad example. First of, you cannot compare mathematics with physics. Secondly, you can easily construct a mathematically theory in which 2+1=0 and not 3 (this is part of group and ring theory in mathematics). Just because you intuitively are familiar with one theory does not make the other one incorrect. It may not apply to the same problem, but that does not make it incorrect. In physics however, you have a data set, and your model is supposed to describe this. Its very different.
Btw, do you now the history behind the neutrino? It was proposed because the energy spectrum of the electron produced in beta decay was continuous, which it wouldn't be if it was a two-body problem. So it was proposed that there was a third particle involved, the neutrino, that we could not detect but which carried away part of the energy in the decay. Much later, we actually detected neutrinos, and now we detect them on a daily basis. With this hindsight, why is it so implausible that there are neutralinos (the lightest of the supersymmetric particles) out there or some other for of dark matter which we cannot detect with the technology of today?
To me, it seems you are just a skeptic because you do not have a clue about the theories involved.
....Then you start talking about zero point energy in nothing more than a hand-waving fashion that is even less compelling than dark matter.....
The difference between conjectured dark matter in the distant reaches of space and the zero point energy, instead the zero point energy has been experimentally measured right here on Earth. It manifests itself in various ways, one of them is called the Casimir effect. This zero point energy, pervades all of space and affects all atomic processes.
It is really sad that you don't really understand what vacuum energy is, still keep talking about in the most utterly wrong ways.
Anyone who knows a little bit of quantum mechanics knows that vacuum energy is the lowest energy state of any quantum system and that this energy cannot be removed from the system. It has nothing to do with what you are conjecturing in your posts.
(...when we know the interaction is the electroweak interaction...)
This is only one facet of the electric interaction to which all leptons respond to.
Amazing, you keep talking about the "electric" interaction. Ask any particle physicist (and mind you, I am one myself), neutrinos do not carry electric charge and hence are not interacting electromagnetically. And mind you, the electroweak interaction is the more fundamental one, not "electric" interaction.
(...On large scales, gravity is much stronger than the electromagnetic interaction...)
That is flat out wrong unless the matter subject to gravity is strictly neutral, such as it is, fortunately, right around here where we live. The fact is that most matter in the universe is not nicely electrically neutral,
Wrong again. Most matter in the Universe is neutral. Only small fractions are not.
but consists of positive and negative pieces of atoms moving in various paths, as dictated by Galactic, intergalactic or local electric fields. A naked electron or proton existing somewhere between here and the sun is 39 orders of magnitude more sensitive to "feeling" and moving in response to an electric field existing in space than a gravitational field, such as from the Earth are from the sun.
We have abundant evidence of immense magnetic fields associated with galaxies, stars, and planets. The intense magnetic fields observed to exist on the Sun are generated by a correspondingly great electric currents. There is only one way to generate a magnetic field, which is by moving electrical charges (currents). There is also only one way to generate x-rays or gamma rays and that is by means of electricity or electrical atomic activity.
And since every particle physicist worth his name can prove you wrong on this point I rest my case. Mind you, I am in the field and I have had the pleasure to know and work with some of the authorities in the field.
....Quite a bit of the energy release in a nuclear explosion is released as energetic neutrons and neutrinos....
That is true, but even then in the end these are absorbed and end up as electromagnetic energy. Neutrinos may travel quite far before this happens to them, but at some point they to will interact with with an atom somewhere and produce electromagnetic energy.
Sorry, but neutrinos do not interact electromagnetically.
(...Black holes is a consequence of relativity...)
Not at all, in fact relativity prohibits the existence of black holes.
No it does not. Go back and read up on relativity and then solve the equations. Schwarzschild did this already, however.
Even a theoretical black holes cannot be observed by definition since no light or anything else can escape them, according to the theory.
Wrong again. They still have mass and massive objects interact gravitationally. Or are you implying there is no gravity? And add to that Hawking's ideas of black hole radiation. Again, you need to read up more.
According to relativity, a black hole would have to have infinite mass.
Utterly wrong.
