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Pengwuino
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So what do you people think? What are the arguments for each?
Pengwuino said:Well that's my argument, the space-time theory. Someone said because you can't see it or measure it or "send it out", it can't be real.
Pengwuino said:So what do you people think? What are the arguments for each?
eNathan said:Hast thou heard of thyne theory of relativity?
Myriad209 said:I think time is simply a distinction from one event to another. Like watching the second hand on a clock tick as guile said. Motion of things sort of define time. Imagine a universe where everything stood completely still; you'd be hard-pressed to determine whether time is flowing or not.
And guile check for spelling... it gets annoying
gonpost said:So time is a measure of motion?
Then I have a question, in absolute zero, would time pass?
You can't measure time?? What does a clock do then? :tongue2:Pengwuino said:Well that's my argument, the space-time theory. Someone said because you can't see it or measure it or "send it out", it can't be real.
I don't think time is a thing or a human concept. I would like more items to chose from, please.Pengwuino said:So what do you people think? What are the arguments for each?
zoobyshoe said:I don't think time is a thing or a human concept. I would like more items to chose from, please.
I think discussions of time are all hindered by the inability to arrive at a good definition. It is an excruciatingly hard word to define, yet everyone understands what it means.<<<GUILLE>>> said:create your own one!
if not, you can't just say that you think another one is better to define time, because it's not even yours!
Isn't this the crux? It is the flow of time that may not be real, rather than time itself. Also, the "time is simply a distinction from one event to another" notion... the amount of time between two events cannot necessarily be agreed upon by two different observers. So one person may see the second hand on a clock move as we are used to, while another in a different frame of reference may see it move slower. This definition of time was exactly what special relativity overthrew.Myriad209 said:I think time is simply a distinction from one event to another. Like watching the second hand on a clock tick as guile said. Motion of things sort of define time. Imagine a universe where everything stood completely still; you'd be hard-pressed to determine whether time is flowing or not.
Wat is the difference between "the flow of time" and "time itself"?El Hombre Invisible said:Isn't this the crux? It is the flow of time that may not be real, rather than time itself.
Einstein defines time for the purposes of relativity by simply resorting to describing it as the movement of clock hands.Also, the "time is simply a distinction from one event to another" notion... the amount of time between two events cannot necessarily be agreed upon by two different observers.
What definition of time did it overthrow? I don't think it overthrew any definition of time, rather it merely complicated the meager one he presented. Relativity doesn't make time less real, just more flexible.So one person may see the second hand on a clock move as we are used to, while another in a different frame of reference may see it move slower. This definition of time was exactly what special relativity overthrew.
Einstein defined time as another dimension of the universe. Rather than an event taking time, an event occurs at a particular point in space and time. That event is what it is... those are it's co-ordinates [x,y,z,t]. There is nothing particularly special about anyone time co-ordinate. The flow of time makes the 'present' special... i.e. a particular event in space-time is in the present, all other events with a lesser time co-ordinate are in the past, and those with a greater time co-ordinate are in the future. We perceive time to be created and destroyed in the present, or the present itself as something that is moving from the past to the future. As a result, we feel we are moving forward in time, that time has a direction and flow. But do x, y and z have direction and flow? This flow is perceived because we remember the past and don't remember the future. I'm no expert but I did read an article explaining how there was no physical demand for this to be the case, and it may be a purely evolutionary device. Entropy probably plays the biggest part in our perceived arrow of time. Systems move from a more ordered state to a more disordered state. Maybe it's not possible to predict something doing the opposite, so entropy forces our hand at what information we can use to make decisions. Who knows? That's why I said the flow of time may be the illusion. But time itself... well, is space a human concept? Same goes for time, I guess.zoobyshoe said:Wat is the difference between "the flow of time" and "time itself"?
Yes, but those clock hands move differently for different observers or, at the extreme, do not move at all for some hypothetical observers. Therefore time can not give you any fixed distance between two events... it can only give you a relative value.zoobyshoe said:Einstein defines time for the purposes of relativity by simply resorting to describing it as the movement of clock hands.
SR overthrew Newtonian absolute time. It overthrew the notion that the time between event A and event B is set and the same for everyone.zoobyshoe said:What definition of time did it overthrow? I don't think it overthrew any definition of time, rather it merely complicated the meager one he presented. Relativity doesn't make time less real, just more flexible.
