Paint the Moon All those Congresspeople who think the web is nothing but a vile pit of pornography need to spend a little time over at the NASA family of websites. There's probably more pages there than all of the internet porn put together.
Here's the latest, of more than a little interest to this board: Warp Drive When?
Actually I once read 20% of the web's traffic was devoted to star trek. As for porn, ever try mistyping a word on the go to line? It's even worst with Yahoo!
I have Kaku's Hyperspace on reserve at the local library... should show up Monday... I'll read it and post ruminations soon after. Also have a book by Bohm (father of hidden variables/pilot wave theory) on hold, as well as a couple more Gribbins, and one that sounds interesting, The Ghost in the Atom, a compilation of interviews with eminent physicists about quantum reality.
If you want you head to really hurt, also try Roger Penrose's The Emperor's New Mind and its sequal, Shadows of the Mind, which are both about machine intelligence, and why Penrose doesn't think it will ever happen (sorry, Data).
Finished the first pass through Hyperspace (pun not intended). It's rather hard to digest, but one of the things that jumped out at me was Kaku's (and apparently Einstein's) interest in the theory of simplicity, which we have discussed here as well...
He also touches on Everett's many-worlds theory. He doesn't discuss Cramer's Transactional interpretation though... I think it was still being developed when he wrote the book...
I'll have to read it a second time more deeply.
Most interesting link in the book: 10/26 dimensional string theory and Ramanujan!
After a bit more reflection...
Kaku is more interested in the hyperspatial aspects of string theory Kaluza/Klein, etc... (I'll have to search the net for Chu references, I haven't seen any, but again, Gribbin was writing after Kaku...).
I contrast this to Gribbin, who (in Schrodinger's Kittens, at least) seemed more interested in the meaning of it all, the search for "reality", an answer to the question "How can it be like that?" that is better than Feynman's "It just is".
I also got a copy of a book by Bohm, which appears to be on Hidden Variables theory (You wouldn't like it Mark, it seems to have lots of math...) and a collection of BBC interviews with noted physicists (Aspect, Bell, Bohm, Periels (sp?), Taylor, Wheeler, et al.) that is called "The Ghost in the Atom", which is also concerned with the reality. Interestingly, Periels (who is obviously a devout Copenhagenist) insists that there is no such thing as reality, while most of the others would prefer to give up (special) relativity in order to preserve reality.
Aspect's experimental verification of Bell's Inequality proved that the world cannot be both "local" and "real". That is, either the speed of light can be exceeded in certain situations, or the world does not exist when we aren't looking at it.
Incidentally, if you haven't read them, Feynman's autobios "Surely You're Joking, Mr. Feynman" and "What Do You Care What Other People Think?" are definitely worth reading. Also "Six Easy Pieces", though they are incredibly outdated. "Six Easy Pieces" are the introductory lectures Feynman gave for non-scientists at CalTech (yes they actually exist!).
(You wouldn't like it Mark, it seems to have lots of math...) You wound me, sir; I have a math minor.
Is Bell's Inequality the proof of EPR paradox? Assuming it is, I'd have to say that what it all implies is that if there is an Ultimate Reality, we'll never find it. Whether it is there or not then leaves the realm of science--if you can't measure it or observe it then Occam's Razor slices it out. In other words, I think the physicists who insist that Aspect's experiment proves there is no underlying reality are off the mark. A Platonic, ideal reality could be there, but science just can't get to it.
A brief philosophical aside. For many people, this is why they say that Revealed Truth, i.e. religion, is in some fashion superior to science, since religion claims to have a hold on Ultimate Reality. But...if you can never, ever hold it, measure it, sense it, detect it with your instruments, or observe it's effects....it might as well not exist as a practical matter. I mean, science is just a way of making experience systematic. And if we can never (objectively) experience it, it might as well not have ever happened.
To go back on topic, I think all the physicists have to give up is the idea that they'll ever directly measure some sort of Ultimate Reality. No need to lose any sleep over it.
But I Could Be Wrong TM
These are some thoughts that came up in another context. I hadn't thought about these ideas for a while, and I'd like to share them with the class.
There is the notion of the subversive nature of scientific inquiry. Sure, there are probably any number of scientists who research what they're told, follow organizational procedures, and function as drones.
But here's my current sig file:"The most exciting phrase to hear in science, the one that heralds the most discoveries, is not 'Eureka!' (I found it!) but 'That's funny....'" -- Isaac Asimov.
Science is the tool of the radical. Many radicals would do well to remember this, and abandon such empty philosophies as postmodernism. The scientific enterprise is designed to undermine our complacent view of ourselves. Existing institutions must fall! Those in control say that we are the center of the universe. Science: no we're not! Those in control say that some are better than others. Science: wrong again. Those in control want to think for you. Science: discover the truth, unhindered by your preconceptions, prejudices, and biases.
As you might imagine, this upsets those in control. Some respond by trying to grapple science to their will (the latest variant of this is patents on the results of gene research). Others do this by attacking science.
I find this notion somewhat ironic, since many people consider science the main tools of repression. I just can't agree with that logic. I blame the state of science education in this country. If more people were exposed to the joy of exploring and understanding the universe at an early age, more people would love science.
Obviously, I'm one of those people. Here's a shocker: mostly because of science fiction. Surely nobody else on this board cares about SF....
In any canon of Great Books, you're not done until you've finished the "Science Fiction and Fantasy" section. Maybe that should be my new sig. . . .
Comments?
Re: Sci-Fi. Gribbin comments that that's how he became interested in science. I believe he says that some of the big names (who exactly, I can't recall) also feel the same way. Now onto other stuff...
After re-reading Hyperspace, I'm impressed with Kaku's math and interpretations. What ruined the book for me is his excursions into the realm of Sci-Fi, in what (I thought) was a "hard science" book.
I have also picked up a copy of Kaku's Beyond Einstein, as well as Six Not-so-easy Pieces (more Feynman lectures). Haven't read them yet... but finished two Gribbin books that I got from the library with Hyperspace ... In Search of the Big Bang (1986) [ISOTBB], and The Search for Superstrings, Symmetry, and the Theory of Everything (1998) [TSFS]. The two are intimately related, as TSFS is an expansion and updating of background quantum material in ISOTBB.
In TSFS, Gribbin gives Kaluza-Klein theory its due (funny, he doesn't mention Chu at all, whose string interpretations he seemed to like in Kittens).
