sullster

Please excuse me jumping in here to ask a question of the Relativity experts and not have to start a thread.

How was the time dilation equation derived?(The one with t' equaling t times the square root of 1 minus v2) I have been self educating about special relativity and my book is unclear, at least to me that is, about the derivation of this equation. I am an admittedly mathophobic but I am trying to learn physics as best as I can.

deltin9

You really did hurt my brain.


This may sound ludicrous but I’m working on a self-made theory wherein I some worth think that from movement commence time (I’m still working on it).Let me get your input about that.
In other words without any sort of movement there cannot be time, I think time is our way of identifying positions, events, etc. Because how can we know what time is if it’s never calibrated.
Lets image just for a moment that this is the beginning of a new universe nothing moves and it’s on pause mode:rolling: . Now what comes first? The space is there but what comes first between the time and movement. I think unless there is movement we do not know what time is, we cant possible tell what time is unless we calibrate it. Lets take a little mechanism of a machine for example, we wont know the efficiency of that little piece unless we test it and calibrate it to certain function rate that we want it to work by. But the calibration result is not going to derive it-self. Unless calibration is done.

eg. Lets say you have a 600bhp car park in you garage, you’ve never driven a car, bicycle, train, truck, nothing, no moving objects ever in your life, so you don’t possibly know what the rush and push of 600bhp car feels like but for you to know you have to drive the car so you know what it feels like then you can rate it and categories by saying 200bhp= fast 400bhp= faster and so on, but you cant arrive at the ratings without test driving the vehicle.

:thumbs: we should start another thread about space movement and time it might be interesting

deltin9

There are gases that borderlines and pass c speed of light from jupiter but also

http://www.quantumbiocommunication.c...e-reality.html
"In 1982, at the University of Paris, a research team led by physicist Alain Aspect discovered that under certain circumstances subatomic particles such as electrons are able to instantaneously communicate with one another regardless of the distance separating them; it does not matter whether they are ten feet or ten billion miles apart.
Somehow each particle always seems to know what the other is doing. This fact violates Einstein’s long-held tenet that no communication can travel faster than the speed of light. This means breaking the time barrier."

travc

Actually, this is pretty much the though experiment that leads to Relativity. You need to incorporate "how things are actually observed" as well, which is where light comes into it.

V-Bird

No, it merely shows the limit of present [consensus] thinking.

It is correct that no 'communication' is possible at FTL, but there is certainly the knotty problem of Gravitation which does.

During any exchange between atoms that involves light [EMR] there is a temporary 'loss' of its Gravitational force, both the gravitation element of the electron and the electron itself [which for that moment ceases to exist in our time frame, ie 'blinks out'] then move FTL, this is seen, by our only means of viewing it [light or EMR], as being the rather 'erratic' behaviour that is the Electron cloud.

As the FTL element rejoins the electron 'gravity' and 'mass' are felt, it is the physical opposite of the energy [termed as 'quanta'] that is recorded when the separation occurs.

Gravity [as we feel it] is the result of the return of the electron[s] with their gravitational force.

This is an essential part of Photon and other exchanges, many of which occur at FTL.

The above is not even vaguely accepted by everyone here...

epepke

Absolutely correct, and the direction of travel (as seen by subluminal observers) would be at right angles into the plane.

epepke

That's not the right time dilation equation.

The correct one is derived from the Pythagorean theorem. It's very simple. Let's say there's a spaceship going by, and someone shines a light from port to starboard. That would be, in the reference frame of the ship, a straight line. However, because you measure the ship as moving in the stern-to-bow direction, the light is going at an angle. You make a right triangle using this as the hypotenuse. Since light has to go at the same speed in all subluminal frames, and it's a longer path, time on the spaceship is going more slowly. The squares and square roots come from the Pythagorean theorem.

Jesse

Yes it is. The correct time dilation equation is , where t is the time interval measured in the clock's own rest frame, and t' is the time interval measured in the frame where the clock is moving at velocity v. I think you're describing the light clock argument, which gives the formula above. Here's a longer explanation of the light clock derivation:

http://www.kineticbooks.com/physics/...ity/10/sp.html

TNorthover

That I also find highly unlikely. With much more distant objects like galaxies I may have missed the result because it's too difficult to confirm the exact speed, that doesn't seem a likely issue within the solar system.

The other link seems very much on the kook side of science (and is trying to push a book besides). You can usually tell when an alleged physicist is veering towards kookdom when "consciousness" comes up.

Edit: I've looked up the actual results a little, and it seems that the crankiness is coming from the author of the book, not Alain Aspect. His work was simply quantum entanglement, which currently has very little effect on FTL and so on. At the moment we think there's no possible way to transmit anything, including information faster than light using it.

Edit2: To sum up entanglement, it allows you to entangle two particles next to each other to, say, have the same spin provided they're not disturbed too much. Then you can move them away from each other while this spin is still indetereminate by QM. Then you can measure the spin of the first particle, and if you quickly (in some sense) do the same to the other, you'll get the same result. Nothing travels faster than light though, and you can't use it to transmit information, because you can't force the spin of the first particle to be what you want (at least without being so intrusive as to break the entanglement).

Jesse

Entanglement can't be used to send information faster than light, but it's still pretty weird from a classical point of view--before it had been experimentally confirmed, Einstein dismissed it as "spooky action at a distance". Here was my explanation of it from another thread: