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post #121 of 6198
Actually Horton would be more like our place in a universe of universes, assuming there is such a thing, and if there is that it can possibly have any effect on us in ours. In our own Universe, we can see a long, long way. We can't see to the edge, because light hasn't had time to come to us from more than about 15 billion light years out. But, we can see more or less a sphere with a radius of 15 billion light years, and that's a huge space. Within that space, physics seems to work exactly everywhere as it works here. As is always the case in a system that's young, energy consumption was profligate back in the early days, but basic physics shows no changes back 15 billion years from now.

In general, I'd always make a distinction between knowing more facts, and figure out things that have any practical impact on us. Discovering that there are an infinite number of other universes that we can never get to would be amazing but completely useless in terms of making us better, faster, richer, smarter, etc... And it wouldn't do a thing to change the physics of this universe that we are stuck in, and therefore which rule our lives and set limits on us.
post #122 of 6198
Quote:


Originally posted by Gus

We don't even know what's on the surface of Mars!
Come to think of it, we haven't even figured out how our own minds work.

Gus,

Ahhh, yes, we do know what's on the surface of Mars. Almost 30 years ago the Viking lander took pictures, analyzed soil, etc. There have been probes since, Soviet and U.S. Another recent lander was Sojourer, and Beagle is next.

Our point, which Dean clarified and I will further, is that the 80% number I pulled from my rectum is MAYBE how much of physics we have down cold. Physics includes mechanics, thermo, electricity and magnetism, optics, nuclear, particle, condensed matter, plasma, etc. I'm not counting the 'stretched' parts of physics like bio-, nano-, etc.

Here's an analogy. People are exploring the world. At some point 500 years ago, Europeans 'discovered' America. At that point, it was clearly known very well how big the earth was, and what kind of geology and flora and fauna existed on the earth. There was still more to explore, more to do, but no one who had done the homework would have expected to sail off the edge of the world, or find another 5 continents between asia and america with mountains 20miles high and seas of liquid mercury or gigantic flying dragons. It just wasn't gonna happen.

I'm not saying we know where the end of physics is that well. But believe me, the physicists I've talked to (and I'm not one btw) say that the majority is over, and they say it with a heavy sigh of nostalgia and disappointment. They would like nothing better than to be part of the next big thing in physics, but lots of really smart people have been trying to find it for a long time. Unfortunately, a lot of what's out there is cleanup work from the big discoveries of the late 19th and early 20th century. Again, I'm just talking physics, but 'just physics' underpins essentially all of the physical and natural sciences and engineering.

I said it wasn't popular. But imagine if it's true. We've been alive at THE MOMENT, practically an instant in history, where a great awakening took place in our understading of nature. Yes, some of us were watching Beevis and Butt-head part of that time, but it's heady nonetheless.

M
post #123 of 6198
Heh, heh... he said rectum, heh, heh.
post #124 of 6198
Dean, you keep emphasizing what is "practical".
Of course we cannot fathom how to put into practice what has not yet been discovered. Any more than the ancients would have any conception of what is practical with most of what we know today.

Moore said:
Quote:


"What would the new screenplay be? That E=mc^3? F=m/a? It simply doesn't work"

Your great, great, great (to the tenth power) grandfather, Aristotle Moore, said:
Quote:


"But Mr. Copernicus, what would the new parchment be? That the earth revolves around the sun? It simply doesn't work."

You think my analogy is false because the ancients were unaware of the physical truths (which were to be discovered in "the late 19th and early 20th century").
However, you've both left the door open (and a rather large door at that) to extraterrestrial intelligence. Of course you would say that they will have discovered the same physical truths because there can be no other. But how can you be so certain of that? They may have evolved in a way that is simply inconceivable to us. And that is even if evolution is applicable and we don't even know that. Who's to say what they may have discovered? Can you both keep a straight face and tell me that it cannot be anything fundamentally more or fundamentally different than what was learned on Earth in that period of one lousy century?

moore said:
Quote:


And it's only a testable hypothesis to the extent that we can look back in another 100 years and know, but that's the realm in which this discussion exists.

Did I miss something? When was that parameter established? If we look only 100 years beyond Sir Isaac Newton then we wouldn't yet see how relativity "radicalized" his thinking. No, that took 250 years.

