Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Q and A on 03/02/2004 04:41:57
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Hi guys,
I'm a little new to this Physics game, but it really interests me. I have a few questions I was hoping you all could help me out with.
--First off is time. It seems that the majority of the science world assumes that there is such a thing as a snapshot of time. What's some of your views on this? Can you take an Instant from something that is Infinite? It seems to me that say, i.e, I am in motion. To take an Instant Pic of me in motion would render me (and Time) motionless. But that would place relative, definitive points on two things that, well are defined as constantly changing. It looks like we are trying to describe the infinite as a finite system.
--Next is absolute zero. Okay, I think absolute zero is in a nutshell 'no movement even at the subatomic level'. I know that is simplifying things a little, but anyway. (Disregarding Laws of Thermodynamics, and Heisenburg's UP) If an object theoretically reached AZ, would that object cease to exist? Reason, aren't the atomic and subatomic all based around Bipoles? If there was no movement at all at the subatomic level wouldn't the energy required to create those bipoles be non-existant? Because energy would be movement and that would get us +AZ. What would happen?? Since Matter is, in a sense Energy, and there can be no energy at AZ, would that object simply cease to exist? Or is this another reason why AZ cannot be reached? Also, might it also go along with an impossiblity to take a Snapshot of Time??
These are just some things I've been pondering on. Remember I'm a newbie... So please don't sacrafice me to your Physics God.
Q+A=Knowledge^2
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Welcome to the forum, Q and A
Without getting too much into the infinite nature of time (which is more philosophy than physics) classical physics uses time as a way of describing the state of a system. The basic premise is that macroscopic objects (i.e. no quantum mechanics here) exist in a certain place at a certain time. The mathematics back it up...we need some calculus here. Let's say the location of an object in 1-dimensional space is x. The derivative of x with respect to time (dx/dt) is the velocity of that object. Let's say you graph that object's position as time passes...the slope of that graph is also the velocity. (rise/run or x/t) Do you see the relation? dx/dt simply means an infintesimal amount of movement over an infintesimal amount of time. I highly recommend you taking a calculus-based physics class to truly understand how time and motion interrelate.
To give you a more simple example of taking something finite from something infinite....look at any graph of an algebraic function. A simple line (y=x for instance) extends to infinity, but you can pick out a single point on it.
Now, regarding absolute zero...you really shouldn't just disregard thermodynamics when speculating the nature of absolute zero since they are the proof of why it is unattainable. But I digress. To answer your question, thermodynamically speaking ALL MOTION CEASES AT ABSOLUTE ZERO. Zero point Quantum motion is always there and that is what prevents collapse in the hypothetical scenario at absolute zero.
Hope that helps. I can recommend some great web sites if you want to read more about thermodynamics and/or quantum theory.
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Thanks Cannabinoid,
What I am saying regarding time is that it is being looked at as a physical property in modern physics. Although, it does not appear to me to be. This a newly developed theory that is steadily gaining acceptance (Peter Lynds). If Time, in nature, is not a physical property, then relative, definitive points cannot be obtained. If absence of time is taken into consideration, then many areas start to make a little more sense, i.e. Quantum mechanics. It makes sense to me that Time is a result of our brain, us being conscious. Therefore, being absent in nature, at least as a physical property. Representing the linear graph of distance between, object at point A and object at point B on a graph are the representations of physical props. Those objects are not in motion as relative to space, and nor space to it, so they can be graphed as relative points on a linear graph. They are not,however, static to Time, and Time is not static relative to the objects. Time is in motion. The objects are in motion as well (But on the Quantum Level!)(Even at AZ) Which I guess is my point with Absolute Zero and its impossiblity. We cannot reach AZ because that would stop even zero point motion, but you cannot stop it. Because doing so would take a definitive point of Time. Continuity, cannot be graphed through static points because it is infinitly in motion (infinite being redundant), Thus Time, Motion, Velocity are not physical properties. They are viewed that way by our brain.
I said to disregard Thermodynamics and H's UP, because while they are commonly based as law, I try to view them as law/theory, to try to unveil new outlooks. What if "law" for a certain result is only a result of that result,not law. The true law being found in an area that we have not even begun to grasp yet?
And as for Calculus, I did take it in high school, but Im sure that I could use some brushing up. But I really don't think that it pertains to a relationship with Time. I am not the only one who is looking at it this way. Check out Peter Lynds' homepage. Tell me what you think.
