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Interstellar Travel and time taken for the trip. (No time dilation for the Earth)

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  Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-01 03:25 -0700
    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2017-09-01 13:23 +0200
    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) "Paul B. Andersen" <relativity@paulba.no> - 2017-09-01 14:15 +0200
      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-01 06:09 -0700
    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) rotchm <rotchm@gmail.com> - 2017-09-01 06:20 -0700
      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-01 07:05 -0700
      Re: Interstellar Travel and time taken for the trip. (No time  dilation for the Earth) The Starmaker <starmaker@ix.netcom.com> - 2017-09-01 12:40 -0700
        Re: Interstellar Travel and time taken for the trip. (No time   dilation for the Earth) The Starmaker <starmaker@ix.netcom.com> - 2017-09-02 12:19 -0700
    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Odd Bodkin <bodkinodd@gmail.com> - 2017-09-01 19:37 +0000
    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-02 03:26 +0200
      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) xxein1x1@gmail.com - 2017-09-02 22:34 -0700
        Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) xxein1x1@gmail.com - 2017-09-02 22:48 -0700
        Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-03 10:18 +0200
          Energy (was: Interstellar Travel and time taken for the trip. (No time dilation for the Earth)) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-03 15:52 +0200
            Re: Energy (was: Interstellar Travel and time taken for the trip. (No time dilation for the Earth)) Ethel Ocallaghan <unlgclo@awlwaac.ag> - 2017-09-03 13:56 +0000
              The problem of crackpots (was: Energy) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-03 17:32 +0200
      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-03 18:43 -0700
        Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-03 18:55 -0700
          Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-03 19:03 -0700
            Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-05 08:22 +0200
              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-04 23:32 -0700
              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 04:11 -0700
                Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Gary Harnagel <hitlong@yahoo.com> - 2017-09-05 05:06 -0700
                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-05 05:17 -0700
                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Gary Harnagel <hitlong@yahoo.com> - 2017-09-05 05:26 -0700
                      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Istrátora Metiku <untw@nwpovu.un> - 2017-09-06 12:42 +0000
                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 22:11 -0700
                Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-05 14:33 +0200
                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-06 00:33 +0200
                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 22:48 -0700
                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Istrátora Metiku <untw@nwpovu.un> - 2017-09-06 13:03 +0000
                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 22:46 -0700
                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-06 13:04 +0200
                      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-06 05:05 -0700
                        Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-06 05:25 -0700
                        Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-07 02:10 +0200
                          Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-06 20:40 -0700
                            Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-07 13:15 +0200
                              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-07 05:42 -0700
                              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-07 21:56 -0700
                              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-07 21:58 -0700
          Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-05 07:57 +0200
            Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-04 23:19 -0700
              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 03:38 -0700
                Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-05 04:52 -0700
                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 22:08 -0700
            Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 03:58 -0700
              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-05 14:22 +0200
            Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-05 14:03 +0200
          Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-05 08:26 +0200
            Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 04:12 -0700
        Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-04 06:42 +0200
          Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-04 05:35 -0700
            Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-04 21:49 +0200
              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-04 19:35 -0700
                Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-05 07:41 +0200
                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 03:53 -0700
                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-05 14:15 +0200
                      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 22:17 -0700
                        Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-06 12:44 +0200
                          Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-06 05:19 -0700
                            Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-06 15:34 +0200
                              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-06 08:53 -0700
                                Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-06 18:02 +0200
                                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-06 21:02 -0700
                                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-07 11:31 +0200
                                      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Erika Milling <kak@kiilwgil.lc> - 2017-09-07 15:46 +0000
                                      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-07 21:44 -0700
                            Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-06 16:01 +0200
                              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-06 07:11 -0700
                              Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-06 08:57 -0700
                                Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-06 09:01 -0700
                                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-07 02:25 +0200
                                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-06 20:49 -0700
                                      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-07 11:42 +0200
                                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-07 01:23 -0700
                                      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-07 02:01 -0700
                                Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Odd Bodkin <bodkinodd@gmail.com> - 2017-09-06 12:56 -0500
                                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) mlwozniak@wp.pl - 2017-09-06 12:44 -0700
                                  Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-06 20:36 -0700
                                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-07 12:04 +0200
                                    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Odd Bodkin <bodkinodd@gmail.com> - 2017-09-07 12:14 +0000
                                Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-06 20:12 +0200
    Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) bigal95210@gmail.com - 2017-09-05 15:48 -0700
      Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) gehan.ameresekere@gmail.com - 2017-09-05 22:49 -0700
        Re: Interstellar Travel and time taken for the trip. (No time dilation for the Earth) "Dono," <sa_ge@comcast.net> - 2017-09-07 07:32 -0700

