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The whole point of the recent BBC program on this is that they DON'T view it as the beginning of time.
Segments of the program are on Youtube and you can see experts in early universe cosmology again and again saying NO they don't think that.
And even one or two case where a seminar room full of scientists was asked to raise their hands and take a "vote" on what their hunch was on that issue. And overwhelmingly they expressed the opinion that it was NOT the beginning of time.
So you may be getting your ideas from out-of-date popularizations. Don't trust any pop-sci, but especially don't trust stale pop-sci.
Here's a sample 10 minute segment on YouTube from the recent BBC program
"What Happened before the Big Bang"
http://www.youtube.com/watch?v=c7vTQ3Z9fmY
I don't recommend it or say anybody should believe it, because it is a popularization---dressed up to appeal to mass audience. That leads to distortion. But at least it isn't completely out of date.
So contemporary science states that the universe has been contracting and expanding. But whatever we state there is still this problem: how does an infinity of movement make sense? how can there not be a beginning? there must have been a point before points where there was no time and thus no movement. And out of this how can there emerge a universe, seeing as the absence of time does not allow for a trigger movement.
I have always asked the question...How can something happen when there is no time for it to happen or no place for it to happen? But I have just read a book called Endless Universe that addresses this problem. It is about M theory. I bought the book because they came up with a theory that seemed at least to be original. I am not sure I buy the whole thing mind you, but it did peak my interest.
Another question I have always asked is this; how do you make something from nothing?
Another question would be; How do you turn something into nothing?
Maybe the universe has always existed in one form or another. Maybe man isn't smart enough to figure it out. Maybe man is...once again I don't know.
Maybe numbers don't tell the whole story...or maybe there is something we are all missing right under our noses.
Although i this use to think this was proof of the existence of God, to me it makes no sense at all once more, for even God was present in this period where there was no time, how could he then have the will to trigger the creation of the universe, if there was no time existing for him to have that will. then the answer is that the will always there in this period(if you can call it that) before time, but then if it was always present how did he trigger it at a certain moment. But wait, there isn't even a time line so there was no waiting, there must be a place where there is no place, where there is no time that god is existent in, where he always had the will to create the universe, where he created the universe from.
That book was by Steinhardt and Turok.
Turok is interviewed in that 1-hour BBC program I gave link to. If you liked the book, you might like the video.
He comes in at minute 7 of video #2. Michio Kaku has just been talking (what I think is garbage) for much of the first 7 minutes. Then Turok comes on and rips him apart!
(Not to his face, but referring to his ideas on an abstract level.)
Turok used to be at Cambridge, when he wrote Endless Universe. Then a year or so ago he moved to Canada to be Director of the Perimeter Institute. A lot of the BBC video was made at Perimeter.
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The BBC program "What happened before the Big Bang" is divided into 6 YouTube segments, each 10 minutes. If you watch a few or all of the segments you will realize that the issue is not resolved. "Science" does not agree on a single version of the story. It is something people are still working on.
There is no consensus.
Like video #3 was divided about half with Param Singh and half with Lee Smolin, both of whom are at Perimeter. And either video #5 or #6 was mostly Roger Penrose, who is at Oxford. Penrose does not agree with either Singh or Smolin. They are working on different ideas. Or Turok (he has his own idea.)
There is a healthy struggle going on. Tug-of-war between different models. Eventually the leading models will have a show-down by comparison with observational data (neutrino telescopes, gravity wave detectors, whatever :-D)
The talk about "something from nothing" does not belong here in Philosophy of Science forum. There is no logical or physical reason why there has to be a beginning. As Turok (and many others) have pointed out, the universe could be endless, time could extend back endlessly.
Time cannot extend back endlessly. Picture yourself traveling back in time (i know it's not possible but just picture it), how could you never reach a final destination? In the realm of time there must be a beginning, that is a law of time. It can go on forever, it can be immortal, but i must have a beginning.
No, contemporary science does not have a consensus. SOME scientists are working on contract/expand models. OTHERS (like Turok) have worked on colliding membrane models. Penrose is working on a very different model---where the infinitely accelerating expansion of our universe (far into the future) BECOMES the big bang initiating the next universe.
These people will have to fight it out. And they will have to compare how their models say things should look with how the data that is gathered looks.
That link I gave is to video segment #3 of the BBC program. It will give you links to the other segments. Watch all 6 of the 10-minute segments if you want. As i said, I think Penrose is either #5 or #6.
You offer no logical or physical grounds for what you say.
You are repeating stuff without giving any supporting reasons. Therefore I am warning you not to repeat this. People who get several warnings normally get banned.
Saying "how could you never reach a final destination?" is not a reason. We know of no reason why there must be a "final destination" going either forwards or backwards in time.
There is a basic rule that when challenged you must either RETRACT a statement like yours, or offer some recognized academic-grade source to back it up, subject to ban. I will not hold you to that rule, since you are new, but I will not tolerate further groundless repetition.
I'm glad you bought and read the book Turok wrote (with Steinhardt). Here is video segment #4 of the BBC program where Turok starts out
http://www.youtube.com/watch?v=wH-GmZaJxLY
Then after 2 minutes, Turok's model gets attacked by Andrei Linde, an old whitehaired Russian who has been promoting "Eternal Inflation" for about 30 years.
So Linde makes a lot of nasty comment for two minutes and then at minute 4 Turok comes back on and counters Linde.
Both of them are offering competing models of "eternal past" type. I don't like either of their models, but at least they are trying to figure out what possibly could have led up to the bang. They are trying, calculating, working out equations etc.
I can respect them for that, even though I don't like either of their pre-bang models.
And I respect you for getting and reading Turok's book. I didn't---I read the free online version of the scientific papers by Steinhardt and Turok that led up to the book. Some years back.
Also I like Turok's personality. He is young and pragmatic and not doctrinaire. He has hired Param Singh who works on a much simpler bounce cosmology model---far simpler than Turok's plus you can calculate stuff with it, computer-model it etc. Closer to testability. So Turok is directing an institute where people are working on competing models of the universe---and he has the courage to support rival approaches and fundamentally I think he doesn't care what idea comes out on top! He wants whatever works and fits the data.
Linde is an old guy who is totally wrapped up in his "eternal inflation" model and attacks rival ideas. Different personality types.
So if you want, you can watch them duke it out for maybe 6 or 8 minutes, I forget how long, in that segment #4. Your author Turok at Perimeter Institute versus old Russian guy Linde at Stanford.
That BBC program is so heavily popularized that I get repelled by it and don't feel like recommending it, but I don't know of any substitute. It's a video that at least gives several different sides of the pre-bang discussion.