However in the "realm" I'm trying to describe, they're both just a microsecond.
post #125 of 6198
Quote:


Originally posted by RobertWood
However, you've both left the door open (and a rather large door at that) to extraterrestrial intelligence. Of course you would say that they will have discovered the same physical truths because there can be no other. But how can you be so certain of that? They may have evolved in a way that is simply inconceivable to us. And that is even if evolution is applicable and we don't even know that. Who's to say what they may have discovered? Can you both keep a straight face and tell me that it cannot be anything fundamentally more or fundamentally different than what was learned on Earth in that period of one lousy century?

Hey! That was no lousy century. And if you stretch it to the period from the enlightenment to today, it's close to 500 years, which I'll grant were filled with discovery. It's just that I think we're on the other side of the peak where physics is concerned, and we won't just overturn all that knowledge because we find something newer and better. It's all refinements and applications at this point (with physics at least).

But, yes, I can keep a straight face and say that 1) we're extremely unlikely to find something that completely contradicts what physics we've learned here on earth, at least in a place we could hope to exist (in which case discussion is pointless, like Dean said with the parallel universes). It's not like we go to the Andromeda galaxy and all of the sudden the less force you apply to something the slower it accelerates. Like is 2+2 going to equal -1 there?

2) Regarding evolution, sure it could be radically different or not applicable, but that's biology. The physics will be theirs to discover, same as us. They certainly may have some new twists on interpretation we haven't thought of and definitely will apply it in interesting ways, but E will still = mc^2.

Quote:



But how can you be so certain of that?



Because the sun rises every day, things I drop fall down, hot things get colder, etc. Carl Sagan actually does a nice job of answering this question in a way more eloquent style than me in his last book "A Candle in the Dark". Highly recommended read. Part of his discussion in the one chapter is that science doesn't simply discard old theories. It takes them, keeps the parts that work, and modifies the rest to better fit the facts. We do this to better predict physical behavior.

Aristotle was the opposite of a scientist, and no relation 'a mine. He didn't believe in experiments and observation. The difference from even Galileo's time until now is that the line between science and mysticism is very clear now, and the dogmatists aren't in control. The burden of proof is on anyone defending any theory, and it has made science an incredibly strong, very useful tool.

M
post #126 of 6198
Quote:


Originally posted by Dean Roddey
You probably missed the point, though we made it a couple of times..


Oh, I didn't miss the point at all, I was just trying to create controversy.

Quote:


But within the narrow target that was being discussed, it is quite possible that we are 80% there. Some scientists, who are not egotistical idiots and not given to hyperbole, think that's quite possible. The fact of the 'matter' (pun intended) is that the fundamental nature of matter is probably not a bottomless pit with endless doors to open. The ramifications of the things that we learn on the way to the last door can go on and on and on, but that doesn't mean that the doors keep opening downward, just outward.

This is where I disagree. I'm not implying that these scientists are idiots, I'm just saying I don't buy it. How can you quantify what you don't know? You could very easily be wrong about what you don't know.

Moore,

No, we don't know whats on the surface of Mars. We have a VERY BASIC understanding of it. We don't even know how much ( if any) water there is. Some scientists say there are vast oceans, others say there is "just a little". That sounds to me like we just DON'T KNOW.

Gus
post #127 of 6198
Quote:


Carl Sagan actually does a nice job of answering this question in a way more eloquent style than me

I'm not so sure of that. Not after reading your last post!

And I get the feeling that you you tossed that all out off the top of your head.
Hell, it took me all night to come up with the new "parchment" quip.
post #128 of 6198
How about what Gus has pointed out? We have only a rudimentary understanding of just Mars. And that understanding is so thin that it seems to change almost on a daily basis.
Go beyond Mars and it becomes like a blind man shooting in the dark.
Let me see if I understand this. Simply because we can squint real hard and just barely identify and measure light waves that come from 15 billion light years out, that nothing can or will ever fundamentally alter this Gospel of Physics we have constructed? Not in a million years? Not in a billion years?

I go back to Dean's comment that "isn't it convenient that UFO reports of aliens coincide with 1950's movie images"?

Well isn't it pretty "convenient" that what oh so very little we see now when our tools look 15 billion light years out, fits this Gospel of Physics we've created?
____________________________

Gospel: "anything propounded or accepted as infallibly true", "something, such as an idea or principle, accepted as unquestionably true". (Websters)
post #129 of 6198
Quote:


We don't even know how much ( if any) water there is. Some scientists say there are vast oceans, others say there is "just a little". That sounds to me like we just DON'T KNOW.

