i have another theory idea
everybody move in the speed of light

there is no such things as if a transport that can make us travel as fast or faster than light, then we will moving back in time
like the twin paradox which proposed by Einstein

my idea:
we see everything moving in the speed of light
when a car move faster than us, the the car is moving in a different velocity, but still travel in the speed of light. agree?
if we ever created a rocket that can move faster than light, then we see the rocket moving in the speed of light, but in the passenger in the rocket also see us moving in the speed of light.

just my idea........any1 can convince my idea is wrong?

This post has been edited by thken: Dec 19 2009, 01:18 AM

well, your title there is wrong :-)

huh? can you point it out?

the 'of' is wrongly spelled

What do you mean by that?? Everybody moves in the speed of light??

Quote
we see everything moving in the speed of light

I thought that we only see because the object reflects the wavelenght of a certain speed (balance of all wavelenght is the speed of light)

Hence if we're travelling at a speed of light?? Which I think is humanly impossible.. (Think of the G-Force we have endure first) Won't you think that we see... nothing???

No??

even when we idle, we move too, because the earth moves

if even the earth and whole solar system is moving in the universe, and we dont know the speed of it
therefore c=f(landa) can't be used when calculating object moving in the speed of light. no?

This post has been edited by thken: Dec 19 2009, 02:10 AM

Okay, what do you mean firstly by: everybody move in the speed of light?

Relativity doesn't allow you to add velocities in the sense that 0.75c + 0.75c = 1.5c, but it'll end up to be less than the speed of light, c instead.

what i mean here is everything in the universe travel in the speed of light

And how does this occur?

First of all, if you subscribes to relativity theory, things with mass can only approach the speed of light, can never be equal or exceeds it even both things are traveling in opposite direction.

Anyway, if you are referring to the twin paradox, where a sister (A) stays on earth and another (B) travel in a spaceship in near c speed, which one will stay younger? The answer is the one in spaceship.

From velocity perspective, if B is moving away from (A) by using A as a reference point, it is equal to A is moving away from B in opposite direction by using B as a reference point, why B is younger? Why not A? Is that your question?

I believe it is something to do with the accceralation impact and also the impact on the biological clock that B is experiencing as she is traveling in high speed.

Yea... Thanks for clarifying though...

But don't you think by making that statement you're saying that nothing can be calculated in terms of speed... For example, a proton traveling at 300kmph, if the earth is moving, and so is the universe, then it's not actually moving at 300kmph??

What I think speed of light means, it's that it's roughly 30,000km/sec which is comparaitve to an unmoving object... Lol... Not too sure how better can I define that...

And how do you assume that everything moves in the speed of light when you are not sure what speed are we moving at?? I do believe that no MASS can travel the speed of light... Only energy can... ( Do correct me if I'm wrong though)

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Added on December 19, 2009, 3:46 amWhat do you mean by staying younger though.. I do understand that she gains more time because of that but gaining more time, doesn't mean that she'll stay younger..

Be reminded that aging is not a passage of time, but an accumulation of biological events that occur over a period of time.

This post has been edited by hunter1012: Dec 19 2009, 03:47 AM

Staying younger means the total elapsed time experienced by B is shorter than A when they meet up again. If 10 years has passed for A on earth, B might only experienced 7 years traveling.

If B and A carried a digital date and clock system with them, the date and time of B would be shorter than A.

B is younger as she was within the timewarp environment that was different compared to A.

Here is one extract from wiki:

If we placed a living organism in a box ... one could arrange that the organism, after any arbitrary lengthy flight, could be returned to its original spot in a scarcely altered condition, while corresponding organisms which had remained in their original positions had already long since given way to new generations. For the moving organism the lengthy time of the journey was a mere instant, provided the motion took place with approximately the speed of light. (in Resnick and Halliday, 1992)

The idea of rocket travelling faster than light and going into the past, means we could very well send a nuclear warhead anywhere, at anytime into the pass. That sound dangerous...

Anyway, you can't reason speed of light without considering the effect of space-time continuum. If 2 person, one of them (person A) travel to Mars. With existing technology, he'll reach there in 18 months (June 2011). Then the other person (person B), travel at speed of light for 18 months, going many places and finally stop at Mars on June 2011. When these 2 person meet, both of them aged 18 months, neither is younger nor older. The reason because they arrive at the same space, on the same time we specified.

Next, person C, travel to Mars at speed of light in 4 minutes. Along the way, he look back at earth, to him, time has stopped on earth. As soon as he arrive at Mars, he took out a telescope and look at earth. He will discover that the earth look exactly the same as he left. Physically, he aged 4 mins. But at mars, in earth-time, he has not aged. A friend on earth, look through telescope, will see that, as if, he teleport to Mars instantly and has not aged at all.

Then he travel back to earth at light speed, took him 4 minutes. Similarly, he look at earth along the journey, and find that time pass twice as fast. Back on earth, physically he aged 4 minutes, but in earth time, he aged 8 minutes.

Aging still applied to the lightspeed traveler, only on relative s

On earth, despite if we travel at light speed, it makes no different and we will aged the same. Because earth locate on a very specific (and small) space-time continuum. Travelling beyond speed of light will only make us arrive at our location faster, still, neither are we going to be younger or neither can we go back in time. That is on earth scale.

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This post has been edited by marsalee: Nov 13 2010, 08:08 PM

Yeah. And your source of unlimited knowledge is wrong. Time do exist.

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This post has been edited by marsalee: Nov 13 2010, 08:09 PM

FYI, a hypothesis is classified as untrue when it is proven wrong, not the other way round. If time don't exist, how else did you grow old?

genetics?

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This post has been edited by marsalee: Nov 13 2010, 08:09 PM

How does genetic evolve? How does our body cell regrow? Evolution happen because time exist. It's like proving gravity. We say gravity exist because stuff fall onto ground. If time don't exist, stuff won't even fall. The sequence of event from day to day is the result of time.

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Added on December 21, 2009, 12:37 amWell, I'm just giving a suggestion to your hypothesis, "time does not exist". In order to make your hypothesis true, you need to prove that time does not exist. I'm not judging your unlimited limited knowledge whatsoever.

