Utopia and Time Travel
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JimOfAllTrades
Master Poster
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It is cool.
And I think I've learned from your posts. I don't pretend to understand SR in anything but extremely broad strokes, but it's fascinating, and working through examples is always a bit boggling, and fun.
RussDill
Philosopher
It is cool.
And I think I've learned from your posts. I don't pretend to understand SR in anything but extremely broad strokes, but it's fascinating, and working through examples is always a bit boggling, and fun.
Check out PBS space time on YouTube.
psionl0
Skeptical about skeptics
If you got through to TGF then you have done well. (Forget about Navigator).
The Greater Fool
Illuminator
2. At any instant, reality exists in a specific state;
I've been pondering this, trying to understand why I see something so clearly.
Let's take the bouncing ball on the moving train, again. This is a specific sequence of events, and at any instant within the sequence of events, everything is moving in a specific location in relation to everything else. Once this series of events is kicked off (dropping the ball on the moving train), the events are going to play themselves out. Period. Such events are occurring throughout reality on a micro through cosmic level: this body collides with that, hurtling it toward another, and on and on.
Thus, reality is happening in specific sequences. It is different now than it is now because of all these events.
SR explains how specific frames experience dance of reality, but it is a dance, and it has an undeniable sequence.
SR allows different reality frames a window into this massive reality, but only a window.
One way of understanding reality is applying a coordinate system to it, but the coordinate system is a construct. Reality happens in the way and in the sequence it occurs. So much is happening within reality that two events will necessarily happen at the same instant in reality.
Synchronicity in SR is different than in reality. SR requires a frame of reference, reality requires none.
There is a disconnect in there somewhere. I don't see how we can agree that reality is, was, and will be, yet cannot agree that multiple events occur concurrently in reality.
I've been pondering this, trying to understand why I see something so clearly.
Let's take the bouncing ball on the moving train, again. This is a specific sequence of events, and at any instant within the sequence of events, everything is moving in a specific location in relation to everything else. Once this series of events is kicked off (dropping the ball on the moving train), the events are going to play themselves out. Period. Such events are occurring throughout reality on a micro through cosmic level: this body collides with that, hurtling it toward another, and on and on.
Thus, reality is happening in specific sequences. It is different now than it is now because of all these events.
SR explains how specific frames experience dance of reality, but it is a dance, and it has an undeniable sequence.
SR allows different reality frames a window into this massive reality, but only a window.
One way of understanding reality is applying a coordinate system to it, but the coordinate system is a construct. Reality happens in the way and in the sequence it occurs. So much is happening within reality that two events will necessarily happen at the same instant in reality.
Synchronicity in SR is different than in reality. SR requires a frame of reference, reality requires none.
There is a disconnect in there somewhere. I don't see how we can agree that reality is, was, and will be, yet cannot agree that multiple events occur concurrently in reality.
The ball on the train was an explanation of Galilean Relativity, specifically the relativity of space, it isn't an example of SR, though I was hoping that as an analogy it might some aspects of SR a little easier to understand.
If reality happens in some sequence then what sequence? When Dave reads 12 noon on his clock, what time is it on Cindy's clock in reality?
If reality happens in some sequence then what sequence? When Dave reads 12 noon on his clock, what time is it on Cindy's clock in reality?
Your picture only works when everything is connected in some way. But things may be separated to such an extent that nothing I do here can affect something way over there within the "order of events" time frame. If there's no causal connection then the universe doesn't care whether I think one happened before the other or not.
psionl0
Skeptical about skeptics
Even though it seems to defy "common sense" you need to accept that there is no reality except with regards to a reference frame. This is a consequence of the fact that the speed of light is the same in all reference frames. "Reality" is just one of many reference frames.
To illustrate how relativity "defies" common sense, consider a person on a moving vehicle throwing a ball forward to somebody who is stationary. "Common sense" dictates that the receiver sees the ball approaching at the combined speed of the thrower and the vehicle. (Everybody knows that you just add the speeds).
