gib65

Since GR says that space-time is curved in the vicinity of matter, does this not mean that there's something there is space? This would be quite different from the classical view of space which is that it's... well... "space" - a big fat field of nothingness. But space-time curvability (is that word?) must mean there's something there to be curved, like the idea of the ether. Is this what modern scientists believe? Gib

Since GR says that space-time is curved in the vicinity of matter, does this not mean that there's something there is space? This would be quite different from the classical view of space which is that it's... well... "space" - a big fat field of nothingness. But space-time curvability (is that word?) must mean there's something there to be curved, like the idea of the ether. Is this what modern scientists believe? Gib

Have there ever been any studies that show a distinction between conditioning a behavior and conditioning the rate of CHANGE of a behavior? For example, let's say I had a rat that I wanted to press a leaver every 10 minutes or so, and I only reinforced it once for every leaver press so long as it's been ten minutes since the last reinforced leaver press. And let's say there was another rat that, for every leaver press, I wanted it to do so sooner than the time between its last two leaver presses, thereby increasing its leaver pressing frequency over time. Have there ever been any experiments to show that it is possible to control which one of these two kinds of conditioning one would want to apply? Gib

Have there ever been any studies that show a distinction between conditioning a behavior and conditioning the rate of CHANGE of a behavior? For example, let's say I had a rat that I wanted to press a leaver every 10 minutes or so, and I only reinforced it once for every leaver press so long as it's been ten minutes since the last reinforced leaver press. And let's say there was another rat that, for every leaver press, I wanted it to do so sooner than the time between its last two leaver presses, thereby increasing its leaver pressing frequency over time. Have there ever been any experiments to show that it is possible to control which one of these two kinds of conditioning one would want to apply? Gib

No it doesn't. And that's part of the reason I'm asking. See, I've always had a nagging suspision that our quest to find the foundations of consciousness has been leading us down the wrong road so long as we've been assuming that the brain is responsible for "producing" consciousness. What if, instead, the brain only ALLOWED for consciousness? (the old "correlation-not-causation" argument). But who knows, I could be wrong (hence the questioning). There is research supporting the existence of engrams, a type of neurological circuit predicted by Karl Lashley which can be thought of as a neural pathway that forms a feedback loop with itself. When stimulated, this loop keeps exciting itself thereby "keeping a thought in consciousness". This is very much like the flip-flop, the basic hardware piece in almost all computers responsible for memory (it stores exactly 1 bit). As for knowledge, most things that we feel we know correspond to fixed neural pathways that have been established over time such that it is unlikely for a signal to deviate from it. Come to think of it, when you talk about memory and knowledge, aren't they the same thing. I mean, if you remember something, you know it, and if you know it, you remember it. So whatever physical explanation you have to explain the one, it could be adequate to explain the other. But all this is only insofar as I know, and I'm no expert.

No it doesn't. And that's part of the reason I'm asking. See, I've always had a nagging suspision that our quest to find the foundations of consciousness has been leading us down the wrong road so long as we've been assuming that the brain is responsible for "producing" consciousness. What if, instead, the brain only ALLOWED for consciousness? (the old "correlation-not-causation" argument). But who knows, I could be wrong (hence the questioning). There is research supporting the existence of engrams, a type of neurological circuit predicted by Karl Lashley which can be thought of as a neural pathway that forms a feedback loop with itself. When stimulated, this loop keeps exciting itself thereby "keeping a thought in consciousness". This is very much like the flip-flop, the basic hardware piece in almost all computers responsible for memory (it stores exactly 1 bit). As for knowledge, most things that we feel we know correspond to fixed neural pathways that have been established over time such that it is unlikely for a signal to deviate from it. Come to think of it, when you talk about memory and knowledge, aren't they the same thing. I mean, if you remember something, you know it, and if you know it, you remember it. So whatever physical explanation you have to explain the one, it could be adequate to explain the other. But all this is only insofar as I know, and I'm no expert.