In IOSTBB, he gives the (then) current state of the art on Big-Bang theory, including the historical background. One of the facts that I found interesting there was that while stellar nucleosynthesis is necessary to create elements heavier than helium, there is insufficient helium to begin nucleosynthesis without the Big Bang! (I may have phrased it poorly). This comes from the pioneering work of Gamow and Hoyle in the late '40s.
In TSFS, there is a wonderful appendix, "Recreating the Birth of the Universe in the Lab", where he describes current accelerator status, and how TOE's can be verified/disproved. He also discusses "strange matter". All in all, good reads...
In the pipeline: Constructing Quarks by Andrew Pickering, and the Kaku and Feynman books. Bohm was a bit beyond me, and The Ghost in the Atom was fun, if you're interested in the meaning behind QM rather than just the math...
I know that the Feynman lectures will be good, here's hoping for Pickering and Kaku!
Is Bell's Inequality the proof of EPR paradox?
Not exactly, but the Aspect experiment which violates it proves that the EPR paradox actually occurs, and shows that reality is either non-local or non-real (real in this case means that it exists when nobody is looking). Most theorists (except for hard-core Copenhagenists) would rather give up locality than the objective world... Me too.
Perhaps Special Relativity will have to go...
What ruined the book for me is his excursions into the realm of Sci-Fi, in what (I thought) was a "hard science" book. Like I said, cosmologists and mathematicians like to suppose. And suppose. And suppose. Kaku's other book, Visions, is completely SF (and don't use that other term, or I'll sic the nanobots on you). Or to put it politely, Visions is nothing more than rank futurism.
I think I understand non-local, but could you define it again? Thanks.
non-local: information is passed at greater than the speed of light.
I started Pickering ("Construcing Quarks") and tried to get into it... I really did... He takes a sociological look at the PROCESS of HEP (from '64 to '84), but I just couldn't get into it. I'm sorry, I wish I could... The topic material is interesting, and relevant (esp. given the discussions over on Shet Ma' Mouth)...
Oh, well, maybe I'll try again later... In any case, I still have Kaku and Feynman to go (Feynman should be a joy! If you haven't read the "Feynman Lectures on Physics", of which "Six Easy Pieces" and "Six Not-so-easy Pieces" are a subset, you should!).
Does non-local only refer to information, or matter/energy as well?
Meanwhile, there sits my copy of "Six Easy Pieces," unloved and unread. Hey! I've got writing to do...
The quantum chapter in "Six Easy Pieces" is horrendously dated, but just by reading the book, you get a sense of how brilliant a teacher Feynman was.
"6 Not-so-easy Pieces" is very good. It's most of Feynman's Relativity lectures. So outside of the current String theory stuff, it's still relatively (no pun intended) current. And, of course, Feynman is brilliant again. I really, really, really wish I'd gone to CalTech just so I could have listened to him teach...
Kaku's "Beyond Einstein" is also very good. He stays away from some of those flights of fancy which ruined "Hyperspace" for me. It's a tad drier, but he still writes with a very good style.
In case anyone is interested, my webpage has a bunch of new things on it. http://welcome.to/brianwebber.com
Gribbin (I think in TSFS), gives a really neat derivation of Heisenberg's Uncertainty Principle.
Usually, when the Principle is given, it's in the context of observation. That is, we cannot observe accurately enough to determine both properties of a quantum particle. Gribbin (and I suspect this is the original argument that Heisenberg used - it's so elegant [there's that word again!]), uses the DeBroglie matter wave, Fourier Analysis, Planck's formula for energy, Born's interpretation of the wave function, and the formula for the momentum of a wave front to derive the Principle...
The argument runs thus... The amplitude of a wave at a given point corresponds to the probability of find said partical at that point. We can use Fourier analysis to localize the partical at a given location by building up a wave which is 0 at every point except the interval we are looking at.
HOWEVER..., to do so, we must add in waves of shorter and shorter wavelength (or higher and higher frequncy). Adding these higher frequency waves increases the energy of the wave (E = hn). But the formula for momentum of a wave p = E/c implies that as we increase the localization of the wave (decreasing Dx), we increase its momentum (increasing Dp).
I don't have the exact math on hand, but it's a beautiful argument showing that Heisenberg's Principle is an intrinsic part of the wave/particle duality, whether or not we are observing it (emphasis mine).
Cherenkov radiation is emitted by a charged particle when it exceeds the speed of light in a given medium. It has been observed for electrons travelling in glass and water (IIRC), because the speed of light in those media is slower than in vacuo (therefore travelling faster than light is OK. It's travelling faster than light in a vacuum that's a no-no).
This is related to tachyon theory. How so? Tachyons are hypothetical particles that have an imaginary rest mass, and when all the equations are worked out, must have a speed exceeding that of light. Because by definition a tachyon is never at rest, the imaginary rest mass is not a problem.
Tachyons have mass/energy curves that are the reciprocal of the curves below c. That is, you have to pump energy into a tachyon to slow it down, its mass increases asymptotically as it approaches the speed of light FROM ABOVE.
When a particle emits Cherenkov radiation, it is emitting a photon, and losing energy. Therefore, if tachyons exist, charged tachyons must have infinite speed (warp 10 for you trekkers?), because if they were charged, they'd emit flashes of Cherenkov radiation, lose energy, and speed up. Therefore only neutral tachyons can be "stable".
P.S. How come no comment on my Heisenberg post?
Because you talked right over my head, Scott, for one thing. I'm working on it.
To clarify a bit on the tachyons:
1. Idea One: Mass. You have mass. I have mass. Everyone has mass. It's what makes weight. Look, there's a certain amount of you at any time, right? Now your weight is whatever it is here on Earth, but on about a sixth of that on the moon. But there's still just as much you, it just weighs less. That certain amount of you that doesn't change unless it's physically removed is your mass.
2. Idea Two: Gaining mass as you gain speed. We never notice it at the puny speeds we move at, but as we go faster most of the energy we expend to move goes to moving us--and some is converted to mass and makes us heavy. As objects with mass get closer to the speed of light, that balance changes. Less and less energy goes to moving, and more goes to adding mass.
So normal objects gain mass as they approach the speed of light. You'll never get even as fast as light by just adding energy, because the extra energy doesn't make you faster, it makes you heavier. If you had infinite energy to move, it would make you infinitely heavy and you still wouldn't get to the speed of light, much less beyond.
