Cool physics page
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Kevin McFarlane wrote:
I've always thought this was strange from the time I first read about it when I was about 17. The constancy of the speed of light relative to all observers[^]
What never made sense to me (and still doesn't) is why there should be particles (or whatever they are at any given moment) that just happen to move at the speed that is supposed to be "the fastest speed there is". That really Does Not make any sense, so we're still missing something from the equation. And black holes? I've been arguing against their existence for over 25 years -- with Physics professors, not one of whom has managed to prove (even mathematically, with any real conviction) that they do exist. The truth is probably stranger than the fiction they teach in universities, these days -- but it's probably not so blindly stoopid.
Mark Wallace wrote:
I've been arguing against their existence for over 25 years -- with Physics professors, not one of whom has managed to prove (even mathematically, with any real conviction) that they do exist.
:confused: Mathematics is the easy part, just plug the right mass into the Schwarzchild solution of GR and you get a black hole.
This blanket smells like ham
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We can see the effects a black hole has on various stars. If there is no black hole then what is causing the behaviors observed. If there is something there we should be able to "see" it radiate some kind of signal. Or it could be that the object there is a black hole which accounts for the behavior of the system and why we can not detect the object. Also if you don't believe in a black hole then you can not believe in the concept of space-time.
longbowaj wrote:
We can see the effects a black hole has on various stars.
No, we can see the effect of gravity on stars -- at least, we can on the occasions when indeed we can. Ask any astronomer how reliable the calculations are that compensate for the effects of gravity of other (visible and non-visible) objects between the observer and the object observed. Everyone seems to think that astronomy is a dead-on, balls-accurate science, but it's nothing of the kind. Sure, when we "see" (without using the visible spectrum) a bright object, we get a general idea of its composition (which could be completely wrong, of course, because the light that reaches us passes through God-only-knows-what on the way here), but there is no way of knowing for sure even as much as whether the object is, say, 120 billion or 150 billion light years away. So we give it our best (computer-assisted) guess about the millions-to-billions of years old light, and mark it down as fact -- which everyone believes as Gospel, because almost no-one appreciates the problems involved. Best guesses are good enough, though, no matter how hugely incorrect they are, because it's pretty damned doubtful that anyone will prove them wrong in the next several lifetimes, if ever. It's the assumptions that are piled on top of these best (but probably hideously inaccurate) guesses that are laughable. Looking through a telescope at a star is absolutely nothing like looking through a telescope at a nearby mountain, no matter how many "speculative thinkers" want to believe it is.
longbowaj wrote:
Also if you don't believe in a black hole then you can not believe in the concept of space-time.
Oh, absolutely. I know nothing.
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Jim Crafton wrote:
Considering building an FTL drive?
Pre-BSG (the new series) this used to be called a Warp Drive. Post-BSG, it's now an FTL drive. Ah, a pillar of the 60's-70's finally falls in the language of the common man. ;P Marc
I'm gonna have to say Bah on that. Lots of people called it FTL drives, mostly because it doesn't specify the technology used to achieve it. "Spooling up the FTL drive" however is a new and shiny from the new Battlestar Galactica tv series (what guy doesn't like supermodel-nympho-cylons?)
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You're thinking in terms of space and time, not space-time. Instead of thinking of a particle as moving at the speed of light, look at it this way. All particles have the same energy, it's just that some distribute it as mass. If a pasticle has no mass it must, by defenition, move at the speed of light in order to compensate for the lack of mass which would otherwise take up it's energy. A Particle with mass can never actually reach the speed of light because it has mass, and by defenition cannot reach the speed of light without removing from it's mass. ------------------ As for black holes, i too doubt they exist. As gravitational sinks they do of course exist, as has been noted we can see their effects. The reason it is though there may be a singularity is to do with pure maths, not physics at all! A mathematical singularity is something you cannot get away from with the formulas you are using. In the appolo space programme they had issues with Gimbal Lock. This isn't a real issue, it has to do with the method they used for representing orientation and rotation. these days the maths is more refined, and Gimbal Lock has gone away! If you look at black holes in terms of imaginary numbers, the mathematical singularities go away. For proof of the problems with classic black holes, google for black hole evaporation...(thats right, they eventually evaporate away to nothing!!!!)
barney_parker wrote:
You're thinking in terms of space and time, not space-time.