(...Take a look at the weak lensing results on the Bullet cluster for example....)
Quite often in science we make an observation and then try to interpret that observation. After a while, the interpretation is equated with the observation itself.
The lensing, in other words the bending of light has been INTERPRETED to be due to a massive object's gravity. We do observe that light is slightly deflected when it passes by the sun or other massive object. That is all we observe and then we speculate about its cause. In 1929 Edwin Hubble observed that starlight shifted in its spectrum toward the red. This has been known ever since as the "red shift". That is all we observe, starlight shifted to the red. This has been INTERPRETED to be caused by motion as in the familiar Doppler effect. There is evidence that the red shift is caused by the steadily increasing zero point energy of space itself.
Provide that evidence. Apparently Occam's razor means nothing to you. You say that dark matter is absurd because there is no evidence. Then you start talking about zero point energy in nothing more than a hand-waving fashion that is even less compelling than dark matter. You basically self-contradicting your arguments.
There is now increasing evidence that the 39 orders of magnitude stronger than gravity electric interaction is responsible for many of the otherwise inexplicable observations coming from modern telescopes and space probes. I do not understand why the incorporation of the electric interaction into the large-scale operation of the universe should be so controversial and greatly opposed by many cosmologists.
Of course you do not understand, because you lack the very basic understanding of physics. The fact that you talk about electric interaction, when we know the interaction is the electroweak interaction is just further proof of this.
On large scales, gravity is much stronger than the electromagnetic interaction.
...Gamma is just energetic photons...
Indeed correct, but are not all photons a manifestation of the electric interaction?
Photons ARE the carriers of electromagnetic interaction. That does not mean, no other interaction can produce photons. You can have direct production of photons in the strong interaction too.
In reactions involving the strong nuclear force all energy produced eventually converted to and released as electromagnetic energy. When an atomic or hydrogen bomb explodes, all sorts of exotic fragments of atoms are flying around. However, in the end all that energy created by the conversion of mass into energy is converted into and dissipated in the form of electromagnetic radiation.
Again, your understanding of basic physics is lacking. Quite a bit of the energy release in a nuclear explosion is released as energetic neutrons and neutrinos.
Nowhere has the force of gravity been observed to be involved in any of this.
Who claims it has to?
Why do cosmologists have to resort to convoluted theories involving gravity and come up with undiscovered and exotic constructs such as dark matter and black holes.
1. Black holes is a consequence of relativity. Relativity has been proven to be very accurate. And, there is plenty of observational evidence for the existence of black holes. Read up on Andrea Ghez from UCLA.
2. While there is yet no direct evidence for dark matter, there are very strong indications. Take a look at the weak lensing results on the Bullet cluster for example.
The well-known principles of modern electrodynamics can interpret the strange observations coming from space probes and modern telescopes. The relatively weak force of gravity is only secondarily involved.
Sorry to say, but this statement is just utterly wrong and just shows your lack of understanding of basic physics.
Slashdot Mirror
Or maybe not. There are way to many mesons and baryons (hadrons) out there to give them all individual names. The name Y(4140) follows a well established scheme. Y(x) are all upsilon mesons (b-bbar) and x stands for the mass of the given resonance.
"In fact, for most engineering jobs a master's degree is required."
I think that's the OP's point. Is the degree merely required to have the job, or are the things you could only know if you have a masters in Engineering actually the skills required for the tasks performed on the job?
What I replied to was the statement that "Masters and Doctorate programs have nothing to do with the real world of non-academic jobs", which in my world is just plain wrong.
And the reality is that you don't get to use what you learned in college in entry level jobs anyway :-) It all sounds so exciting: high particle physics
A lot of the work done in high energy physics is done by graduate students and post-docs, so yes, entry-level jobs require you do use what you learned in college and they are exciting.
building an OS from scratch, international monetary policies, building a skyscraper. But then you end up fixing typos on web pages, fetching coffee, updating Sarbanes-Oxley paperwork, etc.
For the rest of them you have point, but only a small one.
You know, Masters and Doctorate programs have nothing to do with the "real world" of non-academic jobs. There IS a lot that you don't learn in college, but you are expected to learn it on the job.