And what Scott is saying about tachyons is that they work exactly the opposite--they gain mass as they get slower. That's right, slower. The universe is stranger than you can imagine.
Let me try to clear up the Heisenberg thing....
Basically, there is a branch of math called Fourier Analysis, which deals with waves and periodic functions. Fourier proved you can create a wave which matches ANY form by superimposing waves with different frequencies. For example (and it's the one we want), you can create a wave that is 0 at all points except a small interval, thus...
... __________----__________ ...
The only place the wave is non-zero is that small raised area. This is equivalent to localizing the wave function of a particle to that small area.
Now, the way you do that is by taking waves of shorter and shorter wavelength and adding them together. When you have a shorter wavelength, you have a higher frequency (basic physics).
Now then, Planck showed that energy is directly proportional to frequency (E=hn). Treating the particle as a wave, we can use the function for the momentum of a wave (p = E/c). Putting those two together, p=hn/c. But as we localize the particle, we increase its frequency n, so the momentum increases as we localize it.
Thus, the uncertainty principle applies even if we aren't looking at the particle.
oops... looking back, I should probably be referring to uncertainty in momentum, but I hope you get the gist better now...
Let's see if I get this, shall we?
1. The wave/particle duality says that there always exists a wave that is the description of all the possible locations and momentums of a particle. The width of the high point of the particle's wave is a description of the uncertainty of the particle's location. The frequency of the particle's wave is a description of the uncertainty of the particle's momentum.
2. So, particles are also waves. In particular, the particle is the high point of a periodic wave with only one high point. Most waves have many high points; to locate a particle means you are making its high point as small as possible. The smaller the high point, the more exact the particle's location. And vice versa: if the particle is located in space at a particular place, it's high point is very small.
3. But. If the high point is very small, the mathematics says that its frequency is very high.
So, the mathematics guarantees that the more precise the particle's location, the less precise its momentum. And vice versa. Regardless of whether anyone is measuring it at the moment. The uncertainty is not in our measurements. The uncertainty is a fundamental property of the particle.
Assuming a particle is always also a wave, the mathematics of waves dictate that the uncertainty will always be there.
And that's a beautiful math proof there, Scott.
If you're completely lost on the wave/particle duality, check out Hyperspace by Michio Kaku. It has an excellent description of the idea that the wave is a description of the locations and momentums of its particle.
You've just about got it... The only quibble that I have is that the wave function describes the location of the particle as follows:
The square of the amplitude of the wave function at any given point describes the probability of finding the particle at that point.
As I said, I believe that layman's explanation is from The Search For Superstrings, Symmetry, and the Theory of Everything by John Gribbin.
Couple of notes:
Here is Gribbin's home page:
http://epunix.biols.susx.ac.uk/Home/John_Gribbin/
Here is a link to Cramer's 1996 paper on the Transactional Interpretation of QM. If you haven't got the math, don't bother, but here it is anyways...
http://mist.npl.washington.edu/npl/int_rep/tiqm/TI_toc.html
In the '30s Kurt Godel discovered that mathematical logic cannot be both complete. Actually, it was a bit stronger than that. He proved that any "sufficiently powerful" formalism is incomplete.
"All Philosophers are Liars" - ScottN, Puppet Council Philosopher.
The heart of Godel's proof is to construct a sentence in number theory that essentially says the same thing. Godel essentially constructed a mathematical sentence that said "This statment has no proof."
How did he do that? He used a formalism known as "Godel Numbering", wherein statements ABOUT number theory (metastatements) could be expressed as ordinary statments of number theory. Using this formalism, he constructed a statement of number theory, which must be true (because it was constructed properly), but when interpreted as a metatstatement, stated that it had no proof.
This is equivalent to my stating that all philosophers are liars.
The details are very nasty and gnarly. I HIGHLY recommend "Godel, Escher, Bach: an Eternal Golden Braid" by Douglas Hofstaedter as an excellent introduction to this. During the course of this entertaining book, he works up from nothing to the heart of Godel's proof, and assumes no prior knowledge on the part of the reader.
Mwhahaha.... I was a mathematician before I became a software engineer and a quantum/relativity freak...
I hope this makes AllegraG happy...
Oh yeah! It just so happens, I have a copy of "Goedel, Escher, Bach" (etc)
It was recommended to me by one of my high school teachers LOOONGGGG ago...I went out and bought it and honestly I let it intimidate me. I'd forgotten I had it! I'll have a tub session with it soon.
The things that amaze me about math, biology, music, and astrophysics are the patterns that underlie them all. It makes it all seem both profoundly complex, and yet profoundly simple.
How is it that someone (like me) can intuit music so easily, yet plug the numbers in (notes) and it suddenly becomes like a foreign language?
(Running to find the book, tripping over the guitar and knocking over a big gulp on the way)
Just saw it on TV: The real VISOR has been invented ! It's not an eye-implanted chip but a computer-controlled camera with a direct link to the brain. Quite interesting pictures...
I'm a little more rational now... I was in an auto accident last night...
Godel's Incompleteness Theorem is almost a kind of Heisenberg Principle for formal axiomatic systems.
Basically, it states that any formal axiomatic system cannot be both complete and consistent.
Complete = all truths in this formal system can be generated
Consistent = this formal system contains no contradictions.
In other words, it is possible to generate a theorem that states "this theorem has no proof". This is inconsistent. If the system is altered so that such a statement cannot be generated, it is incomplete (all truths cannot be generated).
I hope this makes a bit more sense...
ScottN, I'm glad you're feeling better-I had no idea what you were talking about when you said you were "incoherent". I'm sorry I left my manners at the modem.
Godel's Incompleteness Theorem, as you have described it, registers as very zen-like, which is nice, since I cracked "G,E,&B" this morning and opened straight to "Mumon and Godel".
What a gift. I love ideas that threaten headaches that would take ranger candy to kill.
Here is a link to the "VISOR".
I'll see your Gribbin links, and raise you the fundamental physical constants. I find the weirdest darn things on the Internet.
Run this interesting link about the particle/wave dualism through the Babelfish (German to English).
Here is some of the math for that bit about Uncertainty being an intrinsic property of the wave particle duality.
The frequency of the particle at rest can be determined as follows
E = mc2
E = hn
Thus, hn = mc2, or
n = mc2/h
However, all waves, have a speed of propagation {c}, not to be confused with c, the speed of light (hence the italics), which can be described as c = ln, where l is the wavelength and n is the frequency.