Actually the topic doesn't belong in the philosophy of science forum. Philosophy of science typically covers such things as explanations, what are they; theories and observations, scientific methods and what can be said of them; how is scientific knowledge different or the same as ordinary knowledge, and so forth.
As such, I think your topic belongs in the science forum, perhaps within its speculative branch and subject to its rules.
James
I'm going to leave this particular thread here in PoS, Owleye. I will explain why later. But you definitely have a point! First I want to mention that we welcome reputable academic-grade (online if possible :-D) sources. I particularly welcome online scholarly sources because then we can all see what is being said, in context. Also if anyone is bringing supporting source material to bear (on this or any other discussion) please give page references so we can find the passage you are quoting. And please quote, don't rely on possibly inaccurate paraphrase.
I'd be really curious if anybody could come up with a recognized contemporary philosopher who claims that a backwards-in-time sequence of causes has to terminate.
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But on a more serious topic, Owleye, I guess I need to exhibit some example or paragon of PoS. So I will point to the North Holland press (a branch of Elsevier, one of the biggest science publishing companies) and I will point to their standard reference work HANDBOOK IN PHILOSOPHY OF PHYSICS.
And I will suggest that whatever Philosophy of Physics is, it probably bears some resemblance to what the North Holland editors think it is, because they sell to university librarians and departments of philosophy.
So I will give an online sample of the chapter in this handbook that is devoted to Philosophy of Cosmology.
And we can have a look and see what it discusses---that can give a provisional idea of P. of Sci.
It may take a while to get the link. The article is by a renowned Relativist/Cosmologist who co-authored a classic book with Stephen Hawking. You may know the guy: George Ellis.
Speak for yourself Xris, as regards "originality, infinity, nothing". I don't think those concepts are important in cosmology, or in the philosophy of cosmology. If you find them intriguing you can start at thread about them in some other forum.
Time is certainly an important concept. The question I would ask you is do you want to familiarize yourself with contemporary ideas of the nature of time?
Foundational Questions Institute had an essay contest on the nature of time, in 2008. They arranged to have two panels of judges and two sets of prizes. So in particular there were two First Prize essays. If you want, you can read both essays and choose your favorite :-D. I liked both.
Here are links to the two first prize essays:
Rovelli's "Forget Time" http://arxiv.org/abs/0903.3832
Barbour's "The Nature of Time" http://arxiv.org/abs/0903.3489
On reading the lead in to the Ellis essay as well as the handbook abstract, I notice there's much of it that I would put into the category of metaphysics, rather than philosophy of science, generally. This tells me that what is counted as the philosophy of X where X is a particular discipline within science is also to be included within the philosophy of science forum (except where other forums are established for them). So I will retreat.
But so as you understand where I'm coming from, I usually make a distinction between scientists (or mathematicians, historians, social scientists, and so forth) that would have an interest in questions at the edge of their particular discipline that range into the domain of metaphysical inquiry or other speculations about the nature and foundation of their work, and philosophers who wish to make sense of science, generally and specifically, and are coming at it from their perspective and history, they having their own discipline categories that are different than those into which science divides itself. Perhaps this is a distinction without a difference, but it was a helpful one to me when I was reading Einstein's so-called autobiography and the metaphysical speculations in the scientific community that weighed in on the Bohr-Einstein debate over their reading of Quantum Theory. Newton, like Einstein, had philosophical inclinations, but while these inclinations provided them with a way to develop the principles behind their theory, it was the science that resulted that was of most interest to the scientific community and was the reason for its success. In the philosophic community, Kant came a couple of hundred years later and arrived at a metaphysical position that accounted for that success. As far as I'm aware, there hasn't been a philosophical position that equals that of Kant's to account for the universe constructed by Einstein's theory (not for lack of trying; Logical Positivists made some inroads, but ultimately failed) much less that of Quantum theory. Perhaps this contributes to many scientists paying scant attention to philosophers. To philosophy, science is (now and has been for quite a while) a given. Science, however, seems to regard everything pertinent to it to be within its own domain. (I am quite willing to be wrong about these generalizations.)
James
Several interesting points. I think we can be inclusive at PoS forum---we don't want to be too restrictive as to what is PoS and what needs to be moved out. For example I'd be happy to think about TIME here, if you want, or if anybody else has something to contribute. But there are other issues, as you suggest.
BTW I invite you to read this passage, if you wish, and comment:
==quote Rovelli's 2006 essay http://arxiv.org/pdf/gr-qc/0604045 ==
In classical GR, indeed, the notion of time differs strongly from the one used in the special-relativistic context. Before special relativity, one assumed that there is a universal physical variable t, measured by clocks, such that all physical phenomena can be described in terms of evolution equations in the independent variable t. In special relativity, this notion of time is weakened. Clocks do not measure a universal time variable, but only the proper time elapsed along inertial trajectories. If we fix a Lorentz frame, nevertheless, we can still describe all physical phenomena in terms of evolution equations in the independent variable x0, even though this description hides the covariance of the system.
In general relativity, when we describe the dynamics of the gravitational field (not to be confused with the dynamics of matter in a given gravitational field), there is no external time variable that can play the role of observable independent evolution variable. The field equations are written in terms of an evolution parameter, which is the time coordinate x0, but this coordinate, does not correspond to anything directly observable. The proper time τ along spacetime trajectories cannot be used as an independent variable either, as τ is a complicated non-local function of the gravitational field itself.
Therefore, properly speaking, GR does not admit a description as a system evolving in terms of an
observable time variable. This does not mean that GR lacks predictivity. Simply put, what GR
predicts are relations between (partial) observables, which in general cannot be represented as the
evolution of dependent variables on a preferred independent time variable.
This weakening of the notion of time in classical GR is rarely emphasized: After all, in classical
GR we may disregard the full dynamical structure of the theory and consider only individual solutions
of its equations of motion. A single solution of the GR equations of motion determines “a spacetime”,
where a notion of proper time is associated to each timelike worldline.
But in the quantum context a single solution of the dynamical equation is like a single “trajectory” of a quantum particle: in quantum theory there are no physical individual tra jectories: there are only transition probabilities between observable eigenvalues. Therefore in quantum gravity it is likely to be impossible to describe the world in terms of a spacetime, in the same sense in which the motion of a quantum electron cannot be described in terms of a single trajectory.
To make sense of the world at the Planck scale, and to find a consistent conceptual framework for
GR and QM, we might have to give up the notion of time altogether, and learn ways to describe the
world in atemporal terms.
==endquote==
The Fabric of the Cosmos by Brian Greene (Penguin) may be interesting reading. The general conclusion is that scientists (physicists) just don't know what happened. What can be said is that time started when the first indication of something actually happened. For example, the creation of something like space. Nothing can exist without a place (space) for it to happen.
