We have good discussions going about the space and how finite or infinite it is, but somehow we always take the concept if time for granted. The concept of time is even more confusing than the concept of higher spatial dimensions. We know how space started, and how it could possibly end, but what about time? Did it start with the space? How will it end? How is it tied to our universe?
BTW, do you know that in general, laws of physics cant tell the difference if time is running forward or backward. Things will not fall up for instance if the arrow of time flips. That makes the time more of an independent and even more mysterious phenomena.
I think time is independent of events occurring around. But what about those who believe in the possibility of traveling into past, with theory of relativity.
Monk, could you please further explain the “our brains sometime feels the ripples from the future” part?
Errm, on second thought, don’t.
There is nothing in Einstein’s theories that says that time travel to the past cannot happen, but his theories funny take care is the paradoxes. In our normal world, cause comes before the effect, always. Time travel to the past violates that principle.
On a side note, general image of time travel to the past (or the future) is very confusing in a normal persons mind. If you want to travel to the past, to the time when your dad was 10 years old (let’s say 1964), and you want to show up at his door step, then not only you have to travel throgh time, but also through space.
Our Space is continuously expanding, and our cluster of galaxy that includes our own milky way is flying away from the rest of the clusters at a very high speed. Then of course our own solar system is part of the spiral arm of the Milky Way, and is in constant revolution around the center. Then our earth is revolving around the sun. Keeping all these motions in mind, our earth is millions if not billions of miles away from the spot it was 50 years ago. Me traveling back in time to a specific place on earth is like a double edged sword. You have to figure out to travel through time, and have to figure out to travel through space, and it should be done in relatively short period of time (from your perspective) than it should normally take for you to travel through the same amount of space in real time
Monk, could you please further explain the "our brains sometime feels the ripples from the future" part?
Errm, on second thought, don't.
There is nothing in Einstein's theories that says that time travel to the past cannot happen, but his theories funny take care is the paradoxes. In our normal world, cause comes before the effect, always. Time travel to the past violates that principle.
On a side note, general image of time travel to the past (or the future) is very confusing in a normal persons mind. If you want to travel to the past, to the time when your dad was 10 years old (let’s say 1964), and you want to show up at his door step, then not only you have to travel throgh time, but also through space.
Our Space is continuously expanding, and our cluster of galaxy that includes our own milky way is flying away from the rest of the clusters at a very high speed. Then of course our own solar system is part of the spiral arm of the Milky Way, and is in constant revolution around the center. Then our earth is revolving around the sun. Keeping all these motions in mind, our earth is millions if not billions of miles away from the spot it was 50 years ago. Me traveling back in time to a specific place on earth is like a double edged sword. You have to figure out to travel through time, and have to figure out to travel through space, and it should be done in relatively short period of time (from your perspective) than it should normally take for you to travel through the same amount of space in real time
What if every moment exists in space and time really doesn't exist beyond what we synchronize our clocks with? Does the concept of time come from the harsh reality of entropy? Time is such a difficult concept to grasp that it took me a while to understand what special relativity is.
What if every moment exists in space and time really doesn't exist beyond what we synchronize our clocks with? Does the concept of time come from the harsh reality of entropy? Time is such a difficult concept to grasp that it took me a while to understand what special relativity is.
Are you saying that every moment of space and time is nothing but a fixed frame and running like a movie, (only that we are "in" the movie), also every frame stands on its own and disconnected with the previous or the next frame. and time is just a perception that comes from the constant running of that movie?
Concept of time did not come from entropy. Entropy is just a tool that shows that time is flowing in a specific direction.
And please dont pretend that now you have the grasp of the theory of special relativity. :p
Monk, could you please further explain the "our brains sometime feels the ripples from the future" part?
Errm, on second thought, don't.
There is nothing in Einstein's theories that says that time travel to the past cannot happen, but his theories funny take care is the paradoxes. In our normal world, cause comes before the effect, always. Time travel to the past violates that principle.