Sorry, but I'm afraid I'm not.
barney_parker wrote:
Instead of thinking of a particle as moving at the speed of light, look at it this way. All particles have the same energy, it's just that some distribute it as mass. If a pasticle has no mass it must, by defenition, move at the speed of light in order to compensate for the lack of mass which would otherwise take up it's energy. A Particle with mass can never actually reach the speed of light because it has mass, and by defenition cannot reach the speed of light without removing from it's mass.
The above is all mathematical conjecture, based on concepts that have not been categorically proven. Statistics is another field that is based largely on mathematical conjecture.
barney_parker wrote:
The reason it is though there may be a singularity is to do with pure maths, not physics at all!
Precisely. The problem is that it's the same kind of mathematical thinking that "proves" an expansive spring will expand in direct proportion to the weight applied to it, all the way to infinity. The imaginary numbers concept does have a lot going for it, but beware of calculations that seem to make perfect sense of something we know so little about.
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Mark Wallace wrote:
I've been arguing against their existence for over 25 years -- with Physics professors, not one of whom has managed to prove (even mathematically, with any real conviction) that they do exist.
:confused: Mathematics is the easy part, just plug the right mass into the Schwarzchild solution of GR and you get a black hole.
This blanket smells like ham
Andy Brummer wrote:
Mathematics is the easy part, just plug the right mass into the Schwarzchild solution of GR and you get a black hole.
Indeed. just dump 300 billion kilos on a four-inch expansive spring that expands precisely one inch per kilo, and it will expand precisely 300 billion inches. Nothing is simpler than wrong mathematics.
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FTL is what it says on the elastic waistband of my boxer briefs. What does that have to do with quantum physics and/or driving? :confused:
Meddle not in the affairs of dragons, For you are crunchy, and good with mustard.
tsdragon wrote:
FTL is what it says on the elastic waistband of my boxer briefs. What does that have to do with quantum physics and/or driving?
I really don't think you want to mention such speeds in the context of your your boxers.
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Interested in Einstein and Relativity? Considering building an FTL drive? Check this out![^] I'm incorporating the changes right now into my Einstein-Crafton quantum condensate drive.
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Andy Brummer wrote:
Mathematics is the easy part, just plug the right mass into the Schwarzchild solution of GR and you get a black hole.
Indeed. just dump 300 billion kilos on a four-inch expansive spring that expands precisely one inch per kilo, and it will expand precisely 300 billion inches. Nothing is simpler than wrong mathematics.
Mark Wallace wrote:
Nothing is simpler than wrong mathematics.
The physics are wrong in your example, but there is no problem with the math.
Mark Wallace wrote:
just dump 300 billion kilos on a four-inch expansive spring that expands precisely one inch per kilo, and it will expand precisely 300 billion inches.
:confused:, garbage in garbage out I guess. Anyway, so you don't believe in GR? Personally, I consider black holes to be likely, but I wouldn't be surprised if they were eventually supplanted by some other phenomenon given how little we understand about quantum gravity. However, there are tons of observations of objects which can only be described by black holes using classical general relativity.
This blanket smells like ham
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Personally, I think Einstein had a great sense of humor and pulled the greatest hoax of all time. We did, fortunately, luck out on the atomic bomb. Lilith
If that's true Dirac and Schrodinger are the real pranksters, fortunately we did luck out on semiconductors. :sigh:
This blanket smells like ham
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Kevin McFarlane wrote:
I've always thought this was strange from the time I first read about it when I was about 17. The constancy of the speed of light relative to all observers[^]
What never made sense to me (and still doesn't) is why there should be particles (or whatever they are at any given moment) that just happen to move at the speed that is supposed to be "the fastest speed there is". That really Does Not make any sense, so we're still missing something from the equation. And black holes? I've been arguing against their existence for over 25 years -- with Physics professors, not one of whom has managed to prove (even mathematically, with any real conviction) that they do exist. The truth is probably stranger than the fiction they teach in universities, these days -- but it's probably not so blindly stoopid.
