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Einstein Said Nothing Can Move Faster Than Light?
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Einstein's theory states nothing can move faster than light. How did we get all the way out here with images from the beginning of time still arriving? It is also accepted that the big bang pushed everything out instantaneously. Surely, the big bang theory proves Einstein wrong.
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I have visited this thread a few times and attempted to read it and educate myself. I have failed but have enjoyed the lively debate.
This is my input http://
One thing that I don't really comprehend about this is - does it matter how it all started? When we have the most probable answer what will we actually do with the information? Are we investigating because we can or because we must?
I am off back to bed to ponder 'stuff'
:-)
This is my input http://
One thing that I don't really comprehend about this is - does it matter how it all started? When we have the most probable answer what will we actually do with the information? Are we investigating because we can or because we must?
I am off back to bed to ponder 'stuff'
:-)
Old Albie has never seen me move when it's my turn to buy a round at the bar. Legs are a blur.. The Road Runner is a dawdler by comparison..
Besides, he couldn't have been THAT smart, he never did learn the basic skill of hair grooming,how to master a comb, a hairbrush, how to visit a barber to get that short back and sides look.
Besides, he couldn't have been THAT smart, he never did learn the basic skill of hair grooming,how to master a comb, a hairbrush, how to visit a barber to get that short back and sides look.
It's one of those things, too, that would be nice to just know, wouldn't it? The pursuit of knowledge and truth is in itself something worth doing, regardless of the benefits we get along the way.
Mind, trying to find out as much as we can about how things work has many tangible benefits too, since the effort involved often requires constructing new technology, and such technology itself is useful. The most well-cited benefit of trying to probe the nature of matter is the current form of the Internet, the WorldWide Web, developed at CERN initially to help particle physicists share their data more easily. More recent developments include some seriously efficient superconductors, which have use in medical technology such as MRI scanners among other things. So I suppose there are two main benefits really: the knowledge itself, and what we need to make and achieve before we can obtain that knowledge.
Mind, trying to find out as much as we can about how things work has many tangible benefits too, since the effort involved often requires constructing new technology, and such technology itself is useful. The most well-cited benefit of trying to probe the nature of matter is the current form of the Internet, the WorldWide Web, developed at CERN initially to help particle physicists share their data more easily. More recent developments include some seriously efficient superconductors, which have use in medical technology such as MRI scanners among other things. So I suppose there are two main benefits really: the knowledge itself, and what we need to make and achieve before we can obtain that knowledge.
Wasn't the 'Big Bang' idea originally conceived as an explanation for why the universe hasn't collapsed under its own weight which is the main stumbling block to a 'steady state' hypothesis? Perhaps the greatest surprise to come along since the 'Hubble Expansion' was first observed, (which is perhaps the strongest supporting evidence for the 'Big Bang') is that this expansion appears to be accelerating!
The universe it seems never ceases to amaze and to throw up more questions about how it could have possibly come to be the way it is the more we learn about it. But then we are all in good company given the difficulties Einstein had coming to grips with the implications of his own theories upon the underlying structure of the universe.
More than this I would like to say, "(Yet another) great post, LG" and to personally "Thank you for your many positive and illuminating contributions to this forum" :o)
OK, I'll shut up now. ;o)
The universe it seems never ceases to amaze and to throw up more questions about how it could have possibly come to be the way it is the more we learn about it. But then we are all in good company given the difficulties Einstein had coming to grips with the implications of his own theories upon the underlying structure of the universe.
More than this I would like to say, "(Yet another) great post, LG" and to personally "Thank you for your many positive and illuminating contributions to this forum" :o)
OK, I'll shut up now. ;o)
I am not disagreeing with the consensus on ekpyrosis (or 'big bang' if we have to call it that).
What I am yet to be convinced about is the association of the CBR with ekpyrosis for the same reason ty_buchanan posed the question that started this discussion.
The CBR has continuously shone down on Earth since it's first detection decades ago and is remarkably ubiquitous in it's signal across the entirety of space visible from this planet. That doesn't look like a one-off flash of light at the start of our universe. If it was, as the original question suggests, how come we can detect it here today?
Hawking on black holes made the comment that they are no longer 'science fiction but science fact'. Apologies for using his choice of words in the consideration of cosmic inflation, it was very puerile of me and I meant no disrespect.
Mathematics. E=mc^2. Inflation sacrifices that fundamental equation in order to explain the universe we see today, hence the original question. I don't need to prove anything because I'm not ready to ditch E=mc^2. Surely it's up to those who propose inflation to explain themselves not those that are understandably reluctant to do so?
