On Superluminal Propulsion

Originally posted by jkrog08
reply to post by Kruel

 

wikipedia.org/timedilation

That should clear it up for you,relativity is a very confusing subject.Stars light is observed from light from the past because the distance traveled takes even light time to arrive at Earth.BTW,what is that supposed to be on your avatar?

Lol nothing to clear up. That's ok though. It is a confusing subject.

The avatar is based on multiple points connected in two dimensions (but viewed from a 3D perspective). The 2nd dimensional connections are curved due to polarity.

reply to post by Kruel

You're right, at near light speed the passengers could get anywhere in their life time, they would zip across the galaxy nearly instantaneously. Even at a comfortable constant 1g acceleration, Sirius is only at 10 years on-board time, the Orion Nebula (1000 light years away), 30 years.

www.daviddarling.info...

reply to post by nablator


And Kruel...

I wouldn't say anywhere in their lifetime,since 60 years would still have passed inside the craft,and that's only to get to our nearest galaxy.Considering the Universe is around 156 billion lightyears wide(www.space.com...)I imagine even with the advantage of time dilation you would still die trying to get even half way across.

Not like any of this matters,hell you can go to Orion inwhat seems like 30 years,but you and any of your occupants will be the only people to see it,and when you get to your destination you might be disappointed to find out that due to stellar drift(en.wikipedia.org...) your star has moved!Plus considering 5 million years would have passed everywhere else,it is probably safe to assume that humans have either become extinct or long ago developed much faster ways to get there.

So again,traveling at the speed of light in real space is not a feasible option due to causality.Much more effort should be made in creating a ftl drive that takes the craft out of real space thus dodging causality in theory.Thanks for your comments!

you deserve star and flag + Applause for taking the time and effort into making this thread! Interesting stuff...

This should explain relativity better than what I failed to do in my OP…..

Relativity, and How it Affects Human Space Exploration and Travel
Some of the most complex theories in physics have to do with the study of relativity. The general principle of relativity states that in all frames of reference, the physical laws remain the same. Galileo Galilei described the principle of Galilean relativity in 1632, in his book Dialogue Concerning the Two Chief World Systems (Dialogo sopra i due massimi sistemi del mondo). In it, he theorized that in all "inertial frame of reference" (which is a frame of reference where Newton's first law of motion -which states that an object at rest will remain at rest and a moving object will continue moving at a constant speed unless acted on by a net force- holds true), the fundamental laws of physics all hold true. Once example of this is the fact that although the Earth is moving around the Sun, we cannot tell without looking at things that do not move like we do. Then, in 1908, Albert Einstein, with the help of Hendrik Lorentz and Henri Poincaré, published a paper called "On the Electrodynamics of Moving Bodies", in which he proposed the special theory of relativity. This dealt with measurements in inertial frames of reference. This theory is where the mass-energy equivalence equation (E=mc²) is derived. One of the many things the theory does is contradict the Newtonian notion of "absolute" or "universal" space and time, stating instead that observers moving differently perceive time and space differently. Another is show that c, the speed of light in a vacuum, is not just the speed that light travels in a vacuum, but a fundamental feature of the way that space and time interact and are joined as spacetime. This means that no particle with mass can travel at or faster than the speed of light. These two components of the special theory of relativity will greatly affect the future of human space exploration and travel. Space is big. Really big. This is the greatest problem with our exploration of space is that things are very far away, and our tools for exploration move very slowly. Voyager 1, launched September 5, 1977, and as of May 9th of this year had traveled over 15.89E12 meters (14.72 light-hours) from the sun, and that's with gravity-assisted speed boosts. Voyager 1 is expected to have enough power to communicate with Earth through 2025. Although it will not be able to communicate with us, Voyager will continue to travel due to the principle of inertia. But we will never know what Voyager encounters after it loses contact with us. At it's rate, a journey to the nearest star to the sun, Proxima Centauri, would take 72,000 years. It will be very difficult to actually explore space with the current technology. And even if we could keep probes transmitting for much longer the projects may never be able to take place because the cost would be hard to justify. Finding financial justification for a project that may not yield results for decades, centuries, even millennia, would be near impossible. Even on a smaller scale it is difficult to explore just our solar system, simply because of the length of time it takes to get probes anywhere. Just to get to Mars takes about six months. This also affects travel and colonization. If a colony on Mars were established, in the event that anything was needed from Earth, it would take six months for it to get there. So in order for space exploration and travel to be effective, we need to be able to go faster. But it is more than just technology that limits how fast we can go. Special relativity does that too. Special relativity shows that no particle with mass can travel at or faster than the speed of light. One of the reasons that faster-than-light motion is prohibited is casuality, or cause-and-effect. If two events (One and Two) occur simultaneously in a frame of reference, but are separated by space, there are frames of where one occurs before the two, and frames where the two occurs first. So if event one causes event two, there are frames of reference where the cause occurs before the effect. If faster-than-light motion could be obtained, one could send signals into one's own past, contradicting casuality. If casuality is to be preserved, matter or information cannot travel faster than light. So we cannot travel faster than light. But if there if we could find a way to travel at speeds closer to the light speed we would still have a problem eventually. Although speeds closer to the speed of light would make exploration and travel in our small section of space very effective and efficient, it still would make exploration and travel farther away from us hard. The closest star to the Sun, Proxima Centauri, is approximately 4.22 light-years away. With the best technology we currently have, nuclear pulse propulsion, it might be possible to reduce travel time to Proxima Centauri to a century or less. For humans, that's quite a while. The best possible candidate for a terrestrial planet outside our solar system is Gliese 581 d, which is about 20 light-years from the Sun. So even if someday we manage to travel any where close to the speed of light, it would still take over twenty years to travel to Gliese 581 d. If someday in the far future we would ever chose to send a manned mission to the planet, one would think that the crew members would age so much on the mission that it may not be possible. And that's where another consequence of the theory of special relativity comes in: time dilation. Time dilation is phenomenon associated with special relativity. Time dilation, which has been experimentally proven, shows that time passes differently for things moving at different speeds. This is often illustrated by a thought experiment called the "twin paradox". In it, there are a pair of twins. One twin gets on a space ship and makes a journey into space at a very high speed. The twin returns from the journey to find that he or she or has aged less than the other twin has. More time has passed for the Earthbound twin than for the traveling twin. Time dilation could make it possible to send manned missions far away from Earth without the crew members aging so much. Although the time on Earth would pass "normally", to the crew members, the journey would be much shorter. Missions to places many light-years away may mean that much time will have passed on Earth, but the crew members would not die of old age like one might think. Of course, in order for the time difference to be effective enough, the crew would have to be traveling extremely fast. With today's technology, humanity is very limited. Limited by space and time, by age, by death, by technological breakdown. But if we could develop a way to travel fast, closer to the speed of light, the limits may fall away, and the universe would lie open to us- we could explore and travel farther than the imagination. There is a beautiful universe just waiting to whisper its secrets in humanity's ear. All we have to do is move fast enough to hear them.