Mark Wallace wrote:
What never made sense to me (and still doesn't) is why there should be particles (or whatever they are at any given moment) that just happen to move at the speed that is supposed to be "the fastest speed there is".
What's even more surprising is that there are particles that don't move at that speed.
Mark Wallace wrote:
The truth is probably stranger than the fiction they teach in universities, these days -- but it's probably not so blindly stoopid.
It sure seems to do a good enough job. We definitely have some pretty cool technology based on the fiction that they teach. :|
This blanket smells like ham
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barney_parker wrote:
You're thinking in terms of space and time, not space-time.
Sorry, but I'm afraid I'm not.
barney_parker wrote:
Instead of thinking of a particle as moving at the speed of light, look at it this way. All particles have the same energy, it's just that some distribute it as mass. If a pasticle has no mass it must, by defenition, move at the speed of light in order to compensate for the lack of mass which would otherwise take up it's energy. A Particle with mass can never actually reach the speed of light because it has mass, and by defenition cannot reach the speed of light without removing from it's mass.
The above is all mathematical conjecture, based on concepts that have not been categorically proven. Statistics is another field that is based largely on mathematical conjecture.
barney_parker wrote:
The reason it is though there may be a singularity is to do with pure maths, not physics at all!
Precisely. The problem is that it's the same kind of mathematical thinking that "proves" an expansive spring will expand in direct proportion to the weight applied to it, all the way to infinity. The imaginary numbers concept does have a lot going for it, but beware of calculations that seem to make perfect sense of something we know so little about.
unfortunately your argument against what i have said is pretty poor. The problem with science is it can never prove 100% that anything is true. There are some pretty interesting theory's on it... Your argument seems to come down to "well if you cannot absolutely prove it, it's just not true." I do absolutely accept that just because millions of experiments have not contradicted the theory, you may of course be right, however in order to dis-prove a theory, you must provide some kind of information other than "no, it's not true" Common sense dictates an expansive spring won't and couldn't expand infinitely, so i assume you're talking about an incomplete theory. Both General and Special relativity are incomplete, as Einstein himself said. In fact he spent the later part of his life trying to disprove alot of the results. We could of course go with the the classic theory that says there is a mystical being that we call "God" who made everything, and things only happen according to his "will" but of course that is just phylosphical conjecture... PS, what have statistics got to do with this? or was that just a way of proving your non-existant point?
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longbowaj wrote:
We can see the effects a black hole has on various stars.
No, we can see the effect of gravity on stars -- at least, we can on the occasions when indeed we can. Ask any astronomer how reliable the calculations are that compensate for the effects of gravity of other (visible and non-visible) objects between the observer and the object observed. Everyone seems to think that astronomy is a dead-on, balls-accurate science, but it's nothing of the kind. Sure, when we "see" (without using the visible spectrum) a bright object, we get a general idea of its composition (which could be completely wrong, of course, because the light that reaches us passes through God-only-knows-what on the way here), but there is no way of knowing for sure even as much as whether the object is, say, 120 billion or 150 billion light years away. So we give it our best (computer-assisted) guess about the millions-to-billions of years old light, and mark it down as fact -- which everyone believes as Gospel, because almost no-one appreciates the problems involved. Best guesses are good enough, though, no matter how hugely incorrect they are, because it's pretty damned doubtful that anyone will prove them wrong in the next several lifetimes, if ever. It's the assumptions that are piled on top of these best (but probably hideously inaccurate) guesses that are laughable. Looking through a telescope at a star is absolutely nothing like looking through a telescope at a nearby mountain, no matter how many "speculative thinkers" want to believe it is.
longbowaj wrote:
Also if you don't believe in a black hole then you can not believe in the concept of space-time.
Oh, absolutely. I know nothing.
You're right, we can only see the effects of gravity. Gravity, as far as we are currently able to prove must have a physical source. Therefore it's fair to say we are observing the effect of stars when what we really mean to say it we are seeing the effects of the gravitational pull of stars. I don't think anyone really believes Astronomy is "Balls Accurate". As with any science, it's only as good the the results of the experiments. As for the distance to stars, well i suggest you look up a little geometry and google for the word paralax....it's actually fairly easy, and becomes more accurate with every measurement.... and could you explain in a little more detail why there is a difference between looking at a star and looking at a mountain? I may be wrong but in both cases your observing an object through a medium over a distance. The medium and the object may be known better, but the principal is exactly the same.... On the other hand, I don't believe in Black Holes in the Sci-Fi sense, and good for you, to know you know nothing is the first step to enlightenment..