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#431136

W dniu wtorek, 5 września 2017 08:23:02 UTC+2 użytkownik Thomas 'PointedEars' Lahn napisał:
> gehan.ameresekere@gmail.com wrote:
> 
> > So where is this "travelling into the future"?
> 
> If both the Earth clock and the starship clock show zero when you leave, and 
> the Earth clock shows 10 years but the starship clock shows only 8 years 
> when you return, how else would you as the traveler describe this situation 
> than that you traveled 2 years into the future?

As your bunch of idiots is too stupid to notice
that redefining "second" is not enough and "year"
has to be redefined too - the only valid 
description is: starship clock is wrong.

Of course whole situation is nothing more than
your sick imagination. We have GPS now and we can see
that real clocks indicate t'=t wiyh the precision
of an acceptable error. Just like clocks always
did.





> > Where is this "Time dilation?".


In the imagination of relativistic morons.

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#431146

On Tuesday, September 5, 2017 at 11:53:02 AM UTC+5:30, Thomas 'PointedEars' Lahn wrote:
> gehan.ameresekere@gmail.com wrote:
> 
> > So where is this "travelling into the future"?
> 
> If both the Earth clock and the starship clock show zero when you leave, and 
> the Earth clock shows 10 years but the starship clock shows only 8 years 
> when you return, how else would you as the traveler describe this situation 
> than that you traveled 2 years into the future?

Ahh this us such subtle point, human aging is quite variable, for example one can talk of chronological age and biological age, this is on Earth, for example. 
There is also the suggestion to 'hibernate' human beings so that they do not consume much food during the flight, and may not even age as fast. Now is this traveling into the future? (Example : Buck Rogers).

I would simply say that it took 10 years to get back, it is irrelevant what happened in the ship. That's the way I would describe it, anyway. I do not think sleeping and waking up constitutes traveling into the future, but that's my opinion.

> 
> > Where is this "Time dilation?".
> 
> If both the Earth clock and the starship clock show zero when the traveler 
> leaves, and the Earth clock shows 10 years but the starship clock shows only 
> 8 years when the traveler returns, how else would you as the person on Earth 
> describe this situation than that the traveler’s clock has been running 
> slower than your own during the round-trip, and that therefore time must have 
> passed slower for them than for you – must have been dilated?

That is one view. Take for example a swinging pendulum. In low gravity it will have a longer period of oscillation. Does this imply time dilation? I ma just not sure.

> 
> > It would be interesting to look at an experiment using video cameras and
> > video transmissions between the traveling probe and the Earth. No
> > mathematics will be used.
> 
> It will show to/on the person/video recorder on Earth that the clocks on the 
> starship/probe have been running slower than their own during the roundtrip; 
> and to/on the person/video recorder on the starship/probe that the Earth 
> clock has been running slower than their own, but jumped ahead (with the 
> numbers above, from 3.2 years to 6.8 years) when they decelerated and 
> reversed course.  Light travel time excluded, of course.
> 

I have to work this out, but the time dilation would be in effect event without a turn around?

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#431155

On Tuesday, September 5, 2017 at 5:12:02 AM UTC-6, gehan.am...@gmail.com wrote:
>
> On Tuesday, September 5, 2017 at 11:53:02 AM UTC+5:30, Thomas 'PointedEars' Lahn wrote:
> >
> > If both the Earth clock and the starship clock show zero when you leave,
> > and the Earth clock shows 10 years but the starship clock shows only 8
> > years when you return, how else would you as the traveler describe this
> > situation than that you traveled 2 years into the future?
> 
> Ahh this us such subtle point, human aging is quite variable, for example
> one can talk of chronological age and biological age, this is on Earth,
> for example.

"Biological aging" is not a good example of a clock.
 
> There is also the suggestion to 'hibernate' human beings so that they do
> not consume much food during the flight, and may not even age as fast.
> Now is this traveling into the future? (Example : Buck Rogers).

No.  Good clocks don't hibernate.

> I would simply say that it took 10 years to get back, it is irrelevant
> what happened in the ship. That's the way I would describe it, anyway.