Actually, we kind of do. The latest results that have come back recently shows at least a Lake Michigan of frozen water just under the surface in the southern hemisphere :-)

But again, you are talking about something different from what we are. Whether there is water on the surface of Mars is like "What is in the hand you hold behind your back?". I don't know, but when I find out, its not going to fundamentally change our understanding of physics. Its an interesting issue related to the evolution of planets in our solar system of course, but not a fundamental discovery in the way that we are talking about.
post #130 of 6198
Quote:


Well isn't it pretty "convenient" that what oh so very little we see now when our tools look 15 billion light years out, fits this Gospel of Physics we've created?

Its not really convenient at all. There is no reason whatsoever to think that physics would be different in other parts of the universe. The rules of our physics were born in the big bang, and everything inside our universe was created in that original event, so it makes perfect sense that physics would be the same everywhere.

You have to keep in mind that the big bang was probably one of the simplest events of all time. All that was really created in the big bang, matter-wise, was hydrogen and a little helium, and some isotopes. All of the massively complex stuff that we see out there now has come from processing of hydrogen in stars. Its just many, many variations on the same process, working with the simplest of ingredients. Its only in its variation that it is difficult to understand, not because its mysteriously opaque to us. We've long known what the basic ingredients and rules are, its just a matter of figuring out all of the many ways that those basic ingredients and rules can be put together (and its a lot of ways obviously, with us being an example.)

Quote:


How about what Gus has pointed out? We have only a rudimentary understanding of just Mars. And that understanding is so thin that it seems to change almost on a daily basis.

But those are just new variations on a theme, not anything fundamentally new, from the perspective of an understanding of the raw physics of our universe.

The places where we are likely to learn really new stuff are far out of our reach for a long time, perhaps forever. Black holes and quarsars and such are the places where our physics is stretched to the limit, but there aren't any anywhere nearby, particularly quasars. The rest of the visible universe exists within a range of temperatures, pressures, and speeds, that fall well without our understanding of physics. There are other things out there that we don't fully understand, but those are just macro sized manifestions of the basic rules and ingredients. Its those variations that we have not catalogued and explained fully, not the fundamental processes that created them.
post #131 of 6198
I knew I'd regret not saying "multiverse(s). Now where did I leave my T.A.R.D.I.S.?

Howie
post #132 of 6198
Are we licked, boys?

I repeat. I'm not sure Sagan had anything on either of them when it comes to communicating this stuff. I've learned more about physics in a few of their short paragraphs than anything else I've ever read. And I read Sagan's first book (Cosmos).

Bob
post #133 of 6198
Dean,

I undestand fully, trust me. The point that I'm trying to make is not that our understanding ( or lack there-of) of the geology of nearby planets has anything to do with the basic laws of physics. That was just an example I used to put the state of our technology in context. The point is that how do we get the confidence to say we know so much when our capabilities are so humble. I recognize how far we have come in our understanding of the laws that govern the known universe, but there isn't a law that says that there arent 12 billion other laws that we still need to discover.

...and as for the water thing, I read the report too. The way it was presented, it sounded like an educated guess. The week following that report, they reported a very large green patch that they thought may be moss, but I don't hear any scientist saying they have found life on mars yet.

P.S.

I'm not arguing with you, most of your points are well taken, it's just i don't feel we are as advanced as you may think we are, and as far as the veracity of ALL the current theories of science, I keep and OPEN mind.

Gus
post #134 of 6198
Quote:


I recognize how far we have come in our understanding of the laws that govern the known universe, but there isn't a law that says that there arent 12 billion other laws that we still need to discover

In terms of the fundamentals, we are going the other way. We aren't trying to discover more laws, we are trying to discover fewer of them. The search for fundamental laws of energy and matter is mostly involved in finding simpler laws that cover more things, more generally. There are definitely billions (or A Sagan, billions and billions) of *facts* to discover, but fewer new laws. The laws will reduce, and include multiple previous disparate laws.

Things like 'suns blow up if they are too big' is a fact, not a law really. Laws (general speaking) in science are very fundamental, and there have never been a large number of them. Laws are things like thermodynamics or electrodynamics. They are very, very general.

