ThoseDeafMutes
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Jarmel said:
Read the thread.
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Why nothing can travel faster than light: An easy-to-understand explanation
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Read the thread.
AceBandage
Banned
Jarmel said:
Steroids and cheetah blood.
#winning
Here's a fun little video some of you might enjoy:
http://www.tenthdimension.com/medialinks.php
It's an attempt to explain a possible manner in which ten dimensions may exist in layman's terms.
http://www.tenthdimension.com/medialinks.php
It's an attempt to explain a possible manner in which ten dimensions may exist in layman's terms.
ThoseDeafMutes
Member
StuBurns said:
Found on 4chan:
Okay, given our current understanding of physics there is no way to directly answer the question "why nothing travels faster than light". It's like a basic axiom you have to assume is true for everything else to work as it does, like 1 + 1 = 2. In order to find a real answer to this question, we would have to make another discovery about the fundamental nature of the universe. And even then you can still ask "why why why why". Well that's what physicists are doing.
Part of this mentality stems from the fact that light travels at approximately 300,000 km/s, because this number seems kind of arbitrary, right? That's a faulty mindset. Kilometers are a human invention, there is no such thing as a kilometer or any objective measurement of distance (I don't want to get into planck lengths or whatnot cause I have no idea what they are). It's just a convenient way of reducing the concept of distance into tangible segments. It's the limitations of human thought that makes these universal constants seem arbitrary, not the constants themselves.
Part of this mentality stems from the fact that light travels at approximately 300,000 km/s, because this number seems kind of arbitrary, right? That's a faulty mindset. Kilometers are a human invention, there is no such thing as a kilometer or any objective measurement of distance (I don't want to get into planck lengths or whatnot cause I have no idea what they are). It's just a convenient way of reducing the concept of distance into tangible segments. It's the limitations of human thought that makes these universal constants seem arbitrary, not the constants themselves.
Nope. His point was that a particle's velocity vector can have many directions but only one magnitude (the speed of light). Whether any of the components are negative is irrelevant because the magnitude is computed as the square root of the sum of squares, per Pythagoras. In fact, his explanation makes no effort to explain why you can't go backwards in time, only why you can't go faster than light.Torquill said:
Flachmatuch
Member
OliveJuice said:
But your explanation is not nearly as deep and doesn't explain the issue at all - it just rephrases it.
I also disagree with this. Newton's first law is pretty awesome and actually a lot of people find it completely unintuitive. I don't think "laymen" do in general understand it very well.
Agreed. I remember reading somewhere about a quiz with an illustration of a man running who drops a ball. The three choices were the ball going behind the man, the ball moving with the man, and the ball moving in front of the man. I think they all received an equal amount of votes, indicating something seriously wrong with our education system.Flachmatuch said:
ColonialRaptor
Member
Just to ad a bit of fuel to the fire here but I've always thought this and wondered why scientists have never seemed to mention this idea when they talk about light, speed of light, super density and super energy requirements for going faster than the speed of light, maybe I'm just over imaginative and uneducated but...
Whatever a black hole is... Whatever is happening there, something there has to be moving faster than the speed of light because it is so heavy that it sucks light in... You see what I'm saying? Light is the fastest thing right? If it's the fastest thing then it should be able to outrun anything yeah? But if a black hole absorbs light... Then whatever is in that hole is sucking light in faster than the speed of light, right?
Whatever a black hole is... Whatever is happening there, something there has to be moving faster than the speed of light because it is so heavy that it sucks light in... You see what I'm saying? Light is the fastest thing right? If it's the fastest thing then it should be able to outrun anything yeah? But if a black hole absorbs light... Then whatever is in that hole is sucking light in faster than the speed of light, right?
Not exactly. Think of gravity not as a tangible thing but a way of describing how space is shaped. Light moves through space. Therefore, any curvature extreme enough will prevent light from escaping. As far as I know, light DOES move at the speed of light inside a black hole, it's just always angled toward the center rather than away because of the severity of the spacial curvature.
I have a question. Suppose in this hypothetical scenario, you have a sort of pendulum.
On the end of this pendulum is a ball. But halfway in between the point of origin and the end is another ball.
Suppose you could swing the pendulum so fast that the interior ball was moving at the speed of light. Would this not mean that the ball at the end of the pendulum would be moving faster than the speed of light. What is the explanation for how this is possible?