This may be true in the U.S. but its not true everywhere else. In many European countries, like my own home Sweden, a master's degree in engineering is not at all uncommon. In fact, for most engineering jobs a master's degree is required.
That doesn't mean it prepares you for the job.
You know, the original post stated that Masters and Doctorate programs have nothing to do with the "real world" of non-academic jobs, which in my world is plain wrong.
Niklask: The Swedish high engineering degree was (until recently) "civilingenjor". CivilingenjÃr is not as extensive as an international master's.
I wouldn't claim that a semester is "extensive". Furthermore, quite a few graduates with a lot more academic credits than what is required.
And my professor and colleagues at my home institution wouldn't agree with you. To them the newly instituted "real" master's program for European nationals isn't much different than the "civilingenjor" (which traditionally have been equated with a master's)
I hardly know anyone who graduated before they began to work.
You must come from a different time or place, because I know nobody who in practice wasn't ready to graduate.
An employer may ask for the moon and the stars but in the end he or she will end up with what the job market can deliver.
Of course, the job market might soon be able to deliver the moon and the stars at low prices.
You know, Masters and Doctorate programs have nothing to do with the "real world" of non-academic jobs. There IS a lot that you don't learn in college, but you are expected to learn it on the job.
This may be true in the U.S. but its not true everywhere else. In many European countries, like my own home Sweden, a master's degree in engineering is not at all uncommon. In fact, for most engineering jobs a master's degree is required.
This is incorrect. However, it works differently than in for example the U.S. In Sweden, a precedent gives the courts guidelines on how to rule given the circumstances. Unfortunately the Wikipedia page describing this is in Swedish only. See Prejudikat
Thanks for the info. One thing that confuses me about that is assuming everything is moving away from the origin of the universe, wouldn't all galaxies always move away from each other.
On large scales yes that is correct...
I recall reading that in some many billions of years, another galaxy will collide with ours. Wouldn't these 2 outcomes be mutually exclusive? Genuinely curious about this.
...but not on local scales, where the gravitational effects are larger. The Mily Way is gravitationally bound in the Local Group (see Wikipedia).
No speculation
Then why doesn't it agree with their own reasoning?
the band didn't tour and amassed fortunes on record sales.
Nobody is denying that. They were a great rock band.
They had the luxury of not touring when screaming teenagers became annoying.
So the screaming teenagers (and others) were not annoying when they played at Shae stadium? which btw, was the first ever concert in a stadium.
A handful of songs may not have been possible live (Revolution #9 or something)
Now you're just being ignorant. Revolution #9 was released on The White Album, which is much later after they stopped touring. I suggest you take a look at the live recording of "Nowhere man" for example. It sounds nothing like on the studio album. Or "Tomorrow never knows". Please enlighten us how they would have done all the loops etc without modern synthesizers?
but their music was performed live by their contemporaries in the late 1960's.
Some it was yes, but hardly ever those studio tracks that were difficult to play live in a four-piece band.
They could have done it if they enjoyed playing in front of large crowds or needed the extra money.
On the contrary, much of their post-Revolver music was not made for that. You know, they did love playing for large crowds, but got fed up with not being able to hear themselves while playing and thus not being able to improve. Money had little to do with this. Sorry mate.
Want to add a note though. Using The Beatles as an example today is sort of pointless, because we do have all the modern technology available.
I think the Beatles didn't tour after Revolver because they didn't have to, they were able to make a fortune on record sales. That may have been a short-lived era in popular music, but it shouldn't mean the end of creative music.
If you don't really know why they stopped touring, why not say so instead of speculating?
The Beatles got fed up with not hearing themselves play and people coming see them more than listen to them play. And at that time, they didn't have the technology available today to perform many of their later songs. That's why they stopped touring.
Btw. When they played Shae they had one 100 watt amplifier that was made specially for that concert.
.. two options: 1) missing matter 2) incorrect gravitational theory...
How about option 3) electrical discharges as part of powerful magnetic and electric fields?