It's a bit like theists saying atheists should shut up because they can't prove divinity doesn't exist when atheists are not the ones claiming that it does.
What I am yet to be convinced about is the association of the CBR with ekpyrosis for the same reason ty_buchanan posed the question that started this discussion.
The CBR has continuously shone down on Earth since it's first detection decades ago and is remarkably ubiquitous in it's signal across the entirety of space visible from this planet. That doesn't look like a one-off flash of light at the start of our universe. If it was, as the original question suggests, how come we can detect it here today?
Hawking on black holes made the comment that they are no longer 'science fiction but science fact'. Apologies for using his choice of words in the consideration of cosmic inflation, it was very puerile of me and I meant no disrespect.
Mathematics. E=mc^2. Inflation sacrifices that fundamental equation in order to explain the universe we see today, hence the original question. I don't need to prove anything because I'm not ready to ditch E=mc^2. Surely it's up to those who propose inflation to explain themselves not those that are understandably reluctant to do so?
It's a bit like theists saying atheists should shut up because they can't prove divinity doesn't exist when atheists are not the ones claiming that it does.
I wasn't aware that inflation did violate E=mc^2. Where does that idea come from?
THE CMB isn't a "flash of light" from the beginning of time, but was emitted approximately 380,000 years after the Big Bang (I'm not a fan of the name either, but we may as well stick with it), and from all points in space, when the Universe had cooled sufficiently to allow light to travel unimpeded. Before then, it was opaque to most forms of Electromagnetic radiation, including light. Thus it's a "flash" from everywhere, and probably not an instantaneous one either but one that lasted for some significant length of time.
THE CMB isn't a "flash of light" from the beginning of time, but was emitted approximately 380,000 years after the Big Bang (I'm not a fan of the name either, but we may as well stick with it), and from all points in space, when the Universe had cooled sufficiently to allow light to travel unimpeded. Before then, it was opaque to most forms of Electromagnetic radiation, including light. Thus it's a "flash" from everywhere, and probably not an instantaneous one either but one that lasted for some significant length of time.
I do not pretend to be an expert on these things either Colm, but speed of light maxima relates to objects moving around within the universe- Inflation posits expansion of space-time, the universe itself. No contradiction there.
And if CMBR is a leftover from the initial formative impulse of everything,where everything was compressed in on itself - the very warp and weft of the unverse itself, space-time, It is that which lead to predictions of a universal ubiquitous remnant of that, which CMBR is. I see no contradiction there, either. The CMBR, along with the gravity "ripples" recently observed, exactly match the predictions of the Inflationary model, don't they?
But, as I say, I am no expert in the field, just an enthusiastic amateur. I you can provide a link to an article or publication that offers a model for the universe that better explains and fits the observed phenomena, I would be interested to read it.
It is also undoubtedly true that there will be some physicists who cherish their chosen model, but unlike those of religion, evidence counts, eventually. Just because someone is outside the consensus does not automatically mean they are the Galileo, and those holding to the orthodoxy are the Catholic Church.
@MIBN Very kind of you, thanks :)
And if CMBR is a leftover from the initial formative impulse of everything,where everything was compressed in on itself - the very warp and weft of the unverse itself, space-time, It is that which lead to predictions of a universal ubiquitous remnant of that, which CMBR is. I see no contradiction there, either. The CMBR, along with the gravity "ripples" recently observed, exactly match the predictions of the Inflationary model, don't they?
But, as I say, I am no expert in the field, just an enthusiastic amateur. I you can provide a link to an article or publication that offers a model for the universe that better explains and fits the observed phenomena, I would be interested to read it.
It is also undoubtedly true that there will be some physicists who cherish their chosen model, but unlike those of religion, evidence counts, eventually. Just because someone is outside the consensus does not automatically mean they are the Galileo, and those holding to the orthodoxy are the Catholic Church.
@MIBN Very kind of you, thanks :)
Colmc54 //Hawking on black holes made the comment that they are no longer 'science fiction but science fact'. //
We actually Hawking has recently come full circle and is currently against Black Holes.
This kind of thinking is what make science so powerful. Most serious scientists put most of their effort into looking for the anomalies that would indicate their current theories are off the mark.
It is quacks quoted by scowie that have their pet ideas and avoid any real thinking.
We actually Hawking has recently come full circle and is currently against Black Holes.
This kind of thinking is what make science so powerful. Most serious scientists put most of their effort into looking for the anomalies that would indicate their current theories are off the mark.
It is quacks quoted by scowie that have their pet ideas and avoid any real thinking.