On the end of this pendulum is a ball. But halfway in between the point of origin and the end is another ball.
Suppose you could swing the pendulum so fast that the interior ball was moving at the speed of light. Would this not mean that the ball at the end of the pendulum would be moving faster than the speed of light. What is the explanation for how this is possible?
Your entire explanation is kind of missing the point as your spatial velocity in your frame of reference is always zero - you can't move away from yourself. Your relative velocity to other objects is meaningless - in your own world you're always motionless.ThoseDeafMutes said:
DeathIsTheEnd
Member
It isn't.Divvy said:
That's quite simple. Mass particle could never reach speed of light since it'd have infinite momentum. Assuming that the inner object moves with the speed close to speed of light, the outer still wouldn't hit or exceed speed of light since velocities do not add up linearly.Divvy said:
ColonialRaptor
Member
Jeez... Thanks for the black hole explanation stuff guys. Perhaps a black hole is different as well, perhaps it just slows down the light and time so as to not allow it to escape... That's how I understand it as well, but isn't that a factor of something with mass going the speed of light? Perhaps black holes are created by the phenomenon of mass reaching or passing the speed of light...
It still baffles me and gravity still doesn't make a whole lot of sense to me as it is while we think about the spin of the earth and it's rotation around the sun... What about the movement of our solar system in this galaxy, and this galaxy in the universe, I mean - for all we know, before we add any speed through man made forces we could already be moving at 1/2 speed of light away from the centre of the universe and not even know it... Because everything around us is moving in conjunction with us... You know what I mean?
I don't know exact details about this but what about the part of the atoms that teleport from one side of the atom to the other visibly during observation?
Also, if light has no mass and this is what allows it to travel at the speed of light because it is light so it is not affected by gravity so it essentially "glides free" what then allows light to carry energy? And in this case, there is light all around us all the time every where (almost), shouldn't this be the best and cleanest energy source available?
It still baffles me and gravity still doesn't make a whole lot of sense to me as it is while we think about the spin of the earth and it's rotation around the sun... What about the movement of our solar system in this galaxy, and this galaxy in the universe, I mean - for all we know, before we add any speed through man made forces we could already be moving at 1/2 speed of light away from the centre of the universe and not even know it... Because everything around us is moving in conjunction with us... You know what I mean?
I don't know exact details about this but what about the part of the atoms that teleport from one side of the atom to the other visibly during observation?
Also, if light has no mass and this is what allows it to travel at the speed of light because it is light so it is not affected by gravity so it essentially "glides free" what then allows light to carry energy? And in this case, there is light all around us all the time every where (almost), shouldn't this be the best and cleanest energy source available?
Look up Schwarzshild radius, it'll give you some basic insight into black holes. It's nothing like you suggest. Basically black holes have sufficient mass density that they create field strong enough not to allow any object escape it unless it has infinite momentum.ColonialRaptor said:
Your velocity wrt other objects is meaningless.
Do you mean quantum tunelling? It has finite velocity and while some experiments seemed to show its FTL, these results are easily explained by the uncertainty principle - basically the time can't be measured accurately enough to determine the speed of the tunneling.
Light is affected by gravity and light carries energy without mass. You can't really obtain the energy from the lowest vacuum level even if in theory it has infinite energy, so your suggestion isn't really feasible. We have problems with economical conversion of the Sun radiation into energy, if we could achieve just that our energy problems would be solved.
To grossly simplify things:
Some of you might feel better knowing that most scientists don't know how gravity really works either. It upsets many of their pretty equations they use to figure out the universe and the holy grail of physics right now is to create a mathematical model of everything that somehow includes gravity with all the other forces in the universe (that they have a better understanding of).
Some of you might feel better knowing that most scientists don't know how gravity really works either. It upsets many of their pretty equations they use to figure out the universe and the holy grail of physics right now is to create a mathematical model of everything that somehow includes gravity with all the other forces in the universe (that they have a better understanding of).
Black-Wind
Member
Wait, is there no such thing as wormholes?
Because I always understood it as "the fastest way to get from point A to point B would be a wormhole".
Because I always understood it as "the fastest way to get from point A to point B would be a wormhole".
weekend_warrior
Banned
Black-Wind said:
Wormholes are, at best, a very very far fetched hypothetical idea. And even so, traveling through a wormhole still wouldn't require you to exceed the speed of light since they bend space in such a way as to bring to very far distances much closer.