Furthermore, the momentum of a wave is defined as
p = E/c
=> p = hn/ln
=> p = h/l
=> pl = h
Just going to show again, that as we localize the particle by adding smaller and smaller wavelengths, we have to increase the momentum to make it equal to Planck's constant.
Cross-posted from Evolution.vs.Creation...
Physicists at CERN in Switzerland have apparently recreated the "primordial soup" thought to exist immediately after the Big Bang.
http://abcnews.go.com/sections/science/DailyNews/littlebigbang000209.html
Interesting stuff, if you're into HE Physics...
More on that last, direct from CERN, not filtered through the mass media...
http://www.cern.ch/CERN/Announcements/2000/NewStateMatter/story.html
And let me clarify, as this is beginning to get on my nerves (no, not you, Scott). I hate the way they use the term "primordial soup" when describing this experiment. The experiment had nothing to do with abiogenesis--the creation of life--which is often described as "coming out of the primordial soup." Instead it was an apparently successful attempt to recreate the conditions that gave rise to fundamental particles and other aspects of the physical universe as we observe it today.
Read the links for more.
But, you know, this is not the best time to make people any more confused about the difference between Big Bang cosmology and abiogenesis.
Here you go: Happy Valentine's Day from the Mars Global Surveyor! MGS took this beautiful image(142K TIFF image) of a heart-shaped formation on Mars. Part of the NASA Planetary Photojournal.
Bringing a discussion (again) over from Religious Musings...
The Earth's orbit was known to be approximately 93M miles in diameter, and it was noticed that during portions of the Earth's orbit, occultations of Jupiter's moons occurred about 17 minutes late. Some scientist (I forget who, but it might have been Kepler -- help someone?) figured that it might be because light had a finite speed, and had to travel farther at different parts of the Earth's orbit.
Using the best known figure for the radius of the Earth's orbit, he came up with a value of c that was about 160,000 miles per second, which wasn't bad given the crudity of the experimental data.
Kepler's 3 laws of planetary motion:
1: each planet revolves around the sun in an elliptical path, with the sun occupying one of the foci of the ellipse.
2:the straight line joining the sun and a planet
sweeps out equal areas in equal intervals of time.
3:the squares of the planets' orbital periods are proportional to the cubes of the semimajor axes of their orbits.
that's all I'm good for.
That guy was Ole Romer in 1675 (?).
Thank you, Electron!
I'd like to bring back the discussion of "Simplicity".
Over on Religious Musings, the nature of science is (once again? still?) being debated. While it hasn't been mentioned by name recently, Occam's Razor is definitely relevant (which is more likely - the Earth is billions of years old, and the fossil strata are the remains of creatures that lived millions of years ago; or that the Earth was created by a supreme being a few thousand years ago, who laid down those strata to fool us?).
Technically, Occam's Razor states that "Entities shall not be mulitplied without reason", but is usually phrased as "the simplest solution is best".
I believe it was Einstein who once said "Make things as simple as possible, but no simpler." On the first Science Nightstand board, we discussed (briefly) the nature of simplicity. We never got a good answer. The problem is that there are so many ways to define simplicity. So here is another stab at it...
What is the nature of Simplicity? Is it all a matter of perspective? For example, quantum gravity seems complex in four-dimensional space/time, but appears to fall out of 26 dimensional string theory quite naturally.
Is it using the fewest assumptions/axioms? In that case, non-Euclidean geometries (both hyperbolic and spherical) are "simpler" than standard plane geometry, as Euclidean plane geometry relies on the parallel postulate.
Is it a case of "I know it when I see it"? How can we apply that rule?
I believe the following example comes from the comic strip BC. Let's say you're a caveman inventing the wheel. You have created the prototypical square wheel, with a bumpy ride. You figure out that the corners may be the problem. So you "simplify" your wheel, by removing a corner. You have just created the triangular wheel, with a worse ride. But the wheel is "Simpler". You could say a circle is simpler because it has no corners, but one could also say that a circle has infinitely many corners...
Where is the simplicity?
I thought it was also "Fits all the facts" in there.
I could spend K's discussing my views on the nature of science and universal truth, but I'd need to use a spell checker, my 75 mhz computer, and an hour and I ain't doing the first one:-)
Matt, that's a basic goal of science. But take an example: the orbits of the planets. There are two theories, one that says they are all held together by gravity, and another one that says they are held together by gravity pulling on the aliens in their centers. Now say you can't possibly tell these aliens are there. They have no effect on anything. Why are they in your theory? Occam's Razor says they don't need to be there.
But both theories fits all the available data. The point of Occam's Razor is to promote simplicity in theories. The aliens in the center were an unnecessary multiplication of entities.
And you need to use a spell checker anyways.
In case that's a little cryptic, Mitzi Adams (quoted on that page) is the Nitpicker Central Science Consultant. Phil ran science questions past her for several of the books.
Yes, I know, many of you have never bought Phil's books or have even heard of them. Well, get thee hence, people!
Ok, Mark, you explained to Matt the concept of Occam's Razor. Now, does anyone want to have a go at the concept of simplicity (see my earlier post).
I knew what Occam's Razor is. I was just pointing out Scott Left something out.
Well, he also left out that you have to theorize, test, and retheorize, but none of that is specifically part of Occam's Razor.
It sounds like a cheat, but I think scientists are just as enthralled with beauty as anyone else, and I think when they see a beautiful theory they can recognize that. Knowing that is part of the basic parcel of being a scientist, or science-lover such as myself.
For all that I'm all left brained when it comes to science, I think the attempt to find simplicity is ultimately a right-brained thing. It's the same thing that moves the artist and the crafter.
Which is no help at all, I know. And an open invitation for New Agers to abuse the concept of simplicity. But there it is.
Continued from Voyager:Season 1:Parallax.
It is unlikely that a standard event horizon has cracks, because (as far as we know) gravity is uniform.
That said, IMHO, it is highly unlikely that a "traditional" Schwarzchild black hole will actually be found. Why? Because it is the solution for a non-rotating body. How many stellar bodies are there that are non-rotating?