This post has been edited by Aurora: Dec 21 2009, 12:37 AM

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This post has been edited by marsalee: Nov 13 2010, 08:10 PM

and what, pray tell, will you call the passing of one moment to the next?

the problem is simple: it's all relative.

rule: the closer u move to the speed of light, the slower time passes for u.

u wont notice time moving faster or slower until u compare it with something that moves slower than u. lets say u have a twin brother, and he stayed behind on earth while u go traveling near the speed of light. when u return lets say 10 years later earth time, he would've aged 10 years (obviously), but u would have aged perhaps only 5 years (depending on how close u were to the speed of light).

but if everybody is moving at the speed of light, then there's no difference in age. u will still perceive time just as u are right now.

Strange.

Why do you compare speed of life with age?

"lets say u have a twin brother, and he stayed behind on earth while u go traveling near the speed of light. when u return lets say 10 years later earth time, he would've aged 10 years (obviously), but u would have aged perhaps only 5 years (depending on how close u were to the speed of light)."

i dont understand this statement. Let say If i travel the speed of light. It only take me to certain place(A) much faster that the light. But the time I travel to A will determine my age, not the speed of light.

For example: If i travel to sun in 1 minute. Earth can only see after 3-4 minutes. By that time, I'm already back to Earth. What earth saw was my past (2 minute ago) but present I'm still 3minute older (when earth see me).

Am I right or wrong?

This post has been edited by 100n: Dec 21 2009, 05:27 PM

[X] wrong knowledge

1. theory of relativity state that the closer you are to speed of light, the slower your "time" is relatively. IE. if you travel for 10 minutes at speed close to c, then stop, 10 minutes of your time has passed. however, 10 years may have passed for someone at a slower speed.

2. your example makes you to be traveling at speed higher than c, (you round trip earth-sun in 2 minute, when light takes 4 minutes - actually around 8 would be closer) which is at current theory, impossible.

I still dont understant this statement:

1. theory of relativity state that the closer you are to speed of light, the slower your "time" is relatively. IE. if you travel for 10 minutes at speed close to c, then stop, 10 minutes of your time has passed. however, 10 years may have passed for someone at a slower speed.

You mean like this example?

If you got in a rocket ship and accelerated you could go what seems infinitely fast to you. You could travel to a star 100 light years away and get they by lunch, turn around, and get back to Earth the same day. But you will find that everyone else is 200 years (and one day) older than you are. From their perspective, you were traveling very close to the speed of light and it take 200 years for light to get to that star and back. But to you, it was only a day. Your aging slowed down because you move forward through time faster. What you observe as linear acceleration in space that obeys Newton's laws, isn't what really happens. You start out accelerating in space but as you gain speed you start accelerating through time instead. You can only move at the speed of light in space, but can move infinitely fast through time.

This post has been edited by 100n: Dec 21 2009, 06:04 PM

I think lin00b is saying that, if you move close to the speed of light, even though you may perceive that your time passes like normal, those who are not traveling at your speed experience the time to be much longer. One minute for you while traveling close to the speed of light is equivalent to 1 year for those who are traveling through time at the regular speed.

Thats what I understand from lin00bs example.

This post has been edited by Mesosmagnet: Dec 21 2009, 06:13 PM

You'll be dead by then.

The impact that happens on that can nv be sustain by a normal human being.

Only immortals can do that probably. I guess u'll have to refer to some of the living beings in asylum/nuthouse to get that question answered.

no, you cannot travel faster than light. so if you do want to go to someplace 100 light years away, it will never be faster than 100 years to you. and to the observer at earth, a far longer time has passed.

your aging does not slow down. you'll still age 100 years. but your 100 years is a lot longer than the observer's 100 years.

what mesomagnet says.

Remember the phrase "Never say never".

Who sez you can never travel at the speed of light or even faster than that? There are still many scientific unknowns in this universe that will (hopefully) be uncovered in the future.

True that at the moment you can't travel at the speed of light because based on CURRENT scientific knowledge, you'll be squashed at the back of your nice spaceship wall if you go "lightspeed" in an instant. However, that's based on CURRENT scientific knowledge. What if somebody uncovered a way to warp space, fold space, enter subspace, enter wormhole, abolish inertia or what not, where mass would not be a factor? Never say never.

The world was once believed to be squared (where if you travel far enough, you'll drop off the face of the earth!) but finally realized to be rounded.
The world was once the centre of the galaxy where everything revolves around it until somebody proved otherwise.
Humans never thought they could fly until the Wright brothers did it.
Newton & Einstein (to name a few) discovered many remarkable things that humans thought not possible.

The sky is the limit. Just that to travel at the speed of light won't probably be in my in lifetime....

Note : Yeah, I see too much movies, read too much sci-fi books and play too many games......

I believe watching more sci-fi could probably uncover the possibilities towards the impossibilities.Perhaps one day , u might even stumble onto some secret sites from googling that provide findings upon using fingers wars to warp into the 8th dimension XD.

So far my brain or my knowledge towards the unknown scientific realms is limited XD. I hope that in my life, someone could uncover how to travel in the speed of light. So that the dude on a bike could not write me a speeding ticket on the highway.

mesosmagnet and lin00b have explained my argument.

the issue brought forward by TS spawned off from the theory of the younger twin brother. but actually it's just a confusion. the twin brother does not "get younger" than the other one. he just experiences time much slower.

it doesnt mean if u travel faster than light, u'll reverse aging .

[X] wrong concept

1. "squashing" is due to acceleration, not velocity

2. warping/ folding/ hyper-space/ wormhole/ whatever sci-fi tech does not break lightspeed barrier even though it may allow you to go 100 light year away in 1 day. its a different concept.

3. and you are looking at this in a different context. the discussion is based on current scientific laws and theories; and current theory puts a boundary at light speed and have some explanation of what happens then. if you want to bring sci-fi and "never know the future" into this, this is probably not the correct forum for you.

This post has been edited by lin00b: Dec 21 2009, 08:36 PM

[?] ??

1. Going from zero to lightspeed is not acceleration? Then what is it called? Velocity?

2. Lightspeed just mean 300k km/s. Does it mean that you can only call it lightspeed if you use conventional rockets and not some other way? If somebody can travel more than 300k km/s using some other method, it is not breaking the lightspeed barrier? Or is lightspeed barrier just solely reserved for the theory of relativity?