On a side note, general image of time travel to the past (or the future) is very confusing in a normal persons mind. If you want to travel to the past, to the time when your dad was 10 years old (let’s say 1964), and you want to show up at his door step, then not only you have to travel throgh time, but also through space.
Our Space is continuously expanding, and our cluster of galaxy that includes our own milky way is flying away from the rest of the clusters at a very high speed. Then of course our own solar system is part of the spiral arm of the Milky Way, and is in constant revolution around the center. Then our earth is revolving around the sun. Keeping all these motions in mind, our earth is millions if not billions of miles away from the spot it was 50 years ago. Me traveling back in time to a specific place on earth is like a double edged sword. You have to figure out to travel through time, and have to figure out to travel through space, and it should be done in relatively short period of time (from your perspective) than it should normally take for you to travel through the same amount of space in real time
What if every moment exists in space and time really doesn't exist beyond what we synchronize our clocks with? Does the concept of time come from the harsh reality of entropy? Time is such a difficult concept to grasp that it took me a while to understand what special relativity is.
I don't understand the theory. But I am not sure one has to go back in time AND space to recreate an event - such as showing up at father's doorstep in 1964.
if you consider earth to be a black box - spherical in this case - maybe it doesn't matter where in "universal" space the father's doorstep was in 1964. The frame of reference is the moving earth through space. So only travelling back in time may be relevant?
To be honest, I still struggle to understand special relativity. Happy now? So about time, yes, that is what I mean that every moment is an independent frame. Would we really have a “concept of time” if entropy didn’t increase or decrease? Without entropy, do we really know if time exists? If we couldn’t tell day from night or if we stopped aging, where does that leave time? We would only have it in equations of physics. That’s my point. Our concept of time is shaped by experiencing entropy. Everything experiences entropy, right? What is time below Planck Scale? What is it really?
The frame of reference is the moving earth through space. So only travelling back in time may be relevant?
So that means that if we can travel back to time, we can only travel to the places that we can travel to in the present time. I can take a plane and fly back to Pakistan to my dad's old house today. So I should be able to go back to the same house in 1964. But I cant go to Mars or Jupiter in my present time, so its no longer my local frame of reference, so I cant travel back in time and show up at Mars in year 1964.
Let me know if I am inline with your logic here? I am not arguing. Its a good assumption to base our further discussion on. I am just trying to understand it.
Even if you stop aging, or things stop decaying, or disorder stopped emerging from an order - even then you would still remember your past and future would still be unknown. The way your brain would be registering the information would tell you that time still exists and still flowing from past to the future.
What is time below Planck scale is a million dollar question. I wish someone could tell us that.
So that means that if we can travel back to time, we can only travel to the places that we can travel to in the present time. YES. I can take a plane and fly back to Pakistan to my dad's old house today. YES. So I should be able to go back to the same house in 1964. YES. BUT EVEN IF AN OLD BUILDING IS NO LONGER PRESENT, ONE SHOULD BE ABLE TO RECREATE THAT EXPERIENCE. SINCE THAT LOCATION IS ACCESSIBLE. But I cant go to Mars or Jupiter in my present time, SINCE its no longer my local frame of reference, so I cant travel back in time and show up at Mars in year 1964. GREAT POINT. HADN'T THOUGHT OF THAT. MAYBE WE CAN EXTEND THE FRAME OF REFERENCE LOGIC, AND DRAW A BLACK BOX AROUND THE MARS ORBIT AND EARTH ORBIT. SO REGARDLESS OF WHERE MARS AND EARTH ARE IN UNIVERSAL SPACE, ONE CAN GO TO A LOCATION IN MARS
Let me know if I am inline with your logic here? I am not arguing. Its a good assumption to base our further discussion on. I am just trying to understand it.
You are always polite. No issues. I understand why u had to ask those questions. Made me think also. My response in all caps (I don't know how else to insert comments).