Are you harking back to Newton's "absolute time"?  Don't you realize it
has been solidly refuted by all valid experimental evidence?

> I do not think sleeping and waking up constitutes traveling into the
> future, but that's my opinion.

THAT is a good opinion.

> Take for example a swinging pendulum. In low gravity it will have a longer
> period of oscillation. Does this imply time dilation? I ma just not sure.

It only implies that a pendulum clock is NOT a good clock.

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#431157

W dniu wtorek, 5 września 2017 14:06:05 UTC+2 użytkownik Gary Harnagel napisał:

> Are you harking back to Newton's "absolute time"?  Don't you realize it
> has been solidly refuted by all valid experimental evidence?

A lie, as expected from fanatic trash.

> > Take for example a swinging pendulum. In low gravity it will have a longer
> > period of oscillation. Does this imply time dilation? I ma just not sure.
> 
> It only implies that a pendulum clock is NOT a good clock.

On the other hand, clocks matching The Shit of great Einsteins
are good clocks because they match The Shit of great Einstein.
Well, they are proven unusable (GPS), but it doesn't prove
anything.

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#431161

On Tuesday, September 5, 2017 at 6:17:32 AM UTC-6, mlwo...@wp.pl wrote:
>
> W dniu wtorek, 5 września 2017 14:06:05 UTC+2 użytkownik Gary Harnagel napisał:
> >
> > Are you harking back to Newton's "absolute time"?  Don't you realize it
> > has been solidly refuted by all valid experimental evidence?
> 
> A lie, as expected from fanatic trash.

A lie, as expected from a moronically-disoriented incompetent Wozzie-boy.

> > It only implies that a pendulum clock is NOT a good clock.
> 
> On the other hand, clocks matching The Shit of great Einsteins
> are good clocks because they match The Shit of great Einstein.
> Well, they are proven unusable (GPS), but it doesn't prove
> anything.

Wozzie-boy does nothing but scream and yell obscenities.  His scatological
rants are without truthful content.

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#431322

Gary Harnagel wrote:

>> On the other hand, clocks matching The Shit of great Einsteins are good
>> clocks because they match The Shit of great Einstein.
>> Well, they are proven unusable (GPS), but it doesn't prove anything.
> 
> Wozzie-boy does nothing but scream and yell obscenities.  His
> scatological rants are without truthful content.

E scatological is something meaning _end-times_.

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#431288

On Tuesday, September 5, 2017 at 5:12:02 AM UTC-6, gehan.am...@gmail.com wrote: 
> I would simply say that it took 10 years to get back, it is irrelevant 
> what happened in the ship. That's the way I would describe it, anyway. 

On Tuesday, September 5, 2017 at 5:36:05 PM UTC+5:30, Gary Harnagel wrote:

> Are you harking back to Newton's "absolute time"?  Don't you realize it
> has been solidly refuted by all valid experimental evidence?
> 

Not really, just pointing out that a 'subjective' view of time allows for me to consider Earth time as 'real time'. We would not need clocks if we were clocks in the first place.

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#431162

gehan.ameresekere@gmail.com wrote:

> On Tuesday, September 5, 2017 at 11:53:02 AM UTC+5:30, Thomas
> 'PointedEars' Lahn wrote:
>> gehan.ameresekere@gmail.com wrote:
>> 
>> > So where is this "travelling into the future"?
>> 
>> If both the Earth clock and the starship clock show zero when you leave,
>> and the Earth clock shows 10 years but the starship clock shows only 8
>> years when you return, how else would you as the traveler describe this
>> situation than that you traveled 2 years into the future?
> 
> Ahh this us such subtle point, human aging is quite variable, [fallacy]

Once again, this is not about aging, not about biology.  It is about the 
*physics*, the passage of time.  Clocks show *that*.

> I would simply say that it took 10 years to get back, […]

But it did not.  The spaceship clock has ticket off 8 years on return, and 
it had ticked off 4 years when reaching the star.  So 4 years of starship 
time have passed on the way back.  Simple arithmetic.

> it is irrelevant what happened in the ship.

No, time is _not_ absolute.

> That's the way I would describe it, anyway.

Then you have forgotten far too much from your Astronomy 101 class and 
reading the book you recommended.