No, electric charge does not give rise to mass nor interact gravitationally.
(...And fittingly you leave out strong interactions...)
The strong interaction is not DIRECTLY observable to us, because of the fact that it operates over only very short distances.
Again, particle physicists around the world disagree with you, strongly!
At cosmic distances we only directly observe the electric force through photons we intercept.
Again, this is based on your misconception about what produces photons. And again, its electroweak, not electric interaction.
We also observe thorough photons the gravitational (inertial) force in how it governs the motions of heavenly bodies.
Gravitational mass and inertial mass are two different things. Gravitational interaction does not produce photons.
Gravity waves are theorized to exist, but there has so far been no success of detecting or measuring them. Maybe they do exist, but there is no evidence, so far, that they do.
Correct. Interesting how you can accept the hypothesis of gravitational waves, which is a consequence of relativity theory, which you on the other hand have dismissed when saying that there are no black holes and cosmology is wrong.
I think we are not really disagreeing,
Oh yes we are, as is most of the community.
but have a misunderstanding of terms.
No. But you have a misunderstanding of physics as it stands today.
Much of present mainstream cosmology is based on two underlying assumptions. 1) That the observed red-shift of distant objects is due to motion (doppler effect)
Cosmological red shift is not the same as the Doppler effect
and 2) that gravity alone determines the structure and behavior of the large scale universe. I think that modern data does not support these assumptions.
Which is because you do not understand the data.
It is not an understanding of atomic physics that is at issue here.
If those two assumptions are tossed, then all the fairy tale cosmological constructs fall away and well understood electrodynamic processes can adequately explain all the actual data we observe.
Ehm, no!
Food for thought: If there is a pervasive electrical field in space, analogous to the cosmic background radiation, could that explain the incredible energies we measure in cosmic rays?
Ehm, no! Read up on cosmic rays.
If there is an such an electric field of only a few micro-volts per meter, could such a field accelerate a charged particle to the energies we observe? We could never directly measure such a small electric field.
Read up on diffusive shock acceleration.
Space probe data indicates that the energy of the electrons of the solar wind INCREASES slightly as they get further away from the sun.
Reference please.
That means the existence of an accelerating force.
Nothing new.
There may be localized regions in space with vastly greater fields. Could these fields not accelerate electrons and other charged particles to high energies?
Indeed they do. Read up on diffusive shock acceleration and AGN jet physics.
If these high energy electrons then get deflected by the magnetic fields known to exist around stars and planets, would they not also emit plenty of synchrotron radiation
Synchrotron radiation is evidence of relativistic electrons and nothing else.
Still, positrons and electrons are CHARGED objects which are accelerated as they collide. Their charges cancel out and the energy is carried away in ELECTROmagnetic radiation. The electric interaction, NOT gravity nor the strong nuclear force are involved.
Pion decay is NOT due to accelerating charges. Pions decay even at REST.
ANYTIME and ALWAYS
Plain wrong. Ask any particle physicist about direct production of photons in hadronic interactions.
when photons are produced, since they are a phenomenon of the ELECTRIC interaction, they come from a charged object in accelerating motion.
Now you are contradicting yourself again. Photons from neutral pion decays do not come from "accelerating motion".
A neutral pion decays "due to electromagnetic force."
Still has nothing to do with acceleration.
Therefore, electrical charge interaction is the source of the radiation observed. Fictional dark matter need not apply. The same goes for black holes, neutron stars and other esoteric objects theorized to exist in galaxies far, far away, but nowhere around here, closer to home.
You need to check in with modern observations.
All those objects and constructs are modern scientific fairy tales fit for a Star-Wars movie.
Sadly for you, your story is even worse.
The Universe operates by a combination of well tested electrical and gravitational laws.
And fittingly you leave out strong interactions. You are just plain laughable.
Every single actual observation we make, can be adequately explained by their operation.
It is sad that you do not realize this is self-contradictory. Here you say that it can be fully explained, but below you say we have to revise the math.
Present cosmological theories, as beautiful mathematically they may be, are obviously in need of serious revision.
