Faster than light travel proved sort off

[GammaR4yBurst]

I think that mark gg is confusing FTL travel with length contraction and time dilation?

And mark gg, I agree with you that sometimes a fresh perspective from an outsider helps push science in new directions, but you can't just invent an idea in your head if it violates all the rules that have been tested and proven.

Science grows and evolves when new material is added to older ideas and reinforces testable and observable data, or shown to be false or unprovable and cast away.

These people you are calling "rude" are just trying to help you understand things that you just arent making sense with. They arent trying to make you mad, or hurt your feelings, they are just trying to put forth the truth that has been uncovered in the last few hundred years of science.

I am a lot like you, I lay in bed at night and think about things like this too. But just because I come up with an idea that makes sense in my head, doesn't mean that it is true. Its just not the way things work.

-Remember that this forum isn't a place where snobby people look down on you for being dumb, they are just people who spend their lives and careers studying the things that people like you and me have a slight curiosity for...

GRB

 

[schonovic]

A really good book to read about what occurs close to the speed of light is Steven Hawking's "On the shoulders of giants". it goes into great detail showing that it is completely impossible for matter to reach the speed of light. it's not just about "from this or that persons point of view", it is about nothing reaching the speed of light in whatever area of space-time you are in. this does not however discuss warping or tunneling through space-time, wormholes, etc...

 

[JordanL]

It seems that what mark_gg is positing, is that SR is only useful for predicting how other reference frames will perceive you. If you do not care about any reference frame at any time except for the one you are currently in, then you can travel arbitrarily "fast" from your own perspective... that would of course mean ignoring how everything else ages around you.

SR is useful if you believe you are not the only person in existence that actually exists. That is, SR is useful unless you subscribe to the "brain in a jar" idea, where everything in existence is a figment of your imagination, and nothing but your consciousness actually exists, in which case physics itself would be pretty pointless.

 

[mark_gg]

From the beginning I simply meant that you could travel a light year in less than a year.. from your perspective only.

This is true because (as I said) acceleration has no limit FROM YOUR PERSPECTIVE ONLY.

I don't know why this was so controversial, and what I said was just confirmed later into the conversation anyway, but with more detail.

I would like people of Physics to educate the public more on this, as it is possible therefore to travel very long distances very quickly FROM YOUR PERSPECTIVE only, and it' is only a naive lack of imagination to say this technology would never be invented.

An 'easy' experiment to perform is to get a rocket to go close to FTL (from the perspective of Earth) and see if time dilation does occur in the way expected (could just put a watch in the thing).

 

[PAllen]

From the beginning I simply meant that you could travel a light year in less than a year.. from your perspective only.

This is true because (as I said) acceleration has no limit FROM YOUR PERSPECTIVE ONLY.

I don't know why this was so controversial, and what I said was just confirmed later into the conversation anyway, but with more detail.

I would like people of Physics to educate the public more on this, as it is possible therefore to travel very long distances very quickly FROM YOUR PERSPECTIVE only, and it' is only a naive lack of imagination to say this technology would never be invented.

An 'easy' experiment to perform is to get a rocket to go close to FTL (from the perspective of Earth) and see if time dilation does occur in the way expected (could just put a watch in the thing).

Well, from your (rocket) you have not traveled a light year in less than a year. You have traveled something much less than a light year per year. What you have done is travel Earth's light year in less than a year of your time. See the difference? It is simply a case of mixing quantities from different frames - a pure and simple mistake.

A true statement, totally non-controversial, is to state you can reach some destination in a relatively short time as experienced by you.

As to an experiment, the fastest any macroscopic body has been accelerated to by any known technologies relative Earth (by earthlings) is .00005 c. You have quite a few orders of magnitude to beat all the world's technology by for your 'easy' experiment.

 

[HallsofIvy]

From the beginning I simply meant that you could travel a light year in less than a year.. from your perspective only.

This is true because (as I said) acceleration has no limit FROM YOUR PERSPECTIVE ONLY.

And peopel keep telling you you are wrong (and telling you why) and you keep responding "Oh, so I'm right!" That's really amusing!

You seem to be focusing on one part- the fact that, if you are moving at relativistic speed "time slows down". So if you are going at, say 90% the speed of light (relative to us) so that it takes you 1/.9= 1.11... years to go one light year (again relative to us), the time passed for you will only be (1.11)\sqrt{1- (.9)^2}= (1.11)(.436)= .484 years. You have crossed a light year in only .484 years and so have been going at 1/.484= 2.06 times the speed of light!

But that is wrong because you have neglected the contraction of distance at your relativisitic speed. Relative to you you will only have gone 1(.436)= .435 light years, not one light year and so will have been going at .435/.484= .90 times the speed of light.

