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doberg48
2nd March 2012 - 06:00 AM
ok,if you travel back in time and find ourselves there alive and living our lives ,what does that really mean for us when we die in present,are we still alive in past living our lives back to future when we die ,makes me think
Robittybob1
2nd March 2012 - 07:58 AM
QUOTE (doberg48+Mar 2 2012, 06:00 AM)
OK,if you travel back in time and find ourselves there alive and living our lives ,what does that really mean for us when we die in present,are we still alive in past living our lives back to future when we die ,makes me think

What actually happens is that you always make it back in time to pass away in peace.
So the secret is to always go back and back to make it last as long as you can.
mik
7th March 2012 - 06:10 PM
QUOTE (doberg48+Mar 2 2012, 06:00 AM)
ok,if you travel back in time and find ourselves there alive and living our lives ,what does that really mean for us when we die in present,are we still alive in past living our lives back to future when we die ,makes me think

You are confusing science fiction with science. "Time travel" is the former. The past is over and will never again be present. The future is not yet present. When "tomorrow comes" it will be "today", the present. There is only ever the present. That's what "is" means.
Robittybob1
7th March 2012 - 06:26 PM
QUOTE (mik+Mar 7 2012, 06:10 PM)
You are confusing science fiction with science. "Time travel" is the former. The past is over and will never again be present. The future is not yet present. When "tomorrow comes" it will be "today", the present. There is only ever the present. That's what "is" means.

The present or now is but a singularity. It can shortened to a 1 Planck Time period, so small it is unbelievable but ahead of that "now" is future and behind it is the past.
For if you say "Today" is the present then so is tomorrow and next year and so on and don't forget about yesterday and so on.
mik
7th March 2012 - 07:18 PM
QUOTE (Robittybob1+Mar 7 2012, 06:26 PM)
The present or now is but a singularity. It can shortened to a 1 Planck Time period, so small it is unbelievable but ahead of that "now" is future and behind it is the past.
For if you say "Today" is the present then so is tomorrow and next year and so on and don't forget about yesterday and so on.

The present is the ongoing 'now,' not a "time period" however short.
"The future is not yet *present.* The past is not still *present.* What about this do you find difficult to understand?
You say:
"For if you say "Today" is the present then so is tomorrow and next year and so on and don't forget about yesterday and so on."
Nonsense! Tomorrow (and next year) is "in the future," not *present.* Yesterday is *no longer present.*
"Is" means present. "Will be" means future. "Has been" means past. Are you making up your own temporal vocabulary?
Robittybob1
7th March 2012 - 07:37 PM
QUOTE (mik+Mar 7 2012, 07:18 PM)
The present is the ongoing 'now,' not a "time period" however short.
"The future is not yet *present.* The past is not still *present.* What about this do you find difficult to understand?
You say:
"For if you say "Today" is the present then so is tomorrow and next year and so on and don't forget about yesterday and so on."
Nonsense! Tomorrow (and next year) is "in the future," not *present.* Yesterday is *no longer present.*
"Is" means present. "Will be" means future. "Has been" means past. Are you making up your own temporal vocabulary?

Look back a couple of posts it was you who said "When "tomorrow comes" it will be "today", the present." You said today is the present, not me but you.
mik
7th March 2012 - 10:39 PM
QUOTE (Robittybob1+Mar 7 2012, 07:37 PM)
Look back a couple of posts it was you who said "When "tomorrow comes" it will be "today", the present." You said today is the present, not me but you.


I don't see any contradiction in what I said, which you quoted.

Maybe I can clarify my meaning. Now **is** the present. When we say "today" we usually mean "the present day", as distinguished from the past ("yesterday") or the future ("tomorrow.") But "right now" is the ongoing moment with no time period or 'duration.' It is always now... all day long... always.
Robittybob1
7th March 2012 - 10:49 PM
QUOTE (mik+Mar 7 2012, 10:39 PM)

I don't see any contradiction in what I said, which you quoted.

Maybe I can clarify my meaning. Now **is** the present. When we say "today" we usually mean "the present day", as distinguished from the past ("yesterday") or the future ("tomorrow.") But "right now" is the ongoing moment with no time period or 'duration.' It is always now... all day long... always.

"It is always now... "

So everything happens in the "Now".