A rotating black hole (I think) is called a Kerr object (note - I don't have my reference materials handy... a Kerr object may be a charged black hole). For convenience (and accuracy), I will call such an object an RBH. An RBH does not have a point singularity. Instead, the object "spreads out" into a toroidal form, and the singularity takes the form of a disk. In this situation, it is possible to approach the singularity along the axis of rotation, without being ripped apart by tidal forces. Charged black holes and charged RBH's are even more interesting. In the case of an RBH, the centrifugal force counteracts some of the gravitational force. In the case of a charged black hole, the electrostatic repulsion does the same thing. In the case of a charged RBH, it's both.
Source: "Faster than Light - Superluminal Loopholes in Physics", by Nick Herbert
Apparently, I was wrongin my opinion about non-rotating black holes. ThinkQuest has this article which comments that black holes eventually stop rotating.
For those who are interested, charged black holes are called Reissner-Nordstrom objects.
Actually, that is just one page in this series of articles about black holes.
Very good quick lay introduction.
CALLING ALL CHEMISTS!! Please help me with an issue that’s really puzzled me since I started re-watching my very old sci-fi videos!!
I’m not sure if the 70s sci-fi series Sapphire and Steel was ever broadcast in the US. In case not (and to remind anyone who has seen it but not for a long time), the voice-over during the opening credits originally went like this:
“All irregularities will be handled by the forces controlling each dimension. Transuranic heavy elements may not be used where there is life. Medium atomic weights are available: gold, lead, copper, jet, diamond, radium, sapphire, silver and steel.”
However, some time towards the end of the show’s run, the voice-over suddenly changed to: “...Medium atomic weights are available: gold, mercury, copper ...” etc. Has anyone got any idea why? I was so curious about this that I typed “atomic weights” into a search engine and got a few periodic tables. Obviously items like jet and diamond weren’t there and neither were either of our two eponymous heroes but as far as I could tell, the atomic weight of both lead and mercury come inside the range of some of the other elements listed in the show.
The character of Lead appeared in the first adventure, but Mercury was never in the show so the change wasn’t for a plot point. Is there a scientific explanation?
Sounds like the Metal Men. ;-)
Heard a lot about Sapphire & Steel, but never saw it.
Jet, I believe, is an organic compound similar to coal.
Diamond is pure Carbon, so it could technically be considered an element.
Sapphire is Aluminum silicate, I believe.
Of course, Steel is an alloy.
Maybe Lead was destroyed & Mercury was it's replacement?
If Lead was destroyed, he died off-screen and his death wasn't mentioned, which is why I was wondering if there was a scientific explanation - whether someone knowledgeable had contacted the TV company that made the series and told them that they really shouldn't have Lead in that list because ...
Incidentally, they don't make children's sci-fi series like this any more - watching some of the adventures at the age of 39, they still scare me half to death!
I'd like to see it sometime, but I don't know if PBS will ever air it.
Jet is a form of coal.
Sapphire, which is any color Corundum, except red, is really an Aluminum oxide, not a silicate, Al2O3 with chromium impurities for color.
Actually Aluminum, Oxygen & Carbon are on the low end of the atomic weight scale, so that medium weight stuff seems to be nonsense.
Coming from the E.vs.C... some random thoughts on relativity.
There are two forms of relativity: Special Relativity (SR) and General Relativity (GR).
SR deal specifically with observers in inertial (non-accelerated) frames of reference. From SR, we get the Lorentz Transform - time dilation/mass increase/lenght contraction.
Note that SR does not specifically prevent Faster than Light (FTL) travel. It maintains that one cannot reach the speed of light from below. As one approaches c from below, all the energy being used to accelerate the observer is converted to mass, increasing the mass. There are two ways to achieve FTL. 1. Start out FTL to begin with, or 2. Get there in a "quantum jump" - you never actually hit c, but jump over the discontinuity. Note that this has nothing to do with Quantum Mechanics.
GR, on the other hand, deals with accelerated frames of references and gravitational fields. Indeed, the Principle of Equivalence for GR specifically states that there is no difference between an accelerated frame of reference or one in a gravitational field. That is, if you put an observer in a closed box, he cannot tell whether he is in motion, accelerating, or stationary in a gravitational field. GR is where we get the expanding universe, black holes, curved space, etc...
And on the lighter side, for those who would like to know about quarks:
One Quark, Two Quark, Red Quark, Blue Quark.
Anyone Ever Wonder If Well Ever Have Computers Like Washuu Has? The Subspace Computers...
You Must Know TENCHI In order To know What I'm talking About ^_^
News from Wolf 359: Ground-based observation of emission lines from the corona of a red-dwarf star
Here's a question. Would a infinite of motion require a infinite amount of energy because of infinite amount of heat dissapsation, or could the energy be a finite amount that just keeps getting passed.
You want to rephrase that in English?
Would an infinte amount of motion require an infinite amount of energy, or could it get by on a finite amount, assuming the Universe has no beginning.
1. It's a null question, since there is no such thing as an infinite amount of motion. Please see Einstein.
2. Assuming it's not a null question, it depends. It would either take an infinite amount of energy (again, see Einstein), or absolutely zero energy (tachyon theory - explained below).
There are theoretical particles called tachyons, which have an imaginary (as in sqrt(-1)) rest mass. These particles ALWAYS travel faster than light, thus the imaginary restmass is irrelevant (as they are never at rest). The key thing is that the energy/time/motion curves for these particles is the inverse of normal particles. It takes an infinite amount of energy to SLOW a tachyon to lightspeed. As tachyons lose energy, they speed up.
Now, there is something called Cherenkov Radiation (also spelled Cerenkov). A charged particle exceeding the speed of light in a given medium emits this radiation. This has been observed (Remember, only the speed of light IN VACUUM is the absolute speed limit).
Let us examine a charged tachyon. It is travelling faster than the speed of light in any medium, so it emits Cherenkov radiation, thereby losing energy and speeding up. Eventually, it loses all energy and travels at (theoretically) infinite speed.
Good enough for you? For ordinary matter, though (1) above applies.
New experiments in quantum teleportation, this time with atoms!
For those who didn't hear it yet: The good old space probe Deep Space 1 did a very succesful flyby with the comet Borelly.
Link
For those webcam specialists out there: The volcano Popocatépetl near Mexico City is doing a nice show again. You can watch it here.
An interview with an iconoclast*.
He claims that the Copenhagen interpretation has been holding back physics, and brings up my favorite theory of reality, Cramer's transactional interpretation.
* iconoclast is my interpretation.