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Mark Wallace wrote:
What never made sense to me (and still doesn't) is why there should be particles (or whatever they are at any given moment) that just happen to move at the speed that is supposed to be "the fastest speed there is".
What's even more surprising is that there are particles that don't move at that speed.
Mark Wallace wrote:
The truth is probably stranger than the fiction they teach in universities, these days -- but it's probably not so blindly stoopid.
It sure seems to do a good enough job. We definitely have some pretty cool technology based on the fiction that they teach. :|
This blanket smells like ham
Andy Brummer wrote:
Mark Wallace wrote: The truth is probably stranger than the fiction they teach in universities, these days -- but it's probably not so blindly stoopid. It sure seems to do a good enough job. We definitely have some pretty cool technology based on the fiction that they teach.
Absolutely! I guess we could go back to the whole God thing, but that just seems a little out dates these days (although it might be true!) I personally find I tend to belive what gets results. So far GR has given us a mass of technology that we didn't have before it, and it's really still in it's infancy. Mark: You've said alot about what you don't believe, but what do you believe? or are you going to end with "well it's not my job to do the work...". It's always easy to criticise, it's hard to try and work something out...
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I'm gonna have to say Bah on that. Lots of people called it FTL drives, mostly because it doesn't specify the technology used to achieve it. "Spooling up the FTL drive" however is a new and shiny from the new Battlestar Galactica tv series (what guy doesn't like supermodel-nympho-cylons?)
but not giving any scientific detail os the key to any great sci-fi.....avoid the sci, keep to the fi.....
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Kevin McFarlane wrote:
I've always thought this was strange from the time I first read about it when I was about 17. The constancy of the speed of light relative to all observers[^]
What never made sense to me (and still doesn't) is why there should be particles (or whatever they are at any given moment) that just happen to move at the speed that is supposed to be "the fastest speed there is". That really Does Not make any sense, so we're still missing something from the equation. And black holes? I've been arguing against their existence for over 25 years -- with Physics professors, not one of whom has managed to prove (even mathematically, with any real conviction) that they do exist. The truth is probably stranger than the fiction they teach in universities, these days -- but it's probably not so blindly stoopid.
Well just to add something cool and interesting to the discussion, have a look into the Voyager missions. Those things are still out there, in fact Voyager 1 was 30 a couple of days ago! The interesting thing is that over time they should have slowed down due to the pull of the sun. The actual measurements show that they haven't slowed as much as they should, which suggests the theorys about Gravity are missing something over larger distances. Thats pretty surprising when you consider they work at the planetary and galactic levels....
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Kevin McFarlane wrote:
I've always thought this was strange from the time I first read about it when I was about 17. The constancy of the speed of light relative to all observers[^]
What never made sense to me (and still doesn't) is why there should be particles (or whatever they are at any given moment) that just happen to move at the speed that is supposed to be "the fastest speed there is". That really Does Not make any sense, so we're still missing something from the equation. And black holes? I've been arguing against their existence for over 25 years -- with Physics professors, not one of whom has managed to prove (even mathematically, with any real conviction) that they do exist. The truth is probably stranger than the fiction they teach in universities, these days -- but it's probably not so blindly stoopid.
Mark Wallace wrote:
that they do exist.
Not that they do exist, no, but that they can exist.
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You're right, we can only see the effects of gravity. Gravity, as far as we are currently able to prove must have a physical source. Therefore it's fair to say we are observing the effect of stars when what we really mean to say it we are seeing the effects of the gravitational pull of stars. I don't think anyone really believes Astronomy is "Balls Accurate". As with any science, it's only as good the the results of the experiments. As for the distance to stars, well i suggest you look up a little geometry and google for the word paralax....it's actually fairly easy, and becomes more accurate with every measurement.... and could you explain in a little more detail why there is a difference between looking at a star and looking at a mountain? I may be wrong but in both cases your observing an object through a medium over a distance. The medium and the object may be known better, but the principal is exactly the same.... On the other hand, I don't believe in Black Holes in the Sci-Fi sense, and good for you, to know you know nothing is the first step to enlightenment..
barney_parker wrote:
You're right, we can only see the effects of gravity. Gravity, as far as we are currently able to prove must have a physical source. Therefore it's fair to say we are observing the effect of stars when what we really mean to say it we are seeing the effects of the gravitational pull of stars.