Ah, but, this gets at the the first interpretation I mentioned above. That is, we may not know how to build AI or cure all known brain diseases, but we can still say that the brain is basically an organic computer and and it works by transmitting electric signals along axons and chemical signals across synaptic gaps. What I'm asking is, can we say that we KNOW that this is how the brain works, or are there aspects/parts of the brain that this model simply does not work with.

Ah, but, this gets at the the first interpretation I mentioned above. That is, we may not know how to build AI or cure all known brain diseases, but we can still say that the brain is basically an organic computer and and it works by transmitting electric signals along axons and chemical signals across synaptic gaps. What I'm asking is, can we say that we KNOW that this is how the brain works, or are there aspects/parts of the brain that this model simply does not work with.

I've taken a brain anatomy course in university and it sounds to me like neurologists have pretty much figured out how the brain works. Electrical signals enter the brain from the senses, travel along the axons of neurons, communicate with neighbouring neurons by releasing neurotransmitters across the synaptic gap which then get converted back to electric signals, and so on, until the brain transfers this signal to other bodily organs. It seems like a pretty deterministic and self-contained system that doesn't really leave any mysteries unresolved. I've also taken a few computer science courses (got my B.Sc in it) and the similarities between computer circuits and neurological circuits are uncanny to the point that if you can understand how a computer works, that understanding can be applied to the brain with little misrepresentation (more-or-less). So I was just wondering: is this all there is to it? I mean, I'd expect that the exact nature of a neuron is a little bit more complicated than being a conductor, and there might be mysteries to them that to date stump the neuroscientific community, but from what I understand these mysteries (if they exist) shouldn't change how we currently understand the brain to work (i.e. as an organic computer). Or are there greater mysteries to the effect that, until we solve them, we actually CANNOT say that we understand how the brain works (that is, there is NO theory to date that satisfactorily explains everything about the brain). Gib

I've taken a brain anatomy course in university and it sounds to me like neurologists have pretty much figured out how the brain works. Electrical signals enter the brain from the senses, travel along the axons of neurons, communicate with neighbouring neurons by releasing neurotransmitters across the synaptic gap which then get converted back to electric signals, and so on, until the brain transfers this signal to other bodily organs. It seems like a pretty deterministic and self-contained system that doesn't really leave any mysteries unresolved. I've also taken a few computer science courses (got my B.Sc in it) and the similarities between computer circuits and neurological circuits are uncanny to the point that if you can understand how a computer works, that understanding can be applied to the brain with little misrepresentation (more-or-less). So I was just wondering: is this all there is to it? I mean, I'd expect that the exact nature of a neuron is a little bit more complicated than being a conductor, and there might be mysteries to them that to date stump the neuroscientific community, but from what I understand these mysteries (if they exist) shouldn't change how we currently understand the brain to work (i.e. as an organic computer). Or are there greater mysteries to the effect that, until we solve them, we actually CANNOT say that we understand how the brain works (that is, there is NO theory to date that satisfactorily explains everything about the brain). Gib

That's interesting stuff. I'd really like to understand better. How exactly is GR and the theory of gravitons equivalent? Does it require extensive mathematics to understand? Is there a relatively simple way to explain it?

And another thing: How does Einsteins general theory of relativity fit into all this? It seems to me that gravitons and the warping of space-time are not quite the same theory. Are they simply different expressions for the same idea, are they mutually exclusive, or are they different theories but capable of coexisting as valid explanations for gravity?

According to this, might it be possible (hypothetically) for two bodies who are in the process of exchanging gravitons, to be so far apart that they run out of gravitons to exchange before they collide? Suppose their masses were incredibly different from each other so that the larger one emits gravitons at such a high rate that, even though the smaller one is trying to compensate by exchanging gravitons at as high a rate as it possibly can, it could not possibly keep supplying the larger one with the gravitons it needs to replenish its stock. Is it possible that the larger one could actually run out?