An Online Chat involving Galileo, Newton, Bentley, and Leibniz
The Popocatepetl is active again. See the link above.
(And the CERN people have created more antihydrogen atoms.)
The cold fusion is back! This time scientists from the Oak Ridge National Laboratory used cavitating deuterium bubbles in aceton. We'll see...
Interestingly, the extremely intelligent in scientific matters reporters on CNN (ignores the laughter) didn't call it "cold" fusion, just fusion. They also seemed under the impression that fission and fusion are the same thing.
And not to forget: Pioneer 10 celebrated its 30th anniversary with a successful contact!
Pioneers Homepage and Mission Status.
What a tough little probe.
Pioneer 10, direct ancestor of Kryten's Head #3? 
The fusion discussion gets hotter:
Press Release
Article at Science
Discussion with Critics
Eruption alert! The Popocatepetl is smoking heavily right now. The webcam URL can be found above.
Just in case you didn't know: Again there is a nice looking comet on the sky. Finder chart and pictures of C/2002 C1 (Ikeya-Zhang) are to be found here or here.
I really doubt the veracity of some of these, but they are funny:
Quote:REAL SCIENCE AS SEEN BY STUDENTS
This is a list of comments from test papers, essays,
etc., submitted to science and health teachers by elementary,
junior high, high school, and college students: "It
is truly astonishing what weird science our young scholars
can create under the pressures of time and grades."
The spellings are the original ones. (Transmitted by
Professor Pill-Soon Song, a KASTN editor, from a chemistry
net group called SAFETY@uvmvm.uvm.edu, dated 1/13/96)
1. H2O is hot water, and CO2 is cold water.
2. To collect fumes of sulphur, hold a deacon over
a flame in a test tube.
3. When you smell an oderless gas, it is probably carbon
monoxide.
4. Water is composed of two gins, Oxygin and Hydrogin.
Oxygin is pure gin. Hydrogin is water and gin.
5. A super saturated solution is one that holds more
than it can hold.
6. Liter: A nest of young puppies.
7. Magnet: Something you find crawling all over a dead
cat.
8. Momentum: What you give a person when they are going
away.
9. Vacuum: A large, empty space where the pope lives.
10. Artificial insemination is when the farmer does
it to the cow instead of the bull.
11. The pistol of the flower is its only protection
against insects.
12. A fossil is an extinct animal. The older it is,
the more extinct it is.
13. To remove dust from the eye, pull the eye down over
the nose.
14. For a nosebleed: Put the nose much lower that the
heart until the heart stops.
15. For head colds: use an agonizer to spray the nose
until it drops in your throat.
16. Germinate: To become a naturalized German.
17. The tides are a fight between the Earth and moon.
All water tends towards the moon, because there is no
water on the moon, and nature abhors a vacuum. I forget
where the sun joins in this fight.
18. Blood flows down one leg and up the other.
Some of those also appeared in a book called 'Herrings Go About the Sea in Shawls,' which had originally (in 1931) been titled 'Boners.' The copyright was renewed in 1959, though I don't know if the title changed then or in 1997, when the book was reprinted.
Funny, indeed!
Does anyone here happen to know where I might find some websites that show the classical calculation of the Lifetime of Hydrogen (accelerating charges radiate & assuming the electron orbits the nucleus)?
Also, any websites explaining why Schrödinger abandoned the Klein-Gordon equation for what was to become the Schrödinger equation?
Google is your friend. Try it.
Yeah, Scott, but Ask Jeeves narrows it down drastically, with "helpful links" as a sidebar.
Worldwide side note for today:
Egyptian Pyramid Mysteries to Be Explored Live on TV
It starts in a few minutes. Be mummified!
I saw an awful double pun on a license plate yesterday (and yes it does belong on this board...)
Plate read: MVEM JSU
Plate holder read: This Plate is NP-Complete
Cookie for whoever gets the double pun.
HINT: Said car belonged to a JPL employee.
Well maybe I have been in the basement too long but I am not going to be getting that cookie.
To be honest, I got half of it right away, but took a bit of discussion (and the hint) to figure out the other part of the pun.
It looks suspiciously like an equation, but I do not know which one.
RIP Pioneer 10.
Of course, previous reports of its demise were exaggerated...
Demise nothin'! On to Aldebaran! :-)
I get it. It's the first initial of the planets, in order, starting from the sun and going out.
It is "NP-complete" because those are the letters of the planets that completes the series. I forget what it means, but NP-complete is also a math term.
Yep... NP-Complete is actually a computer science term. It refers to a family of problems that are all currently intractable (the best solutions require exponential time), but if one of them is found to be solvable in polynomial time, they all are.
Definition
Exponential Time: The time required to find a solution for a problem of size N is proportional to the value of eN.
Polynomial Time: The time required to find a solution for a problem of size N is a polynomial function of N (i.e aNx + bNx-1 + ...}
An example of an NP-Complete problem is the "Travelling Salesman" problem. Given a set of cities, and the distance between each city, determine the shortest route the salesman can take so that he visits each city exactly once, and returns to his starting point. (That's the non-mathematical description of the problem).
OK, guys, here's something new for you to chew on...
The big problem with time travel
I've always sort of kept up (in a just-for-fun sort of way - I'm no physicist, believe me! ) with the latest theories on the subject. And it's true that I've never run across this dilemma before.
So basically I'm curious - is it possible that this fella is right, and some of the most brilliant scientific minds of our age are either wrong or overlooking the obvious? Or is there a middle ground?
The problem is, it can't happen that way. Here's why: Should we physically defy Time, we necessarily create a new miniature universe outside of this space/time continuum (an alternate-time-effect). This is essential if we are to retain any sense of continuity; otherwise, we would never know if our time traveling efforts were successful. However, in defying Time, we have also defied the rest of spatial physics--including gravity. The Anomalist
It's late (past my bedtime), so I can't quite put my finger on why, but something about this statement seems naive and simplistic.
However, the realization that the Earth is revolving around the sun, which is moving within the Orion Arm, which in turn is revolving around the core of the Milky Way, which is moving in relationship to the rest of the Local Group, etc. has given serious thinkers of time travel theories pause. There would need to be some mechanism for keeping the time machine on or close to Earth.