It can be observed that when scientists come up against a brick wall (like that of going back in time to the very beginning), some of their theories do seem more philosophical than scientific. The Higgs boson, for example. This is human nature, isn't it? Without an idea that may be unscientific, a scientific conclusion cannot even be contemplated.
Out of date. Consensus has been shifting at least since 2005. Greene is a good writer and popularizer, but has not produced much important research---no recent highly cited papers.
My advice would be to forget about anything written before 2005, and watch the BBC program.
Greene will bring out a new book in the spring of 2011. My guess is it will present some of these before-bang models. He's not a highly regarded authority (there will be other books by people more in the front line) but if you like his writing style then try reading the new Greene book when it comes out.
Of course "nobody knows", stuff has to be tested and retested. The interesting thing, which a growing number of researchers are interested in, is what are the different models, what do they predict about observable phenomena, how can they be tested, how much fine-tuning do they require (or conversely, how robust and un-finicky are they.) Models that are not fragile tend to attract support---ones that when you simulate the universe in a computer they tend to work pretty much whatever numbers you throw at them---don't break down easily or require fine tuning the input numbers.
Infinity is not interesting because it is a routine concept, like the number 2, or zero, or pi. It is not important to talk about it in cosmology, and people don't. I read professional research in cosmology and people do not discuss about the topic of "infinity". Some things are finite and some are not. It's taken for granted.
Sorry but I find the idea that infinity is accepted as a fact in cosmology as strange concept. It implies infinite matter ...when it is so apparently, is not. Maybe I have the completely wrong idea on what cosmologists consider as important.
Sometimes you're a snob Marshall. The gift of communication and the gift of testing the boundaries are not often both given to the same individual. I know some very incoherent smart people and some people who are smart enough to understand >>and<< be able to translate. Both skill sets are valuable.
I object to the self-perpetuating process of someone getting a best seller, so subsequent publishers and multimedia types go back to the author, thereby elevating their visibility, in a frenzied spiral, until theirs is the only voice heard in the public media. But I don't insist that the errant genius actually write my popularizations.
Heh heh, I don't think either of us is a snob, Lincoln. I admire and value Greene as a talented popularizer. He has a great way with language, charm. He organizes science fairs, inspires young people.
I highly respect people's communication skills, and he is obviously a star.
But the commercial BLURBS for his books, as I recall, portray him as a leading this or that. His actual scientific output is not that great. I think you know what I mean and acknowledge it in what you say---probably know even better than I that as a theorist Greene is minor.
I don't see him in the list of highly cited string papers, or any kind of highly cited research publication. I follow arxiv hep-th fairly regularly and don't see him publishing much of anything these days. I don't see him giving plenary talks at the annual Strings conference.
Like you say, two separate skill-sets!
But just because I say this doesn't mean you have to DEFEND Greene. I am not being mean to him :-D. It is just how things are. I think we both acknowledge it.
Also the string theorists who actually ARE tops, those I've seen, should not be characterized as weird or "different" or poor communicators. The ones I've seen video (or live) are well-spoken and also good communicators (at a science level). I was impressed by the good clear talks , and panel discussion from Andy Strominger (one I most admire), Juan Maldacena, Eva Silverstein, Lisa Randall, R. Bousso...
Any one would be a pleasure to meet and converse with, they just don't write books that inspire highschool students with metaphors and imagery, they work a different crowd.
The big bang
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The big bang
by beef2jerky on October 16th, 2010, 11:25 am
Scientist view the big bang as the beginning of time, seeing as space and time are proclaimed to be one by these same scientists. However, if there is no time, how can there be any movement? If the matter was expanding and collapsing on itself, there must have been some form of ultimate time beyond the time of our universe to record it. If there was no time, then no movement would be possible, is it not so? So either the big bang theory is false, IMO, or it proves the existence of a higher level of time beyond our universe.
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Re: The big bang
by Marshall on October 16th, 2010, 1:00 pm
beef2jerky wrote:Scientist view the big bang as the beginning of time, seeing as space and time are proclaimed to be one by these same scientists. However, if there is no time, how can there be any movement? If the matter was expanding and collapsing on itself, there must have been some form of ultimate time beyond the time of our universe to record it. If there was no time, then no movement would be possible, is it not so? So either the big bang theory is false, IMO, or it proves the existence of a higher level of time beyond our universe.
The whole point of the recent BBC program on this is that they DON'T view it as the beginning of time.
Segments of the program are on Youtube and you can see experts in early universe cosmology again and again saying NO they don't think that.
And even one or two case where a seminar room full of scientists was asked to raise their hands and take a "vote" on what their hunch was on that issue. And overwhelmingly they expressed the opinion that it was NOT the beginning of time.
So you may be getting your ideas from out-of-date popularizations. Don't trust any pop-sci, but especially don't trust stale pop-sci.
Here's a sample 10 minute segment on YouTube from the recent BBC program
"What Happened before the Big Bang"
http://www.youtube.com/watch?v=c7vTQ3Z9fmY
I don't recommend it or say anybody should believe it, because it is a popularization---dressed up to appeal to mass audience. That leads to distortion. But at least it isn't completely out of date.
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Re: The big bang
by beef2jerky on October 16th, 2010, 8:04 pm
Marshall wrote:
The whole point of the recent BBC program on this is that they DON'T view it as the beginning of time.
Segments of the program are on Youtube and you can see experts in early universe cosmology again and again saying NO they don't think that.
And even one or two case where a seminar room full of scientists was asked to raise their hands and take a "vote" on what their hunch was on that issue. And overwhelmingly they expressed the opinion that it was NOT the beginning of time.
So you may be getting your ideas from out-of-date popularizations. Don't trust any pop-sci, but especially don't trust stale pop-sci.
Here's a sample 10 minute segment on YouTube from the recent BBC program
"What Happened before the Big Bang"
http://www.youtube.com/watch?v=c7vTQ3Z9fmY
I don't recommend it or say anybody should believe it, because it is a popularization---dressed up to appeal to mass audience. That leads to distortion. But at least it isn't completely out of date.
So contemporary science states that the universe has been contracting and expanding. But whatever we state there is still this problem: how does an infinity of movement make sense? how can there not be a beginning? there must have been a point before points where there was no time and thus no movement. And out of this how can there emerge a universe, seeing as the absence of time does not allow for a trigger movement.
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Re: The big bang
by bamahick on October 16th, 2010, 8:22 pm
beef2jerky wrote:Scientist view the big bang as the beginning of time, seeing as space and time are proclaimed to be one by these same scientists. However, if there is no time, how can there be any movement? If the matter was expanding and collapsing on itself, there must have been some form of ultimate time beyond the time of our universe to record it. If there was no time, then no movement would be possible, is it not so? So either the big bang theory is false, IMO, or it proves the existence of a higher level of time beyond our universe.
