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Discussion in 'Bar' started by 006, May 9, 2011.
'Cosmic rays' as in 'energetic charged particles in space'? They're pretty well-established...
Do you know where cosmic rays come from??
You can just unsubscribe...
It's a pretty well-studied thing. There's a quick summary of the physics at
and an example of a paper in Nature detailing (EDIT: evidence for) how supernova shocks produce them can be found at
with the amount actually reaching Earth depending on other factors (like solar wind conditions, particularly the solar wind magnetic field). This is pretty standard stuff in astrophysics and heliospheric physics courses.
I understand the origin of cosmic rays is well studied but the results are inconclusive. I'll point out a link in the page above to another Nature article "Cosmic-ray theory unravels". Here are a couple quotes
"We're not close to writing the final chapter."
"Low-energy cosmic rays, made mostly of protons, strike Earth continually. They originate within the Milky Way but are seen coming from all directions in the sky because magnetic fields in the Galaxy bend their paths and obscure their original sources. Higher-energy cosmic rays from outside the Galaxy are much less frequent, but are potentially more valuable as astronomical tracers because they barrel into the Galaxy on straighter paths...gleaning clues about these cosmic rays is difficult because of their rarity; on average, fewer than one particle per century strikes a square kilometre of ground. "
Now I am not saying all this shit to disrespect the scientists dedicating their lives to studying the mysteries of the universe. Honestly I have a lot of respect for them, even though I may not sound like it sometimes. But there is a white elephant that I would like to hear scientists talking about more often:
- much of our our historical record is based solely on carbon dating (not all of it, but a lot)
- carbon dating is based on cosmic rays
- we do not know what causes cosmic rays
- therefore we have no solid evidence that in prior millennia cosmic rays reached the earth with the same frequency that they do today (in fact, there is much evidence to the contrary)
- therefore there may be potentially gigantic errors in our historical record.
You know that the one I posted was written *after* that, right? More studying is done, more is known, and so on.
Those things *are* discussed by scientists, but the process is a bit different than you'd imagine. If you read more from scientists, you'd see how (1) is misleading, (2) is not as direct as you'd think, (3) is basically wrong, (4) is exactly the kind of thing that needs a citation (and a more clear statement), and (5) is a huge leap from its already flawed predecessors. Further, the way to figure out what carbon ratio, for example, is a reasonable baseline value doesn't necessarily have to be done as you'd expect. Finally, these things always come with uncertainty intervals that take things like that into account.
Basically, we're not talking about a real elephant in the room - it's more one of those little porcelain sculpture things that doesn't usually get such detailed attention. If you want more scientists talking about it, do science and give reason for talking about it. I think we should nuke space again, and I'll get to mine a lot faster than you'll get to yours because I'm actively doing science. If you're as easily misled into MOND, EU, et cetera as you've indicated above, you're going to need a bit of practice before telling scientists what to look at.
Were Nikola Tesla alive today my guess is that he would be a proponent of the Electric Universe:
THE ETERNAL SOURCE OF ENERGY OF THE UNIVERSE, ORIGIN AND INTENSITY OF COSMIC RAYS by Nikola Tesla
"Rays in every respect similar to the cosmic are produced by my vacuum tubes when operated at pressures of ten millions of volts or more, but even if it were not confirmed by experiment, the theory I advanced in 1897 would afford the simplest and most probable explanation of the phenomena. Is not the universe with its infinite and impenetrable boundary a perfect vacuum tube of dimensions and power inconceivable? Are not its fiery suns electrodes at temperatures far beyond any we can apply in the puny and crude contrivances of our making? Is it not a fact that the suns and stars are under immense electrical pressures transcending any that man can ever produce and is this not equally true of the vacuum in celestial space? Finally, can there be any doubt that cosmic dust and meteoric matter present an infinitude of targets acting as reflectors and transformers of energy? If under ideal working conditions, and with apparatus on a scale beyond the grasp of the human mind, rays of surpassing intensity and penetrative power would not be generated, then, indeed, nature has made an unique exception to its laws."
You're still posting lyrical paragraphs instead of published, reviewed, tested, approved scientific papers ?
If he thought that he'd be wrong. Full stop. He was wrong about 'in every respect similar', because cosmic rays of even higher energies are observed (thousands per m^2 per s for GeV cosmic rays, if I recall correctly and about) reach Earth's surface, and that's a problem in the first third of the first sentence alone - he was working before space physics was really known.
Fermi got the right idea for shock acceleration (see e.g. https://cdsweb.cern.ch/record/1249755/files/p533.pdf for a *non-crackpot* explanation of cosmic ray acceleration mechanisms), so why are you banking on a hypothetical maybe-he'd-have-agreed-with-me-on-something-outside-his-field-of-expertise when you could be reading real science from actual experts? Even better, why aren't you trying to produce publishable results and get them into a peer-reviewed journal like the people who don't swim in the intellectual kiddie pool?
You metarealistic fools.
Anyone around here studied particle physics and/or electrodynamics ?
Anyone studying physics has at least a year's worth of ED under their belt, but I only took one semester of particle physics. Why?
3 years. It's above everything IMO, when you reduce all the science disciplines to their roots.
Just asking, because of the "amount" of stuff being said.
I'm graduating physics, by the way. 4 semesters of electrodynamics (one with relativistic ED, tensorial everything) and one semester of particle physics as well.
Did that class go into QED or any other gauge theories? I'm in space plasma physics, so I don't get to do that stuff more than recreationally...
Yes, it went into QED a bit, but not really to the point of computing those nightmare-like vertices in feynmann diagrams. I actually studied that by myself during a week, because I thought it had been taught in a few classes I had missed, but apparently it didn't. Good luck, anything fluid-related is though stuff.
Huh fluids.. was actually watching this video yesterday and loved how despite old the exemples were cool. Today we'd get CGI animations and whatnot I'm sure and fuck that.