--------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300003 Date: 01/02/98 From: ADAM MAJER Time: 10:50am \/To: MIKE ROSS (Read 4 times) Subj: Galaxy Missing Mass MR>We know the crest of the wave corresponds to the maximum probability for MR>being the location of a photon. If it happens to be 1 million light MR>years then the particle would seem to appear out of nowhere. This is the MR>basis for teleportation: find a way to destroy its anti-particle and one MR>can put a real particle anywhere in the universe. You don't really affect the location of a perticle. Quantum teleportation only involves the particle's characteristics and not mass or energy. ;-) --- FMail 0.92 # SLMR 2.1 # SPACE-TIME.SYS not found. Universe HALTED. * Origin: The Programmer's Oasis on FIDONET! (1:348/203) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300004 Date: 01/02/98 From: ADAM MAJER Time: 10:50am \/To: TIM EDWARDS (Read 4 times) Subj: Galaxy Missing Mass TE>Wha??! Less-see here... When speaking of the continous waves of radio: TE>For any given speed and wavelength, there is a single frequency, for a TE>given speed and frequency, one wavelength, for a given frequency and TE>wavelength, only one speed... There's only one speed for photons (radio waves, X-rays, all that crap) which is c. --- FMail 0.92 # SLMR 2.1 # Backup not found: (A)bort (R)etry (P)anic * Origin: The Programmer's Oasis on FIDONET! (1:348/203) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300005 Date: 01/02/98 From: MIKE ROSS Time: 12:55pm \/To: TIM EDWARDS (Read 4 times) Subj: Re: curved space TIM EDWARDS said the following to LANCE REYNOLDS on the subject of curved space (31 Dec 97 23:24:00) LR> MR> In 1916 Einstein had predicted that a ray of starlight passing LR> MR> near the edge of our Sun would bend a little. The classical LR>Hmmm. As has been explained to me here several times, light is LR>influenced by gravity; why is light bending as it passes a large mass LR>regarded as curved space and not just curved light "beams?" TE> Photons of light don't have mass that would be influenced by a gravity TE> field, so the simplest explanation becomes that it is following a TE> curve in space. Photons have momentum. Momentum is indistinguishable from mass as far as the force of gravitation is concerned. Conversely the photon has its own gravitational field. When both fields combine the photon simply follows the mean path of their interaction. We observe it as curved light beams. --- Blue Wave/DOS v2.30 * Origin: Juxtaposition BBS. Lasalle, Quebec, Canada (1:167/133) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300006 Date: 12/28/97 From: ROY MCNEILL Time: 12:53am \/To: LANCE REYNOLDS (Read 4 times) Subj: subject changes Hi Lance LR> Separate, completely un-related question(s): Why do the folks in this LR> echo seem to loathe changing the subject when the topic is so LR> obviously a new thread of discussion? Is there some rule about about LR> a maximum number of threads in this echo? This is a chronic problem in echomail, and it's because we are all lazy. People who leave for several months and then return complain that the same old subjects are still active. Suggestion: when you reply to a msg, unless your reply agrees exactly with the subject line, Change It. Cheers --- PPoint 1.88 * Origin: Silicon Heaven (3:712/610.16) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300007 Date: 12/29/97 From: ROY MCNEILL Time: 11:55pm \/To: LANCE REYNOLDS (Read 4 times) Subj: Red shift and Quantum The Hi Lance RM> Relativity is *very* strange. LR> And hard on the minds of simple mechanics. LR> I've been taught that time appears to be going faster for the folx LR> that are going slower, when viewed by the folx going faster. Ie, time LR> dilates with increasing speed. So, why wouldn't your mate see your LR> particle last something less than 10 picoseconds? I'll get back to you on this one. I have a reply partly written, but I gotta verify it against some references (old paperbacks in a dusty carton) before I expose it to the carrion feeders here... Cheers --- PPoint 1.88 * Origin: Silicon Heaven (3:712/610.16) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300008 Date: 01/02/98 From: BARTON PAUL LEVENSON Time: 01:35pm \/To: IAN MOOTE (Read 4 times) Subj: Stars: birth to death. BL> Bok globules are small gas clouds linked to star formation. It's BL> pretty much become the consensus that they condense to early stars. BL> I'll see if I can dig up some cites. IM> I know that clouds of gas will tend to condense into objects which are IM> more dense, but if you could come up with some cites I'd appreciate it. IM> TTYL. It's probably a little late but happy New Year. Scanning through notes... Stellar seismology... strange stars... contact binaries... silicon oxide masers in giant stars... globular clusters... exosolar planets... IMF... warp drive... brown dwarfs... hang on, it's in here somewhere. Detached eclipsing binaries... Hubble Constant... apsidal motion... 