I have always asked the question...How can something happen when there is no time for it to happen or no place for it to happen? But I have just read a book called Endless Universe that addresses this problem. It is about M theory. I bought the book because they came up with a theory that seemed at least to be original. I am not sure I buy the whole thing mind you, but it did peak my interest.
Another question I have always asked is this; how do you make something from nothing?
Another question would be; How do you turn something into nothing?
Maybe the universe has always existed in one form or another. Maybe man isn't smart enough to figure it out. Maybe man is...once again I don't know.
Maybe numbers don't tell the whole story...or maybe there is something we are all missing right under our noses.
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Re: The big bang
by beef2jerky on October 16th, 2010, 8:37 pm
beef2jerky wrote:
So contemporary science states that the universe has been contracting and expanding. But whatever we state there is still this problem: how does an infinity of movement make sense? how can there not be a beginning? there must have been a point before points where there was no time and thus no movement. And out of this how can there emerge a universe, seeing as the absence of time does not allow for a trigger movement.
Although i this use to think this was proof of the existence of God, to me it makes no sense at all once more, for even God was present in this period where there was no time, how could he then have the will to trigger the creation of the universe, if there was no time existing for him to have that will. then the answer is that the will always there in this period(if you can call it that) before time, but then if it was always present how did he trigger it at a certain moment. But wait, there isn't even a time line so there was no waiting, there must be a place where there is no place, where there is no time that god is existent in, where he always had the will to create the universe, where he created the universe from.
Last edited by beef2jerky on October 16th, 2010, 8:50 pm, edited 1 time in total.
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Re: The big bang
by beef2jerky on October 16th, 2010, 8:49 pm
All in all i think existence just doesn't make sense, there should logically be nothing, but alas, there is something. Will we ever understand existence?
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Re: The big bang
by Marshall on October 16th, 2010, 10:02 pm
bamahick wrote:... I have just read a book called Endless Universe that addresses this problem....
That book was by Steinhardt and Turok.
Turok is interviewed in that 1-hour BBC program I gave link to. If you liked the book, you might like the video.
He comes in at minute 7 of video #2. Michio Kaku has just been talking (what I think is garbage) for much of the first 7 minutes. Then Turok comes on and rips him apart!
(Not to his face, but referring to his ideas on an abstract level.)
Turok used to be at Cambridge, when he wrote Endless Universe. Then a year or so ago he moved to Canada to be Director of the Perimeter Institute. A lot of the BBC video was made at Perimeter.
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The BBC program "What happened before the Big Bang" is divided into 6 YouTube segments, each 10 minutes. If you watch a few or all of the segments you will realize that the issue is not resolved. "Science" does not agree on a single version of the story. It is something people are still working on.
There is no consensus.
Like video #3 was divided about half with Param Singh and half with Lee Smolin, both of whom are at Perimeter. And either video #5 or #6 was mostly Roger Penrose, who is at Oxford. Penrose does not agree with either Singh or Smolin. They are working on different ideas. Or Turok (he has his own idea.)
There is a healthy struggle going on. Tug-of-war between different models. Eventually the leading models will have a show-down by comparison with observational data (neutrino telescopes, gravity wave detectors, whatever :-D)
The talk about "something from nothing" does not belong here in Philosophy of Science forum. There is no logical or physical reason why there has to be a beginning. As Turok (and many others) have pointed out, the universe could be endless, time could extend back endlessly.
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Re: The big bang
by beef2jerky on October 16th, 2010, 10:11 pm
Marshall wrote: There is no logical or physical reason why there has to be a beginning. As Turok (and many others) have pointed out, the universe could be endless, time could extend back endlessly.
Time cannot extend back endlessly. Picture yourself traveling back in time (i know it's not possible but just picture it), how could you never reach a final destination? In the realm of time there must be a beginning, that is a law of time. It can go on forever, it can be immortal, but i must have a beginning.
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Re: The big bang
by Marshall on October 16th, 2010, 10:15 pm
beef2jerky wrote:Marshall wrote:Here's a sample 10 minute segment on YouTube from the recent BBC program
"What Happened before the Big Bang"
http://www.youtube.com/watch?v=c7vTQ3Z9fmY
I don't recommend it or say anybody should believe it, because it is a popularization---dressed up to appeal to mass audience. That leads to distortion. But at least it isn't completely out of date.
So contemporary science states that the universe has been contracting and expanding...
No, contemporary science does not have a consensus. SOME scientists are working on contract/expand models. OTHERS (like Turok) have worked on colliding membrane models. Penrose is working on a very different model---where the infinitely accelerating expansion of our universe (far into the future) BECOMES the big bang initiating the next universe.
These people will have to fight it out. And they will have to compare how their models say things should look with how the data that is gathered looks.
That link I gave is to video segment #3 of the BBC program. It will give you links to the other segments. Watch all 6 of the 10-minute segments if you want. As i said, I think Penrose is either #5 or #6.
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Re: The big bang
by Marshall on October 16th, 2010, 10:25 pm
beef2jerky wrote:Marshall wrote: There is no logical or physical reason why there has to be a beginning. As Turok (and many others) have pointed out, the universe could be endless, time could extend back endlessly.
Time cannot extend back endlessly. Picture yourself traveling back in time (i know it's not possible but just picture it), how could you never reach a final destination? In the realm of time there must be a beginning, that is a law of time. It can go on forever, it can be immortal, but i must have a beginning.
You offer no logical or physical grounds for what you say.
You are repeating stuff without giving any supporting reasons. Therefore I am warning you not to repeat this. People who get several warnings normally get banned.
Saying "how could you never reach a final destination?" is not a reason. We know of no reason why there must be a "final destination" going either forwards or backwards in time.
There is a basic rule that when challenged you must either RETRACT a statement like yours, or offer some recognized academic-grade source to back it up, subject to ban. I will not hold you to that rule, since you are new, but I will not tolerate further groundless repetition.
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Re: The big bang
by Marshall on October 16th, 2010, 10:58 pm
bamahick wrote:... But I have just read a book called Endless Universe that addresses this problem...
I'm glad you bought and read the book Turok wrote (with Steinhardt). Here is video segment #4 of the BBC program where Turok starts out
http://www.youtube.com/watch?v=wH-GmZaJxLY
Then after 2 minutes, Turok's model gets attacked by Andrei Linde, an old whitehaired Russian who has been promoting "Eternal Inflation" for about 30 years.
So Linde makes a lot of nasty comment for two minutes and then at minute 4 Turok comes back on and counters Linde.