3) Yes, current scientific laws and theories puts a boundary at light speed. I did state that fact "CURRENT scientific knowledge". I guess it also includes current rocket technology and not "never know the future" propulsion technology. If that is the case, why discuss about the speed of light when a rocket can only go a fraction of the speed of light? If you want to say "IF you can travel at near the speed of light", that is about the future, no? Based on current technology, it is an impossible "if".

What I'm saying is, there are probably some unknown theories in the future that either improve or disprove this theory, enabling a work around to the lightspeed barrier.

Better get back to my sci-fi games.......

[exit forum]

This post has been edited by kmarc: Dec 21 2009, 09:32 PM

1. discussion is on what happens when you travel at/near light speed. not accelerating to light speed.

2. yes, traveling at a rate of 300km/s; all the other sci-fi stuff deals with creating a shorter pathway to get from point A to point B. but whether you travel at traditional path, or at shortcut you still cant exceed 300km/s.

ie. you travel at trunk road from perlis to jb vs you travel by PLUS. you may reach faster by PLUS, but your car maximum velocity stay the same.

3. rocket is current implementation limitation, current theoretical limitation is light speed, and we are discussing what happens at/near that speed. FTL is currently theoretically impossible, therefore not in discussion.

future theory may/may not be FTL, but in the context of this discussion, it is irrelevant.

2. the time dilation effect (as discussed in this thread) only occurs when u go through conventional means - accelerating from zero to lightspeed or beyond. space fold, jump, teleportation, wormhole etc is faster than light, but it doesnt involve acceleration. hence time dilation wont occur in such situations. it doesnt even break the lightspeed barrier.

but a different time perception does occur. lets say ur departure from earth was celebrated by fireworks. u use a gateway to travel to another point 10 light years away. the journey took 1 day. at ur destination, u look up earth using a telescope, but only sees the earth 10 years ago. for u to see ur own fireworks celebrating ur departure, u gotta wait another 10 years.

this is not time travel.

1. I was replying to your quote "Squashing is due to acceleration, not velocity". I meant that you get squashed if you go for zero to lightspeed, not get squashed when you travel at a constant speed.

2. (For discussion sake) Not all sci-fi stuff deals with creating a shorter pathway from A to B. Hypothetically, if you could create a bubble where only your ship and it's surrounding space is confined, you could move at light speed AND be seen to move at 300k km/s. However, you and the space around you are still stationary in one place while the bubble is moving at light speed. Of course, this is hypothetical and sci-fi.

3. I was just responding to your answers of my "wrong" concepts. FTL is currently theoretically impossible and therefore not in discussion but so is speeding along at/near that speed.

Corrections:

kmarc

You appear to be shorter in length if you move at some constant velocity relative to an observer


Moving close to the speed of light relative to some observer is not theoretically impossible. FTL currently is theoretically impossible

azarimy:

Not really; to make this clear, we label the twin brothers [1] and [2], [1] being the 'stationary' observer, and [2] being the person on the rocket flying off at some velocity

To [1], time goes by slower for [2]. But here's the important point, if [2] looked at [1], he would also see that time goes by slower for [1]. It's purely symmetrical because they're moving at the same velocity (well, excepting the +/-) relative to each other.

This post has been edited by bgeh: Dec 21 2009, 10:34 PM

No, what i meant is that if you accelerate from zero to lightspeed in say 1 second, the acceleration will squash you on the back wall of your spaceship.

"Moving close to the speed of light relative to some observer is not theoretically impossible. Faster-than-light travel currently is theoretically impossible"

Really?
http://www.bis-spaceflight.com/sitesia.asp...ge/1539/l/en-gb

To them, it is also not theoretically impossible.....

This post has been edited by kmarc: Dec 21 2009, 10:51 PM

That's general relativity, and something that I'm not qualified to discuss, but it seems that they're discussing a method to 'increase the speed of light' in some region of space by introducing a new metric (a perfectly fine thing to do)

Yes, but that's irrelevant. You still appear squashed if you move at a constant speed relative to an observer in special relativity.

Here, let's introduce stranger metrics in General Relativity: Godel metric
http://en.wikipedia.org/wiki/G%C3%B6del_metric

Travelling backwards in time using this metric isn't a problem at all; in fact time is probably an ill defined concept using this metric. The important point is to realise whether this metric is suitable to describe our Universe, and while I don't know enough about GR, I'd suspect the same applies to the link you posted.

No no. I meant literally get squashed into a pulp and not "appear squashed to an observer".

Errrmmmm.... I'm not qualified either.....

Sure, except that to any observer, if you're truly moving at the speed of light, your length will be exactly zero. Your original statement was:


But you do look squashed to any person observing you, even when you travel at a constant speed, this time, being the speed of light.

Agreed (based on current theories).

This post has been edited by kmarc: Dec 21 2009, 11:04 PM

that's what i said.

my point, relating to TS, is that they dont get younger. meaning age was not reversed. if u depart at 20 years old, u will not get back at 19 years old. moving at or near lightspeed is not the fountain of youth .

Future theories might not make it true either; in fact it might end up being an impossibility

Else it'll bring up the question: Why haven't we seen anyone from the future yet?

Note: In the initial statement, I said that FTL is a theoretical impossibility. I said this in the context of special relativity, where an inspection of the equation for the momentum of a particle in special relativity would give contradictions if you allowed a particle with mass to travel at the speed of light, i.e. it is impossible to take an object with mass, travelling at less than the speed of light relative to an observer, and then accelerating it to the speed of light, and hence you can't expect such an object to ever travel faster than light, since it can never pass the speed of light in the first place. There was no General Relativity brought into the discussion at all.

Note 2: I did more reading; the metric introduced by Alcubierre doesn't allow for FTL travel either, or travelling at the speed of light for particles with mass.

This post has been edited by bgeh: Dec 22 2009, 04:36 AM

Errr... the "Time directive" maybe? They are here but invisible maybe? Haha... more sci-fi.....