21-cm radiation... Olbers's Paradox... FU Orionis stars (now we're getting warm)... Can't find it, damn it. Someone published a paper recently confirming that Bok globules had stars forming inside them, and I can't find the cite. Oh, well. I'm sure they will at least be mentioned in Bok, Bart J. and Bok, Priscilla 1981, THE MILKY WAY (5th Ed.). Try that first. Meanwhile, I'll got through my other notebooks. --- Maximus 3.01 * Origin: SoundingBoard, Pittsburgh PA (1:129/26) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300009 Date: 01/02/98 From: BARTON PAUL LEVENSON Time: 01:41pm \/To: LANCE REYNOLDS (Read 4 times) Subj: the beginning IU> bright with the light of the big bang? I hope I could express my LR> Here is what I think. The BB occurs, and the flash of light from that LR> event begins to travel outward, obviously at c, like ripples from a LR> stone dropped into a pond. All of us matter-folks begin to travel LR> outward as well, but only at a fraction of c. The thing is, the Big Bang was an explosion _of_ space-time, not an explosion _in_ space-time. We can detect the EM echo of the Big Bang; it's the cosmic microwave background. It was first detected and identified as what it really was in 1965, by Arno Penzias and Robert Wilson at AT&T. --- Maximus 3.01 * Origin: SoundingBoard, Pittsburgh PA (1:129/26) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300010 Date: 01/02/98 From: BARTON PAUL LEVENSON Time: 01:47pm \/To: W BOSON (Read 4 times) Subj: c WB> Experiment has shown us (the Michelson-Morley experiment for one) that WB> the speed of light in a vacuum does not depend on one's state of WB> relative motion to "space" - one can be standing still, or one can be WB> moving at an arbitrary direction at an arbitrary velocity, and the speed WB> of light will be the same. Note, though, for completeness, that this is not necessarily true in an accelerated frame. Look at a star 1,000 light-years away on the horizon, then turn around. Relative to your frame of reference, the star just moved 3,141+ light-years in a few seconds. The invariance of c is true only for inertial frames of reference. --- Maximus 3.01 * Origin: SoundingBoard, Pittsburgh PA (1:129/26) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300011 Date: 01/01/98 From: GERALD PEARSON Time: 07:59pm \/To: TIM EDWARDS (Read 4 times) Subj: Re: Red shift and energy Hi Tim, Sorry about the long delay answering -- I did a lot of thinking to try to be clear, but I'm afraid I might simply have wound up being long winded. I certainly rambled a lot. Anyhow, I hope this helps. If you have any more questions, please don't hesitate to ask (unless you're afraid that my answer will be too long :-). -- Gerry On 12 Dec 97 23:53:00 TIM EDWARDS wrote about Re: Red shift and energy: GP> The electromagnetic field is composed of photons. TE> OK.. I am comfortable with the electromagnetic _waves_ being TE> photons.. but the wave is made up of magnetic and electrostatic TE> _componenets_... Yes, sort of like 2 sides of the same coin. Let's talk about the components first, and then talk about the waves later. Long before relativity and quantum mechanics, Maxwell "unified" the electric and magnetic fields, and showed that they're really different faces of the same phenomenon. [The 4 "Maxwell equations"] If you change the speed and position of the origin of the coordinate system, a pure electric field now looks like a mix of electric and magnetic fields, and same with a pure magnetic field. In fact, you can take any arbitrary mix of electric and magnetic, and find/calculate a new coordinate system where the field looks pure electric, and find/calculate a _different_ new coordinate system where the field looks pure magnetic. Consider a beam of electrons deflected by a "pure" magnetic field. Some older TV tubes worked this way, using magnetic deflection instead of electric deflection -- at least along one of the perpendicular axes. AFIK, current-generation CRT video monitors & TV tubes use only electric deflection (but I might be wrong here). Anyhow, of the infinite number of different ways to look at this situation, the following 2 are useful for calibrating your "physical intuition" (or broadening your perspective). (1) In the "fixed" laboratory coordinate system, the charged particle moving perpenducular to a magnetic field feels a force perpendicular to both, and accelerates in that direction. This "bends" or "deflects" the electron beam. (2) In the coordinate system centered on one of the electrons and moving with it, the charge is _not_ moving relative to the magnetic field, so there's no "magnetic" force. OTOH, the coordinate transformation causes a transverse _electric_ field to appear. And (surprise of surprises) this electric