There are, as has been pointed out before to you but you refuse to listen, two options: 1) missing matter 2) incorrect gravitational theory. Option 2 is far less likely because of the extreme accuracy of relativity in other scenarios.
Making the observed data fit a theory is NOT science, but the theory must fit the data.
That was my original point.
Have you ever read about the history of the neutrino? Please do so! And since you obviously do not understand how the scientific model works, I rest my case.
Direct production in hadronic interactions. Decay of neutral pions. Seriously, you need to catch up with physics.
...How do you know that they are the same here and in the far corners of the Universe...
We have observational evidence carried by the radiations from the distant regions of the universe, that rules of electricity and atomic behavior is as it is in your backyard.
(...No. It comes from electric charge..)
Now you are using the same arguments that yo say are wrong in the case of dark matter. Stop contradicting yourself.
Technically you are of course right. The word electron comes from the Greek word for "amber" because they observed that a piece of amber, when rubbed would attract small particles. Any time a charge is accelerated photons are produced.
While true, this is not the ONLY source of high-energy photons, which you claim.
Same idea for the positron - electron collision - those are clearly not at rest.
Plain wrong. Talk to any particle physicist worth his/her name. The photons created in electron-positron annihilation is not due to moving charges.
...electroweak theory....
So now tell me where the ELECTRO part of this comes in? Does that not come from electron?
No. It comes from electric charge. Its not just electrons that have electric charge. Geez, read some physics.
What is an electron? Does it have a charge? What happens if that charge moves, specifically is accelerated as it flies out of a decaying atom and runs into something, like another atom or a magnetic field produced by other moving electrons? Has what happens in an atom that decays by this electroweak interaction changed since the 1960s or did it not exist before then? Obviously, electroweak is included in the operation of the ENTIRE universe. The laws of physics operate in the same manner here at home and in the most distant galaxy.
How do you know that they are the same here and in the far corners of the Universe. Short answer is: you don't. Its an assumption we make.
The only inaccurate thing about my post is the last bit, about antimatter. It's a typo. Substitute antimatter with dark matter and the sentence makes sense. I told that the energy spectrum of the electron beams can lead to insight on how they were produced, i.e. the mass of the dark matter particles. And they haven't observed positrons, they're just predicted by some theories, in this case the Kaluza-Klein model.
Yes, I jumped the gun a little too fast. My mistake.
Its interacting clusters of galaxies, not colliding galaxies. And its more than the shape. Its the difference in where weak lensing show concentrations of matter and where X-ray observations show where hot intergalactic gas is.
I concede, it would be more accurate to say clusters of galaxies instead of galaxies, with a negligible loss of communicating power.
But no. They are colliding. You can have numerous types of non-destructive interactions between clusters, none of which is shoving a cluster trough another. If you don't want to call that a collision, I think you'd be very lonely in the astrophysics community.
That is why I used the term interaction, and that is the term most of my co-workers (also astrophysicists and cosmologists) use.
And the x-ray observations are used to determine the distribution of baryonic matter, and thus calculate were the centre of mass should be. The gravitational lensing shows were the actual centre of mass is, and they are not the same. That is, we have a difference between the actual shape and the one we would have expected from the baryonic matter we see. Now, if it is too much a leap for you associating the centre of mass of a cluster with its shape, I'm sorry. I should have been clearer.
Frankly, it's all in the wikipedia I've linked. So that the interested parties could gather information on how the calculations were made. If I had talked straight about the methods as you did, I doubt many would have understood.
If you by "shape" mean "shape of the mass distribution", then yes I fully agree. But shape is more general in that, and since you were talking about galaxies, it sounded like you were talking about the shape of the galaxies.
Now I understand what you actually meant and I think we could have very meaningful discussions.
My point is not to show off knowledge (I'm very secure of that, thank you), is to distribute some.
Add my point was to add to that information distribution, not to "show off". You are not the only secure one.
Slashdot is a great forum to discuss technical matters, but when it comes to actual science, the general level of knowledge is very low.