Gravity, per se, might not do it (which is the Anomalist's point), but some people theorize that the warping of space in a "gravity well" (which, according to general relativity, is the same thing looked at in a different frame of reference) might. The difference is that gravity, as a force, will be different in different reference frames, as will the strength and extent of the gravity well, but the gravity well itself will still exist.
Interesting article... I'd also wondered how a time machine could find Earth, since Earth is moving through space all the time; nice to see others making that consideration.
I suppose, for science fiction writers out there, one thing must be considered: in order for time travel to work, we'll have already needed to solve the problem of interstellar travel and navigation first. Until then (if ever) time travel can't exist in any form meaningful to the user.
Oh, for the record, I'm not a physicist, either.
ScottN there is a discussion in RM about the nature of G_d which has become bogged down on the questions of infinite regress and whether time has a beginning.
Since clearing up those issues will not resolve the ultimate Ontological questions about G_d, I don't wish to move it here, but if you can put in an appearance to clear up the math and philosophy of ininity, it might help, if not to bring an agreement, at least mutual understanding. Thanks,
Anything with serious mathematical notations i stay away from, but kerriem's link cleared up where all those time travelers went. Until we have interstellar drives cheap enough for a tinkerer to own then no tinkerer can build an effective time machine. An esoteric suicide machine, perhaps.
Re:Last Comment but one
Time machines of that type make Very interesting weapons, though...!
(The British Comic Strip "Strontium Dogs" used "Time Bombs" to get rid of obstacles, adversaries etc. Basically, the target was displaced in time & space, by said weapon, normally into interplanetry space, where they
usually died as a result !)
POP!
From a conversation begun on the DEMG Nits board:
Did you know the theory of aether was never dispoven. (Tryimg to disprove something you can not interact with is tougher than catching nuetrinos.)
I don't know deep physics but at least one person in Analog SF and Fact magazine feels the structure of a vacuum - aether; same difference. Blue Berry
The Michelson-Morley experiment disproved the existence of the aether. NSetzer
Not exactly. The experiment to measure the aether failed. At the time, there was no alternative to Newtonian physics that did not rely on the existence of the aether.
When Special Relativity came along, it was able to explain the failure of the Michelson-Morley experiment and make certain predictions which have been borne out. The aether is irrelevent to Special Relativity. It is not required, but neither is it forbidden. It has been dropped from scientific discussion by the use of Occam's Razor, but if a future theory requires its reactivation, there is no bar to it in any current theory. TomM
The aether is relevant to Special Relativity since it is the preferred reference frame (ie, the frame where the speed of light is always c) and Special Relativity says you can not make that distinction. I suppose one does need to define what one means when one says aether though... NSetzer
In Newtonian physics reference frames are as easily converted one for another as in Special Relativity. More easily, actually, since the math is simpler. The only sense in which the one in which the aether is at rest is "preferred" is that it happens to be the one in which the aether is at rest, and its predicted effects become mathematically trivial.
The fact that the experiment failed and the predicted effects did not occur did not, in itself, invalidate the aether. And as I said earlier, Special Relativity did not disprove the aether, it ignored it.
If I say that something exists and that it will have this specific effect on things and then make the measurement and find that it doesn't have that effect, then is that not disproving it being there (at least in the form I declared it to be)?
Burt Rutan does it again! SpaceShipOne went supersonic during its first powered flight test.
SpaceShipOne is Scaled Composites' (Rutan's) entry in the X-Prize competition.
Is the BMI (Body Mass Index) bunk?
It looks like there may be some serious problems with the Copenhagen Interpretation.
Scott--
I'm not entirely sure I follow this. The sense that I make of it is that with the Afshar experiment we open Schrödinger's box and look at the cat, which should collapse the state, but we still can't tell whether the cat is alive or dead. Is this correct?
He also claims that the many-worlds interpretation is also falsified, Which makes a great big nit out of the entire seventh season Next Gen episode "Parallels."
To be honest, I didn't fully follow it myself. My understanding was that the math for all the interpretations was identical, yet the CI and ManyWorlds interpretation apparently have different probabilities than the Transactional version (which is the theory I tend towards).
It was late, and I'm going to have to re-read this one.
Complicating the entire matter is the added factor of having the cat be bitten by a vampire or zombie before placing it in the box.
Naturally, the Transactional Model was the one I didn't understand, which made the rest of the article tough. Help? Please?
The Transactional model leverages the fact that the most common version of the Schroedinger Wave Equation is incomplete. That is to say, it doesn't take relativity into account.
The relativistic version, called the Dirac Equation (after Paul Dirac, who derived it), actually has *two* solutions for any given set of inputs. One corresponding to a wave function going forward in time (retarded wave), and one for a wave function going backwards in time (advanced wave).
For years, physicists ignored the advanced wave solution, because it didn't seem to make sense. However, in the late 80s/early 90s, Cramer came up with an interpretation that uses advanced waves.
Here's a brief description (standing outside of time).
1. Particle A puts out a retarded "offer" wave, which propagates at c.
2. At some point in the future, particle B accepts the offer wave, and emits an advanced acceptance wave, propagating "backwards" in time at c.
3. The advanced wave cancels out the offer wave to all other particles (by interference), while reinforcing the offer wave sent to particle B (again, by interference).
4. If multiple offers are accepted, one is "selected" randomly.
From particle A's POV, all this happens instantaneously, since the acceptance propagates backwards in time at the same speed that the offer propagates forward.
Yes, this sounds really funky, but in reality, QM has been taking this into account ever since Born's description of the probability function as Y*Y. Why? Because changing the sign of the complex portion of any wave function is equivalent to time reversal. So both solutions to the equation have been (unwittingly) used since the beginning of modern quantum theory.
By the way, the Transactional Interpretation even "solves" the two-slit experiment, including the time delayed variant.
That helps to make a little more sense out of the article. Thanks.
BTW, is it just me, or does it seem odd that the forward wave is "retarded" and the backward one "advanced"?
That's why I never really learned double-entry bookkeeping. Certain aspects of debit and credit seemed backward there as well. (Debits are assets and credits are liabilities.)
At least with electric charge, the explanation is simple. Ben Franklin simply guessed wrong, and by the time we knew it, it was too late to change it.
Time-reverse = Advanced because it happens in advance of the event.
Time-normal = Retarded because it happens after the event.
Thanks for the info, Scott!
I found this robot article interesting.
Going back to ScottN's desire to talk about something simple...