> I do not think sleeping and waking up constitutes traveling into the
> future, […]

It does not.  This has nothing (intrinsically) to do with biology.  Nature 
does not care whether there is a sleeping astronaut to begin with.

>> > Where is this "Time dilation?".
>> 
>> If both the Earth clock and the starship clock show zero when the
>> traveler leaves, and the Earth clock shows 10 years but the starship
>> clock shows only 8 years when the traveler returns, how else would you as
>> the person on Earth describe this situation than that the traveler’s
>> clock has been running slower than your own during the round-trip, and
>> that therefore time must have passed slower for them than for you – must
>> have been dilated?
> 
> That is one view. Take for example a swinging pendulum. In low gravity it
> will have a longer period of oscillation.

That depends on which observer you ask.  “In low gravity”, time also passes 
faster than “in high gravity” (gravitational time dilation).

> Does this imply time dilation?

No, but that time passes slower “in high gravity” than “in low gravity” 
does.

> I ma just not sure.

You are just confusing the issues.

>> > It would be interesting to look at an experiment using video cameras
>> > and video transmissions between the traveling probe and the Earth. No
>> > mathematics will be used.
>> It will show to/on the person/video recorder on Earth that the clocks on
>> the starship/probe have been running slower than their own during the
>> roundtrip; and to/on the person/video recorder on the starship/probe that
>> the Earth clock has been running slower than their own, but jumped ahead
>> (with the numbers above, from 3.2 years to 6.8 years) when they
>> decelerated and reversed course.  Light travel time excluded, of course.
> 
> I have to work this out, but the time dilation would be in effect event
> without a turn around?

Your question does not make sense.  Please rephrase it.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#431259

Thomas 'PointedEars' Lahn wrote:

> gehan.ameresekere@gmail.com wrote:
>> That is one view. Take for example a swinging pendulum. In low gravity it
>> will have a longer period of oscillation.
> 
> That depends on which observer you ask.  “In low gravity”, time also
> passes faster than “in high gravity” (gravitational time dilation).

I was curious if the effects could cancel, and since I have not gotten into 
the details of general relativity yet, I have looked it up:

<https://en.wikipedia.org/wiki/Gravitational_time_dilation>

<http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/gratim.html#c4>

<http://www.wolframalpha.com/input/?dataset=&i=gravitational+time+dilation&rawformassumption=%7B%22FS%22%7D+-%3E+%7B%7B%22TimeDilationGravitational%22,
+%22t%22%7D%7D&rawformassumption=%7B%22F%22,
+%22TimeDilationGravitational%22,
+%22to%22%7D+-%3E%221+year%22&rawformassumption=%7B%22F%22,
+%22TimeDilationGravitational%22,
+%22g%22%7D+-%3E%22g%22&rawformassumption=%7B%22F%22,
+%22TimeDilationGravitational%22,+%22r%22%7D+-%3E%2220+000+km%22>

It turns out that the gravitational time dilation on the surface of Earth 
compared to the terrestrial orbit is so small that one needs extra precision 
to even calculate it.  But a pendulum would not swing in orbit at all 
(unless it could bounce off from something) because it is in free fall.  
This clearly shows that the two things have nothing to do with each other.

It is a common fallacy (in fact, I now remember that I had already seen it 
from a crackpot in the German-speaking Usenet, and my rebuttal of it) to 
equate the swinging of a pendulum with the passage of time, because the 
pendulum is a mechanism that is designed for a *particular* gravitational 
acceleration/spacetime curvature.  A clock that probably would be less 
susceptible to such problems  would be a clock that uses a spring instead.  
Which I guess is one reason why *atomic* clocks have been used in the 
Hafele–Keating experiment, and are used aboard GPS/GNSS satellites, and not 
any kind of mechanic clocks.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#431292

On Wednesday, September 6, 2017 at 4:03:14 AM UTC+5:30, Thomas 'PointedEars' Lahn wrote:
> 
> It turns out that the gravitational time dilation on the surface of Earth 
> compared to the terrestrial orbit is so small that one needs extra precision 
> to even calculate it.  But a pendulum would not swing in orbit at all 
> (unless it could bounce off from something) because it is in free fall.  
> This clearly shows that the two things have nothing to do with each other.

I agree, Newtonian physics will predict a pendulum will swing slower in a lower gravitational field. It does not directly indicate the passage of time.