That is what every one has been trying to tell you and you have been ignoring.

I don't know why this was so controversial, and what I said was just confirmed later into the conversation anyway, but with more detail.

I would like people of Physics to educate the public more on this, as it is possible therefore to travel very long distances very quickly FROM YOUR PERSPECTIVE only, and it' is only a naive lack of imagination to say this technology would never be invented.

An 'easy' experiment to perform is to get a rocket to go close to FTL (from the perspective of Earth) and see if time dilation does occur in the way expected (could just put a watch in the thing).

(That's already been done and it did occur "in the way expected".)

One more time: you are WRONG, WRONG, WRONG!

(I'll be interested to see how you interpret that as saying you are right!)

 

[Dale]

This is true because (as I said) acceleration has no limit FROM YOUR PERSPECTIVE ONLY.

It is false because if you are using someone else's distance and your own time that is neither "YOUR PERSPECTIVE ONLY" nor anybody else's perspective only.

Anyway, necroposting is irritating.

 

[Nugatory]

An 'easy' experiment to perform is to get a rocket to go close to FTL (from the perspective of Earth) and see if time dilation does occur in the way expected (could just put a watch in the thing). ...
In my head this sounds perfectly possible, and quite easy... so why hasn't it been done?

Just for grins, you might try calculating the amount of energy required to accelerate a 1 kg spaceship to maybe 90% of the speed of light... That will tell you why we haven't performed this experiment. (Edit - I'm not being sarcastic with that "just for grins" bit - it really is fun. Google for "relativistic baseball" to see what I mean )

However, we routinely accelerate subatomic particles to relativistic velocities and observe them in our lab (I've done it myself, with high-speed electrons) and have observed the predicted length contraction, time dilation, and "mass increase". There's also a pretty good summary of the experimental proof at https://www.physicsforums.com/showthread.php?t=229034.

 

[russ_watters]

From the beginning I simply meant that you could travel a light year in less than a year.. from your perspective only.

This is true because (as I said) acceleration has no limit FROM YOUR PERSPECTIVE ONLY.

I don't know why this was so controversial, and what I said was just confirmed later into the conversation anyway, but with more detail.

I would like people of Physics to educate the public more on this, as it is possible therefore to travel very long distances very quickly FROM YOUR PERSPECTIVE only, and it' is only a naive lack of imagination to say this technology would never be invented.

That is wrong. It would APPEAR to be true if you closed the windows of your spaceship and ignored the time dilation and length contraction going on around you and based the travel calculations on Newton's laws. But ignoring those things doesn't make them go away.

An 'easy' experiment to perform is to get a rocket to go close to FTL (from the perspective of Earth) and see if time dilation does occur in the way expected (could just put a watch in the thing).

And indeed, its been done many, many times including continuously on dozens of GPS satellites.

 

[ZapperZ]

From the beginning I simply meant that you could travel a light year in less than a year.. from your perspective only.

This is true because (as I said) acceleration has no limit FROM YOUR PERSPECTIVE ONLY.

I don't know why this was so controversial, and what I said was just confirmed later into the conversation anyway, but with more detail.

I would like people of Physics to educate the public more on this, as it is possible therefore to travel very long distances very quickly FROM YOUR PERSPECTIVE only, and it' is only a naive lack of imagination to say this technology would never be invented.

An 'easy' experiment to perform is to get a rocket to go close to FTL (from the perspective of Earth) and see if time dilation does occur in the way expected (could just put a watch in the thing).

May I suggest a change in attitude in the future? Rather than assume that you've found some new tests or think that you are exploring something that no physicists have ever even thought of (which makes a nasty assumption that we are THAT dumb), try just ASKING if such-and-such has been tested.

Time dilation experiment? There has been NUMEROUS examples of this. As has been pointed out, your GPS strongly depends on such time correction. And there are other direct, more stringent experiments on this:

http://www.nature.com/nphys/journal/v3/n12/abs/nphys778.html

There are many places on the web (and even a few threads in this forum) that have presented clear, easy lessons in relativity. However, on the part of the general public, you can't simply be lazy and expect to be spoon-fed and understand these things right away! Physics, as with mathematics, can't be understood simply from just reading things. It is an active lessons that requires calculations and repeated work for it to sink in! You can only understand things superficially without doing the necessary work. There is no short cut!

Zz.

 

[Darko M]

Well, I believe some day to come, the constancy of c would be demystified with reasonable evidence.

 

[HallsofIvy]

I just noticed, after reading Dale Spam's remark, that mark_gg had reposted to a thread two years old!

In any case, Darko M, what do you mean by "demystified"? I was not aware that "the constancy of c" was at all "mystified" and there is plenty of evidence.