Can someone give me the readers digest version of string theory (or that Biggie Size it version.. Superstring Theory)? I thought that maybe keeping things to the "point" 
was the way to keep it simple but there's this theory out there suggesting that that may not be the case.
I found this interesting.
And I thought a half Klingon half human was interesting...
I think I can show this too. Though, I think my proofs just have more obvious math errors.
http://www.foxnews.com/story/0,2933,196225,00.html
The link isn't working because it has commas in it I think, but if you just copy the news article into your address bar, it will work.
link for you, Torque.
You have dishonored a Klingon ScottN, you will be executed... after you explain to me the backwards in time part of it...
But then I'd have to be executed before I explain it!!!
There is no dishonor in instructing an honorable warrior. Neither to the warrior, nor to the instructor!
Qa'Plagh!
Cloaking Device
http://www.cnn.com/2006/TECH/05/25/invisibility.cloak.ap/index.html
I think Jimmy Hoffa has one of these
So are we pre-emptively in violation of the Treaty of Algeron?
I suspect Iraq used it to hide those weapons of mass destruction...
seriously though, I can't see this ever seeing the the light of day, (no pun intended) Can you imagine the lawsuits that would occur if such a technological device had been created.
Also, would a cloaking cloak be machine washable?
Ah ha! That's where i put my tea cup! Under the invisible blanket!
and now, the invisible bathing suit...
Waits for the inevitable JAL comment about Marina Sirtis
now would a cloaked bathing suit let you see what's underneath or would it make it look like you're a walking head arms and legs with no torso?
Unless it was a two piece in which case it would be Veeery interesting.
http://www.cnn.com/2006/TECH/science/05/26/chicken.egg/index.html
Now it's settled... I'm sure I can sleep better at night now knowing this little trivial factoid.
http://www.cnn.com/2006/WORLD/asiapcf/05/31/third.arm.ap/index.html
3 armed kid born in china...
okay, now to the discussion. First off, this isn't political, this is a scientific discussion...
okay, now to begin..
I seem to recall a lot of headlines over the years of birth defects in china. Does anyone know if this is higher than the rest of the world, for the number of major ones like 3 arms.
Could the atmospheric conditions in china be a cause of these birth defects? I know of difficulty breathing and birth problems where the kid has trouble breathing like the mother but I'm not up on whether or not things like this could also be a result of the poor quality of air in china.
It could be because they have like 1/4th of the world's population it just seems like they have more of them.
Maybe its part of some eugenics program? I mean look at that NBA guy Yao or yow (or whatever) who stands what 7' tall or something?
Or more realistically maybe its more like part of the problems of becoming a world superpower economically, militarily and technologically.
its too bad that the kid can't utilize all three arms... just think of the evolutionary advantage when using a pc. Typing with both hands with simultanious mouse contol!!
Speaking of evolution, can natural evolution still occur for humans? I mean, any variation from the norm, and we attempt to correct it. How does one know that trying to remove one arm is the way things are meant to be? Maybe we should just let nature run its course and see where the abnormalities take us...
It could just be because of rampant pollution in China. Love Canal produced many children born with birth defects.
True part of the problem of such rapid growth and change from an agrarian socialist state to a more open capitalistic market is that human life is not valued as highly as profit and advancement at any cost so pollution controls get shoved to the side resulting in bad things happening.
I guess they are wanting to be like America.
But unless I'm mistaken, China's air quality is worse than any in the USA. So why can't people start blaming China for global warming?
Of course, the USA's air quality did at one time look like China's. In time, China's will get better... but that's after Bird Flu kills half the world! LOL
Exactly they are at about the same point America was during the start of the industrial age in this country and goign through many of the same problems that America is in many ways still going through.
And China is a major part of Global Warming but they are trying to formulate some kind of plan for dealing with their pollution while under King Bush the US has been trying to undermine and unravel our environmental protections in the intrests of profits. But all in all global warming is a global problem caused by irresponsible indutrial practices as well as several other factors......
now now now... no politics...
Sorry politics is involved in science, science is involved in politics at this point and in regards to this issue.
And if you could get Luigi to get his head out of his arse about the stupid "ban" he wants to continue then I'll put the politics in there, unless they are a part of the issue elsewhere.
Otherwise anonymous chill it.
1. Political Musings is for politics.
2. Stop bringing up Luigi's ban all over the Sink. mail chief@nitcentral.com as he is the only one at this point who can arbitrate this issue.
1: Sorry but since I am not allowed or have the liberty to post there thanks to Herr Novi when there is a political component to somethign in science I have to go with it where it is. Sort of the holistic approach to science anyhow as the pollution in china and america is more as the result of the political climate than the technological climte. Pollution could be reduced if it wasnt for the fact that it would reduce the private power company's profits.
2: I have emailed him. Several times. I have gotton NO response whatsoever. Which leads me to believe that either he doesnt care or isnt there or otherwise has abandoned any since of responsibility for this site.
R...
I don't know what your email address is, but keep in mind that many email services have auto spam blocking features and if your message or your email address could be misinterpretted as a spam name, then he might not even see your email.
Please revert to a science discussion instead of complaints about Luigi Novi.
PV: I have never encountered that issue before.
Mark: Sorry.
But I still say some of the science problems in china are part of the political problems of china becoming a "controlled" capitalist country.
http://www.popsci.com/popsci/aviationspace/d1e527098dcda010vgnvcm1000004eecbccdrcrd.html
The question is... will this piloted by someone in a red shirt?
ScottN has to go back to school!
Actually, I've already got a book about VSL theories (Variable Speed of Light).
amazingly, it used to be well known and easy to prove that light was variable. It's only become less well known as better TV's have come along.. Today's TV's just blink on and off.. but years ago... it used to take a good 3 minutes for the light from the TV to appear...
Oh no! The romulans are violating the neutral zone again...
Cloak of Invisibility
Scientists create cloaking device... sort of
(for those people who might not visit the link based on what I wrote about the romulans)
I had the same high school biology teacher as Craig Mello, recent Nobel Prize winner for his work in genetics. Apparently, I didn't get as much out of the class as he did 
you were genetically engineered not to learn anything in that class 
Glow in the Dark Kittens! I'm sure there's a practical application to having your feline glow in the dark...
I just don't know what it is yet...
http://www.foxnews.com/story/0,2933,316592,00.html
Now you'll be able to see where to throw the shoe when you want the thing to shut up while you try to sleep. ;-)