Black-Wind said:
Isn't that based off what Einstein said about how the universe bends? I still believe that while traveling faster than light is impossible there is some way to travel in some manner that would beat light. Bending space. Tachyon drive. Something. People will find a way.
The Shadow
Member
Black-Wind said:
Ever watch "Event Horizon"? The way they describe wormholes explains how you could get from point A to point B that seemingly looks like you're going faster than light but really, you're not.
A piece of paper is the universe. Draw a dot at one end. That's you. Draw another dot at the other end, that's your destination. Draw a line between them. That's the distance between you and your destination. You can not go the speed of light or exceed it.
Now, fold the paper so that the destination dot and the you dot touch. That's a wormhole. You didn't do any traveling so you never exceeded c.
All this dimension, space/time travel, space warping stuff is fascinating to me, but by reading some posts, i notice that some people get confused when talking about time.
I dont know how to put it, but i always have related "a dimension" to a "spatial freedom"
Can anybody correct me if i am wrong here?
but let's say that hypothetically:
a 1D being could only move forward/backward
a 2D being could move forward/backward/up/down
a 3D being could move any of our directions
any dimension beyond that, is out of our comprehension... right?
now when we talk about time as a dimension, we now are refering to the conventional dimensions (the ones i explained before) as a group of dimensions, thus making us 2D beings with the axes being space/time
and thats why time isn't considered a conventional dimension since it would still apply to the 1D and 2D conventioanl dimensions.
Right?
I dont know how to put it, but i always have related "a dimension" to a "spatial freedom"
Can anybody correct me if i am wrong here?
but let's say that hypothetically:
a 1D being could only move forward/backward
a 2D being could move forward/backward/up/down
a 3D being could move any of our directions
any dimension beyond that, is out of our comprehension... right?
now when we talk about time as a dimension, we now are refering to the conventional dimensions (the ones i explained before) as a group of dimensions, thus making us 2D beings with the axes being space/time
and thats why time isn't considered a conventional dimension since it would still apply to the 1D and 2D conventioanl dimensions.
Right?
Sure you can. For a sufficiently large black hole, you wouldn't even notice as you cross the event horizon. You'd have passed the point of no return, but it's not much different than the point in space right outside it.StuBurns said:
Of course, to an outside observer, you'd move increasingly slowly the closer you got to the event horizon. They'd never quite see you reach it, but as you approached it they'd watch you disintegrate.
That's from their perspective, though. From your perspective, none of that happens and you can live out an entire, perfectly normal life inside the event horizon of the black hole. You could even have entire generations of people living and dying entirely within the black hole before they're pulled too close to the center and are destroyed.
I still don't think so, I tried to do some research about it yesterday and it seemed to point to me being right, that the light shift would be pretty much complete and there'd be no visible light. There doesn't seem to be anything clearly saying either way though.Slavik81 said:
Black-Wind
Member
StuBurns said:
weekend_warrior said:
Well damn. :/
Darklord said:
Thats exactly how it was explained to me in some vid I saw (Maybe that was it?)The Shadow said:
So yeah, I was referring to shortest amount of time it takes, not "speed". Thats how I figure a wormhole works ... the ends can be 100s of light years away but once you go through one end you instantly come out the other.
When it comes to explaining abstract physics, analogies like dots on a paper or balls on a rubber sheet are at best handy fictions that are not really representative of the underlying mechanics of the universe. You should always take those things with a tub of salt.
Four, five, six or more spatial dimenions are well within our comprehension. They just look really, really weird, and they're not easy to explain.Mr. Robot said:
To answer your question, I'd like to bring up what's commonly called "the arrow of time." Everything that exists in the three dimensions we know and love is constantly advancing along a fourth axis, which is not a spatial one. (Picture it as a little number that that increases.) The speed at which we make progress in the "time" direction depends on how fast we're moving in the other three, just like how any vector in 3-space is the sum of its components.
The Shadow
Member
StuBurns said:
Nope. Everything I've read or watched on the subject suggests that you'd still be able to see outside. That's assuming you'd avoid the high radiation and spegettification.
Halycon said:
Your point being?
OK, I'm trying to understand why we need infinite energy to go as fast as light for things with mass.
