Quote:
Originally Posted by Doctordick
There is one question I would like to ask Dr. Dennet regarding “Consciousness Explained”. Since he claims a supposed explanation of Consciousness, he should be able to answer any question regarding the presence or absence of consciousness. The question I have in mind is, “is one conscious when one is dreaming?” I think the answer to that question could be interesting.
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Why, what do you have in mind?
I personally wouldn't know what to answer, as it's kind of a matter of what one supposes "being conscious" means.
But, running with the idea that dreams are a product of the brain re-ordering information, and looking for new self-coherent connections between ideas (which would explain why in dreams there often exists rather strange combinations of ideas, why dreams often include things that have been in our mind recently, why we sometimes come up with a solution to a difficult problem in our dreams, and why good night sleep seems to aid learning), then I think it's to be expected that sometimes that ordering doesn't include the idea of "self" at all, and thus cannot really be remembered later (it's not "something that happened to me"), and can't really be considered a conscious experience.
On the other hand, maybe one doesn't want to call those instances "dreams" at all, in which case a dream is always something consciously experienced.
Of course I understand some people associated "being conscious" with the everyday idea of being awake...
Anyway, I read the simultaneity stuff from the OP and didn't spot any errors. Albeit I did read it little bit less carefully than the rest, because that relationship between the definition of simultaneity and geometry seems fairly obvious to me.
Quote:
Originally Posted by Doctordick
At this point, it is very important to examine the reverse case...
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...Thus it is that he will hold forth that his clock is correct and the (so called) rest clock appears to be contracted by exactly the standard Lorentz contraction. The only reason I went through that, was because many people have difficulty comprehending how the moving observer (who' entire perspective appears to be Lorentz contracted) can see the rest observer as Lorentz contracted. (I strongly suspect that many trained physicists can't see it either; they are just throughly indoctrinated in conventional relativity. But that is only an opinion  ) |
Well I have not heard any physicist talking about that relationship explicitly either, but then where would I...? The dumbed down presentations are so silly they make my head hurt, and I always end up thinking "someone needs to be fired for this..."
Incidentally, as I'm writing this there's a History Channel program "The Universe" on, and it's an episode about space travel. They are bringing up the speed limit of light speed as per relativity, and sure enough, they have once again dumbed it down so much as to make completely false assertions. Here's a direct 1:1 quote straight from Mr. Neil deGrasse Tyson (PhD in Astrophysics)
"Light's fast, but the universe is huge. So even if we could ride on a beam of light, if we wanted to cross the galaxy - the way they do it on the science fiction programs - it would take a hundred thousand years to do it".
And the narrator continues:
"And even at light speed, traveling to the nearest galaxy, would take several million years"
And then of course they had a computer animation where "a beam of light" is travelling "really fast through space"...
It is really really really beyond me, how any self-respecting scientist - who supposedly understand what relativistic speed limit means - can spew something like that from their mouth... Is it possible, that some of them don't really understand what it means? That they just heard somewhere that C is the speed limit and run that against their newtonian worldview without understanding what it means and where it comes from? Because if they understood it, surely they'd see it doesn't really play down the way they talk about it... Is that it? I'm quite puzzled. And to be honest, a bit annoyed.
How common is that misconception then? How many people reading this thinks what they are saying is valid, according to relativity? And why?
Well, then they go on to talk about space warps in terms of static spacetime, and about tachyons in a really stupid and incoherent manner (They seem to think tachyon simply refers to an "infinitely fast" object or something). I can't go on because I'm getting too depressed over that, so back to the topic
The only reason I find that relationship between simultaneity and geometry so obvious is because I understood it myself via visualizing Lorentz-transformation in my head. I have ran into many people who "know" relativity but did not understand it enough to see that relationship for some reason. I suspected it was just because they were somewhat casually interested of the subject and had never thought about it much.
At any rate, it should be quite obvious that if you set about to measure the length of a box, you are measuring "where the extends of the box are simultaneously". Change your idea of simultaneity, and you change your idea of the geometry of the box.
Anyway, let me walk through the final part of the OP still, maybe we'll uncover some typos...
Quote:
Originally Posted by Doctordick
Finally, in order for the moving observer to measure the period of the rest clock, he must receive two signals...
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Again, as all velocities along our displacement vectors are v ?, d 1+d 2=S. It follows that, from the perspective of our rest frame, this is exactly  |
Yup
Quote:
or, solving for S,
 .
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While I was able to understand that that expressions is true, I do not know what the algebraic steps are in between there. It's just once again my unfamiliarity with math, I'm sure it's something really simple :P
Yup.
I'll continue from here soon...
-Anssi
