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Absolute time and the speed of light

Use this forum to discuss the philosophy of science. Philosophy of science deals with the assumptions, foundations, and implications of science.
Steve3007
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Re: Absolute time and the speed of light

Post by Steve3007 » January 25th, 2019, 7:41 am

Fdesilva wrote:Here is the deal. The universe that is going to be in a say a billionth of a second from now. Does it exist now?
No, it doesn't.

But I think we have to be clear about our use of temporal language. Clearly to say that it did exist now would be a self-contradiction. Making the language more explicit, it would be saying: "a time in the future is the time now.". The spatial linguistic equivalent to this is not "the space to my left exists now". It is "the space to my left is the space where I am", which is of course also a self-contradiction.
...Now what I am saying is that the space that this path enters into is not space that pre existed but new space, just like the time that the object entered to is new time. This is a hypotheses.
I think the implicit temporal nature of the language causes unnecessary confusion here. The term "pre existed" uses the prefix "pre" which is usually a reference to time not space. So "pre exist" means "exists at an earlier point in time". So clearly, by definition, the future doesn't "pre exist". But in the context of 4 dimensional spacetime, the past and future exist in exactly the same sense that the space to my left and right exist. They obviously don't exist "now" because "now" is a purely temporal word, not a spatial one. Saying "the future does not yet exist" or "the future does not exist now" is not linguistically equivalent to saying "the space to my left does not exist now". It's linguistically equivalent to saying "the space to my left does not exist at the place where I am".

This is why I say we have to be very careful when throwing around temporal words while discussing spacetime.

Saying "the time that the object entered is new time" does not distinguish time from space in the way that I suspect you think it does. It simply means "the time that the object entered is not the time that it left". The spatial equivalent is: "the space that the object entered is not the space that it left". You don't need to invoke the expanding Universe for both these statements to be true.

Steve3007
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Re: Absolute time and the speed of light

Post by Steve3007 » January 25th, 2019, 7:48 am

Present awareness wrote:If I’m walking down the street and look behind me, the space I was just in is still there and the space I’m walking towards is also there. Everything is here now, regardless of one’s particular location. Everything is in a state of constant motion from the galactic to the microscopic, even when I feel like I’m sitting still in my chair! However, no matter how far we go or where we move to, we never leave the present moment.
Yes, by definition we never leave the present moment because the present moment is defined as the moment that we're in. Likewise, we never leave our present spatial location because our present spatial location is defined as the one we're in.

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Re: Absolute time and the speed of light

Post by Steve3007 » January 25th, 2019, 8:03 am

Present awareness wrote:If I’m walking down the street and look behind me, the space I was just in is still there and the space I’m walking towards is also there
As I was discussing with Fdesilva, I think when discussing the nature of space and time we have to be very careful how we use temporal language - language with explicit or implicit references to time in it.

In the above quote, the words "just" and "still" are temporal words. "The space I was just in is still there" means:

"The same point in space corresponds to more than one point in time".

It's tempting to think that the spatial equivalent of that sentence is "The time I was just in is still there" and then to say "Aha! But it isn't! That time doesn't exist now!". But that is not the spatial equivalent of that sentence because it fails to convert the words "just" and "still" from temporal to spatial words. The spatial equivalent of that sentence is:

"The same point in time corresponds to more than one point in space".

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Re: Absolute time and the speed of light

Post by Present awareness » January 25th, 2019, 12:17 pm

The arrow of time seems to flow from past to present to future and our language reflects that idea with past, present and future tense in our speaking. Words like “was” “is” or “will be” refer to changes we observe in the present moment. It “was” dark but now it “is” light, but it “will be” dark again soon. By definition, the present moment is “now”, it does not arrive nor does it leave. We may measure the changes which happen within the present moment, we may predict changes the will happen in the present moment, but we may never actually leave the present moment itself.

If it were possible to step outside of oneself, and observe from an objective point of view, zoomed out so far that one could observe the entire universe you would see light that left stars hundreds, thousands, even millions of years ago. It’s all still there, at different points in space and time. What we call the past, present or future would all depend on your point of view.
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Re: Absolute time and the speed of light

Post by Steve3007 » January 25th, 2019, 12:45 pm

By definition, the present moment is “now”, it does not arrive nor does it leave. We may measure the changes which happen within the present moment, we may predict changes the will happen in the present moment, but we may never actually leave the present moment itself.
Yes, and as I said, by definition, in exactly the same sense, we cannot leave the present location. The present location is, by definition, where we are just as the present moment is, by definition, when we are.

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Re: Absolute time and the speed of light

Post by Steve3007 » January 25th, 2019, 12:55 pm

What we call the past, present or future would all depend on your point of view.
Yes, just as what is immediately in front of or behind me depends on where I am. To be honest, this is all pretty obvious stuff isn't it?