Both of them are offering competing models of "eternal past" type. I don't like either of their models, but at least they are trying to figure out what possibly could have led up to the bang. They are trying, calculating, working out equations etc.
I can respect them for that, even though I don't like either of their pre-bang models.
And I respect you for getting and reading Turok's book. I didn't---I read the free online version of the scientific papers by Steinhardt and Turok that led up to the book. Some years back.
Also I like Turok's personality. He is young and pragmatic and not doctrinaire. He has hired Param Singh who works on a much simpler bounce cosmology model---far simpler than Turok's plus you can calculate stuff with it, computer-model it etc. Closer to testability. So Turok is directing an institute where people are working on competing models of the universe---and he has the courage to support rival approaches and fundamentally I think he doesn't care what idea comes out on top! He wants whatever works and fits the data.
Linde is an old guy who is totally wrapped up in his "eternal inflation" model and attacks rival ideas. Different personality types.
So if you want, you can watch them duke it out for maybe 6 or 8 minutes, I forget how long, in that segment #4. Your author Turok at Perimeter Institute versus old Russian guy Linde at Stanford.
That BBC program is so heavily popularized that I get repelled by it and don't feel like recommending it, but I don't know of any substitute. It's a video that at least gives several different sides of the pre-bang discussion.
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Re: The big bang
by beef2jerky on October 17th, 2010, 12:34 pm
I will try to explain it in a way you find acceptable.take a bouncing ball. every previous bounce is a cause, but for the bouncing ball to logically be bouncing there must be a time when it was lifted off the ground and bounced the first time. That the ball has been bouncing forever is an illogical answer because every effect must have a cause. Evidence is this is seen in our universe, every effect in our universe has had a cause, the problem is that we cannot explain how the first cause was caused, so we come to the easy conclusion that there was no first cause, which is just giving up. There is no effect in this universe that cannot be traced back to a cause. If i draw a dot on a an infinitely long piece of paper, and i draw back a line to represent the time line of the universe, i can keep drawing that line for all eternity, but that is because in reality, i am drawing into the future. Saying that there are infinite causes may not seem like a big leap when we are overwhelmed by the vast amount of time the universe has been going on. But when we look at it with a clear mind from a logical and philosophical point of view, we understand it is fallacy, there cannot be an infinite causes, because a cause must have a first cause to logically happen. The video that i saw doesn't answer that question, it just presents new causes to temporarily satisfy our confusion.
Btw this is not a science forum, it's a philosophy forum about science, so i think this is an appropriate response.
Btw this is not a science forum, it's a philosophy forum about science, so i think this is an appropriate response.
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Re: The big bang
by Marshall on October 17th, 2010, 1:08 pm
I said two posts back, when I explicitly warned b2j about this, that I would not tolerate further groundless repetition--and have acted accordingly.beef2jerky wrote:... there cannot be an infinite causes, because a cause must have a first cause to logically happen...
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Re: The big bang
by Marshall on October 17th, 2010, 1:30 pm
In human language like English etc the world can be described/explained in terms of a sequence of discrete causes. Maybe an oversimplification but it's still a useful approximation that often works quite well. This was caused by that, which in turn was caused by something else, and so on back in time.
Symbolically, some event C0 was caused by C1 which was caused by C2 which in turn was caused by C3, and so on.
Logically the sequence of antecedents does not have to terminate.
So far I've just said something about the language we use to describe and explain, and the common everyday logic governing its use.
There is also the physical idea of time, and it is also true that there is no physical reason why time---and the temporal evolution of the universe---cannot extend back endlessly into the past.
Symbolically, some event C0 was caused by C1 which was caused by C2 which in turn was caused by C3, and so on.
Logically the sequence of antecedents does not have to terminate.
So far I've just said something about the language we use to describe and explain, and the common everyday logic governing its use.
There is also the physical idea of time, and it is also true that there is no physical reason why time---and the temporal evolution of the universe---cannot extend back endlessly into the past.
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Re: The big bang
by owleye on October 17th, 2010, 1:41 pm
beef2jerky wrote:
Btw this is not a science forum, it's a philosophy forum about science, so i think this is an appropriate response.
Actually the topic doesn't belong in the philosophy of science forum. Philosophy of science typically covers such things as explanations, what are they; theories and observations, scientific methods and what can be said of them; how is scientific knowledge different or the same as ordinary knowledge, and so forth.
As such, I think your topic belongs in the science forum, perhaps within its speculative branch and subject to its rules.
James
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Re: The big bang
by xris on October 17th, 2010, 2:23 pm
I think we all have problems with certain concepts..Originality, infinity , nothing and the very idea of time. The Big Bang combines all those difficult concepts and becomes more elusive, the more we speculate. I am only glad we have such mysteries, how boring would life be without them.
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Re: The big bang
by Marshall on October 17th, 2010, 2:45 pm
owleye wrote:... Philosophy of science typically covers such things as explanations, what are they; theories and observations, scientific methods and what can be said of them; how is scientific knowledge different or the same as ordinary knowledge, and so forth.
As such, I think your topic belongs in the science forum, perhaps within its speculative branch and subject to its rules.
...
I'm going to leave this particular thread here in PoS, Owleye. I will explain why later. But you definitely have a point! First I want to mention that we welcome reputable academic-grade (online if possible :-D) sources. I particularly welcome online scholarly sources because then we can all see what is being said, in context. Also if anyone is bringing supporting source material to bear (on this or any other discussion) please give page references so we can find the passage you are quoting. And please quote, don't rely on possibly inaccurate paraphrase.
I'd be really curious if anybody could come up with a recognized contemporary philosopher who claims that a backwards-in-time sequence of causes has to terminate.
================================
But on a more serious topic, Owleye, I guess I need to exhibit some example or paragon of PoS. So I will point to the North Holland press (a branch of Elsevier, one of the biggest science publishing companies) and I will point to their standard reference work HANDBOOK IN PHILOSOPHY OF PHYSICS.
And I will suggest that whatever Philosophy of Physics is, it probably bears some resemblance to what the North Holland editors think it is, because they sell to university librarians and departments of philosophy.
So I will give an online sample of the chapter in this handbook that is devoted to Philosophy of Cosmology.
And we can have a look and see what it discusses---that can give a provisional idea of P. of Sci.
It may take a while to get the link. The article is by a renowned Relativist/Cosmologist who co-authored a classic book with Stephen Hawking. You may know the guy: George Ellis.
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Re: The big bang
by Marshall on October 17th, 2010, 3:58 pm
I couldn't find Ellis' Handbook article right away, but here is a 2009 CONFERENCE ON PHIL. OF COSM.
http://astroweb1.physics.ox.ac.uk/~philcosmo2009/home
involving the world's top people in this field, Ellis being one of the organizers
I'll keep looking
Here we go!
http://www.mth.uct.ac.za/~ellis/enc2.pdf
This is a 60-page essay by Ellis called "Issues in the Philosophy of Cosmology".