Beso, //Most serious scientists put most of their effort into looking for the anomalies that would indicate their current theories are off the mark.//
I agree, but that’s not the impression I get here. It seems most of the time is spent defending their theories rather than considering for a moment that they might be off the mark.
I agree, but that’s not the impression I get here. It seems most of the time is spent defending their theories rather than considering for a moment that they might be off the mark.
Then again, it's a bit much to expect that the Answerbank is going to be filled with cutting-edge Scientific thought. I come here to present what I believe to be the fairest possible picture to give about the current state of play. My day job is about exploring [one of] the [small] gaps in our understanding -- as is the same for most scientists.
Necessarily there's a level of false impression given by Scientists to the media about how things work. I think the best way of defending this is that it's a lot easier to appreciate what we don't know if you first understand what we do know, and why we think we do know it.
Another reason is that people do have a tendency to want clear, concise answers, of which there are fairly few in Science. Everything that is "known" is quantified in terms of experimental and theoretical uncertainties, which are rather a lot harder to communicate.
So yes, there is a false impression to an extent, but it's a well-motivated one.
Necessarily there's a level of false impression given by Scientists to the media about how things work. I think the best way of defending this is that it's a lot easier to appreciate what we don't know if you first understand what we do know, and why we think we do know it.
Another reason is that people do have a tendency to want clear, concise answers, of which there are fairly few in Science. Everything that is "known" is quantified in terms of experimental and theoretical uncertainties, which are rather a lot harder to communicate.
So yes, there is a false impression to an extent, but it's a well-motivated one.
Well thank you!
Actually, both are correct. The University pays me to teach, and the STFC pays me to study. Each month I receive a payslip, and I draw a stipend. It's probably not a job in the normal definition, to be sure, but unlike when I was an undergraduate I am now paid to study, so it's sort of straddling the boundary between a "real" job and university study.
Hope that clears up any confusion. Technically I'm a postgraduate research student, but I still get paid so it's sort of a job, and it's a job where I do research (hopefully).
Actually, both are correct. The University pays me to teach, and the STFC pays me to study. Each month I receive a payslip, and I draw a stipend. It's probably not a job in the normal definition, to be sure, but unlike when I was an undergraduate I am now paid to study, so it's sort of straddling the boundary between a "real" job and university study.
Hope that clears up any confusion. Technically I'm a postgraduate research student, but I still get paid so it's sort of a job, and it's a job where I do research (hopefully).
I'm following on my pad but am moving home right now and only normally post from my pc. I look forward to contributing further but on a pad I just find my enthusiasm constrained.
So it's OK for inflation to violate the light barrier because it has been decided that otherwise it couldn't have happened. So that is proof that there is no light barrier when it comes to theoretical models of how the universe we live in began, and at the heart of it the cosmic background radiation is the main issue.
I still, for my many sins have a suspicion that it comes from beyond our universe. Is there any way it can be proved to have not?
So it's OK for inflation to violate the light barrier because it has been decided that otherwise it couldn't have happened. So that is proof that there is no light barrier when it comes to theoretical models of how the universe we live in began, and at the heart of it the cosmic background radiation is the main issue.
I still, for my many sins have a suspicion that it comes from beyond our universe. Is there any way it can be proved to have not?
"...OK for inflation to violate the light barrier because it has been decided that otherwise it couldn't have happened."
Like I said befor,e the light barrier only applies to things that have mass and energy and substance. Space and time are not "things" in this sense, and so there is no restriction on their speed. Two analogies earlier in this thread, one from Old Geezer explaining about how shadows can move at any speed, and one from my about waves hitting a beach, demonstrate that it is, in fact, easy to find scenarios in which things appear to be breaking the light barrier. In both cases those things are just points of reference, though, and so relativity is not violated at all, and nothing has broken down, nor is there any sort of cheat.
Spacetime is the ultimate "point of reference". It's just how you define where things are, and when they are there. There is no substance to it, really. And if there is no substance, there is no barrier, and if there is no barrier, there is no problem.
The phenomenon is, properly, known as "metric expansion", and the idea is firmly established in the Scientific field. It is, perhaps, one of the toughest subjects to communicate, not least because it's one of the toughest subjects to understand properly. Nevertheless, that there are in fact several easy scenarios in which you could cause some point of reference to move as an arbitrarily fast speed shows you that the idea of Inflation itself is absolutely not a cheat way. Relativity (in this case General Relativity) applies to it too, just as much as it does to anything else.
* * * * * * *
In terms of your other question:
"[I still think that the CMB] comes from beyond our universe. Is there any way it can be proved to have not?"
