Theory of relativity  and the twin paradox: is the aging biological?
541187
Yes.  It means that for the twin that stayed on Earth, the time really passed for him, and for the twin who traveled, less time passed.\nThe older twin doesnt just "look" older, he really is older.  He really experience that time. And the younger twin really experienced less time passing.
360918
time is relative. perhaps you can use this example: two twin brothers which born in the same time, the first one live on the earth and the other one live in the spaceship outside the earth's atmosphere, for a several years. when the second one returns to earth, the age of the twin brother is not the same. the reason? it's relativity, einstein told about this long time ago.
435368
I think u could visit this website for the general relativity:\n\nhttp://archive.ncsa.uiuc.edu/Cyberia/NumRel/GenRelativity.html
443971
So far time dilation is possible in the forward direction. That is if YOU travel away from earth in a very fast spaceship near the speed of light then turn around and come back. The people on earth would age more then you have. YOUR clock would be different then those people on earth. It would be faster.\n\nGoing backward in time is still up there.\n\nThere are many experiments that prove this to be true. Atomic clocks capable of high accuracy are sync up. One is put on a plane and flown around the earth at high speeds for a long time. When the two clocks were compared later, they showed a difference, a very small difference but a difference none the less.\n\nTake a look at this website. There are plenty of other site out there.\n\nhttp://imagine.gsfc.nasa.gov/docs/ask_astro/answers/050225a.html\n\nInterestingly, if you did travel at the speed of light, you would be anywhere and everywhere all at once... WOW! That blows my mind.    :-)
280118
Not sure if this is the answer your looking for but this is the answer to the twin paradox.  \n\nThere is really no paradox.  The crucial factor overlooked is that in order for the two twins to get back together and discuss their beliefs, one of them must accelerate.  In so doing, the accelerating twin does not remain in the same inertial frame, but rather ends up in a frame heading back toward Earth.  An observer always in an inertial frame will observe relativistic effects in the usual way--moving objects contracted and moving clocks running slowly-- even if the object or clock he observes accelerates.  In order for the twins to ever get back together one much TURN.  By definition when you turn you accelerat even if your speed remains constant.  Its the acceleration that prevents a paradox.\n\nAs to why Einstein only got one nobel prize, short answer none of the established physisist liked him.  He was just a patent clerk who was messing up their nice neat notions of the universe.
876226
Visit this link for a good explanation:\n\nhttp://en.wikipedia.org/wiki/Theory_of_relativity
598949
Depends on your perspective.  As you travel closer and closer to the speed of light, time for you will seem to be normal, but you will see it speed up for others who are stationary.\n\nIf you are the one who is stationary, time will seem normal to you, but it will slow down for the one traveling.\n\nAn example - your twin has just been chosen to go on an interstellar trip.  Thankfully you're telepathic and can communicate over any distance.  As she speeds up, you will notice that there are longer and longer times between her transmissions to you, even though she says she'd contacting you at the same time every day.  And when she returns to earth 50 years later, you find she's only aged 10 years! (Robert Heinlein wrote a great novel about just this scenario - "Time for the Stars").\n\nScientists have proven this amazing fact in many experiments. They've put an atomic clock on a fast jet and flown it around the world.  When they returned, the clocks had different times than those on the ground.  But not by much - the clocks were between 50 and 270 nanoseconds different than their stationary counterparts - that's 50 billionths of a second.  Not much - but 500 mph is pretty slow compared to the speed of light.\n\nAnother way this is used in everyday life is the GPS satellites.  This navigation system has to take relativistic effects into account in it's transmission signals in order to get the high accuracy it's capable of. Every GPS satellite has an atomic clock aboard.  Because of the speed of the satellites, a ground observer will see them ticking slower than real time, so the signals have to be adjusted.\n\nTo answer your question - if you traveled around the world at 700 mph for a week, you'd be a few thousandths of a second younger than your friends who stayed behind.