Have a look! I think it is a good way to understand what is meant by "Philosophy of Cosmology" and, by extension "Philosophy of Physics".
I will look for an alternative link to that same essay, in case it works better.
Here we go:
http://arxiv.org/abs/astro-ph/0602280
This is what was published in Elsevier's Handbook in Philosophy of Physics.
http://astroweb1.physics.ox.ac.uk/~philcosmo2009/home
involving the world's top people in this field, Ellis being one of the organizers
I'll keep looking
Here we go!
http://www.mth.uct.ac.za/~ellis/enc2.pdf
This is a 60-page essay by Ellis called "Issues in the Philosophy of Cosmology".
Have a look! I think it is a good way to understand what is meant by "Philosophy of Cosmology" and, by extension "Philosophy of Physics".
I will look for an alternative link to that same essay, in case it works better.
Here we go:
http://arxiv.org/abs/astro-ph/0602280
This is what was published in Elsevier's Handbook in Philosophy of Physics.
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Re: The big bang
by Marshall on October 17th, 2010, 4:23 pm
xris wrote:I think we all have problems with certain concepts..Originality, infinity , nothing and the very idea of time. The Big Bang combines all those difficult concepts and becomes more elusive, the more we speculate. I am only glad we have such mysteries, how boring would life be without them.
Speak for yourself Xris, as regards "originality, infinity, nothing". I don't think those concepts are important in cosmology, or in the philosophy of cosmology. If you find them intriguing you can start at thread about them in some other forum.
Time is certainly an important concept. The question I would ask you is do you want to familiarize yourself with contemporary ideas of the nature of time?
Foundational Questions Institute had an essay contest on the nature of time, in 2008. They arranged to have two panels of judges and two sets of prizes. So in particular there were two First Prize essays. If you want, you can read both essays and choose your favorite :-D. I liked both.
Here are links to the two first prize essays:
Rovelli's "Forget Time" http://arxiv.org/abs/0903.3832
Barbour's "The Nature of Time" http://arxiv.org/abs/0903.3489
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Re: The big bang
by owleye on October 17th, 2010, 6:54 pm
Marshall wrote:I couldn't find Ellis' Handbook article right away, but here is a 2009 CONFERENCE ON PHIL. OF COSM.
http://astroweb1.physics.ox.ac.uk/~philcosmo2009/home
involving the world's top people in this field, Ellis being one of the organizers
I'll keep looking
Here we go!
http://www.mth.uct.ac.za/~ellis/enc2.pdf
This is a 60-page essay by Ellis called "Issues in the Philosophy of Cosmology".
Have a look! I think it is a good way to understand what is meant by "Philosophy of Cosmology" and, by extension "Philosophy of Physics".
I will look for an alternative link to that same essay, in case it works better.
Here we go:
http://arxiv.org/abs/astro-ph/0602280
This is what was published in Elsevier's Handbook in Philosophy of Physics.
On reading the lead in to the Ellis essay as well as the handbook abstract, I notice there's much of it that I would put into the category of metaphysics, rather than philosophy of science, generally. This tells me that what is counted as the philosophy of X where X is a particular discipline within science is also to be included within the philosophy of science forum (except where other forums are established for them). So I will retreat.
But so as you understand where I'm coming from, I usually make a distinction between scientists (or mathematicians, historians, social scientists, and so forth) that would have an interest in questions at the edge of their particular discipline that range into the domain of metaphysical inquiry or other speculations about the nature and foundation of their work, and philosophers who wish to make sense of science, generally and specifically, and are coming at it from their perspective and history, they having their own discipline categories that are different than those into which science divides itself. Perhaps this is a distinction without a difference, but it was a helpful one to me when I was reading Einstein's so-called autobiography and the metaphysical speculations in the scientific community that weighed in on the Bohr-Einstein debate over their reading of Quantum Theory. Newton, like Einstein, had philosophical inclinations, but while these inclinations provided them with a way to develop the principles behind their theory, it was the science that resulted that was of most interest to the scientific community and was the reason for its success. In the philosophic community, Kant came a couple of hundred years later and arrived at a metaphysical position that accounted for that success. As far as I'm aware, there hasn't been a philosophical position that equals that of Kant's to account for the universe constructed by Einstein's theory (not for lack of trying; Logical Positivists made some inroads, but ultimately failed) much less that of Quantum theory. Perhaps this contributes to many scientists paying scant attention to philosophers. To philosophy, science is (now and has been for quite a while) a given. Science, however, seems to regard everything pertinent to it to be within its own domain. (I am quite willing to be wrong about these generalizations.)
James
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Re: The big bang
by Marshall on October 17th, 2010, 10:18 pm
owleye wrote:...I usually make a distinction between scientists (or mathematicians, historians, social scientists, and so forth) that would have an interest in questions at the edge of their particular discipline that range into the domain of metaphysical inquiry or other speculations about the nature and foundation of their work, and philosophers who wish to make sense of science, ...
...
... Newton, like Einstein, had philosophical inclinations, but while these inclinations provided them with a way to develop the principles behind their theory, it was the science that resulted that was of most interest to the scientific community and was the reason for its success. ...
...
... As far as I'm aware, there hasn't been a philosophical position that equals that of Kant's to account for the universe constructed by Einstein's theory ...
...
... Science, however, seems to regard everything pertinent to it to be within its own domain. (I am quite willing to be wrong about these generalizations.)
James
Several interesting points. I think we can be inclusive at PoS forum---we don't want to be too restrictive as to what is PoS and what needs to be moved out. For example I'd be happy to think about TIME here, if you want, or if anybody else has something to contribute. But there are other issues, as you suggest.
BTW I invite you to read this passage, if you wish, and comment:
==quote Rovelli's 2006 essay http://arxiv.org/pdf/gr-qc/0604045 ==
In classical GR, indeed, the notion of time differs strongly from the one used in the special-relativistic context. Before special relativity, one assumed that there is a universal physical variable t, measured by clocks, such that all physical phenomena can be described in terms of evolution equations in the independent variable t. In special relativity, this notion of time is weakened. Clocks do not measure a universal time variable, but only the proper time elapsed along inertial trajectories. If we fix a Lorentz frame, nevertheless, we can still describe all physical phenomena in terms of evolution equations in the independent variable x0, even though this description hides the covariance of the system.
In general relativity, when we describe the dynamics of the gravitational field (not to be confused with the dynamics of matter in a given gravitational field), there is no external time variable that can play the role of observable independent evolution variable. The field equations are written in terms of an evolution parameter, which is the time coordinate x0, but this coordinate, does not correspond to anything directly observable. The proper time τ along spacetime trajectories cannot be used as an independent variable either, as τ is a complicated non-local function of the gravitational field itself.