On this point I very much agree. The problem with Slashdot is, as I see it, that it is a written forum and because of that it is not the same as a verbal one. In a verbal conversation I would probably have asked "what do you mean by shape?" and the conversation would have progressed from that.
Not only is he 1960's, he's a troll from the 60's. No need to feed the trolls.
This is "news", not information.
What I find amusing is that the summary is an accurate resume of the article, which is thoroughly inaccurate.
Your post is not accurate either.
The "little evidence" we have is the shape of colliding galaxies,
Its interacting clusters of galaxies, not colliding galaxies. And its more than the shape. Its the difference in where weak lensing show concentrations of matter and where X-ray observations show where hot intergalactic gas is.
of which the most famous is the Bullet Cluster, and gravitational lenses in regions that appear to be free from "normal" matter.
Sometimes the weak lensing maps show lensing where there are very little ordinary luminous matter, but this far from the only case. There are weak lensing maps showing stronger lensing than would be expected from just the luminous matter.
The exciting thing here is that they measured the actual energy spectrum of the beams, which could give insight on what are the particles of antimatter. That, AFAIK, we had no idea until now.
You are very wrong. What they observe is electrons and positrons, neither of which is a new discovery and neither is unknown. The insight that can be gained is how these were produced.
Well actually that is what astronomers did, and it's profoundly absurd.
It is not, and this just shows your ignorance. You should read up on the history of the neutrino. Or read up on the history of atom.
Can you imagine doing that in another scientific discipline?
Biologist: Well I can't account for the development of this organism so I'll just invent another "invisible" type of genetic coding mechanism that no one has ever detected before to explain it!
Again I remind you of the neutrino. Are you saying that neutrinos do not exist?
I'll call it INA (Invisible Nucleic Acid)!
Layperson applying simple logic: Why would you do that? Why not just try and look at all the conventional theories and explicate the organism's development in the confines of those theories and known genetic knowledge instead of creating a new "invisible" NA (nucleic acid) that no one has ever seen or heard of before?
Geneticist: Because that's not interesting enough and it won't get me published frequently enough!
Layperson: Of course
Now here's the situation with Astronomers, they find that galaxies behave in ways they didn't expect, and in ways that look like they have more mass than they should have.
They (we) ARE using conventional physics, i.e. relativity theory and that does not work. Modifying relativity or even newtonian mechanics does not work very well.
If you think this is all about publishability, then you are painstakingly mistaken and should freshen up your physics 1-2-3.
So going by simple logic should they:
A. Make up a new form of matter that has never been observed in the history of science to explain such observations?
Because that has never happened before, right? Physics has not improved with technology. We really do not detect protons and neutrons and electrons, and quarks are just a figment of our imagination. Again, read a little about neutrinos. Just because we cannot detect something does not mean its not there. Thinking so, just shows ignorance.
or
B. Exhaust every conventional explanation first which is limited to known physics principles and known types of matter?
Has been done already. Claiming its either or, just shows how little you know about the field.
Well if you want to do honest science you choose B,
That is so not honest science. Honest science does not discredit any option like you just did.
but if you want to carve out a niche for yourself and get published more frequently even if you're doing bad science and you end up wasting decades of valuable scientific research time on a shaky hypothesis that would get any normal person laughed out of a observatory, you choose A.
Sigh.
Now there are valid hypotheses rooted in conventional physics that explain galaxy motion and other astronomical observations and don't depend on dark energy/dark matter/unicorns/leprechauns, but the astronomical community needs to have the intellectual honesty to examine them closely and thoroughly before they even think of creating alternative types of matter or energy.
They are dismissed because they are not viable theories. They have been examined and scrutinezed and found to be not complete or not working. MOND (modified newtonian dynamics) requires an arbitrary change in the interaction. There is no explanation why, it is just there because it makes things fit nicely. And the results from MOND are not unambiguous. For some galaxies you would have to change the interaction in a slightly different way than other galaxies, to match the rotation curve. Where as with dark matter you get an incredible match with the SAME physics for ALL galaxies. Now which one is more plausible?