Eventually, the goal is to have the Theory of Everything, which would be a simple law that describes all of the four forces, and how they fit together, and how that in turn manifests in the matter, energy and fields that exist. At that point, there would be only one law, and everything else would just be facts derived from that law.
post #135 of 6198
But don't we understand from reading Moore that the period of "enlightment" includes the time of Newton? Might Newton have said in his time... "we aren't trying to discover more laws, we are trying to discover fewer of them"?
And wouldn't that seem incongruous now (in light of the later discovery of relativity)? So how do we ever know at what point to make a statement like "we aren't trying to discover more laws, we are trying to discover fewer of them"?
post #136 of 6198
Quote:


But don't we understand from reading Moore that the period of "enlightment" includes the time of Newton? Might Newton have said in his time... "we aren't trying to discover more laws, we are trying to discover fewer of them"?

And wouldn't that seem incongruous now (in light of the later discovery of relativity)? So how do we ever know at what point to make a statement like "we aren't trying to discover more laws, we are trying to discover fewer of them"?

But Newton's laws were a reduction. It brought many previous ideas about how the world works under one theory of universal gravity that covered them all, more generally.

Relativity was a further reduction. It includes Newton's law but in a more general way that describes more phenoma more generally.

So neither of these created more laws. They replaced multiple, more complex, less explanatory laws into single, more inclusive, more fundamental laws, all on the way towards the ultimate goal of a single theory that describes the most fundamental attributes of matter and energy.
post #137 of 6198
Damn. I thought I had you there. Shoulda known better.
I'm reminded of that old lawyer axiom. Don't ask the witness a question unless you know what the answer is going to be.
post #138 of 6198
Are you buying that, Gus? That relativity can be characterized as a "reduction" even though it turned everything on it's head? Couldn't a few more "reductions" like that upset their original apple cart?

Or am I just prone to hyperbole? If it's the latter I can take it.
post #139 of 6198
Well, I buy it, in a certain way. Semantics is what we are caught in. I can agree with Dean, but still maintain my possition. I think Dean is too clever for us to debunk though Bob.

I maintain that of all the knowledge there is to be gained in all sciences including physiscs, we are only at the beginning. Of course I can't say that any of the existing fundamental laws of physics will be discarded as new ones are revealed ( which is quite possible, if you keep an open mind), but tons of useful knowledge of how matter and energy tick still await discovery.

Gus
post #140 of 6198
If it turns out that there are trillions of other Bob Wood's out there, all in other universes, that would wipe out practically all religions out there, except maybe Hinduism, or certain branches of it. It would cause every major book on philosophy to be re-written. It would be an epochal discovery. Let's say we knew 99.9 % of all physics. How de we know that the final 0.1 % isn't gonna be a doozy in its implications, both in philosophy and science? We don't know. But of course, even after all the workings of physics are carefully mapped out and understood, from the quantum to the galactic, there will still be scientific discovery and innovation. That's not going to stop.
post #141 of 6198
Amen
post #142 of 6198
So you see guys, we DON'T KNOW whats on the surface of Mars!!

http://www.popsci.com/popsci/aviatio...236202,00.html

Gus
post #143 of 6198
As much as Dean and Moore might want to believe otherwise, I think "DON'T KNOW" more aptly describes us than does "KNOW".

And by "us" I don't mean only Gus, Howie, Larry and Bob (and you too Mr. Spock and QQQ and anyone else I'm leaving out).
I mean all of us.
post #144 of 6198
The thing to understand about relativity is that it completely encapsulates Newtonian physics. It did not really invalidate anything of Newton. All it did is say that, in certain rare circumstances, of very high speed or very high gravity, Newton isn't completely correct. But Newtonian physics never claimed to address any such pathological circumstances. In the day to day world that we live in, and that send probes to the planets and sends the shuttle into orbit, Newtonian physics is completely correct, and its what is used. None of those folks are worried about relativity, because it only disagrees with Newton in extreme circumstances.

So all relatively did was encapsulate all of the day to day physics of Newton, but deal with a wider range of speeds and matter densities. It didn't 'overturn' Newton or anything like that. Its hard to call a theory overturned when its used infinitely more than the one that supposedly overturned it.

Relatively was a philosophical revolution of course, in that it gave a very different set of explanations for the effect that we call gravity. But in terms of getting practical things done, it really only differs under circumstances that none of us will ever experience (for the best in most cases.)

Quote:


If it turns out that there are trillions of other Bob Wood's out there

Some ideas are best left unexplored, for the good of man.
post #145 of 6198
As I was saying, maybe we do KNOW.
post #146 of 6198
Man, you guys have been busy! Where to start?

