Strange Question: Time Difference between stars

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KLiK
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Message 1649042 - Posted: 4 Mar 2015, 8:25:40 UTC - in response to Message 1648543.  

Perhaps we should try Stardates ....

Star Trek

Chris, I know you were joking here. Star Trek totally ignored the problems of "spacetime" thru the use of a medium called subspace. Otherwise stardates would make no sense at all. Only on Star Trek could a starship leave earth for a two week voyage and return to earth with the same amount of time passing both on the starship and on mother earth.

Unfortunately that is one aspect of long distance space travel that most people don't grasp the reality of. A long duration space flight at near light speed would, for example, only take a couple years from the point of view of the crew while back on earth a much longer span of time, probably decades, will have passed. Meaning a returning crew would find a totally different earth situation and hopefully a new population to deal with.

In other words, space travel like we have seen in popular Sci Fi movies and TV isn't going to happen......EVER.

Not entirely true!

If you travel above speed of light, then the time dilatation form Lorenz euasions don't inflience you or your mother on Earth. Time passes equaly, only distance converge & move around.

To this date, Star trek is the only true & realistic movie...except for the Gravity & 2001/2010...


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Message 1649049 - Posted: 4 Mar 2015, 8:49:04 UTC - in response to Message 1649042.  


If you travel above speed of light

Too big "if" to reside in modern SETI@home science section. For now it belongs to "wishes and dreams" section mostly.
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Message 1649107 - Posted: 4 Mar 2015, 12:19:24 UTC - in response to Message 1649042.  

[quote][quote]
Not entirely true!

If you travel above speed of light, then the time dilatation form Lorenz euasions don't inflience you or your mother on Earth. Time passes equaly, only distance converge & move around.

To this date, Star trek is the only true & realistic movie...except for the Gravity & 2001/2010...

Where is your proof? No scientist I know of has ever proposed that ftl will behave that way. Star Trek is pure fantasy in these matters.
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Message 1649212 - Posted: 4 Mar 2015, 18:50:08 UTC - in response to Message 1649142.  
Last modified: 4 Mar 2015, 18:52:05 UTC


If you travel above speed of light

Too big "if" to reside in modern SETI@home science section. For now it belongs to "wishes and dreams" section mostly.

Questions from a person ignorant in this.

Worm Holes?

Doesn't Quantum Theory/Mechanics, allow the possibly that particles can be in two different places, at the same time?

Sorry if any Experts laugh at my ignorance.


The Universe has 11 dimensions, go figure..

http://en.wikipedia.org/wiki/Introduction_to_M-theory
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Message 1649219 - Posted: 4 Mar 2015, 18:59:07 UTC - in response to Message 1649212.  
Last modified: 4 Mar 2015, 19:11:22 UTC

Doesn't Quantum Theory/Mechanics, allow the possibly that particles can be in two different places, at the same time?


Actually they say that an electron's position is actually given by a probability distribution and in determining it's location actually "collapses the probability distribution function".

So: the electron could be anywhere and the cat could be dead or alive--you won't know until you look. I have trouble accepting that the cat is in both states and the electron is everywhere however.

It's sort of like this: if you have two piles of cards--one has all four aces only and the other is a normal deck containing all 52cards. If someone hands you an ace you won't know which deck it came from until you look. I claim that it could have come from either deck but in fact it came from only one and when you look you can determine which one it was.
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Message 1649467 - Posted: 5 Mar 2015, 7:18:02 UTC - in response to Message 1649107.  

[quote][quote]
Not entirely true!

If you travel above speed of light, then the time dilatation form Lorenz euasions don't inflience you or your mother on Earth. Time passes equaly, only distance converge & move around.

To this date, Star trek is the only true & realistic movie...except for the Gravity & 2001/2010...

Where is your proof? No scientist I know of has ever proposed that ftl will behave that way. Star Trek is pure fantasy in these matters.

Yes it did...Einstein in his teory of relativity...when he said that space-time can be wraped in a way to travel thorugh space, bending the fabric of space! Like some wormholes (which teoretically exists), you can travel wast distances in definite portion of time...so time is fixed, space moves...
Similar thing was proposed on Alcubierre drive...

So NO, I don't think Lorentz transformations work on speeds >= c! They only work till speed of light...

But it can give you "fanthom appearance", if you travel towards obeserver...somthing like this has been proposed in Picard manuever... ;)


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Message 1649538 - Posted: 5 Mar 2015, 13:00:22 UTC

Maybe time stays fixed to the person in the warp bubble, but not for everyone else. I have never read that time even stays fixed to those in transit.
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Message 1649662 - Posted: 5 Mar 2015, 19:36:44 UTC - in response to Message 1649644.  
Last modified: 5 Mar 2015, 19:38:24 UTC

Sigh ...................

In REALITY the cat is either dead or alive. It is simply in one or the other state at any one time.

The state does not change just because someone checks upon that state. That check will only confirm in which state it is at the time of the check. if the cat is dead, the state of it won't change in the future, however many extra checks are made. If the cat is found to be alive and the box is resealed, then the state of the cat continues to be an unknown until it is checked upon later.

But these so called clever cloggs say that to an outside observer it could be THEORETICALLY in either state at the SAME TIME. BOLLOX! The PROBABILITY of it being dead or alive is 50/50, UNTIL someone checks. Only someone in that box with the cat will know for sure if and when it died, or is still alive.

This stuff is just a load of old nonsense.

Would you let your daughter marry a theoretical physicist?