Stop right here, cause you've already stepped outside the bounds of linguistic rigor. Einstein employed time as the 4th dimension in a new way of analysis but this is not a definition of time. Einstein defined time as the movement of clock hands.El Hombre Invisible said:Einstein defined time as another dimension of the universe.
Did Newton actually assert an absolute time the same way he asserted an absolute space? I have been under the impression that the concept of an "absolute time" was just an assumption inherent in all physics and wasn't attributable to any particular individual.SR overthrew Newtonian absolute time. It overthrew the notion that the time between event A and event B is set and the same for everyone.
Ah, so you're in charge here... Yessir!zoobyshoe said:Stop right here, cause you've already stepped outside the bounds of linguistic rigor.
I would say, if you're getting into semantics, you're on dodgier ground. To say that Einstein defined time as the movement of clock hands is like saying he defined space as the length of a ruler. What Einstein said was that mechanical clocks serve for the definition of time. There are two important distinctions here: one is the word 'serve'. He is not saying a mechanical clock is the definition of time, but that for our purposes it will act as a definition. The second is the lack of mention of 'moving clock hands', the reason being that it is not the movement that is relevant, but the reading of the clock. For an observer with some given velocity, the reading of the clock gives a numeric co-ordinate, in the same way that the 100 cm mark on a ruler is only 100 cms from the 0 cm mark. So starting from t=0, when the observer checks his clock again and it reads thirty seconds, the time co-ordinate is t=30 (if the unit is seconds). Thus the clock gives you a measure of position in personal time. As I see it, this is no more what time is than the ruler is what space is. As for Einstein's view on time as the 4th dimension, he himself said that it makes no sense to separate the temporal dimension from the spatial ones when determining relations between events. i.e. to relate event A to event B in any objective way you must consider the spatial AND temporal relations between them together. This, in the context of this thread, seemed a more relevant definition of time than personal time.zoobyshoe said:Einstein employed time as the 4th dimension in a new way of analysis but this is not a definition of time. Einstein defined time as the movement of clock hands.
You think wrong. The two terms are very different. The memory of the past but not the future is an unsolved problem as there is no identifiable reason why this must be so. There is an observed flow of time that is not necessitated by time itself. I think what is happening here is that you have a personal definition of the word 'time' meaning 'the flow of time', which is how everything is used to thinking of time. But time in SR is isotropic. If you accept this, it is difficult to understand how you can not differentiate between the flow of time and time itself. In an interview with Penrose I read, he believed the consensus among physicists to be that the flow of time is an illusion - i.e. it is totally a consequence of perception. I won't pretend to have any idea as to the consensus on the flow of time among physicists, hence I stated that it may be an illusion.zoobyshoe said:"The flow of time" and "time itself" are, really, just turns of speech, also without a rigorous definition. I think the distinction you made between them is idiosynchratic to you.
Yes, he defined them together, in fact time first then space immediately after (Principia Mathematica):zoobyshoe said:Did Newton actually assert an absolute time the same way he asserted an absolute space? I have been under the impression that the concept of an "absolute time" was just an assumption inherent in all physics and wasn't attributable to any particular individual.
This question has been debated by scientists and philosophers for centuries. The answer is not straightforward. Time is a fundamental part of our understanding of the universe, but it is also influenced by our perception and measurement. Some argue that time is an abstract concept created by humans to help us make sense of the world, while others argue that time exists independent of human perception.
Time can be measured in various units, such as seconds, minutes, hours, days, etc. These units are based on the Earth's rotation and revolution around the sun. However, the measurement of time can also be influenced by factors like gravity and velocity. Scientists use highly precise instruments, such as atomic clocks, to measure time.
Currently, there is no scientific evidence that time can be manipulated or controlled. However, theories such as Einstein's theory of relativity suggest that time is relative and can be experienced differently by individuals based on their position and motion in space. Some scientists also explore the concept of time travel, but it remains a hypothetical concept and has not been proven.
The concept of time having a beginning or end is heavily debated among scientists and philosophers. Some theories suggest that time has always existed, while others propose that time began with the Big Bang and will eventually come to an end. The answer to this question is still unknown and continues to be a topic of research and debate.
Time and space are interconnected and are often referred to as the "fabric of the universe." Einstein's theory of relativity states that time and space are relative and can be influenced by factors such as gravity and velocity. The concept of spacetime helps us understand how time and space are intertwined and affect each other.