Yes, FTL is theoretically impossible based on current theories. I have no arguments with that. However, my argument is, why should FTL be limited to current theories? As I said earlier, faster than light travel just means you travel at >300k km/s by whichever means possible. If you could travel at 300k km/s in your "bubble" when the bubble is doing the "travelling" but your spaceship and the space within the bubble is stationery (and time is travelling at normal speeds), doesn't a stationery observer outside the bubble with his ADVANCED sensor see it as travelling at the speed of light from point A to B? Your spaceship and the immediate surrounding space would not violate Einstein's theory because it is stationary. The bubble doesn't have any mass because it is a field. No current theories are violated.

But oops, I guess this thread is about FTL travel based only on current theories and other future possibilities are not relevant. But double oops, trying to achieve maybe HALF FTL speeds are also future possibilities...... If we can't even achieve those speeds AND observe it, it is also irrelevant to discuss about time dilatation and time paradox and what not, no?

Ok ok. This thread is about travelling near or at speed of light based on current theories/propulsion technology which SAYS that it can't be done and other theories/future possibilities are irrelevant. I understand.

This post has been edited by kmarc: Dec 22 2009, 07:33 AM

As to your question, I'm not able to provide an answer - haven't done GR yet [it depends whether the axioms of SR do generalise naturally into GR - from this first look at this metric, it doesn't seem to]

It is also possible that I am your mother/father/grandfather. Have you considered that possibility yet? Or that everything that happens in the universe is actually due to fairies. Or that angels move objects in such a mathematical manner as to be able to be described by our current theories, and they might choose to change it anytime to 'suit' any other theory available.

What I'm trying to get at you is that, sure, anything's possible, but most 'possibilities', when tested, are shown not to occur. It was once thought that atoms were knots in the ether, but that was shown to be wrong. Let your imagination flourish, but I'd advise you not to think that possibility means inevitability, which is what you seem to be implying here. Not all science fiction will turn out to be true.

Or to use your example: Everyone thought the Earth was flat, and then they found it was a sphere. Well, why couldn't it be hyperbolic? Why couldn't it be a Klein bottle? Why couldn't it be a torus? Why couldn't it be various other shapes? - they're all possibilities. Sure, speculate all you want by assuming it's some possibility x, but it is not inevitable that your assumption is correct. But yes, if you indeed want to discuss time travel, and have to assume one of that, go ahead, but always be aware that it depends heavily on the assumption, which may turn out to be false after all

Now, what theory do you propose then, that has physical basis in our universe? (note: GR describes a set of universes, that certain solutions exist with interesting properties, e.g. wormholes, doesn't imply they exist in our universe) That's the big thing distinguishing science from science fiction, which seems to just take a problem, and proposes a miracle solution, and builds something upon it. Fair enough if they want to make stories out of it. But these miraculous solutions may turn out to be completely untrue, which is a more general point I'm trying to make here, and which is why I've been posting in this bloody thread so much

Yes, in a sense I'm saying they're irrelevant, because the existence of such a theory hasn't been shown yet, and even if it exists, FTL (we're making the assumption here that FTL means time travel - this might not be true either) might never be possible in all these theories, which is the point I'm trying to get at here really, and there are reasons for that, for one, causality, and wrecks the idea of entropy, mass-energy conservation, etc, etc... (again, assuming FTL does mean time travel, backwards). Sure these concepts might end up being replaced in the end, but the strength of a new scientific theory is that it is able to explain all previous phenomena explained by the scientific theory it succeeds, and be able to describe something new that the previous theory wasn't able to, i.e. it would still have to explain how those concepts I put up above still 'work' within its new framework.

This post has been edited by bgeh: Dec 22 2009, 10:05 AM

What u guys england2 ah?

shhhh... orang tua2 nak berborak.

dok tepi.

I think you have confused the points of information moving at the speed of light with things physically moving at the speed of light. When we see things, we see them as they are when light has left their surface. That absolutely doesn't equate with things moving at the speed of light. That's like saying when you hear your friend's voice as he shouts to you from the opposite building, it means he's traveling at the speed of sound!

Taking your example, when we see a car moving faster than us, we know he's faster because of his relative speed. If we measure his speed to be 20km/h faster than us, it could mean he's accelerated 20km/h ahead of us or we have just hit the brakes and slowed by 20km/h with respect to the car next to us. If we measure based on a fixed frame of reference, then we'll know for sure who's speeding up and who's slowing down. That's one of the basic points of relativity.

We do these measurements based on visual observations, or lasers, or radio waves, because EM waves are the fastest things we can use. So we compare our speeds based on the traffic light behind us. The sight of the lights arrive to us at the speed of light. We're using 'c' as the scale for our ruler.

When we travel at the speed of light, time doesn't move backwards. Time stops. Mathematically speaking. Time "stops" because when we move at the speed of light, what do see at our reference point? We'll be seeing the same image, because successive images can't catch up with us. We're moving at the same speed as that bit of information (that's traveling at 'c') that we're using as a ruler to measure our time and speed. For example, if we move at 'c' away from a stopwatch, can we see the stopwatch counting up? We'll only see the same signal that left the clock the instance we hit the speed of light, because the subsequent signals can't reach us. Hence, we see the stopwatch "frozen", and time has "stopped". But, the clock on our ship will continue running! Time is running on the moving frame, but time appears to have stopped outside of the moving frame.

Now, if we move faster than light (if we could), what would happen? We would be outrunning the signals from the external clock. We'll start to pick up the signals that had left earlier. We'll see the numbers that came out earlier, and it would look like the clock is reversing, because we're outrunning the speed of the information transmission. BUT, the clock on our ship will still be running forward, and we're still measuring time!

Outside of our reference frame, nothing has changed. If we were to stop our engines, we won't be in the past, we'll still be in the present/future (i.e. a few hours after the flight started) because, we didn't gain any time. As we slow down, the signals start to reach us again. At first, compressed. And then, it'll space out again in 'normal' time i.e. the one-second ticks match up to the rate of the clock on the rocket ship. It'll be compressed because of the wavelength shift of crossing between superluminal back to subluminal speeds. More likely than not, the information in between is missing and we'll just see the jump of a few missing seconds.