field is exactly the right direction and strength to produce exactly the same acceleration as was produced by the _magnetic_ force in #1. These are not two different phenomena, but simply two different ways of looking at the same physical situation, and neither way is more "correct" than the other. If you assume that Newton's equations are exactly correct, then things start acting funny when speeds start to approach the ratio of a couple of fundamental electric and magnetic constants -- which just happens to turn out to equal roughly 3.0 x 10^10 cm/sec. Hmmmmmm..... that's about the speed of light. I wonder what the significance of _that_ might be, or is it just an accident?? Nope, it's not an accident. It turns out that Maxwell's equations _also_ predict that oscillating electric _or_ magnetic waves in space cannot exist all by themselves, but will be part of an electromagnetic wave, which will propagate through free space at that formerly-mentioned speed of roughly 3.0 x 10^10 cm/sec. Maxwell's equations are _not_ invarient under a Gallilean transformation. Transformation = change the speed and location of the origin or the coordinate system, and see how the equations change. Gallilean = non-relativistic -- assuming Newton's laws. In other words, Maxwell's equations are INconsistent with Newton's equations of motion. This bothered the hell out of physicists early on, because they "knew" that Newton's equations were "right", so the only possible resolution of this inconsistency was that Maxwell's equations must be "wrong". But try as they might, they could never cook up any experiment in which Maxwell's equations predicted anything which was inconsistent with what was actually observed. This was all resolved earlier this century, after Einstein cooked up relativity, and everyone realized that Maxwell's equations and Einstein's equations _are_ perfectly consistent with one another, and it was Newton's equations which were "wrong". TE> Ummm... I know that the stream of electrons (Cathode Rays) in the TE> monitors we use to read these messages are being swept by magnetic TE> fields, while the O'scopes use electrostatic deflection... The two TE> fields are distinct in properties. But they _are_ intimately related, as Maxwell pointed out. Indeed, they're just two different faces of the same underlying reality of the electromagnetic field. First there was Newton's equations, to describe motion. Next came Maxwells equations to describe the interaction of charges with the electromagnetic field. Then came Einstein's relativistic equations for motion. Then along came Schrodinger and Heisenberg who cooked up non-relativistic quantum mechanics; this generalized/superseeded Newtons's equations. People _knew_ that this theory could not possibly be the final word, because it is not relativistically invarient. Then P.A.M.Dirac cooked up a relativistically-invarient equation for the motion of an electron which is acted on by electric and magnetic fields. The next level of development was quantum electrodynamics (QED -- Richard Feynmann shared the Nobel prize in physics one year for his part in the development of this theory). _All_ of the earlier theories are just special cases of QED. Anyhow, in QED, there is no such thing as an electric or magnetic field which is _not_ built up out of photons. In other words, QED says that if you find that you have _either_ an isolated electric field _or_ an isolated magnetic field, then you're missing something -- your observations must be incomplete -- because you must actually have one or more electromagnetic waves, each made up of one or more photons. Eventually, QED was superseded and contained by the electroweak theory, which in turn was superseded and contained by quantum chromodynamics. So now we "understand" in principle -- both relativistically and quantum mechanically -- the kinetics and interactions of matter/particles and fields/particles involving the electromagnetic force the weak force, and the strong force. So far, no luck with attempts to generalize this to a relativistic quantum theory which includes gravity. GP>Final thing -- what's the color of a photon? Depends on the GP>wavelength. Wavelength can be _anything_ -- from more than TE> No, not the color of "A" photon, the color of _the_ photon, what color TE> is the photon that interacts with a proton? We can see the lines for TE> the electron energy levels in the spectrum. Each spectral line/color TE> has a state transition energy associated with it. Consider the TE> "Hydrogen Alpha Line"... this common line has a distinct identity TE> related to allowed energy states of the Hydrogen Orbital. TE> What color is the photon that caries the orbital binding force? What TE> line in the spectrum is from that photon? The fact that the wavelength can vary widely with exactly _how_ it interacts should come as no surprise. After