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#431324

Thomas 'PointedEars' Lahn wrote:

>> That depends on which observer you ask.  “In low gravity”, time also
>> passes faster than “in high gravity” (gravitational time dilation).
> 
> I was curious if the effects could cancel, and since I have not gotten
> into the details of general relativity yet, I have looked it up:

I have an answer to your question. Go to alt.support.autism and start a 
new thread asking "Where is everyone??".

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#431291

On Tuesday, September 5, 2017 at 6:03:41 PM UTC+5:30, Thomas 'PointedEars' Lahn wrote:
> gehan.ameresekere@gmail.com wrote:
> 
> > On Tuesday, September 5, 2017 at 11:53:02 AM UTC+5:30, Thomas
> > 'PointedEars' Lahn wrote:
> >> gehan.ameresekere@gmail.com wrote:
> >> 

> 
> > I would simply say that it took 10 years to get back, […]
> 
> But it did not.  The spaceship clock has ticket off 8 years on return, and 
> it had ticked off 4 years when reaching the star.  So 4 years of starship 
> time have passed on the way back.  Simple arithmetic.
> 

I was talking about the subjective view of time, which exists. Of course one cannot do physics using a subjective view but one can live with it if one chooses to.
 
> gehan.am...@gmail.com wrote: 
>> That is one view. Take for example a swinging pendulum. In low gravity it 
>> will have a longer period of oscillation. 
> 
> That depends on which observer you ask.  “In low gravity”, time also 
> passes faster than “in high gravity” (gravitational time dilation). 

The slowing of a pendulum due to gravity can be modelled using  Newtonian Physics only, I think that was my confusion. 

> >> It will show to/on the person/video recorder on Earth that the clocks on
> >> the starship/probe have been running slower than their own during the
> >> roundtrip; and to/on the person/video recorder on the starship/probe that
> >> the Earth clock has been running slower than their own, but jumped ahead
> >> (with the numbers above, from 3.2 years to 6.8 years) when they
> >> decelerated and reversed course.  Light travel time excluded, of course.
> > 

Would the twin have to decelerate and turn around, is time dilation occurring on the outward trip? I think you have somewhat answered this, but just to clarify.

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#431308

gehan.ameresekere@gmail.com wrote:

> On Tuesday, September 5, 2017 at 6:03:41 PM UTC+5:30, Thomas 'PointedEars'
> Lahn wrote:

Could you *please* change these two things?

>> gehan.ameresekere@gmail.com wrote:
>> > On Tuesday, September 5, 2017 at 11:53:02 AM UTC+5:30, Thomas
>> > 'PointedEars' Lahn wrote:
>> >> gehan.ameresekere@gmail.com wrote:
>> > I would simply say that it took 10 years to get back, […]
>> But it did not.  The spaceship clock has ticket off 8 years on return,
>> and it had ticked off 4 years when reaching the star.  So 4 years of
>> starship time have passed on the way back.  Simple arithmetic.
> 
> I was talking about the subjective view of time, which exists. Of course
> one cannot do physics using a subjective view but one can live with it if
> one chooses to.

But there is no absolute, preferred frame of reference.  The “subjective 
view of time” of the person who stays at home is not any more or any less 
valid than the “subjective view of time” of the traveler.  So the 
(subjective) statement of the traveler that the journey took them 8 years, 
but they have also traveled 2 years into the future (of the planet and the 
rest of the universe), is equally valid.

>> gehan.am...@gmail.com wrote:
>>> That is one view. Take for example a swinging pendulum. In low gravity
>>> it will have a longer period of oscillation.
>> 
>> That depends on which observer you ask.  “In low gravity”, time also
>> passes faster than “in high gravity” (gravitational time dilation).
> 
> The slowing of a pendulum due to gravity can be modelled using  Newtonian
> Physics only,

No.

> I think that was my confusion.

It was a part of it.
 
>> >> It will show to/on the person/video recorder on Earth that the clocks
>> >> on the starship/probe have been running slower than their own during
>> >> the roundtrip; and to/on the person/video recorder on the
>> >> starship/probe that the Earth clock has been running slower than their
>> >> own, but jumped ahead (with the numbers above, from 3.2 years to 6.8
>> >> years) when they decelerated and reversed course.  Light travel time 
>> >> excluded, of course.
> 
> Would the twin have to decelerate and turn around, is time dilation
> occurring on the outward trip? I think you have somewhat answered this,
> but just to clarify.