Therefore, properly speaking, GR does not admit a description as a system evolving in terms of an
observable time variable. This does not mean that GR lacks predictivity. Simply put, what GR
predicts are relations between (partial) observables, which in general cannot be represented as the
evolution of dependent variables on a preferred independent time variable.
This weakening of the notion of time in classical GR is rarely emphasized: After all, in classical
GR we may disregard the full dynamical structure of the theory and consider only individual solutions
of its equations of motion. A single solution of the GR equations of motion determines “a spacetime”,
where a notion of proper time is associated to each timelike worldline.
But in the quantum context a single solution of the dynamical equation is like a single “trajectory” of a quantum particle: in quantum theory there are no physical individual tra jectories: there are only transition probabilities between observable eigenvalues. Therefore in quantum gravity it is likely to be impossible to describe the world in terms of a spacetime, in the same sense in which the motion of a quantum electron cannot be described in terms of a single trajectory.
To make sense of the world at the Planck scale, and to find a consistent conceptual framework for
GR and QM, we might have to give up the notion of time altogether, and learn ways to describe the
world in atemporal terms.
==endquote==
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Re: The big bang
by Marshall on October 17th, 2010, 11:08 pm
James, in response: I agree that great advances in physics have often been made by people like Einstein and Newton who had the sense not to ignore deep philosophical problems. Who had strong interest in the concepts and could reason and debate about philosophical questions. Not just Einstein and Newton, I'm sure you could name a number of others.
You point to a failure of maturation, which Rovelli also talks about. You put it in terms of PHILOSOPHY failing to catch up with 1915 General Relativity. Rovelli describes it more as fundamental particle physics---quantum field theory---being slow to assimilate the concepts---still using a concept of time that goes back to 1905. A revolution which is still incomplete that has to do with concepts---concepts of space and (especially) time. For him it is PARTICLE PHYSICS failing to implement the philosophical insights of gen rel.
Actually a philosophical (conceptual) roadblock has been holding up progress and causing a waste of theoreticians' time. Rovelli's 2006 essay gets into that in the first 3 pages. The string program stalled because of a conceptual requirement which was ignored at the outset---the requirement that a theory not be dependent on a fixed prior spacetime setup---so-called "background independence". Some philosophical analysis at the beginning would have saved much frustration and travail.
It is an example of the hubris you hinted at: theorists getting into trouble because they ignored the need for conceptual groundwork. Whereas Einstein even began with philosophy, probing the concepts with thought experiments, before writing equations.
You know the quote from Clemenceau: "War is too important to be left to the generals." It may be that when it comes to physics, philosophy is too important to leave to the professional philosophers. You have to get amphibious minds like Newton Leibniz Einstein Bohr involved. Just a thought.
Rovelli is an interesting example---trained in both physics and history/philosophy of science. Lectures in philosophy as well as physics! Has written a book on Anaxagoras of Miletus. Has contributed to the Stanford Encyclopedia of Philosophy. Published papers with a philosophical character like "What is a particle?" Operates on several levels. Interesting guy. Shows, in effect, the philosophical ingredient that the string program (for all its mathematical brilliance) was lacking.
Of course hubris and arrogance can work both ways. Somebody should have reminded Clemenceau of the example of Julius Caesar, who could operate both as general and as politician (maybe even better as a politician). And I think of Galileo---the experimenter + philosopher--who led a revolution (who else could have!)
My thoughts are more confused than yours right now, and I'm sleepy. I have no clear orderly conclusions. Just have to stop.
You point to a failure of maturation, which Rovelli also talks about. You put it in terms of PHILOSOPHY failing to catch up with 1915 General Relativity. Rovelli describes it more as fundamental particle physics---quantum field theory---being slow to assimilate the concepts---still using a concept of time that goes back to 1905. A revolution which is still incomplete that has to do with concepts---concepts of space and (especially) time. For him it is PARTICLE PHYSICS failing to implement the philosophical insights of gen rel.
Actually a philosophical (conceptual) roadblock has been holding up progress and causing a waste of theoreticians' time. Rovelli's 2006 essay gets into that in the first 3 pages. The string program stalled because of a conceptual requirement which was ignored at the outset---the requirement that a theory not be dependent on a fixed prior spacetime setup---so-called "background independence". Some philosophical analysis at the beginning would have saved much frustration and travail.
It is an example of the hubris you hinted at: theorists getting into trouble because they ignored the need for conceptual groundwork. Whereas Einstein even began with philosophy, probing the concepts with thought experiments, before writing equations.
You know the quote from Clemenceau: "War is too important to be left to the generals." It may be that when it comes to physics, philosophy is too important to leave to the professional philosophers. You have to get amphibious minds like Newton Leibniz Einstein Bohr involved. Just a thought.
Rovelli is an interesting example---trained in both physics and history/philosophy of science. Lectures in philosophy as well as physics! Has written a book on Anaxagoras of Miletus. Has contributed to the Stanford Encyclopedia of Philosophy. Published papers with a philosophical character like "What is a particle?" Operates on several levels. Interesting guy. Shows, in effect, the philosophical ingredient that the string program (for all its mathematical brilliance) was lacking.
Of course hubris and arrogance can work both ways. Somebody should have reminded Clemenceau of the example of Julius Caesar, who could operate both as general and as politician (maybe even better as a politician). And I think of Galileo---the experimenter + philosopher--who led a revolution (who else could have!)
My thoughts are more confused than yours right now, and I'm sleepy. I have no clear orderly conclusions. Just have to stop.
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Re: The big bang
by newyear on October 18th, 2010, 12:54 pm
beef2jerky wrote:Scientist view the big bang as the beginning of time, seeing as space and time are proclaimed to be one by these same scientists. However, if there is no time, how can there be any movement? If the matter was expanding and collapsing on itself, there must have been some form of ultimate time beyond the time of our universe to record it. If there was no time, then no movement would be possible, is it not so? So either the big bang theory is false, IMO, or it proves the existence of a higher level of time beyond our universe.
The Fabric of the Cosmos by Brian Greene (Penguin) may be interesting reading. The general conclusion is that scientists (physicists) just don't know what happened. What can be said is that time started when the first indication of something actually happened. For example, the creation of something like space. Nothing can exist without a place (space) for it to happen.
It can be observed that when scientists come up against a brick wall (like that of going back in time to the very beginning), some of their theories do seem more philosophical than scientific. The Higgs boson, for example. This is human nature, isn't it? Without an idea that may be unscientific, a scientific conclusion cannot even be contemplated.