So, whether we're moving close to the speed of light, at the speed of light or faster than the speed of light, we're ageing normally within our ship. It's just that time looks different when we compare it with the external reference frame.

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Added on December 22, 2009, 2:38 pmWhen moving close to the speed of light, we see objects "squashed" mainly not because they have physically shortened, but because the light from that object has blue shifted. Not only would it look shorter (because the wavelength has compressed), its colour will also shift towards the blue end of the spectrum. This shortening or lorentz contraction is mathematically calculated based on the difference between your velocity and the speed of light, based on how light waves reaching a relativistic observer would compress.

Some would say that you'll physically compress as well, which is a logical extension of the fact that the fundamental forces holding atoms together propagate at the speed of light, so when we're going relativistic, these forces get blue-shifted and atomic structures get contracted physically.

This post has been edited by jswong: Dec 22 2009, 02:38 PM

WOW. Great explanation. That's what I been thinking (if the statement is right).

Errrmmmm.... I read your reply 5x and I'm getting a headache....

The only part I understand/agree with is the bolded part. Could you summarize the rest?

Just to reply some of you questions/statement in short:
1) When and where did I state that possibility means inevitability and all science fiction will turn out to be true? Where?
2) The Earth is round because it is proven to be round. Why speculate further as to the possibilities of the shape of Earth when it is already been proven? It is like saying "2+2=4" but maybe it could be 5... or 6.... or -1.....
3) I did not propose any theories. What I'm saying is that researchers have BARELY scratched the surface of the universe and there will be new discoveries and theories. If we only confine ourselves to available theories, then we will not progress. I did mention that current theories might be improved upon or disproved by other future theories.

This post has been edited by kmarc: Dec 22 2009, 07:20 PM

On the twin paradox subject, many forumer suggested that both the twin should aged the same when B touch down on earth as aging is a biological process and both of them should experiencing the similar molecules changes regardless of the velocity and other factor differences. Both should aged 40 years old and not one (A) 40 years and (B) 28 years.

Just like you, it also feel strange when I first tried to understand the special theory (SR) and general theory (GR) of relativity. Both theories defy the common sense we known for years and tells us a different phenomenons on how we perceive things.

The theories indeed suggests that B, the traveler aged slower (hence, younger) than A on earth due to the following:

1) The blue/red shift (like doppler effect) of light on both of the reference frames
2) Time dilation factor - The faster the speed closer to c, the higher the effect
3) Acceleration effect experienced by B in the ship while A was stationary on earth
4) The effect of gravity. Gravity has confirmed slowing down the time. When B is in a ship, the acceleration/deceleration effect on him was like a large impact of gravitational forces acted on him
5) Space/Time compression factor

An experiment was actually been done which was to start off with two identical, synchronised atomic clocks, keep one on the ground and fly the other one around in a plane for a while. When the plane lands, the clock that was in the plane is found to have run a little slower than the one on the ground.

Still not convince enough, ask this question, what do you mean by both A and B should be aged the same, ie the grow rate are the same?

The word rate means that it is time dependent. When traveling near light speed, time is no longer like what we perceive at low speed. The near light speed experience alter the space time continuum. One needs to throw away the idea there is only one "absolute" time idea in order to appreciate this.

If you are interested to know more, here is one of the link:

http://www.gmarts.org/index.php?go=420

Summary
Bob and the rocket have aged only 12 years while Ann and the Earth have aged 20 years.

The twins' times are different when Bob returns because Ann has seen Bob's time running slower than her own on average, while Bob in the rocket has seen Earth time running faster than his own on average.

Cheers.

Twins paradox and time dilations are very real phenomena. The most common example given is GPS. GPS satellites take time dilation into account (and also the slower passage of time in weaker gravity compared to the surface of the Earth). If the satellites do not do this, their time-keeping (and hence distance measurements) will be all wrong. The fact that our GPS units can reliably show us our locations to within a few feet of accuracy proves that time dilation is correct!

I used the word imply. There was no explicit mention of it, hence the word imply. You're implying that future theories will allow such a thing, and this is quite clear, to me at least, reading your posts above. I'm saying that future theories may or may not come out to replace the existing ones does not imply that FTL will ever be possible, whereas you seem to be implying that because we know so little, FTL is possible. It is not known whether it's possible, which is what I'm trying to get at.

I used the Earth is round analogy because you seem to have wanted to show that future theories might change the way we see things, which is true, but I wanted to point out that it could've been any other possibility - it wasn't inevitable that it was going to be a sphere, and putting it into the context of the discussion above, you've neglected the possibility that FTL is impossible in our universe, since you're constantly pushing the 'FTL may be impossible in current theories, but who knows if it's possible in some future theory?' aspect. It may end up to always being impossible.

I'm not saying you should confine yourself to available theories, but what about my fairy/angels theory? I understand that you're inspired by science fiction, and it would indeed be nice to have it come true, it may end up being impossible in the end after all, which is the thing I'm trying to bring into the discussion. Sure, imagine away, but do realise that it may end up impossible in the end, because from what I'm reading of your posts, you seem to only consider/bring up that possibility in future theories without mention that it need not appear in any future theories.

And yes, this wasn't specifically tailored at you alone, which is why you won't recognise some of the things I mentioned above. Rather, this is a general critique about what I've seen in this forum from plenty of participants who love talking about things that are taken for granted in science fiction, e.g. very fast travel between stars, and dreaming up miraculous solutions to problems, and they talk as though it is an inevitability - but they're assuming such a solution exists, when that hasn't even been shown yet.

This post has been edited by bgeh: Dec 23 2009, 11:49 PM

Does this mean that if we travel at the speed of light, we will biologically age much slower? Would we return back the earth (frame of reference) and see our twin as a grandfather while we are still young?

Imagine an ant on a flat surface. As it crawl on the surface, that is the absolute speed of the ant on the flat surface. Time, is like the 3rd dimension to the flat surface. When we say speed of light appear constant to all observer, disregard if the observer is moving or stationary; it's like saying an ant observing a ray of light shining in the 3rd dimension across the flat surface.

Light, in the 3rd dimension, will always appear constant to the ant, be it that the ants are moving or not. However, if the ant is moving at near LS, by normal physic, the speed of light in the 3rd dimension should have change.