Both the home twin and the traveling twin would observe time passing slower 
in the other’s frame of reference than in their own, both on the outward and 
the return trip.

(But the traveling twin would *also* observe time jumping ahead in the 
other’s frame as they decelerate and turn around; the home twin would not 
observe any time jump.  Because *only* the traveling twin is switching 
between frames of reference by doing this.  That is the asymmetry here.)

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#431310

On Wednesday, September 6, 2017 at 4:34:23 PM UTC+5:30, Thomas 'PointedEars' Lahn wrote:

> 
> But there is no absolute, preferred frame of reference.  The “subjective 
> view of time” of the person who stays at home is not any more or any less 
> valid than the “subjective view of time” of the traveler.  So the 
> (subjective) statement of the traveler that the journey took them 8 years, 
> but they have also traveled 2 years into the future (of the planet and the 
> rest of the universe), is equally valid.
> 

Well then make it 'opinion of time' or maybe 'Earth- Bias'. It is sort of a prejudice which will emerge when we start travelling interstellar.

> > 
> > Would the twin have to decelerate and turn around, is time dilation
> > occurring on the outward trip? I think you have somewhat answered this,
> > but just to clarify.
> 
> Both the home twin and the traveling twin would observe time passing slower 
> in the other’s frame of reference than in their own, both on the outward and 
> the return trip.

I agree that this must be the case due to symmetry, and if there is no preferred frame of reference. 

> 
> (But the traveling twin would *also* observe time jumping ahead in the 
> other’s frame as they decelerate and turn around; the home twin would not 
> observe any time jump.  Because *only* the traveling twin is switching 
> between frames of reference by doing this.  That is the asymmetry here.)
> 

I just have to work this out, then.

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#431316

W dniu środa, 6 września 2017 14:05:45 UTC+2 użytkownik gehan.am...@gmail.com napisał:
> On Wednesday, September 6, 2017 at 4:34:23 PM UTC+5:30, Thomas 'PointedEars' Lahn wrote:
> 
> > 
> > But there is no absolute, preferred frame of reference.  The “subjective 
> > view of time” of the person who stays at home is not any more or any less 
> > valid than the “subjective view of time” of the traveler.  So the 
> > (subjective) statement of the traveler that the journey took them 8 years, 
> > but they have also traveled 2 years into the future (of the planet and the 
> > rest of the universe), is equally valid.
> > 
> 
> Well then make it 'opinion of time' or maybe 'Earth- Bias'. It is sort of a prejudice which will emerge when we start travelling interstellar.

Yes, yes! we all have to reject our prejudices and
follow the infinite wisdom of Great Guru! 


> > Both the home twin and the traveling twin would observe time passing slower 
> > in the other’s frame of reference than in their own, both on the outward and 
> > the return trip.
> 
> I agree that this must be the case due to symmetry, and if there is no preferred frame of reference. 

Yes, yes! Reject your preferrences! Choose the preferences
of Great Guru!

> > (But the traveling twin would *also* observe time jumping ahead in the 
> > other’s frame 

And when on a street, he will observe trees and buildings
running around him. Gurus said he will, his opinion doesn't
matter.

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#431411

gehan.ameresekere@gmail.com wrote:

> On Wednesday, September 6, 2017 at 4:34:23 PM UTC+5:30, Thomas
> 'PointedEars' Lahn wrote:
>> But there is no absolute, preferred frame of reference.  The “subjective
>> view of time” of the person who stays at home is not any more or any less
>> valid than the “subjective view of time” of the traveler.  So the
>> (subjective) statement of the traveler that the journey took them 8
>> years, but they have also traveled 2 years into the future (of the planet
>> and the rest of the universe), is equally valid.
> 
> Well then make it 'opinion of time' or maybe 'Earth- Bias'. It is sort of
> a prejudice which will emerge when we start travelling interstellar.

Highly doubtful.  Those people will have to know their science in order to 
survive.  Those guided by prejudice will not be aboard.

And think about it: Why should they care about Earth time at all?

The next star is about 4.3 light-years away; using conventional methods, a 
signal from Earth already takes 4.3 *years* to reach them, and the reply 
will arrive on Earth only after 4.3+ more *years*.  The spaceship will 
become their home instead, and those who enlist for that mission know that 
it is going to be a one-way trip.