Actually, it's the other way around. Scientists looked at the data and saw it didn't fit, so they made up some goofy theories that "explained" why their calculations didn't match reality.
You have no idea how the scientific model works, do you? With your reasoning we should never have adopted relativity as the theory describing gravitational interaction and instead stuck with newtonial mechanics, even though more accurate observations of planetary orbits etc showed that newtonian mechanics wasn't correct.
No! My theory isn't WRONG! It's ... err... invisible matter that can't be detected in any manner!! Yeah! That's the ticket!
Again, no clue how the scientific model works. BOTH options have been scrutinized. Problems is that relativity works SO WELL in other cases and if we modified it, which could lead to potential problems in those cases where it really works. Occam's razor applies here.
Add to this the strong hints from particle physics that there should be more particles out there.
Can you imagine if you did that in any other field??
Mathematician: And my theory shows conclusively that 2 + 2 is 5!
Person with firm grip on reality: Err... isn't 2 + 2 equal to 4? I can demonstrate with my fingers if you're having trouble visualizing it.
Mathematician: Actually, it IS 5, but the extra is carried away by invisible pixies that cannot be detected!
Bad, bad example. First of, you cannot compare mathematics with physics. Secondly, you can easily construct a mathematically theory in which 2+1=0 and not 3 (this is part of group and ring theory in mathematics). Just because you intuitively are familiar with one theory does not make the other one incorrect. It may not apply to the same problem, but that does not make it incorrect. In physics however, you have a data set, and your model is supposed to describe this. Its very different.
Btw, do you now the history behind the neutrino? It was proposed because the energy spectrum of the electron produced in beta decay was continuous, which it wouldn't be if it was a two-body problem. So it was proposed that there was a third particle involved, the neutrino, that we could not detect but which carried away part of the energy in the decay. Much later, we actually detected neutrinos, and now we detect them on a daily basis. With this hindsight, why is it so implausible that there are neutralinos (the lightest of the supersymmetric particles) out there or some other for of dark matter which we cannot detect with the technology of today?
To me, it seems you are just a skeptic because you do not have a clue about the theories involved.
Yes, you are right. I realized that last night...
....Then you start talking about zero point energy in nothing more than a hand-waving fashion that is even less compelling than dark matter.....
The difference between conjectured dark matter in the distant reaches of space and the zero point energy, instead the zero point energy has been experimentally measured right here on Earth. It manifests itself in various ways, one of them is called the Casimir effect. This zero point energy, pervades all of space and affects all atomic processes.
It is really sad that you don't really understand what vacuum energy is, still keep talking about in the most utterly wrong ways. Anyone who knows a little bit of quantum mechanics knows that vacuum energy is the lowest energy state of any quantum system and that this energy cannot be removed from the system. It has nothing to do with what you are conjecturing in your posts.
(...when we know the interaction is the electroweak interaction...)
This is only one facet of the electric interaction to which all leptons respond to.
Amazing, you keep talking about the "electric" interaction. Ask any particle physicist (and mind you, I am one myself), neutrinos do not carry electric charge and hence are not interacting electromagnetically. And mind you, the electroweak interaction is the more fundamental one, not "electric" interaction.
(...On large scales, gravity is much stronger than the electromagnetic interaction...)
That is flat out wrong unless the matter subject to gravity is strictly neutral, such as it is, fortunately, right around here where we live. The fact is that most matter in the universe is not nicely electrically neutral,
Wrong again. Most matter in the Universe is neutral. Only small fractions are not.
but consists of positive and negative pieces of atoms moving in various paths, as dictated by Galactic, intergalactic or local electric fields. A naked electron or proton existing somewhere between here and the sun is 39 orders of magnitude more sensitive to "feeling" and moving in response to an electric field existing in space than a gravitational field, such as from the Earth are from the sun.
We have abundant evidence of immense magnetic fields associated with galaxies, stars, and planets. The intense magnetic fields observed to exist on the Sun are generated by a correspondingly great electric currents. There is only one way to generate a magnetic field, which is by moving electrical charges (currents). There is also only one way to generate x-rays or gamma rays and that is by means of electricity or electrical atomic activity.