When relativity theory say that light will always be constant, the last statement is not possible (where light speed have change). Rather than the light speed is changed, time slowed down.

In our 3 dimensional world, light pass through our 3-D world, slicing through the time-dimension. Which is why light speed will always be constant relative to us, no matter where and how fast we travel.

As we travel faster, still within our 3-D world, we need to obey the "light speed is constant". If not we will catch up with light speed (aka the scenario describe by jswong). The only way for light speed to remain constant, is to slow down the time around the traveler. At least that is how I reason it.

The ultimate question is, does the traveler action automatically slow down as well too? Or his action is still at normal speed but only the time slow down?

If the answer to the first one is true, then he will observe that light is travelling faster than lightspeed. If the answer to the second question is true, then he would probably aged the same as his twins on earth.

no. we dont biologically age slower. we experience everything at normal speed.

assume we travel near lightspeed for 1 year. in our experience (the traveller), only 1 year has passed. but due to the time dilation effect, people on earth probably have experienced 20 years. it's probably like watching the earth on fast forward from outside. and for the earthlings, it's probably like watching the travelers in slow motion.

but like we've discussed before, ur biological clock wont be extended. u will still die by the age of 80-90.

Thx for not getting upset or angry. Some forumers would just become irritated and angry when I "throw" a spanner in their well-oiled machine (aka belief).

"Imply" is such a strong word in this context. I would say "hope" would be a better word (which I did include in brackets early on in the discussion).

For the sake of argument, let's just assume that in this universe, for eternity, FTL is totally and absolutely impossible. That is to say, any object with mass in it's original unaltered state can never travel at FTL speeds. Fine.

However, I'd like to think that in the future, there would be a workaround to this problem. That's why I mentioned something like the warp bubble/field as an example, that doesn't violate any theories but work around it. If we humans are "condemned" to travel at sublight speeds, then we would probably be confined to this region of space for all eternity, however advanced we are (assuming we don't blow ourselves up first!!!). For advancement of the human race, that's a scary thought.

Here's what I'm getting at (Lot's of googling for this). The universe as we know it is estimated to be 93 billion light years across. There are an estimated 100 billion galaxies with each galaxy containing from 10 million to one trillion stars. Our Milky way galaxy (one out of billions of galaxy) is 100,000 light years across and contain 200 billion stars. Our sun is only one star among billions in our galaxy and the nearest star system is Alpha Centauri (wooo! I like the movie "Lost in Space"!!) which is about 4 light years away. The number of stars in this universe would be so much that only a googolplex can encompass it.

Most people would say our human mind probably could NEVER EVER comprehend the scale and numbers involved. That's why it always humbles (and inspires!) me to see this picture from the Hubble space telescope (compressed because it is too large):



The picture was taken from a region of space indicated by the red square below the moon. Each blotch is not a star but a galaxy! You can download the full big picture by googling or here: http://upload.wikimedia.org/wikipedia/en/e...eComparison.jpg

Furthermore, our time in this universe is not even as long as "a blink of the eye" as compared to the estimated age of the universe (estimated to be 13.7 billion years). As such, we are just a tiny tiny tiny tiny miniscule micro insignificant speck in this universe.

This is where I'm coming from. To think that current theories are "correct" and "ultimate" is incorrect, to put it mildly. We have just barely scratched the surface to the secrets of the universe. There are and will be lots of new discoveries to be made, new theories to put forward and new technology to create. With this in mind, some might even dare to say that it is not "IF' we can FTL, it is "WHEN". Again, assuming that we don't blow ourselves up with our own technology in the future.

An approximate analogy to this is that we are a bird. With our bird brain (haha ), we are happily chirping around, flying here and there looking for worms, build a nest and find a partner, die happily seeing our chicks grow up and fly away. In our "bird" world on the tree top, we only understand our own world as we see it while we can't comprehend the world around us. We scold with vigorous chirping when a loud plane passes by. We look on with curiousity at the multitude of cars below and we think humans are aliens coming to grab our eggs. We do not understand words or alphabets or mathematics or science. Yes, we can see and observe all those things around us but just do not comprehend what they mean.

My only regret is that our human lives are short, that we will pass through this period of time as an insignificant being that nobody will notice while the universe goes on without a hint of our passing.

Lastly, you may say that since we are in this age with our limited current theories and technology, we just have to make do with them. Fine by me. As I have stated earlier, I have no quarrels with current theories and what they implicate.

Ok, I'm blabbering . Hope you get what I mean.

Note : Sorry that I'm off-topic. My last blabbering post, honest!!!

This post has been edited by kmarc: Dec 24 2009, 01:07 PM

in reality, the human mind cannot really comprehend numbers that are larger than ~100. so yeah, the billions of stars i nthe billions of galaxies is really incomprehensible to the typical human mind. along with millions and billions of years

when those numbers are thrown around, the general idea is "a lot"

i've always been interested in looking at how the larger picture (the universe) is often reflected in the micro (sub atomic universe).

an atom consists of a nucleus with orbiting electrons, just like planets orbiting a star.

what if... WHAT IF... our solar system is actually just an atom in a larger universe? that a whole galaxy actually makes up one object like a grain of sand, and that other universes combine with ours to make a sandy beach?

and as it infinitely grows outward, so it does inwards. what if each atom in our body is a solar system, and its electrons are potential habitable planets?

the mind boggles... lol.

In Einstein's theory of relativity, once you reach the speed of light. Time for the object will stop.

"In Einstein's theory of relativity, once you reach the speed of light. Time for the object will stop. "

Time stop. But not life. Human still need to regenerate dead cell , etc.... which mean we will age (biologically).

Human consciousness of time flow with time, so is our regenerative capability. if time stop, then it means everything stop. we wont notice if time stop at all, because our brain stop when time stop.

talkin about Einstein u need to understand delusion of speed. I show u in simple way..

u and me wearing a stopwatch. let say we start our stopwatch together. you stay there watching me and i start running at the speed of light in straight direction. to ur eyes (witness eyes) i'm gone. but to my eyes everything around me going faster( like video forwarding). you stay there a few years (dengan setianye) waiting for me to coming back. after 5 years i'm back in front of you. we stop our stopwatch together. and you ask me where did im going in five years. I said im not going anywhere just a few step in front of you and my stopwatch record 5 second only.

as i understand as you approach the speed of light, so much energy is used to travel the distance that less is used to travel through time as time is the 4th dimension through which we travel. It's theoretically impossible for anything other than electromagnetic waves to achieve the speed of light as far as we know. we don't get younger as age is relative. We never do get younger. We just age at a slower age relative to those travelling at a slower speed.

technically, tachyon particles move faster than light.