Q+A=Knowledge^2
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I would argue that time is most certainly a physical property (but an extensive rather than intensive one) and just as important as position in space. I'll check out that web site, though. I keep an open mind obout things, but when you really start doing the math (and you truly cannot, and I mean absolutely cannot, understand the interrelations between time, space, and matter without higher mathematics) you start to see how a lot of current theories came to be and how they apply to the universe.
Someone once said "Time exists so everything doesn't happen all at once, space exists so that everything doesn't all happen to YOU."
BTW, time is used in quantum mechanics...Schrodinger developed two sets of equations, one set for time dependency, the other for non-time-dependency. The time-dependent equations are harder to use, but they're certainly valid.
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Welcome QandA! You bring up some very interesting ideas here. I don't claim to be an expert, so don't think I am.
I agree with you that the "law" of thermodynamics is really a theory. Actually, it is a classical theory that is highly accurate and well proven for relatively large amounts of matter. This is a situation where the atomic, molecular, and quantum effects all average out. Certainly at the quantum level, there may be other ways of expressing it, and most likely other (un-thought) theories that can express and explain things better.
I also agree with cannabinoid that you cannot grasp modern scientific theories without higher mathematics. And I mean a LOT higher than high school calculus. In addition to the math, you need the science classes that come after them (not before, or you'll be lost) to understand what the math is describing and how it fits with other areas.
Time as a physical property is a concept that goes back quite a way. As cannabinoid pointed out, there are different ways of expressing quantum theory using time or not using time. I think that is one of the faults of quantum mechanics. So, maybe time is a figment of our imagination, and our imagination always wants to put time into the equations that we use to describe our world.
As I said, I'm no expert, but it's fun thinking about it.
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John
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Good points Tweener,
I am no expert either and I think that maybe I got off on the wrong on the wrong foot. I am NOT suggesting that Quantum Mechanics and Physics altogether do not involve math. I know that they do, and they do so at a level that I will probably never truthfully grasp. I am merely suggesting that Time, as intervals, does not exist. So it cannot be analyzed by mathematics, or really even at all. It a concept that only relates to our understanding. Time just IS. There is no flow of time, because a flow can be stopped. If that is the case, that would open up a whole new can of beans.
And as cannabinoid pointed out, there are ways that have been developed to analyze QM without reference to Time as intervals, but it seems like most mathematicians cannot handle that theory, because it is outside of their comfort zone. Thus, these theories have been suppressed a bit maybe hindering our scope of things.
And The Law of Thermodynamics, I know, certainly does apply, but maybe it isn't the big reason of why we can't reach absolute zero.
These are just my personal opinions at the moment. I too, have an open mind. So, these thoughts are subject to change. I think maybe I came in spouting off too much at once, and sounded like a know-it-all, but believe me, if I know anything at all, it's nothing.
Q+A=Knowledge^2
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No, you don't sound like a know it all. You sound like someone interested and asking good questions. I certainly don't have the answers.
As to the mathematics, I have been exposed to some forms of higher math, but I never had the intuitive grasp that some people have. I have known people that can "feel" an equation. They can sense when it is right or wrong. I just have to look at it and brute force my way through. I have no hope of really grasping the esoteric aspects of truly cutting edge physics, because I just don't have the mentality for the math that is used to describe it.
But I have fun trying! [:D]
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John
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Q and A,
Don't think of time so much as an entity in and of itself, think of it as another dimension for matter and energy to exist in. All things need to occupy a certain space, but they do so at a certain time. You cannot completely describe a system without specifying a time. If you're trying to hit a moving ship with a cannon, shooting where it was 20 minutes ago won't work. It's just a way of organizing space. Hence the term space-time continuum.
As for the "flow" or linearity of time, our perception makes it seem linear, but since we have not been around since the origins of the universe we can't say for sure. It's a matter of scale...linear time models work for the scale in which we operate, but to a very small creature on a very big circle, that circle seems rather linear too. For now, we can only accept what works out in the math of it all.
This stuff isn't just made up, it's researched and experimented on, and then that research is reproduced by third parties.
As for thermodynamics, they're not laws in the same sense of gravity. They're more like rules of thumb...there are rather rare exceptions (usually in the quantum realm) but they're always true at the macroscopic level. In fact, one of the reason quantum physics was applied to certain areas of physics and chemistry is because there are some things that thermodynamics cannot explain. (like why liquid oxygen can be held in a magnetic field) There is mathematical proof that you cannot reach absolute zero through a series of finite processes, (third law) and I'll be happy to point you in the direction of that proof if you'd like to see it. The math isn't all that bad.
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