E=ymc^2
y=(1-(v^2/C^2))^-1/2
If we were going at the speed of light, then y=0. 0 x mc^2 is 0, so E=0. In this case, zero represents infinite energy, or all the energy in the universe. Is this right?
E=ymc^2
y=(1-(v^2/C^2))^-1/2
If we were going at the speed of light, then y=0. 0 x mc^2 is 0, so E=0. In this case, zero represents infinite energy, or all the energy in the universe. Is this right?
ColonialRaptor
Member
Ohhhhh!! Dude!!Orayn said:
Finally I get what the text in the OP was trying to describe.
My lord. I am now in the camp with everyone else saying that it was a crap explanation.
So, going the speed of light is like having no time at all? Or in a sense, stopping time. Oooer! Thats... Whack.
I definitely get it now... And it's brought a whole bunch of new thoughts into my head but the absurdity of it is, I want to know why the universe chose that particular speed as it's hard limit. I suppose the speed of light / time is the best starting point for working out the fundamental mathematic calculations of the universe because it's a constant.
It makes sense to say light is time right?
I wonder what it would be like to be a particle of light.
ColonialRaptor
Member
Because light is energy and has no weight.SoulPlaya said:
It baffles me though as to think of what it's like for that light, is it just flickering for an instant? What is time like at the speed of light if time has stopped at the speed of light... Ugggg!!
Ok I'm gonna break the time theory some more. Again the way time is used in these examples posted is so broken it's hilarious that they do all this science and math but forget that time is something made up by humans. So something traveling faster than light could "time travel" into the future if it travelled fast enough right? The speed is measured by a clock. A clock that is based on seconds, sunrise sunset and all that jazz.
Let's say you could travel 100x the speed of light and into the "future". Even if everything else is moving normal speed earth is still here. You could fly around the planet 100 times in 1 hour and it wouldn't mean anything. You didn't travel through time you just moved really fast. You'd land and it'd still be today. Easier way to picture this is to scale it down. Take a Corvette vs a model t on a drag strip. Launch and of course the Corvette gets to the finish line first but did it time travel? No.
Something like teleportation sounds like a more proper term to use. There is no "future" to travel to because everything else remains. Now travelling to a different dimension altogether somehow or an alternate time line or earth would make more sense if you're looking to time travel and end up in 2025 or something.
Let's say you could travel 100x the speed of light and into the "future". Even if everything else is moving normal speed earth is still here. You could fly around the planet 100 times in 1 hour and it wouldn't mean anything. You didn't travel through time you just moved really fast. You'd land and it'd still be today. Easier way to picture this is to scale it down. Take a Corvette vs a model t on a drag strip. Launch and of course the Corvette gets to the finish line first but did it time travel? No.
Something like teleportation sounds like a more proper term to use. There is no "future" to travel to because everything else remains. Now travelling to a different dimension altogether somehow or an alternate time line or earth would make more sense if you're looking to time travel and end up in 2025 or something.
ThoseDeafMutes
Member
It's about as made up as space. Time is the dimension asymmetrical with regard to entropy. If time "didn't exist" nothing could progress, past or future, no changes could occur and nothing would ever happen. Just like things take place at positions in space, they take place at positions in time. Spacetime is warped by the presence of energy, and your velocity influences the rate at which you experience time. If time did not exist and was just "made up", none of this would make sense. Seconds, minutes, hours, days, weeks, months, and years are all arbitrarily defined units, but the thing they measure, time, is not.
I have no clue what you are babbling about.
Yeah but you still can't go forward in it. Time in measurements ok, the past being a moment in time yes. The future hasn't happened until we get there so you can't time travel. Sure it may be possible to beat the clock but that's all you're doing. Another example is other planets. Some planet somewhere is spinning faster than earth, some galaxy somewhere has faster day night cycles. If we could see it would we say they're time travelling? No. They'd just be moving faster.
No. Say you could watch something move that quick if it existed. You'd be standing at normal time and they'd be orbiting earth. Sure you could watch them zip by over and over but no one's time travelling. They just travelled faster than you. They aren't going to end up in the future somewhere. And time is going to pass by based on a clock still. 5 minutes passed by for you and even tho they flew around the planet 50 times "breaking" time, when they land it's still only 5 minutes that passed.NotTarts said:
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