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Re: Absolute time and the speed of light

Post by Present awareness » January 25th, 2019, 2:27 pm

Yes, it all seems obvious to me Steve 3007 but fdesilva was asking: “ The universe that is going to be in a say a billionth of a second from now. Does it exist now?” I believe that it does and was trying to point out why I think that way.
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Re: Absolute time and the speed of light

Post by Fdesilva » January 26th, 2019, 4:29 pm

Steve3007 wrote:
January 25th, 2019, 7:41 am
Fdesilva wrote:Here is the deal. The universe that is going to be in a say a billionth of a second from now. Does it exist now?
No, it doesn't.

But I think we have to be clear about our use of temporal language. Clearly to say that it did exist now would be a self-contradiction. Making the language more explicit, it would be saying: "a time in the future is the time now.". The spatial linguistic equivalent to this is not "the space to my left exists now". It is "the space to my left is the space where I am", which is of course also a self-contradiction.
...Now what I am saying is that the space that this path enters into is not space that pre existed but new space, just like the time that the object entered to is new time. This is a hypotheses.
I think the implicit temporal nature of the language causes unnecessary confusion here. The term "pre existed" uses the prefix "pre" which is usually a reference to time not space. So "pre exist" means "exists at an earlier point in time". So clearly, by definition, the future doesn't "pre exist". But in the context of 4 dimensional spacetime, the past and future exist in exactly the same sense that the space to my left and right exist. They obviously don't exist "now" because "now" is a purely temporal word, not a spatial one. Saying "the future does not yet exist" or "the future does not exist now" is not linguistically equivalent to saying "the space to my left does not exist now". It's linguistically equivalent to saying "the space to my left does not exist at the place where I am".

This is why I say we have to be very careful when throwing around temporal words while discussing spacetime.

Saying "the time that the object entered is new time" does not distinguish time from space in the way that I suspect you think it does. It simply means "the time that the object entered is not the time that it left". The spatial equivalent is: "the space that the object entered is not the space that it left". You don't need to invoke the expanding Universe for both these statements to be true.
Present awareness wrote:
January 25th, 2019, 2:27 pm
Yes, it all seems obvious to me Steve 3007 but fdesilva was asking: “ The universe that is going to be in a say a billionth of a second from now. Does it exist now?” I believe that it does and was trying to point out why I think that way.
Hi Steve3007 and "Present awareness"
Yes the current excepted version of the universe it is 4 Dimensional object. The future past and the present exist. Now importantly the answer to the question why am I at this moment and not say yesterday. The answer is a bit like groundhog day, it is groundhog moments. That is, there are my past and future version living in there respective present moments.
No What I am putting forward is an alternate hypotheses. Now if you accept the above which I believe you do then really introduces only a subtle difference.
First this 4 Dimensional universe when did it get formed? The theory about the big bang says there was a rapid expansion soon after the big bang. It is in that rapid expansion that the future moments that you are about to enter get created. The reason I believe it was taken to be this way was because all of physics assumes that the space and time of the future always exist.
What I mean by that is if you take Newtonian physics it assumes space time as always having being there. The space-time for the future does not need any creation. However we now know that space-time itself got created at the big bang. So all I am saying is that there was no rapid expansion that created the future space time. The expansion is fundamental. The now is the edge of space time. Moving forward in time is one and the same as create the future 4D universe.
So in my model the past is exactly like the current. But the future is getting created as we move into it.
As you say if we could step out of the universe then the current excepted model will show an 4D universe fully formed stretching from the big bang to infinity in time and space. In the model I am proposing it would a 4d object stretching from the big bang to the current moment and as you watch it keeps expanding creating the future.

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Re: Absolute time and the speed of light

Post by Present awareness » January 26th, 2019, 6:01 pm

Your idea is interesting Fdesilva and I certainly have no way to prove that it’s wrong. As the future unfolds before our eyes, it does appear to be new and freshly created. However, things are not always as they appear to be. Take a movie for example, flash a series of still pictures quickly before the eyes and it appears like things are moving in a motion picture.

I tend to believe that everything that is here and now, has always been here and now, only in different forms. All forms are impermanent and constantly changing, within what we call the present moment. Nothing created and nothing destroyed, just constant change in form.
The sunlight that left the sun a thousand years ago is still out there, travelling through space. The sunlight that left the sun a minute ago is also out there heading towards the earth and will arrive in roughly 7 more minutes. One is in the past and the other in the future but they both exist in the present.
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Re: Absolute time and the speed of light

Post by Fdesilva » January 26th, 2019, 7:50 pm

Present awareness wrote:
January 26th, 2019, 6:01 pm
Your idea is interesting Fdesilva and I certainly have no way to prove that it’s wrong. As the future unfolds before our eyes, it does appear to be new and freshly created. However, things are not always as they appear to be. Take a movie for example, flash a series of still pictures quickly before the eyes and it appears like things are moving in a motion picture.