And since every particle physicist worth his name can prove you wrong on this point I rest my case. Mind you, I am in the field and I have had the pleasure to know and work with some of the authorities in the field.
....Quite a bit of the energy release in a nuclear explosion is released as energetic neutrons and neutrinos....
That is true, but even then in the end these are absorbed and end up as electromagnetic energy. Neutrinos may travel quite far before this happens to them, but at some point they to will interact with with an atom somewhere and produce electromagnetic energy.
Sorry, but neutrinos do not interact electromagnetically.
(...Black holes is a consequence of relativity...)
Not at all, in fact relativity prohibits the existence of black holes.
No it does not. Go back and read up on relativity and then solve the equations. Schwarzschild did this already, however.
Even a theoretical black holes cannot be observed by definition since no light or anything else can escape them, according to the theory.
Wrong again. They still have mass and massive objects interact gravitationally. Or are you implying there is no gravity? And add to that Hawking's ideas of black hole radiation. Again, you need to read up more.
According to relativity, a black hole would have to have infinite mass.
Utterly wrong.
(...Take a look at the weak lensing results on the Bullet cluster for example....)
Quite often in science we make an observation and then try to interpret that observation. After a while, the interpretation is equated with the observation itself.
The lensing, in other words the bending of light has been INTERPRETED to be due to a massive object's gravity. We do observe that light is slightly deflected when it passes by the sun or other massive object. That is all we observe and then we speculate about its cause. In 1929 Edwin Hubble observed that starlight shifted in its spectrum toward the red. This has been known ever since as the "red shift". That is all we observe, starlight shifted to the red. This has been INTERPRETED to be caused by motion as in the familiar Doppler effect. There is evidence that the red shift is caused by the steadily increasing zero point energy of space itself.
Provide that evidence. Apparently Occam's razor means nothing to you. You say that dark matter is absurd because there is no evidence. Then you start talking about zero point energy in nothing more than a hand-waving fashion that is even less compelling than dark matter. You basically self-contradicting your arguments.
There is now increasing evidence that the 39 orders of magnitude stronger than gravity electric interaction is responsible for many of the otherwise inexplicable observations coming from modern telescopes and space probes. I do not understand why the incorporation of the electric interaction into the large-scale operation of the universe should be so controversial and greatly opposed by many cosmologists.
Of course you do not understand, because you lack the very basic understanding of physics. The fact that you talk about electric interaction, when we know the interaction is the electroweak interaction is just further proof of this. On large scales, gravity is much stronger than the electromagnetic interaction.
...Gamma is just energetic photons... Indeed correct, but are not all photons a manifestation of the electric interaction?
Photons ARE the carriers of electromagnetic interaction. That does not mean, no other interaction can produce photons. You can have direct production of photons in the strong interaction too.
In reactions involving the strong nuclear force all energy produced eventually converted to and released as electromagnetic energy. When an atomic or hydrogen bomb explodes, all sorts of exotic fragments of atoms are flying around. However, in the end all that energy created by the conversion of mass into energy is converted into and dissipated in the form of electromagnetic radiation.
Again, your understanding of basic physics is lacking. Quite a bit of the energy release in a nuclear explosion is released as energetic neutrons and neutrinos.
Nowhere has the force of gravity been observed to be involved in any of this.
Who claims it has to?
Why do cosmologists have to resort to convoluted theories involving gravity and come up with undiscovered and exotic constructs such as dark matter and black holes.
1. Black holes is a consequence of relativity. Relativity has been proven to be very accurate. And, there is plenty of observational evidence for the existence of black holes. Read up on Andrea Ghez from UCLA. 2. While there is yet no direct evidence for dark matter, there are very strong indications. Take a look at the weak lensing results on the Bullet cluster for example.
The well-known principles of modern electrodynamics can interpret the strange observations coming from space probes and modern telescopes. The relatively weak force of gravity is only secondarily involved.
Sorry to say, but this statement is just utterly wrong and just shows your lack of understanding of basic physics.