dr. undefined Posted March 10, 2012 Posted March 10, 2012 Can anyone quietly elucidate what is time? I mean while defining Time people in general relate them to be just a measure of something. That "something" can't be defined by them!
swansont Posted March 10, 2012 Posted March 10, 2012 In physics, time is what is measured by a clock. Asking what time is is a question of metaphysics. 1
dr. undefined Posted March 10, 2012 Author Posted March 10, 2012 In physics, time is what is measured by a clock. Asking what time is is a question of metaphysics. That's what I am asking Sir! People don't or can't define it as under the grounds of QM or GR at a large order. While asking it under grounds of metaphysics is it the best answer to be defining it as if the storage of memories and stuff?
ydoaPs Posted March 10, 2012 Posted March 10, 2012 In physics, time is what is measured by a clock. Asking what time is is a question of metaphysics. In metaphysics, it's the separation between states. 1
DrRocket Posted March 10, 2012 Posted March 10, 2012 In physics, time is what is measured by a clock. Asking what time is is a question of metaphysics. And distance is what a ruler measures. We have no more basic definition of distance than we have of time. But for some reason people are more comfortable with rulers than with clocks. Nobody seems to ask what distance is.
dr. undefined Posted March 11, 2012 Author Posted March 11, 2012 And distance is what a ruler measures. We have no more basic definition of distance than we have of time. But for some reason people are more comfortable with rulers than with clocks. Nobody seems to ask what distance is. I think people do that for they have a least satisfactory answer to define it but time doesn't have such a definition.
Temporocitor Posted March 12, 2012 Posted March 12, 2012 Can anyone quietly elucidate what is time? I mean while defining Time people in general relate them to be just a measure of something. That "something" can't be defined by them! Time is intrinsically a flow of particles. We can measure the flow of photons from point A to point B to ..... point n. Planck time is a division of time based upon the speed of light. I'll venture as far as to say there likely is a basic, primordial particle that breaks the unit down to an absolute degree of infinitesimality. The Higgs field or Boson? According to Lederman and Schramm the initial instance of material time was 10 -43 seconds. Beyond that I would need to develop a theory of everything to support it and would be best addressed as a seperate launch post.
DrRocket Posted March 13, 2012 Posted March 13, 2012 I think people do that for they have a least satisfactory answer to define it but time doesn't have such a definition. The definition of distance is not one bit "better" or more fundamental than the definition of time.
natedawgwoodbury Posted March 20, 2012 Posted March 20, 2012 time is 2 things. time is a way to determine how fast the earth moves arond the sun and rotates. also time is a speed at a pase. i think the pase of time is 80000 miles per second. if you brak this speed things around you will go faster. i think time travel is possible. sincerly- 5 grade student, nate
ydoaPs Posted March 21, 2012 Posted March 21, 2012 time is 2 things. time is a way to determine how fast the earth moves arond the sun and rotates. also time is a speed at a pase. i think the pase of time is 80000 miles per second. if you brak this speed things around you will go faster. i think time travel is possible. sincerly- 5 grade student, nate When you get deeper into physics, you'll learn about dimensional analysis. If we have an equation, the type of units have to match on each side. We can't have pounds equal to feet. Those sort of equations make no sense. So, we have to make sure things which are equal have the same type of units. 4 feet may equal 48 inches, but to say that it equals 18 pounds is wrong to the point of not meaning anything. Now, you said time has is 80000 mps. But we measure time in seconds and minutes. Where does the length in the units come from? That speed is very special, but it's not the speed of time. It is the speed of light and nothing with mass can travel at that speed and nothing can travel faster. Light, however, always travels at that speed for everyone. This has consequences for time and space itself. When we allow the speed of light to be the ultimate speed limit, let the speed of light be the same for everyone, and and keep in mind that all inertial frames of reference give equally valid answers, we find something amazing. The magnitude of length and duration both depend on how fast you're going relative to someone else. AND since the same is true of them, we get really cool situations like the twin paradox. In the twin paradox, we have two observers moving very quickly relative to each other. They each see the other as being thinner and having slower clocks. And they're both right. 1
swansont Posted March 21, 2012 Posted March 21, 2012 Time is intrinsically a flow of particles. Um, no. How would you establish this, scientifically? i.e. a falsifiable test? 1
shawnhcorey Posted March 21, 2012 Posted March 21, 2012 Time is a mathematical illusion. Like all mathematical illusions, it is both consistent and persistent. What is is it the distance travelled by the superposition of a quantum event until it collapses.
ydoaPs Posted March 21, 2012 Posted March 21, 2012 Time is a mathematical illusion. Like all mathematical illusions, it is both consistent and persistent. What is is it the distance travelled by the superposition of a quantum event until it collapses. Please define "persistent" without the use of time.
shawnhcorey Posted March 21, 2012 Posted March 21, 2012 Please define "persistent" without the use of time. People think it's real. Their belief is persistent.