I've been reading a paper by someone who thinks gravity violates the law of conservation of energy, and I can't quite find the flaw in his reasoning. He says that because the pulling force of gravity never ceases and that it doesn't seem to get the energy to apply this pulling force from anywhere external to itself, it represents a source of contiuously generated energy that comes out of nothing. It would be analogous to someone spinning a rock tied to a string around in circles forever without ever consuming energy in anyway in order to keep up the energy required to spin this rock. I've often wondered about this myself. When I took physics in my first year at university, I asked my professor about this apearant paradox between gravity and the law of conservation of energy. He spouted off the same argument I heard before about potential energy. That is, in order for something to exhaust kinetic energy when falling under the influence of gravity, it must have consumed energy in order to be lifted to the level from which it fell. At that level it stores this energy as potential, and when it falls it gets converted to kinetic. Thus no energy is introduced from a void, it is only converted from one form to another. This argument can be applied to similar phenomena such as swinging pendulums and the orbit of bodies around more massive bodies. I understand this, but there are other thought experiments that I've done that can't be explained by this reasoning. One, for instance, is when you have a small body floating along in space far, far away from any massive body exerting gravitational influence. albeit if the small body and larger body both coexist in the same universe, they would have to exert SOME gravitational influence on each other, but let's just say this influence is minute since they are so far apart. Now, suppose the smaller body is in motion towards the larger body, and although not under its gravitational influence by that much, it will become more and more influenced as it gets closer. And as it gets closer it begins to speed up. Eventually it will be close enough for its velocity to be markedly much more than it used to be when it was extremely far away. Now, I suppose that one could explain the seemingly spontaneous introduction of more and more kinetic energy into the smaller body as really just a gradual transformation of potential energy into kinetic energy, but that presupposes that the small body had this potential energy from the very begining. Well, maybe it did. But then where did it get THAT energy from? Furthermore, what do we say about another small body travelling with the same initial velocity in the same direction, but starting from further away? By the time it gets to the larger body, it should be travelling even faster than the first small body. Do we just say it had MORE potential energy initially than the first small body? Ultimately, there is no end to how much potential energy we could presume existed in any body's initial state in order to make up for the appearance of kinetic energy once it falls under the influence of gravity. It just seems too ad hoc to me. I'm sure there is a reasonable explanation to my inquiry. Can anyone explain this?

OK, so let me get this straight: time slows down for both observers when travelling uniformly, but then all of a sudden time speeds up for the stay-at-home when the traveller suddenly turns around (effectively accelerating). For the whole while that the traveller is accelerating, the stay-at-home ages rapidly enough to surpass the amount of time that the traveller has experienced, plus enough extra to resume aging slowly upon the travellers ride home at uniform velocity to still be older by the time they both reunite. Is this correct? In order for this to work out, I presume that the farther away the traveller has gone before accelerating to return home, the faster the stay-at-home will have to age. This follows because the act of accelerating in order to turn around and head home takes the same amount of time to complete regardless of how far the traveller has gone before doing this. But if the gap between their ages keeps getting wider as the traveller moves at uniform velocity (in either direction), then the amount of aging the stay-at-home has to "catch-up" on depends on how long/far the traveller has been travelling. Therefore, if the act of accelerating to return home takes constant time, then the RATE at which the stay-at-home will have to age during this act cannot be constant. Have I got this right? Essentially, what this boils down to is that in a gravitational field, the rate at which time slows down is directly proportional to the depth with which you are in the gravitational field. Is this right? This also means that when the stay-at-home begins to increase his rate of aging (when the traveller turns around) the rate change is a discontinuous jump. That is, relative to the traveller before he turns around, the stay-at-home's rate of aging is slow, but since the act of accelerating begins instantaneously, the gravitational field that suddenly appears (in the context of GR) is also instantaneous, and the difference between the traveller's and the stay-at-home's depth within this field likewise appears instantaneously. Therefore, the rate of aging for the stay-at-home must make an instantaneous leap from slow to fast (relative to the traveller). Is this what happens?

Yes, that's what I mean to say

Does anybody have a tri-brow? I do! I've got a little tuff of hair between my eyebrows, yet it is discontinuous with either.