But not all things happen at once even though they all happen Now!

So it must be an always changing now (like a wave progates across the ocean).
hpdrdoom
8th March 2012 - 01:38 PM
How can you describe time ?
hpdrdoom
8th March 2012 - 03:12 PM
I think that when you went back in time you made a multiple copy of your self and you let the time to travel by being inside a "time capsule". Therefore you went back in time and saw your genuine copy. according to me there is no past scientifically there is only present and future that we make our self by making disorder in what you see.

*Note= here time according to me is the record of disorders that see around and we know that when did it happened.
Robittybob1
8th March 2012 - 05:14 PM
QUOTE (hpdrdoom+Mar 8 2012, 01:38 PM)
How can you describe time ?

I like the wave analogy. As the crest of the wave moves foward there are thing approaching the crest and things past the crest . Before, Now (The crest) and past, moving forward right across the bay.
mik
9th March 2012 - 05:37 PM
QUOTE (Robittybob1+Mar 7 2012, 10:49 PM)
"It is always now... "

So everything happens in the "Now".

But not all things happen at once even though they all happen Now!

So it must be an always changing now (like a wave progates across the ocean).

Yes, "it's always now." Now is the ongoing present, not a static so called 'moment in time' or 'snapshot', though the latter records a specific instant.

"So everything happens in the 'Now'." Everything *is happening now.* "The now" means the present, the present tense as in "is happening." This does not deny that things will happen in the future and that things have happened, which are now in the past.
So... no...
" not all things happen at once even though they all happen Now!"
... and, yes, the present is the " always changing now ."
Robittybob1
9th March 2012 - 05:47 PM
QUOTE (mik+Mar 9 2012, 05:37 PM)
Yes, "it's always now." Now is the ongoing present, not a static so called 'moment in time' or 'snapshot', though the latter records a specific instant.

"So everything happens in the 'Now'." Everything *is happening now.* "The now" means the present, the present tense as in "is happening." This does not deny that things will happen in the future and that things have happened, which are now in the past.
So... no...
" not all things happen at once even though they all happen Now!"
... and, yes, the present is the " always changing now ."

Not all "nows" are the same so each is a snapshot in time.
synthsin75
10th March 2012 - 01:01 AM
While it can be considered to be true that "everything" is always happening "now", physics distinguishes events which cannot be considered to all happen in the same now. Event A that causes event B cannot be said to occur in the same now, as this would violate causation. Physics, and even science in general, is primarily concerned with causes and effects. These do not exist without time.
mik
10th March 2012 - 05:43 PM
QUOTE (Robittybob1+Mar 9 2012, 05:47 PM)
Not all "nows" are the same so each is a snapshot in time.

Addressed to synthsin75 and Robittybob1,

Now is the present, everywhere, therefore there is no plural of now.
We all know that it takes sunlight 8+ minutes to reach earth, but *now is the present* both here and there... and, by extension, everywhere.

Relativity deals with who(frame of reference) sees what and when, so it speaks of my "now" being different than your "now" because of the distance between us (or between earth and sun.)
That works fine for calculations involving different frames of reference, but it doesn't make each locus in the cosmos have its own local "now," a different present depending on space between loci.
The "fabric of spacetime" is a *fabrication* used as a framework for calculations in relativity, but that does not make "it" an actual entity in the cosmos.
Space is still volume, however large, and time is still the concept of "that which elapses" as things move.
synthsin75
10th March 2012 - 06:24 PM
QUOTE (mik+Mar 10 2012, 11:43 AM)
Now is the present, everywhere, therefore there is no plural of now.

So are you claiming that there is no distinguishing present from past or future events? There is obviously a difference in the "now" perceived two seconds ago and the "now" currently perceived. This is the only sense in which all events cannot happen within the same now.

QUOTE
Relativity deals with who(frame of reference) sees what and when, so it speaks of my "now" being different than your "now" because of the distance between us (or between earth and sun.)


You don't seem to understand relativity. The relativity of simultaneity deals with observations from various reference frames. These rely on the finite speed of light, which will necessarily take different durations to reach different observers.

You should also note that the relativity of simultaneity doesn't violate causation, as one event which causes another will always be observed as happening before its effect, regardless of frame.
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