On the other hand, suppose for the sake of argument that warp drive has been 
invented, and they are using it, then not only have they thousands of 
planets to choose from; time dilation will also become a non-issue because 
they are not actually traveling at high speeds relative to either of those 
planets – only the “warp bubble”, the enclosed region of spacetime, will.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#431421

On Thursday, September 7, 2017 at 5:40:19 AM UTC+5:30, Thomas 'PointedEars' Lahn wrote:
> 
> On the other hand, suppose for the sake of argument that warp drive has been 
> invented, and they are using it, then not only have they thousands of 
> planets to choose from; time dilation will also become a non-issue because 
> they are not actually traveling at high speeds relative to either of those 
> planets – only the “warp bubble”, the enclosed region of spacetime, will.
> 

Such a method of travel will make the twin paradox a thing of the past, if you excuse the pun.

Surely there will be some inconsistencies caused by a signal or a person arriving at a destination earlier than a beam of light would?

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#431452

gehan.ameresekere@gmail.com wrote:

> […] Thomas 'PointedEars' Lahn wrote:
>> [warp drive (FTL travel)]
> 
> Surely there will be some inconsistencies caused by a signal or a person
> arriving at a destination earlier than a beam of light would?

Related events would be perceived as a violation of causality.

Taylor & Wheeler 1992 [1] describes a situation where the good guys and the 
bad guys have treaty negotations on the bad guys’s home planet.  The good 
guys leave for their home planet afterwards.  While the good guys are 
traveling home at a relative speed slower than the speed of light, the bad 
guys start building a FTL starship.  When completed some years later, the 
good guys still being underway, the bad guys launch their starship, overtake 
the good guys and attack.  The Lorentz transformations then show that it 
appears to the good guys as if the bad guys have attacked before their FTL 
starship was built, and that they are coming from the future.

Science-fiction mentions those, for example, in the “Picard Maneuver” [2], 
where an attacker fires at an enemy ship, and is engaging warp drive (FTL) 
shortly after, thus appearing to the crew of the enemy ship to be in two 
places at once for a short time.

But IMHO those are not inconsistencies.  Merriam-Webster’s online dictionary 
defines an “inconsistency” to be “an instance of being inconsistent” [3], 
and “inconsistent” to be [4]

| lacking consistency: such as
| a :  not compatible with another fact or claim
| b :  containing incompatible elements
| c :  incoherent or illogical in thought or actions : changeable
| d :  not satisfiable by the same set of values for the unknowns

__________
[1] Taylor, E.F. & Wheeler, J.A. “Spacetime Physics”. ISBN 9780716723271.
    W. H. Freeman, 1992.
    <https://books.google.com/books/about/Spacetime_Physics.html?id=PDA8YcvMc_QC&redir_esc=y>

[2] “Star Trek: The Next Generation”. 1x09 “The Battle”.
    Paramount Pictures, 1987.
    <http://memory-alpha.wikia.com/wiki/The_Battle_(episode)>

[3] <https://www.merriam-webster.com/dictionary/inconsistency>
[4] <https://www.merriam-webster.com/dictionary/inconsistent>
-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#431462

W dniu czwartek, 7 września 2017 13:15:55 UTC+2 użytkownik Thomas 'PointedEars' Lahn napisał:

> Taylor & Wheeler 1992 [1] describes a situation where the good guys and the 
> bad guys have treaty negotations on the bad guys’s home planet.

JRR Tolkien has also described interesting cases.

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#431548

On Thursday, September 7, 2017 at 4:45:55 PM UTC+5:30, Thomas 'PointedEars' Lahn wrote:
> 
> Related events would be perceived as a violation of causality.
> 
> Taylor & Wheeler 1992 [1] describes a situation where the good guys and the 
> bad guys have treaty negotations on the bad guys’s home planet.  The good 
> guys leave for their home planet afterwards.  While the good guys are 
> traveling home at a relative speed slower than the speed of light, the bad 
> guys start building a FTL starship.  When completed some years later, the 
> good guys still being underway, the bad guys launch their starship, overtake 
> the good guys and attack.  The Lorentz transformations then show that it 
> appears to the good guys as if the bad guys have attacked before their FTL 
> starship was built, and that they are coming from the future.
> 
> 

I agree it is not an inconsistency. Of course at that point it depends if the good guys think FTL is possible or not. 

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