----

This post has been edited by marsalee: Nov 13 2010, 08:10 PM

This topic is really interesting. I would love to jump in in the discussion but i dare not to. Wrong conceptions might lead to hazardous consequences, as i am not qualified to speak up my mind on this matter. Do continue the discussion, reading this thread is better than watching movies or reading novels I have to say.

there's a safe way to voice ur opinion.

"put it in a form of a question."

lets say u have a bizarre idea which u dont know whether it is absurd or brilliant. put the statement here and then ask a question. let other clarify or justify it.

It's just simple as this.

If you're in a spaceship which travels in a speed of light from point A to point B and the outside of the spaceship calculate the time as 5 years, you will not feel 5 years cause the time stops inside the spaceship. You will feel a split second arrival. When you arrived, people already aged 5 years older than you. Simple as that..

"If you're in a spaceship which travels in a speed of light from point A to point B and the outside of the spaceship calculate the time as 5 years, you will not feel 5 years cause the time stops inside the spaceship. You will feel a split second arrival. When you arrived, people already aged 5 years older than you. Simple as that.. "

Thats the statement that bother me. If Im travel Point A to Pont B in 5 sec. That's means I'm travel fast (my biological will grow/regenerate/deteiorate for 5 sec). When I reach Point B. Point B wont age (from what I see) for 5 Years because he didnt travel(constant speed), he just age normally.

Consider this, If I want to go to Mars using light speed, I might reach there in 7 minutes instead of 1-2 years. That doesnt means ppl in earth already aged 1-2 years. I just travel/reach Mars faster.

However, if I travel/warp space faster that speed of light to Pluto. I will reach Pluto in 10 minutes but human in earth will only see me after (maybe 1 month) because the light that reflect back is slower that the speed i move.

Althought previous buddy already said my theory is wrong and einstein is right. Yet, I still unable to understand what Einstein theory said and his support. but i like jswong explaination.

Other suggest that example show in GPRS and Clock (difference) from earth and space. But those are mechanical, which probably affected by gravity, electromagnet and etc. What we are talking now is more like biological. And Biologically, a cell need to duplicate at certain period of time. and the "time" here means the nutrient that its taken, used, and regenerate.

If we can stay younger means we spend less time in Speed of light to reach a certain distance/area. But that doesnt mean that if we travel around the world in speed of light for let say 1 minute, mean those who are constant speed in earth age 1 day. To me, its only we cover the earth (round the world) faster that earth turn.

But of course, Unless the show in Superman really works. Where's Superman fly in speed of light and turn the earth the opposite way (means he went back to the past)...zzz

What do you guys think?

This post has been edited by 100n: Dec 29 2009, 10:28 AM

distance between stars is calculated in light years which is the amount of time light travels between two stars. so eg if the distance between our sun and another star is one light year it will take one year using speed of light for us to reach to the other star. (do correct me if I'm wrong)

really love science fiction: the time machine (about time travel) and the most recent one, pandorum (space travel w/o light speed)

should read The Forever War too. I haven't read that myself, but it is about a war between two star systems. and the soldiers have to use faster than light travel. so centuries pass as they travel between the stars.

I have a question.

why does our biological clock moves slower while moving within/faster than speed of light?

all i can comprehend is that we just move faster with the same speed that light travels.

and.. if our biological clock moves slower than while traveling at the speed of light, does that mean if we manage to stop light from traveling so fast, we might see another form of light?

If u are going to mars with the speed of light and u reach there in 7 minutes, u won't feel as if u travelled 7 minutes. U feel just a split second. While others who is not on that ship of yours will feel 7 minutes already passed away.

About Superman, that's a fictional character, please don't compare..

If you are moving the same speed with light. Time inside the ship including you will stop.
Even if the ship travels for 1 million years, you'll feel split second.

If 1 million years of travel = feel a split second. Does my body age a split second? Or will my body just die.

Everything stops. Your time, your body your mind. EVERYTHING.

You can read more on Einstein's theory of relativity.

We can conclude that time travelling is possible if we(humans) are able to travel in the speed of light.
BUT, what about going back to the past? Is that possible? Explain.

If an object can move FASTER than the speed of light, it can go to the past. But I'm pretty not sure about this fact. I have to research it more..

i think it only make sense if you go into the future with that speed of light theory... past is impossible

something that has happened, cannot be unhappened

This post has been edited by Alone: Dec 30 2009, 01:32 AM

ok here is relativity take their part. in our space n time we can go to UK and back to KL and vice verse easily using flight . but we cannot reverse our time. i mean we CANNOT going back to yesterday.but when we moving at speed of light, space n time changing their place. u can reverse or forward ur time easily but once u flown to UK, u well never going back to KL.

Yes, what you guys are saying may be true. But according to Michio Kaku, there are THEORIES about time travelling to the past(Check out on YouTube).Therefore, I personally think that time travelling to the past is possible, it is only a problem of engineering,...
Check out this article that i've found:


"If we could journey back into the past, history would be impossible to write. As soon as a historian recorded the history of the past, someone could go back into the past and rewrite it. Not only would time machines put historians out of business, but they would enable us to alter the course of time at will. If, for example, we were to go back to the era of the dinosaurs and accidentally step on a mammal that happened to be our ancestor, perhaps we would accidentally wipe out the entire human race. History would become an unending, madcap Monty Python episode, as tourists from the future trampled over historic events while trying to get the best camera angle.

But perhaps the thorniest problems are the logical paradoxes raised by time travel. For example, what happens if we kill our parents before we are born? This is a logical impossibility. It is sometimes called the 'grandfather paradox'.