The answer to that is probably something closer to "it depends". I may have noted, either in this thread or the other one about Inflation that I posted myself, that there have been attempts to test the idea that our Universe is smaller than it's "observed" to be. This could emerge from models in which you imagine the Universe, say, to be sort of a cube, with the faces acting perhaps as some sort of mirror. These are bizarre ideas, to say the least, but it is possible to go from the idea to some sort of prediction of the pattern it would create in the CMB. Essentially, you should see that the pattern repeats in some way, so that you see the same image in two or more separate points in the sky. So far, this has not been observed despite the searching.
There are two main caveats, though, to this being taken to rule the idea out. Firstly, you have to be able to go from some sort of conceptual idea to some sort of physical prediction that can be tested against the results, and this is not at all easy. And secondly, as you can perhaps just about imagine, the prediction made is highly dependent on the initial assumptions on the shape of the Universe, so that those shapes that have not been tested haven't been ruled out, either.
This can be applied to your idea too. It could be ruled out (to within experimental constraints, at least) if there were some way to turn the sketch into a prediction. This, though, would probably not be easy, and would probably not be definitive either because presumably there are many ways in which you could turn the idea into maths. Each individual idea could be ruled out, but the concept as a whole might never be. And that's even supposing that anyone bothers to try, which isn't guaranteed either, what with the success of the current model to describe what is going on. The accuracy of the fit of model to data is superb.
Like I said befor,e the light barrier only applies to things that have mass and energy and substance. Space and time are not "things" in this sense, and so there is no restriction on their speed. Two analogies earlier in this thread, one from Old Geezer explaining about how shadows can move at any speed, and one from my about waves hitting a beach, demonstrate that it is, in fact, easy to find scenarios in which things appear to be breaking the light barrier. In both cases those things are just points of reference, though, and so relativity is not violated at all, and nothing has broken down, nor is there any sort of cheat.
Spacetime is the ultimate "point of reference". It's just how you define where things are, and when they are there. There is no substance to it, really. And if there is no substance, there is no barrier, and if there is no barrier, there is no problem.
The phenomenon is, properly, known as "metric expansion", and the idea is firmly established in the Scientific field. It is, perhaps, one of the toughest subjects to communicate, not least because it's one of the toughest subjects to understand properly. Nevertheless, that there are in fact several easy scenarios in which you could cause some point of reference to move as an arbitrarily fast speed shows you that the idea of Inflation itself is absolutely not a cheat way. Relativity (in this case General Relativity) applies to it too, just as much as it does to anything else.
* * * * * * *
In terms of your other question:
"[I still think that the CMB] comes from beyond our universe. Is there any way it can be proved to have not?"
The answer to that is probably something closer to "it depends". I may have noted, either in this thread or the other one about Inflation that I posted myself, that there have been attempts to test the idea that our Universe is smaller than it's "observed" to be. This could emerge from models in which you imagine the Universe, say, to be sort of a cube, with the faces acting perhaps as some sort of mirror. These are bizarre ideas, to say the least, but it is possible to go from the idea to some sort of prediction of the pattern it would create in the CMB. Essentially, you should see that the pattern repeats in some way, so that you see the same image in two or more separate points in the sky. So far, this has not been observed despite the searching.
There are two main caveats, though, to this being taken to rule the idea out. Firstly, you have to be able to go from some sort of conceptual idea to some sort of physical prediction that can be tested against the results, and this is not at all easy. And secondly, as you can perhaps just about imagine, the prediction made is highly dependent on the initial assumptions on the shape of the Universe, so that those shapes that have not been tested haven't been ruled out, either.
This can be applied to your idea too. It could be ruled out (to within experimental constraints, at least) if there were some way to turn the sketch into a prediction. This, though, would probably not be easy, and would probably not be definitive either because presumably there are many ways in which you could turn the idea into maths. Each individual idea could be ruled out, but the concept as a whole might never be. And that's even supposing that anyone bothers to try, which isn't guaranteed either, what with the success of the current model to describe what is going on. The accuracy of the fit of model to data is superb.
Sorry to play devil's advocate again but if I may, turn to red/blue -shift. Is it not true that it can be created at both ends of a photons journey? If it was generated mainly at it's origin then the contemporary universe we inhabit today could even be stationary, or even contracting under gravity. Why is the assumption made that the red shift is predominantly created at our end leading to the idea that the universe is expanding, even accelerating in it's expansion?
As far as I can understand the phenomenon there is no way to tell the difference, but yet it appears to be assumed that the spectral lines are red-shifted more, if not completely, at our end of the journey.
As far as I can understand the phenomenon there is no way to tell the difference, but yet it appears to be assumed that the spectral lines are red-shifted more, if not completely, at our end of the journey.
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