Even if you stop aging, or things stop decaying, or disorder stopped emerging from an order - even then you would still remember your past and future would still be unknown. The way your brain would be registering the information would tell you that time still exists and still flowing from past to the future.
What is time below Planck scale is a million dollar question. I wish someone could tell us that.
That is a good point. Does entropy apply to our memories? Hmm.
Re post 10 "if entropy didn't increase or decrease", entropy only increases per 2nd law of Thermodynamics.
Yes, ultimately entropy only increases. I realize that. What I meant was if it neither increased nor decreased, what would be out experience of time. I added the bit about decreasing entropy to complete my hypothetical scenario.
You are always polite. No issues. I understand why u had to ask those questions. Made me think also. My response in all caps (I don't know how else to insert comments).
Ok I am understating your assumption more here. Lets take your current position as the the fixed point. Everything that is constant (or known) in terms of space/distance is your local frame of reference. That means that whole solar system is your local frame of reference because we knew exactly where Mars was, or Jupiter was on 18th of Jan 1964 with respect to us. So if we knew where it was, then we can time travel to it, as long as we are not leaving our local frame of reference.
But that means that time is a very local phenomena, and it must flow at different speeds in different parts of this universe (which in fact is true, and pretty much what Special Theory of Relativity talks about), and we can only time travel within our own local region. What I am trying to say that from our point of view, time slows down at the edge of a Black hole, so we can never time travel in past to that edge (at least not from our current location).
I have no idea if I am making sense or further confusing myself.
Ok I am understating your assumption more here. Lets take your current position as the the fixed point. Everything that is constant (or known) in terms of space/distance is your local frame of reference. That means that whole solar system is your local frame of reference because we knew exactly where Mars was, or Jupiter was on 18th of Jan 1964 with respect to us. So if we knew where it was, then we can time travel to it, as long as we are not leaving our local frame of reference.
But that means that time is a very local phenomena, and it must flow at different speeds in different parts of this universe (which in fact is true, and pretty much what Special Theory of Relativity talks about), and we can only time travel within our own local region. What I am trying to say that from our point of view, time slows down at the edge of a Black hole, so we can never time travel in past to that edge (at least not from our current location).
I have no idea if I am making sense or further confusing myself.
I think that makes sense.
Only thing I would add is -
One can draw boundaries around whatever regions one wants to revisit. That includes the solar system. And any subset of the solar system such as
Earth
Mercury
Venus
Etc.
So one can visit each of above places back in time.
Will read up on the special theory of relativity. Never heard of it. Or the Planck scale.
Ok I am understating your assumption more here. Lets take your current position as the the fixed point. Everything that is constant (or known) in terms of space/distance is your local frame of reference. That means that whole solar system is your local frame of reference because we knew exactly where Mars was, or Jupiter was on 18th of Jan 1964 with respect to us. So if we knew where it was, then we can time travel to it, as long as we are not leaving our local frame of reference.
But that means that time is a very local phenomena, and it must flow at different speeds in different parts of this universe (which in fact is true, and pretty much what Special Theory of Relativity talks about), and we can only time travel within our own local region. What I am trying to say that from our point of view, time slows down at the edge of a Black hole, so we can never time travel in past to that edge (at least not from our current location).
I have no idea if I am making sense or further confusing myself.
You are making sense. Time is relative to where we are in space. Pop Quiz: If we are ever able to colonize the moon, will people on the moon age faster than the people on earth? How does the earth's gravity affect time on the moon?
So about time, yes, that is what I mean that every moment is an independent frame. Would we really have a “concept of time” if entropy didn’t increase or decrease? Without entropy, do we really know if time exists? If we couldn’t tell day from night or if we stopped aging, where does that leave time? We would only have it in equations of physics. That’s my point. Our concept of time is shaped by experiencing entropy. Everything experiences entropy, right? What is time below Planck Scale? What is it really?