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Re: The big bang
by xris on October 18th, 2010, 1:36 pm
I think we bash our brains out with the idea of a before and a begining, in the space, this time. If there was no before, what constitutes as a begining? if you have no before you have no visible start date to recommend. I love the question how long is a piece of string? twice as long as half of it..We cant have it both ways, a begining and nothing, its not logical. If infinity is a mirage then time is also. I think relativity does indicate that time is a relative to our observation, our observation is sadly confused and tied to our experience of time. We dont fully appreciate its full potential to explain the truth. When E is infinite what does that do to time?Or if time is limitless what does that make M...
As an ignoramus on the science of this subject most of these links kindly provided are pure gibberish to me..Could someone explain for instance this..there is no such dynamic space time in nature...Thanks xris..
As an ignoramus on the science of this subject most of these links kindly provided are pure gibberish to me..Could someone explain for instance this..there is no such dynamic space time in nature...Thanks xris..
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Re: The big bang
by xris on October 18th, 2010, 2:18 pm
Im interested in why you dont think infinity is important in cosmology. Does that infer that you believe infinity is not a possibility? or it is and whatever your answer, surely that is significant to cosmology.Marshall wrote:xris wrote:I think we all have problems with certain concepts..Originality, infinity , nothing and the very idea of time. The Big Bang combines all those difficult concepts and becomes more elusive, the more we speculate. I am only glad we have such mysteries, how boring would life be without them.
Speak for yourself Xris, as regards "originality, infinity, nothing". I don't think those concepts are important in cosmology, or in the philosophy of cosmology. If you find them intriguing you can start at thread about them in some other forum.
Time is certainly an important concept. The question I would ask you is do you want to familiarize yourself with contemporary ideas of the nature of time?
Foundational Questions Institute had an essay contest on the nature of time, in 2008. They arranged to have two panels of judges and two sets of prizes. So in particular there were two First Prize essays. If you want, you can read both essays and choose your favorite :-D. I liked both.
Here are links to the two first prize essays:
Rovelli's "Forget Time" http://arxiv.org/abs/0903.3832
Barbour's "The Nature of Time" http://arxiv.org/abs/0903.3489
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Re: The big bang
by Marshall on October 18th, 2010, 2:25 pm
newyear wrote:...
The Fabric of the Cosmos by Brian Greene (Penguin) may be interesting reading...
Out of date. Consensus has been shifting at least since 2005. Greene is a good writer and popularizer, but has not produced much important research---no recent highly cited papers.
My advice would be to forget about anything written before 2005, and watch the BBC program.
Greene will bring out a new book in the spring of 2011. My guess is it will present some of these before-bang models. He's not a highly regarded authority (there will be other books by people more in the front line) but if you like his writing style then try reading the new Greene book when it comes out.
Of course "nobody knows", stuff has to be tested and retested. The interesting thing, which a growing number of researchers are interested in, is what are the different models, what do they predict about observable phenomena, how can they be tested, how much fine-tuning do they require (or conversely, how robust and un-finicky are they.) Models that are not fragile tend to attract support---ones that when you simulate the universe in a computer they tend to work pretty much whatever numbers you throw at them---don't break down easily or require fine tuning the input numbers.
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Re: The big bang
by Marshall on October 18th, 2010, 2:33 pm
xris wrote:..Im interested in why you dont think infinity is important in cosmology. Does that infer that you believe infinity is not a possibility? or it is and whatever your answer, surely that is significant to cosmology.
Infinity is not interesting because it is a routine concept, like the number 2, or zero, or pi. It is not important to talk about it in cosmology, and people don't. I read professional research in cosmology and people do not discuss about the topic of "infinity". Some things are finite and some are not. It's taken for granted.
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Re: The big bang
by xris on October 18th, 2010, 2:52 pm
Marshall wrote:xris wrote:..Im interested in why you dont think infinity is important in cosmology. Does that infer that you believe infinity is not a possibility? or it is and whatever your answer, surely that is significant to cosmology.
Infinity is not interesting because it is a routine concept, like the number 2, or zero, or pi. It is not important to talk about it in cosmology, and people don't. I read professional research in cosmology and people do not discuss about the topic of "infinity". Some things are finite and some are not. It's taken for granted.
Sorry but I find the idea that infinity is accepted as a fact in cosmology as strange concept. It implies infinite matter ...when it is so apparently, is not. Maybe I have the completely wrong idea on what cosmologists consider as important.
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Re: The big bang
by Lincoln on October 18th, 2010, 4:37 pm
Marshall wrote: He's not a highly regarded authority (there will be other books by people more in the front line)
Sometimes you're a snob Marshall. The gift of communication and the gift of testing the boundaries are not often both given to the same individual. I know some very incoherent smart people and some people who are smart enough to understand >>and<< be able to translate. Both skill sets are valuable.
I object to the self-perpetuating process of someone getting a best seller, so subsequent publishers and multimedia types go back to the author, thereby elevating their visibility, in a frenzied spiral, until theirs is the only voice heard in the public media. But I don't insist that the errant genius actually write my popularizations.
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Lincoln - Resident Member
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Re: The big bang
by Marshall on October 18th, 2010, 5:51 pm
Lincoln wrote:Marshall wrote: He's not a highly regarded authority (there will be other books by people more in the front line)
Sometimes you're a snob Marshall. The gift of communication and the gift of testing the boundaries are not often both given to the same individual. ... Both skill sets are valuable.
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Heh heh, I don't think either of us is a snob, Lincoln. I admire and value Greene as a talented popularizer. He has a great way with language, charm. He organizes science fairs, inspires young people.
I highly respect people's communication skills, and he is obviously a star.
But the commercial BLURBS for his books, as I recall, portray him as a leading this or that. His actual scientific output is not that great. I think you know what I mean and acknowledge it in what you say---probably know even better than I that as a theorist Greene is minor.
I don't see him in the list of highly cited string papers, or any kind of highly cited research publication. I follow arxiv hep-th fairly regularly and don't see him publishing much of anything these days. I don't see him giving plenary talks at the annual Strings conference.
Like you say, two separate skill-sets!
But just because I say this doesn't mean you have to DEFEND Greene. I am not being mean to him :-D. It is just how things are. I think we both acknowledge it.
Also the string theorists who actually ARE tops, those I've seen, should not be characterized as weird or "different" or poor communicators. The ones I've seen video (or live) are well-spoken and also good communicators (at a science level). I was impressed by the good clear talks , and panel discussion from Andy Strominger (one I most admire), Juan Maldacena, Eva Silverstein, Lisa Randall, R. Bousso...
Any one would be a pleasure to meet and converse with, they just don't write books that inspire highschool students with metaphors and imagery, they work a different crowd.
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