527452
SIR elbert einsten because he is the great scietist of history. his theory of relativity is very exellent . when this world lost after some lack year then then this theory help us because in the future scientist go on new world in the space.these all thing posible when einstien theory says\nthat  for example a man  (age=18)who live on earth and one who(age=18) which goes in the universe with the speed of light after 50 years the age of man which who live on earth his age 65 year. and one which goes in the universe with speed of light his age is 35 years. tell me which scientist is genius.
271484
yeah, you get a bit off on a deep tangent towards the end there... but I don't think Einstein asserted anything more than the idea that time, space, and matter are related and not independant.  two systems of matter travelling in wildly different velocities relative to one another also have different processions of time and different masses, from the perspective of the other.  It only applies to things moving close to the speed of light- I think it's the Schroedinger Equation that covers the inter-relation.  But there's no real analogy to it in the observable world, unless you work at a particle accelerator, so I leave it to the doctorates of physics to debate.
225956
His definition is a little odd, and does not seem to follow from his example (which is more about motion than position on the earth).  Technically, his motion relative to stationary students would make time pass at a different rate according to all that Einstein stuff (though there's no way he could ever notice the tiny difference).  But that would be true without any reference to the earth and the sun.  Is he trying to make a different point -- that his days would be longer because the sun would set later for him because he is walking toward the west where the sun sets?  If so, he's right that his days (defined as revolving around the Earth's axis) would be longer, but that would not mean time was moving at a different speed for him; it would only mean that the sun would set a little later from his visual perspective -- just like you can gain or lose hours when you cross time zones in an airplane; you reset your watch, but that has nothing to do with the passage of time.  Unless you are defining time only by calendars and clocks and common agreement.
314759
Yes, it would be more accurate, but the calculations are much harder. Whether it is worth it depends on what you have to do with the information. One thing that happens is 'frame dragging', where a rotating mass drags along space and time with the rotation. We now have a probe in orbit around the earth to measure exactly this phenomenon.
1040099
I saw a lot of good answers out there that hit the answer pretty much on the head.  I only wanted to point out one minor mistake in what you wrote (which you probably won't run into in most freshman courses in relativity).  That the astronauts would actually be older than those who stayed on Earth.  The special relativity people were explaining was correct.  If you move => time slows down.  The thing is that gravity has a greater effect in slowing down clocks and the gravitational field you experience in orbit is weaker than on the surface of the Earth (obviously it won't matter though if you are flying around space at speeds near the speed of light, then the special relativity part becomes dominant over the general relativity i.e. gravity).
1063023
Don't you think that relativity dictates that those two things are the same?\nEdited my old answer after thinking-\nmy answer is:\nIt doesn't make a difference if I say I'm going 65 miles/hr or if I say everything else is and I'm going 0.  For all intents, purposes, and consequences, it's the same.  It's the same in this case, frame of reference is crucial in measurement, and so essentially, there is no difference in macro scale physics.\nGeneral theory of relativity wise, I'm still not sure about.  It seems like there might be serious consequences for this idea due to the speed of light/space relationship.  It also seems like I'm not really qualified to do those calculations, and the people who are could very well have already thought of this.  They are rather bright.\nSo my rating for viability of the idea is: (drum roll)\n23%
384756
Yup, relativity and qunatum mechanics work together nicely.  You'll need to account for the switch to using spacetime quantities instead of space and time quantities, and the fundemental equations get kind of hairy, but they still work out fine.
280555
Actually ... if you went back in time & killed your mother, you would cease to exist - therefore you would NOT be around to go back in time & kill your mother, so you would be born after all - THEN you would be able to go back in time to kill her, and you would cease to exist - therefore you would not be around to go back in time & kill your mother, so you would be born - and you would go back again, kill her, cease to exist ... it would go on forever! It's what's called a causality paradox. ; )
324066
149.658 lbs. ........ =D...... Thanks for the best choice thing.... Its pretty much all true... the twins paradox is theory.. humans have never been in space long enough to test it... look for a book... Black Holes by DK
933949
Theory of relativity.