Yes. If only to have a decent conversation with my son in law:))
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Message 1649668 - Posted: 5 Mar 2015, 19:44:24 UTC - in response to Message 1649644.  
Last modified: 5 Mar 2015, 19:47:08 UTC

Would you let your daughter marry a theoretical physicist?

Yes probably :)

And I don't think I'd worry about it at all :) *pause to weigh up accuracy of expressed claim*

...the cat is either dead or alive...

erm... unless they had a cat... or if they asked to borrow a box, and then told me they were getting a cat...

I think under those circumstances I might pop in on them a bit more than usual :) ...as for trying to go down the route of "letting" her or not... yeah right :) Me and whose army precisely are we talking here? :)

edit: and what Julie just said makes a lot of sense too! :)
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Message 1649738 - Posted: 5 Mar 2015, 22:12:20 UTC - in response to Message 1649668.  
Last modified: 5 Mar 2015, 22:14:44 UTC

Would you let your daughter marry a theoretical physicist?

Yes probably :)

And I don't think I'd worry about it at all :) *pause to weigh up accuracy of expressed claim*

...the cat is either dead or alive...

erm... unless they had a cat... or if they asked to borrow a box, and then told me they were getting a cat...

I think under those circumstances I might pop in on them a bit more than usual :) ...as for trying to go down the route of "letting" her or not... yeah right :) Me and whose army precisely are we talking here? :)

edit: and what Julie just said makes a lot of sense too! :)

:))))))))))))

[edit]otoh... :))))))))))))))))))) + eternity (too tired to look up the sign and copy it, the eternity sign:)
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Message 1650107 - Posted: 6 Mar 2015, 22:17:56 UTC - in response to Message 1649788.  

∞ ∞ ∞ ∞ ∞ ∞ ∞

Hold the ALT key and type 236 on the num-lock keypad. Then hit space.

Note: This is for Windows.


ý <= I get this.
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Message 1650214 - Posted: 7 Mar 2015, 2:42:37 UTC - in response to Message 1650148.  

On a Mac it’s a single (modified) keystroke, option-5, like this: ∞.
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Message 1650281 - Posted: 7 Mar 2015, 11:36:45 UTC - in response to Message 1650240.  

∞ ∞ ∞ ∞ ∞ ∞ ∞

Hold the ALT key and type 236 on the num-lock keypad. Then hit space.

Note: This is for Windows.


ý <= I get this.

With the numbers on the right. Not above the keyboard.

KEEP Alt Key Depressed. Then press 236, Release the Alt Key, and then the space bar..

∞ ∞ ∞ ∞

Works on all my Windows 7 Computers.

Unless they are also in a different Universe. As I have been accused of.

:) :) :)


ý Nope, get this.. ý Strange...
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Message 1650293 - Posted: 7 Mar 2015, 12:35:11 UTC
Last modified: 7 Mar 2015, 12:44:01 UTC

Seems this thread gone too far offtopic.
But just to defend quantum theory from some vulgarizations expressed in this thread: no, it's not just "one or another until they look", it's real superposition of both states. To continue education on topic look description of experiments with electrons difraction for example. Interference picture exist if and only if the path of electron unknown. But that interference exists objectively, it's part of our reality that electron should "pass" both ways, not just our lack of knowledge about what way it passed.
The issues with non-local character of quantum theory are still unresolved. So it's the place where real physics and science fiction could intersect.
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Message 1650419 - Posted: 7 Mar 2015, 19:40:21 UTC - in response to Message 1650293.  

Seems this thread gone too far offtopic.
But just to defend quantum theory from some vulgarizations expressed in this thread: no, it's not just "one or another until they look", it's real superposition of both states. To continue education on topic look description of experiments with electrons difraction for example. Interference picture exist if and only if the path of electron unknown. But that interference exists objectively, it's part of our reality that electron should "pass" both ways, not just our lack of knowledge about what way it passed.
The issues with non-local character of quantum theory are still unresolved. So it's the place where real physics and science fiction could intersect.


:D It is Shabbat..
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Message 1651015 - Posted: 9 Mar 2015, 13:49:24 UTC - in response to Message 1650419.  
Last modified: 9 Mar 2015, 14:38:11 UTC

Subsequent work on the two-slit experiment has offered alternative information on why we see what we see.

Can you explain the idea of a "Superposition of two states" and why only two if you believe Feynman.

So: is it A and B ? or is it A or B ? I suggest it is the exclusive OR

Perhaps I can shed some light on the interaction between queries (information) what we call reality and probability: Since we have Schrodinger's cat, maybe we can also have:

DADDIO's KITTENS

My brother calls and says" My cat has just had two kittens would you like to have them?" I ask :"is one of them a Male ?" He says "yes". In this case the odds of the other being a male are 1/3. (yes that's correct). But: If I had asked "is the first one a male?" and got the same "Yes" answer; now the odds of the second being a male are 1/2.

So you see there is a strange subtlety in how we gather information and how it affects the likely-hood of what we find to be true in a given instance.
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Message 1651148 - Posted: 9 Mar 2015, 21:54:28 UTC - in response to Message 1651015.  

Subsequent work on the two-slit experiment has offered alternative information on why we see what we see.

Can you explain the idea of a "Superposition of two states" and why only two if you believe Feynman.


Any state can be represented as summation on full orto-normal basis states with corresponding weight coefficients.
It can be sum of some finite number of elements (if basis finite), it can be sum of infinite number of elements.
There are books that can help, for example this one: https://archive.org/details/QuantumMechanics_104
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