There are three ways to resolve these paradoxes. First, perhaps you simply repeat past history when you go back in time, therefore fulfilling the past. In this case, you have no free will. You are forced to complete the past as it was written. Thus, if you go back into the past to give the secret of time travel to your younger self, then it was meant to happen that way. The secret of time travel came from the future. It was destiny. (But this does not tell us where the original idea came from.)

Second, you have free will, so you can change the past, but within limits. Your free will is not allowed to create a time paradox. Whenever you try to kill your parents before you are born, a mysterious force prevents you from pulling the trigger. This position has been advocated by the Russian physicist Igor Novikov. He argues that there is a law preventing us from walking on the ceiling, although we might want to. Hence, there might be a law preventing us from killing our parents before we are born.

Third, the universe splits into two. On one timeline the people whom you killed look just like your parents, but they are different, because you are now in a parallel universe. This latter possibility seems to be the one consistent with the quantum theory.

The film Back to the Future explored the third possibility. Doc Emmett Brown (Christopher Lloyd) invents a plutonium-fired DeLorean car, which is actually a time-machine for travelling to the past. Marty McFly (Michael J. Fox) enters the machine and goes back and meets his teenage mother, who then falls in love with him. This poses a sticky problem. If Marty's teenage mother spurns his future father, then they never would have married, and he would never have been born.

The problem is clarified a bit by Doc Brown. He goes to the blackboard and draws a horizontal line, representing the timeline of our universe. Then he draws a second line, which branches off the first line, representing a parallel universe that opens up when you change the past. Thus, whenever we go back into the river of time, the river forks into two, and one timeline becomes two timelines, or what is called the 'many worlds' approach.

This means that all time-travel paradoxes can be solved. If you have killed your parents before you were born, it simply means you have killed some people who are genetically identical to your parents, with the same memories and personalities, but they are not your true parents."

Extracted from 'Physics of the Impossible' by Michio Kaku (Allen Lane); available from Telegraph Books for £18 plus £1.25 p&p. Call 0870 428 4115 or order online at books.telegraph.co.uk
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The 'past' that u 'go back' to might not be ur actual past. Its just another constructed universe at which the time is the same as ur past but at a different space/universe. While the space/universe that u left goes on without u.

U then, needs to go back to the time and space/universe from where u left to pick up where u have left before u go back to the 'past'.

The two variables that needs to be locked then, is the time and space, in ur 'time machine' GUI.

Exactly, that is an another theory, which means different time can lead to different dimension.

For example if you go to the past and kill your parents before you were even borned, you will not gone, instead you'll be in a new dimension which is parallel to the previous one..

Even research more or not, doesn't matter nor can come out any conclusion.

It is just a hypothesis, it is not something proven nor human kind have any understanding of it. It is a theory aka hypothesis.

Of course it is....There is no harm doing it either.

Its interesting to me how we can create another plane of thinking to repair the illogical paradox of the 'grandfather paradox'. It exercise ur mind to really think our of the box and interwine the logics with the illogicals.

In reality, it's not just a split second had passed. You will realize the passage of time, but only if it's an alcubierre type warp drive in which you're moving at lower than 'c' in a warp bubble while your effective velocity is 'c' or higher than 'c'. If it's not a warp drive, you can only move at relativistic speeds at most, but that depends on how much energy you can expend on propulsion to offset the increase in apparent mass.

Things don't stop. Things go on, only the flow of information "stops" (for information that travel at the speed of light or lower) because it can't reach its destination. If you're moving at the speed of light, or even relativistic speeds, the electrical signals in your body will have a harder time getting from point A to point B because of (1) relativistic mass increase of the charge carriers and (2) time dilation experienced by the signal propagation.

Things don't just stop dead mysteriously. It's all about information not being able to be transmitted faster than the speed of light, and objects with mass not being able to approach the speed of light. Even entangled photons can't be used to transmit information faster than light, but it could be due to some "hidden variable" e.g. information HAS moved faster than light but we're not able to detect it without breaking the entanglement and scrambling the information.

Ah... never thought of that.

You mean, Speed of light is faster than nueron signal speed to transmit information for our brain to decode?

internally everythign is normal. its the interaction between internal and external thats messed up.

Not quite true. Physicists leave this possibility open.

You have a point on thing happened cannot be unhappened. This is called cause and effect casual loop. Changing the past is paradoxical, however affecting the past is logically feasible.

Kurt Godel (who is more famous for his Godel's incompleteness theorems), a colleague of Einstein, came out with the following comments after going through a lot of research on Einstein gravitation field equation:

"By making a round trip on a rocket ship in a sufficiently wide course, it is possible to travel into any region of the past, present and future".

Why so? The reason is past, "Now" and future are merely an illusion. There is no absolute "Now" per say. Just look at the twin, for Ann who is station on earth, her time that she "feel NOW" is 2010. For twin Betty who is traveling near light speed, her time that she "feel" could be 2005 and shed aged 5 years less that Ann.

For a population of living organism on Halley Comet which travel in high speed, the time "Now" that they feel could be 300BC (earth time) and they might be observing the event happening in 300BC now.

The reality is, there is no such thing as "Now". It is just a misinterpretation on our part on tracking the events around us in this spacetime continuum.

The following is a snapshot from the discussion under a different topic "time - discussion".

If you do not believe, try this. Say "Now". By the time you say "Now", you assume that the "Now" you just said is gone and you have to repeat saying "Now". Again, it is gone, and you have to keep repeating saying "Now" again.

You assume that every "Now" you mentioned has "flown" through time and become the "Past". And you assume that every moment is "Now". If every moment is now, what do you mean by tomorrow? You have to agree that tomorrow will never come.

If you are interested, you could go to the time topic for more explanation and discussion.

Have a wonderful new year ahead!

well here's a concept of mine, if one could move really fast as the speed of light or as the neurons in our body imagine this, if speed present now is normal e..g a boy drops a pen from his hand but at the same time u went to another planet, stop by there, proceed to a nother galaxy sit and talk with those people in that particular planet in that particular galaxy * assuming the living things/creatres there moves as fast as u do* and come back to earth near the boy. when u c him it looks as if nothing changes. This may look as though stopping time but its we are actually moving very fast but for the boy..its just normal.

Put yourself in a tortoise position.