Quote:


Originally posted by Gus

This is where I disagree. I'm not implying that these scientists are idiots, I'm just saying I don't buy it. How can you quantify what you don't know? You could very easily be wrong about what you don't know.

Moore,

No, we don't know whats on the surface of Mars. We have a VERY BASIC understanding of it. We don't even know how much ( if any) water there is. Some scientists say there are vast oceans, others say there is "just a little". That sounds to me like we just DON'T KNOW.

Gus

I think we're at a semantic stalemate. We know that Mars is basically covered with rocks and dust. There's evidence for liquid flow in the past. Speculation but no real evidence of life, now or past. Good enough for me, the rest is just details. Was it water or CO2 or something else, and how much of those are left frozen above or below ground? I just don't find those last questions to be fundamental or fascinating. Geology is kind of a crapshoot, to be frank, compared to Physics. The more complex things are the harder they are to nail down, and it's hard to do Geology 'experiments' so it's a lot of observation. And what if they found living moss on mars? Cool, yeah, but in the end, not too mind blowing, is it?

M
post #147 of 6198
Moore,

Are you sincere when saying that the first ever discovery of life outside of the Earth would not be mind blowing? Or are you pulling our collective leg?
post #148 of 6198
I bow to your kind words, Robert, but not sure I deserve them.

Quote:


Originally posted by RobertWood
Let me see if I understand this.....

Well isn't it pretty "convenient" that what oh so very little we see now when our tools look 15 billion light years out, fits this Gospel of Physics we've created?
____________________________

Gospel: "anything propounded or accepted as infallibly true", "something, such as an idea or principle, accepted as unquestionably true". (Websters)

NONONONONONONO!!!! I'm suprised Dean didn't jump on this and stamp it out. Although I suspect you were trying to get a rise out of us. There is no Gospel of Physics. Physics, and science is a bag of tricks and ideas that seem to work. It's absolutely and unequivocally NOT treated as infallible or unquestionable. It would be the death of science if that were the case. You, and anyone, is welcome to step up to the plate, propose a new theory or radical change to an old idea (E=mc^3). The only deal is you gotta prove it, at least in some small way. You can do this one of two ways. You can use existing theory and something really rigid like logic and math to tie your new piece into the puzzle, maybe displacing the old if it fits 'better'. Or you can do an experiment / make an observation that proves the point.

It happens all the time. There was this Podlenktov (sp?) gravity shield thing. You spin a superconducting coil and it will reduce the mass of anything over it by up to 2%, so they said. NASA bit, and a few others. Most physicists just shrugged and pointed out how badly such an idea fits what we know, and said it was unlikely to work. No one branded the guy a heretic. It's not that it didn't fit some dogmatic world view, it's just like your doing a jigsaw puzzle and someone comes to you with a ham sandwich and says 'here, let me stick this in one of those spots'. To date no one has reproduced or verified the gravity shield, which should have been a cinch if it worked as advertised.

A different example is Stan Pruisner. Over twenty years ago he had this crazy notion that proteins alone could cause some diseases, with no virus or bacteria. Prominent virologists didn't think so, it didn't seem fit with their ideas. Well, he demonstrated very clearly that he was right, and the ideas caught on and refined the old way of thinking. His work had such impact that he won the Nobel Prize in Medicine a few years back.

This is why the things we observe 'conveniently' fit science's paradigms so well. The models that don't fit are chucked or fixed, and the models that do become trusted. But never revered, never gospel. Anyone is welcome to take a crack.

M
post #149 of 6198
Moore,
If they found living moss on Mars it would be way more than just cool to me. It would be the smoking gun evidence of extraterrestrial life and certainly a most important event of my lifetime. And it would be a historic occasion for all of mankind too I think.

___________________________________________
"How can you quantify what you don't know? You could very easily be
wrong about what you don't know."
______________________________________

A most elequent statement made by Gus I think and lacking very little room for argument.
post #150 of 6198
Quote:


"...but not sure I deserve them"

Hors****t. No one ever explained science in a better way than you just did. Where was your textbook when I was in high school? It might have given many of us an early appreciation of science that we never had.

p.s. but you did not address my last post

p.p.s and I agree wholeheartedly with what RVonse just said about what Gus said. How can we (or I should say you) possibly argue with that?
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