all, the wavelength of a photons which interact with _electrons_ can vary widely. The _excess_ electrons in the wires of the tank circuit of an electronic oscillator -- or of the excess electrons in a radio antenna -- slosh back & forth at radio frequencies and interact with photons of these frequencies, namely from a few tens of kiloherz to more than a gigaherz, so the wavelength of "the" photon might be anything from maybe 10 kilometers to less than 30 centimeters. In a magnetron tube in a microwave oven, the electrons in a beam are whizzing around in circular paths (perpendicular to a constant magnet field, BTW) at something more than a gigaherz, and emit microwave photons in the GHz+ frequency range. The electron beam in a klystron tube is modulated ("bunched up" by the oscillating electric field in a microwave cavity, reflects from a negative plate, and the "bunched up" beam feeds more microwave energy back into the microwave cavity than it absorbed in the act of getting bunched up. There are many other kinds of microwave oscillators and amplifiers, both vacuum devices and solid state devices, and as a group they span the "microwave" range of frequencies from about one GHz to hundreds of GHz -- for wavelengths ranging from about 30 cm to a few millimeters or less. Now, you can have a dilute gas consisting of a molecule with some electric dipole moment -- one "end" more "+" charged and the other end more "-" charged. As it tumbles (rotates), the dipole can absorb or emit a photon. This photon will be somewhere in the microwave region. In fact, this photon interacts with _both_ the electrons _and_ the nuclei in the molecule. Another molecular motion is the tunneling of the umbrella-shaped ammonia (NH3) molecule -- it oscillates between the more negatively charged N end being to the left ( N H3 ) and to the right ( H3 N ). Again, the photon absorbed or emitted is in the microwave range, and interacts with all of the electrons and all of the nuclei in the ammonia molecule. Then there's molecular vibrations. Anywhere from the far infrared to the visible and even beyond. Again, the photons interact not only with the electrons in the molecule, but also --- Blue Wave v2.12 * Origin: The Sacred Scribe, 608 827-6755 (1:121/45) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F1300012 Date: 01/01/98 From: GERALD PEARSON Time: 07:59pm \/To: TIM EDWARDS (Read 4 times) Subj: 2 Re: Red shift and energy all of the nuclei. One "cartoon" which might help to understand this is a simple view of the diatomic HCl molecule. H+ Cl- hydrogen end of the molecule is + charged and chlorine end is - charged. Imagine the molecular bond as a spring joining the H+ ion and the Cl- ion. The molecular vibration is an "accordian" stretching/contraction of this spring. The vibration can "grab hold" of the electric field because the electric dipole is stronger when the ions are furthest apart, and weaker when they're closer together. (Just like the electric dipole in a radio antenna, except here the distances are constant but the strength of the charges oscillates.) An x-ray tube works like this. A high energy electron beam is shot at a metal target. When the beam smacks into the target, some of the electrons will knock electrons out of the 1s orbitals (K shell) of some of the metal atoms. As _another_ electron "drops down" to fill up the K-shell "hole" in the metal atom, it creates a photon of wavelength which depends on the metal -- a typical wavelength being a few Angstrom units (a few times 0.000000001 millimeter). _Much_ shorter wavelengths (higher frequencies = higher energies) are emitted when a charged _nucleon_ [i.e. a proton] drops from a higher-energy _nuclear_ orbital into a lower-energy orbital. This does not involve electrons at all. Mass spectroscopy is the process of "weighing" molecular [or atomic] ions. With care, it's possible to weigh an ion to an accuracy of better than one part per million. One form of mass spectroscopy involves (1) generating a cloud of + charged molecular ions in a strong static magnetic field, and then (2) shining radio waves on the cloud to see what frequencies are absorbed by the cloud. The resonant frequencies will equal the cyclotron frequencies of the ions. The cyclotron frequency is how many times per second the ions are whipping around in circles because of the magnetic field, and this frequency is directly proportional to the magnetic field strength, directly proportional to the electric charge, and _inversely_ proportional to the mass of the ion. Most ions will have only one electron stripped off of them, so they'll mostly all have the same charge. If the ion happens to be a positively-charged "normal" hydrogen atom, then it'll be a bare proton, and the photon will not be interacting with any electrons at all. --- Blue Wave v2.12 * Origin: The Sacred Scribe, 608 827-6755 (1:121/45)