I tend to believe that everything that is here and now, has always been here and now, only in different forms. All forms are impermanent and constantly changing, within what we call the present moment. Nothing created and nothing destroyed, just constant change in form.
The sunlight that left the sun a thousand years ago is still out there, travelling through space. The sunlight that left the sun a minute ago is also out there heading towards the earth and will arrive in roughly 7 more minutes. One is in the past and the other in the future but they both exist in the present.
Here is a bit more descriptive power in what I am suggesting for you to ponder. I am sure you are familiar with the concept of collapse of the wave function in quantum mechanics. So in my view the growing or expanding edge of the universe is the now. It is also where the collapse of the wave function takes place. The wave function simply describe the expansion (= motion) of matter. The past is where it has collapsed. The now is the un-collapsed state.

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Re: Absolute time and the speed of light

Post by Present awareness » January 26th, 2019, 8:43 pm

I tend to think of the now as the space in which each individual occupies, so that your now will always be different from my now or anyone else’s now. It is the same with consciousness, in that your consciousness is all that exists from your own personal point of view, for you may never know what anyone else’s consciousness is like. Even the idea that we exist as individuals is faulty, for it is based on past memories of whom we were, what we did and what others say about us. The child we once were is long gone and the teenager we once were is also long past. When we die, we will die in the now and it is only the person in the now that will actually died, since all previous versions of ourselves have already long since perished!
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Re: Absolute time and the speed of light

Post by Fdesilva » January 26th, 2019, 9:12 pm

Present awareness wrote:
January 26th, 2019, 8:43 pm
I tend to think of the now as the space in which each individual occupies, so that your now will always be different from my now or anyone else’s now. It is the same with consciousness, in that your consciousness is all that exists from your own personal point of view, for you may never know what anyone else’s consciousness is like. Even the idea that we exist as individuals is faulty, for it is based on past memories of whom we were, what we did and what others say about us. The child we once were is long gone and the teenager we once were is also long past. When we die, we will die in the now and it is only the person in the now that will actually died, since all previous versions of ourselves have already long since perished!
Yes what you say is true in regards to our bodies. Memory is a part of are body as such what you say about accuracy of memory is also true as it has a physical inbuilt mechanism that archives or forgets. Your view of the universe and we as a part of it is a deterministic. It does not allow Free will. Now we can right of free-will an say there is no such thing. However here is a possibility. You and I agree that the universe is 4D structure. Now what if it’s a flexible structure. What if you can change it 4 Dimensionally. Any such change will not be detected from within. Neither will it violate the laws of physics. So my hypotheses on consciousness is this. The thing you call me at the centre of all your conscious experiences is the little bit of space-time in your brain at the current moment. The senses create electromagnetic fluctuations in this little bit. You have the ability to change the curvature just like mass can. Thus if you shorten the time around a firing nerve it will increase the frequency and make a muscle move. Thus giving you free will. The biggest evidence I have in favour of this view is that we are aware of simultaneous events. Further think of listening to music. Music essentially spans time. There fore we must be 4D in the least.

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Re: Absolute time and the speed of light

Post by Present awareness » January 26th, 2019, 9:25 pm

I believe in free will in the sense that we may choose between two equally attractive options. Some may say that whatever we choose, we were destined to choose, but that is only because hindsight is 20/20.
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Re: Absolute time and the speed of light

Post by Fdesilva » January 27th, 2019, 1:48 am

Present awareness wrote:
January 26th, 2019, 9:25 pm
I believe in free will in the sense that we may choose between two equally attractive options. Some may say that whatever we choose, we were destined to choose, but that is only because hindsight is 20/20.
At a psychological level I would agree with you. The space of thoughts is infinite. You have an infinite choice of a thought to choose (think of the number set 1,2,3 …). Obviously you cannot go through an infinite list of thoughts so doing to at a time is good enough. Chain them up and you end up with a very unique product of thought such as a painting.

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Re: Absolute time and the speed of light

Post by Steve3007 » January 28th, 2019, 6:31 am

Present awareness wrote:Yes, it all seems obvious to me Steve 3007 but fdesilva was asking: “ The universe that is going to be in a say a billionth of a second from now. Does it exist now?” I believe that it does and was trying to point out why I think that way.
OK, that's interesting because to me that sounds like saying you believe 2 + 2 = 5. According to my understanding of the English language, the word "now" means "zero seconds away" and "a billionth of a second from now" means "a billionth of a second away", so, to me, it would be a simple self-contradiction to say that the universe at some future time is the universe now. A bit like saying the place 2 feet to my right is the place 2 feet to my left. Or like saying Edinburgh is London. Or like saying 9pm is 10pm. Stuff like that.

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