I was just wondering this, because in all my contemplating about velocity and special relativity, I tend to get confused as to what physical attributes of objects get affected in what way. That is, when an object speeds up, does it's mass increase or decrease, does its length increase or decrease. Know exactly what way each attribute changes would surely resolve a lot of pseudo-paradoxes that I arrive at when I try (my damnedest) to visualize such scenarios. I also get confused when trying to remember in what way these attributes change depending on whether I'm talking about the observer or the observed, or the traveler or the stay-at-home. Also, in what way does the DIRECTION effect these attribute changes (i.e. if spacepod A travels at 0.99c in one direction and another spacepod B travels at 0.99c in the opposite direction, do their atributes such as rate of time, mass, length, etc. change in the same direction or opposite directions). So basically, I'm asking: 1) What are all the attributes that change? 2) In what direction do they change as a function of velocity? 3) What are the differences between the changes for the observers vs. the observed - and/or - the traveler vs. the stay-at-home? Does anyone know?

Well, I know enough about the speed of light to know that it does not matter how fast the object that emits the light is going, light always travels at 300,000 km/s in a vacuum relative to the observer. So even if one observer, traveling at 0.9c in one direction, is traveling away from another observer traveling at 0.9c in the opposite direction (both relative to a stationary object as lightSword pointed out), light emitted from one observer would still catch up to the other observer, and it would take (300,000 x L) seconds (where L is the distance between the two observers when the light was emitted). Now, you make think that this means the light is violating the universal speed limit of 300,000 km/s, but remember when this speed limit is applied to light, it must be applied in the context of the speed relative to the observer since, unlike material objects, the speed of light has no relative speed except to the observer.

oooooh

There's something I've always wonder about general relativity and what it has to say about the workings of physical laws. Here's a scenario: You're sitting in a space pod and you push on the engine throttle cause the pod to accelerate forward. You feel the force of acceleration pushing you back against your seat. Now what general relativity says about this scenario is that you can look at it two ways: 1) that the pod is accelerating forward and it is the forward moving force of the seat against your back that you feel, or 2) that there is a gravitational field behind you and all objects of the universe fall under its influence, except you and your pod because the force of the rockets keep you in place. So here's my question: How does general relativity explain the spontaneous existence of such a gravitational field, especially when there's no mass to sustain it? It would have to say that by pushing the engine throttle, not only do you egnite the engines, but you CAUSE a gravitational field to pop into existence. In other words, the laws of physics themselves would be subject to relativity (that is, what kind of physical laws exist in the universe is relative to your persective). What does GR say about this? Gib

Woaw! Lots of information. Thanks to Teotihuacan and badchad for their lengthy and very informative posts. Also, to all others who posted links to other sites.

We've all heard the warnings: do to many drugs and you'll end up like Ozzy, permanently brain damaged. But I've done a bit of research when I was doing my psych degree and I found it extremely hard to find the studies that explain the exact details of how drugs do this, what kind of damage they cause, how much is too much, what kind of drugs cause what kind of damage, and so forth and so on. I don't doubt that the evidence is out there, but I'd really like to come across some good ones. Does anyone have any knowledge to impart? Gibby

I don't see why it would be so hard to believe that there are biological differences to some degree. Afterall, there's clearly biological differences in general, so why not also in the brain. For one thing, I think it's reasonable to assume sexual attraction is hard wired. I guess you could argue that sexual attraction is learnt solely through societal upbringing, but this would require some extremely substantial evidence and it would be pretty astonishing if it turned out to be this way. I think one has to keep in mind a couple things on this subject: 1) differences are not a bad thing. The wider the variety in a species, the better off it is in adapting to situations of various kinds. There's absolutely no reasons to cast value judgements along a "good"/"bad" scale when comparing differences between people. 2) "Biological" does not mean "unchangeable" nor does it mean "generalizable". If, on average, women are more emotional than men, or men are more aggressive than women, there is absolutely no justification for randomly selecting a man or woman from society at large and saying that he/she is obviously aggressive/emotional simply because of the obvious fact that he/she is male/female. Furthermore, even if said random male/female so happens to fit the average profile, there is no reason to say they are destined to remain that way for the entirety of their lives. Environment can still have an untold effect and free will can still stretch natural predispositions to whatever lengths it has the power to do so with.

I see, makes sense. Thanks