ydoaPs Posted March 21, 2012 Posted March 21, 2012 People think it's real. Their belief is persistent. You didn't actually define what the word means; you just used it.
swansont Posted March 21, 2012 Posted March 21, 2012 What is is it the distance travelled by the superposition of a quantum event until it collapses. I have no idea what this is supposed to mean. 1
shawnhcorey Posted March 21, 2012 Posted March 21, 2012 You didn't actually define what the word means; you just used it. Its meaning is implied by its usage, the same as any other word. What is is it the distance travelled by the superposition of a quantum event until it collapses. I have no idea what this is supposed to mean. From Wikipedia's Quantum Superposition page: Quantum superposition is a fundamental principle of quantum mechanics. It holds that a physical system (say, an electron) exists partly in all its particular, theoretically possible states (or, configuration of its properties) simultaneously; but, when measured, it gives a result corresponding to only one of the possible configurations (as described in interpretation of quantum mechanics). It is the distance between the event and where it is measured. Since the superposition travels at the speed of light, it is also the time.
swansont Posted March 21, 2012 Posted March 21, 2012 From Wikipedia's Quantum Superposition page: Quantum superposition is a fundamental principle of quantum mechanics. It holds that a physical system (say, an electron) exists partly in all its particular, theoretically possible states (or, configuration of its properties) simultaneously; but, when measured, it gives a result corresponding to only one of the possible configurations (as described in interpretation of quantum mechanics). Yes, I understand what a superposition of states is. It is the distance between the event and where it is measured. Since the superposition travels at the speed of light, it is also the time. But here you have "event", and a distance between the "event" and where it is measured, and have not tied that back to any superposition of states. Further, saying that a superposition travels at c makes no sense to me. Let's say I put an electron in a superposition of spin up and spin down. What is the event, and what is traveling at c?
ydoaPs Posted March 21, 2012 Posted March 21, 2012 Its meaning is implied by its usage, the same as any other word. The implied usage presupposes the existence of time. Would you like to try again?
shawnhcorey Posted March 21, 2012 Posted March 21, 2012 Let's say I put an electron in a superposition of spin up and spin down. What is the event, and what is traveling at c? The event is when you put the electron in a superposition of spin up and spin down. The superposition of state is a sphere that expands at the speed of light. When a quantum event happens, you don't know what it is until it is measured. It is only when it's measured does the superposition collapses and you know what occurred. All superpositions expand at the speed of light, so a measure of the distance between the event and the measure defines time.
swansont Posted March 21, 2012 Posted March 21, 2012 The event is when you put the electron in a superposition of spin up and spin down. The superposition of state is a sphere that expands at the speed of light. A superposition being a sphere expanding at c sounds like gibberish. When a quantum event happens, you don't know what it is until it is measured. It is only when it's measured does the superposition collapses and you know what occurred. All superpositions expand at the speed of light, so a measure of the distance between the event and the measure defines time. If you don't know about it until it's measured, how do you know how where the event happened? What about events that are not superpositions? How would you test any of this? — Let's say I put an electron in a spin superposition, and it's in a mercury ion in a trap. I let the superposition exist for a second before measuring it. The ion didn't go anywhere — it's in a trap. What is 3e8 meters away that I measure? 1
md65536 Posted March 22, 2012 Posted March 22, 2012 All superpositions expand at the speed of light, so a measure of the distance between the event and the measure defines time. Is this the same as saying that probability waves propagate at c? Or perhaps that possible information about an event travels at c? The ion didn't go anywhere — it's in a trap. What is 3e8 meters away that I measure? Assuming that you're measuring some information from an event that occurred 1 second ago and that the information travelled at c, then the information would have oscillated or something while trapped, still travelling a total of 3e8 meters (and still defining a time). Information or probability waves don't have to be measured in order to change direction, do they? The "expanding sphere" would only be the simplest case, that of no change in direction.
swansont Posted March 22, 2012 Posted March 22, 2012 Information or probability waves don't have to be measured in order to change direction, do they? The "expanding sphere" would only be the simplest case, that of no change in direction. What is an information wave or a probability wave? 1
md65536 Posted March 22, 2012 Posted March 22, 2012 What is an information wave or a probability wave? (Information), or... (a probability amplitude described by a wave function?) I suppose the latter doesn't make sense, because a wave function doesn't carry information about an event, but rather information about a particle??? So the wave function doesn't propagate at the speed of light, but at the velocity of the particle (limited by c)??? Bell's theorem implies violation of locality or counterfactual definiteness. Does non-locality imply superluminal transmission of "useful" or exploitable information? There is neither experimental evidence for that, nor any accepted theoretical prediction of it that I know of. Meanwhile there seems to be much evidence of violation of counterfactual definiteness. I suppose there's not enough evidence to say which is violated, and so guessing would be silly. How about: A particle without rest mass propagates away from an event at c, as a probability amplitude describing the state of the particle, whose wavefront is a sphere of radius c*t, where the magnitude of the amplitude may be severely directionally biased. ???
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