aerospacescholars.jsc.nasa.go v


[edit on 5/3/2009 by jkrog08]

reply to post by Kruel


Yes though,I should have specified further on time dilation.I believe it would only seem 'instant' to the traveler if the acceleration to c was instant,but if it was gradual acceleration the time would seem more like a year or two.And beings how no human could withstand the instant acceleration from 0 to 186,282.3 mps,and the time dilation for Earth bound observers this type of propulsion is not feasible IMO.

reply to post by Poet Of Deception



Hey,thanks for that,I am glad you liked it!

You might like my Astronomy 101 or On Parallel Universes thread as well.

Perhaps I skimmed the post too fast, then maybe not. If he covered this point, I apologize, but I long ago grew tired of Sagan-ish explanations for our limited understanding and outlook on physics. (He had an agenda, you know.) And, there are those that still work to misdirect our attention elsewhere than to the simpliest explanation for UFO star drives. People, the evidence is seen daily on Earth when our triangles and genuine UFOs defy gravity and mass as a common characteristic of their capabilities.

Basically, they are null-mass vehicles. That is not the same an anti-gravity. They cancel their entire mass.That done, they need little power to move within our atmosphere on cruising to their home star. It is a side step of physics just as simple as our aircraft which sidestep pure, rational (it would seem) physics by cheating with the utilization of air.

reply to post by Aliensun


Yea, I am aware of that supposed technology. You are referring to the Mercury-Plasma Ring on the TR-3B are you not? It rotates at 60,000 rpm and is pressurized at 250,000 atmospheres. It reduces mass by 89%, thus like you said-'side stepping physics'. Good point, and thanks for dropping by!

reply to post by LiquidLight


Ah, but the rules of the macro world don't apply to the micro.

Also to further my response I suggest you read this, which is the famous "EPR" arguments...

EPR Argument

reply topost by jkrog08



yes but as has also been discussed are we the 'Macro' or the 'Micro'?
ive always thought about the parralels between our so called macro-cosm and the micro-cosm that lies inside all of us like its own mini universe, what if we are some kind of micro' on a scale of being part of something altogether larger, then maybe the behaviour of our science when it comes to mimicking particles may work like that on a microscopic scale, hmmm??? could be possible in some dimension....

Ok, I have a question for you all. Assuming at least some of what we read is true, lets put things in perspective first. The earth travels about the sun which in turn travels about the center of the milky way galaxy, which in turn also travels through space as the universe continues to expand. Ok given all this motion going on as I sit here typing this, how fast might I really be moving through space-time, and yet not spill my coffee?

Since rotation is involved, I do understand that the speed and direction fluctuates. I'm just curious as I don't know the speed of motion for each of the bodies, nor am I all that familiar with the angular relationship of their paths either.

My point is, if I were able to somehow jump off this merry-go-round... how long before the next star comes along so's I can get back on the internet to check my email?

reply to post by peopleunit


I am not sure what you are asking? Are you simply asking the average speed of universal expansion or are you asking what would happen if you exit the Milky Way?

I was just wondering how fast I'm actually moving, and in what general direction. It feels like I'm standing still but I know that the earth, sun, galaxy and perhaps the entire universe are moving beneath my feet - taking me along for the ride.

So... how fast is this bus moving?

Relative to what ?

Astronomers believe the Milky Way is moving at approximately 630 km per second relative to the local co-moving frame of reference that moves with the Hubble flow.

en.wikipedia.org...