Now consider what happens when the same person switches on a torch. The beam of light will leave the torch-switcher-onner at speed C. To the receiver, you would expect to add the speed of the vehicle to that of the beam of light to find out how fast the beam approaches them. However, it turns out that the same beam of light also reaches the receiver at speed C.
The Greater Fool
Illuminator
It is a fine example for reality also.
Like we agree, reality is. It happens. The bouncing ball on a moving train is as good an example of an event in reality as any other, no?
The sequence it happened in reality. The ball bounces on the moving train. It just *is*. AND, the bouncing ball on the moving train is a sequence of events that happen, observed or not, experienced or not.
THAT is our disconnect You are trying to frame reality. Reality is, it doesn't require a frame.
The clocks are devices that sequence events FOR THEM, from their frame.
Reality doesn't depend on what a clock says. Frames of reference do. The clocks help the frame understand what is being experienced. Reality doesn't care what "time" it is.
The ball is bouncing on a moving train. Bodies in space/time move and interact with each other. It is reality, reality doesn't care about you and your observation. The ball bounces on the moving train and planets, solar systems, universes, galaxies all move in a specific way, and in a sequence. It is rather by definition that they are and move and interact.
Perhaps the disconnect is that reality is so basic and obvious. You seem obsessed with reference frames so that WE can deal with reality, when I am stating the basic, obvious fact that reality is, and it happens in an [objective] sequence. Again, the ball actually does bounce on the moving train.
The Greater Fool
Illuminator
Perhaps you need to accept there is a reality independent of frames of reference.
Again, the ball on the moving vehicle is moving in space/time. It is a fact. It is reality. It is.
Your "common sense" is your downfall. From different frames of reference, the ball APPEARS to move in different ways. The reality is it moved in one way.
The reference frame does not define reality, it merely describes it. You are confusing the perception with the fact.
You are continually describing how the ball or beam or whatever moves objectively, then you describe how SR frames perceive that reality.
It is puzzling to me that you describe the reality, then describe the SR frames of reference, then somehow abandon reality you defined.
The Greater Fool
Illuminator
Of course things MAY be sufficiently seperated as to have no apparent relationship.
But, as you (I believe) pointed out, it all started with the big bang. Ultimately, everything is related, no matter how far removed from that initial event.
Exactly. The universe doesn't care what you think, nor what your frame is. The universe moves along it's merry way.
But things that were connected in the past might not still be connected (causal connection). If they move at different speeds through time then they might get mixed up.
We all start the race at the same spot. But some run in opposite directions at close to the speed of light. They become separated enough that they can no longer affect one another. There's no longer a causal link between them... or is there?
The Greater Fool
Illuminator
Again, all that's peachy. If that's reality, that's reality.
I don't think anyone is saying there isn't a reality, it's just that how we describe it - how we fit it in our heads - isn't so obvious. At least not to me.
For example, there's the idea that to be meaningful, we have to measure/observe it. And that's one way to claim what reality is. But that opens up the door to different people getting different measurements for what we think ought to be the same thing. Is our thinking wrong? Is the measurement wrong?
It's the "where do you stand" problem. We are embedded in the thing we want to look at as if we weren't trapped in it.
The Greater Fool
Illuminator
You say that events happen in a specific sequence. The clock reading a specific time is just an event. So what sequence do the events happen in?
If you don't like clocks, choose whatever you like. Dave and Cindy each have a bomb. Bob sees both bombs explode at the same time. Alice sees them explode at different times.
Do Dave and Cindy die at the same time or does Cindy outlive Dave? You are clearly saying that only one sequence of events can be true, so which is it?
Make it so one bomb going off first prevents the other bomb from exploding at all for an even more counterintuitive twist. One person lives and one dies, but who? Can we change our frame of reference and change the outcome?
psionl0
Skeptical about skeptics
I don't think that's possible. Information about one bomb going off can only be transmitted to the other bomb at the speed of light so there will be a delay during which the second bomb can still go off.
And that doesn't even consider relativistic effects.
Hokulele
Deleterious Slab of Damnation
Agree.
Don't want to add anything, as as that's where things seems to get dicey
Considering the speed of light may help show why there can't be a universal now. Do you accept that the speed of light is always c regardless of the reference frame?