The gravitational pull of stars and other objects. Even dust clouds have mass, and we can't even see them, despite the fact that their gravity (and reflectiveness/refractive potential/etc.) has an effect on the tiny little whimper of electromagnetic radiation (including the visible spectrum) that reaches us.
barney_parker wrote:
and could you explain in a little more detail why there is a difference between looking at a star and looking at a mountain? I may be wrong but in both cases your observing an object through a medium over a distance. The medium and the object may be known better, but the principal is exactly the same....
I have no problem with the principle; it's the reality that's the bug-bear. Try using a telescope to look at a mountain through a piece of glass that has a minor scratch. Then two pieces of glass with a minor scratch each. Then three. Then a few billion of them. And that's only the optical problem; then there's the gravity of bright objects (i.e. stars, radiation sources, and the few things we can actually see -- if it doesn't emit or reflect electromagnetic radiation, we don't even know it's there). And, of course, the gravity of dark objects. We can barely see a few of the rocks in our own solar system, and that's with a huge light source nearby (the Sun, not that town in Nevada), but the cumulative effect of all the rocks we can and can't see is a lot of gravity. Another "old favourite" is that if you point at a star, at night, you're pointing at where it was millions of years ago, no? "No" is right. The radiation that finally reaches our pitifully small target has been bent, distorted, and generally mucked with by God only knows how many influences, so the chance of the star ever having been anywhere near where you point is so small that it's not even worth considering. And its actual position is impossible to calculate. A better analogy would be: Try looking at a mountain through a milkshake that's been crammed full of contact-lenses.
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Mark Wallace wrote:
Nothing is simpler than wrong mathematics.
The physics are wrong in your example, but there is no problem with the math.
Mark Wallace wrote:
just dump 300 billion kilos on a four-inch expansive spring that expands precisely one inch per kilo, and it will expand precisely 300 billion inches.
:confused:, garbage in garbage out I guess. Anyway, so you don't believe in GR? Personally, I consider black holes to be likely, but I wouldn't be surprised if they were eventually supplanted by some other phenomenon given how little we understand about quantum gravity. However, there are tons of observations of objects which can only be described by black holes using classical general relativity.
This blanket smells like ham
Andy Brummer wrote:
I consider black holes to be likely
They're as likely as a four-inch extensive spring stretching to 300 billion inches. Black hole theory has all been worked out mathematically. There is no (repeat: N.O.) empirical evidence of black holes. It's a red herring, a Loch Ness monster, a 300-billion-inch spring. Oh, and it's a mathematical /certainty/. Yup. Sure.
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Mark Wallace wrote:
What never made sense to me (and still doesn't) is why there should be particles (or whatever they are at any given moment) that just happen to move at the speed that is supposed to be "the fastest speed there is".
What's even more surprising is that there are particles that don't move at that speed.
Mark Wallace wrote:
The truth is probably stranger than the fiction they teach in universities, these days -- but it's probably not so blindly stoopid.
It sure seems to do a good enough job. We definitely have some pretty cool technology based on the fiction that they teach. :|
This blanket smells like ham
Andy Brummer wrote:
We definitely have some pretty cool technology based on the fiction that they teach.
Ha! Like what? Most invention is by people who've long finished uni, sobered up, grown up, and learned how things really work! (OK, maybe not sobered up or grown up, but you get my drift)
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Andy Brummer wrote:
I consider black holes to be likely
They're as likely as a four-inch extensive spring stretching to 300 billion inches. Black hole theory has all been worked out mathematically. There is no (repeat: N.O.) empirical evidence of black holes. It's a red herring, a Loch Ness monster, a 300-billion-inch spring. Oh, and it's a mathematical /certainty/. Yup. Sure.
lol, thanks! :-D
This blanket smells like ham