Theoretical Physics!

Animal

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Ok, i'm a biology man myself so my knowledge of physics is not that extensive but:

We all know the phenomenon of time dialation (How time perceptions are altered by travelling) and this is related to travelling along the space-time continuum bla bla.

Ok now, in theory when we travel at the speed of light, for the traveller the journey will be instant because they will be travelling along with time along the continuum, for anyone else time will pass normally. Now, this theory assumes that light and time have the same speed. Therefore time must have a tangible existance. If this is true then are there not particles which make up time? Can time be disrupted?

Also if you travelled faster then the speed of light ( Physically impossible, but...) then would you not arrive at your location before you actually realised it, then also how could you possibly be there because time governs existance.

Terefore the space which you would occupy would not react in 'time' to your presence and then you would cease to exist but become something of a merge between these two existances (the two points in space-time)

I know some people on this forum know there shit, someone here has a degree in physics apparantly so...

Theorys? Hypotheses? Flames?:cheese:

Anything would be nice...
 
Hey go have a beer, HL2 will be out soon.

Don't give yourself a nosebleed, it's all relative.:cheers:
 
<el Chi hears the words "physics" and "theoretical" and implodes. But in a I-comprehend-thephysics-behind-this-happening kind of a way>
 
Originally posted by Lordblackadder
Hey go have a beer, HL2 will be out soon.

Don't give yourself a nosebleed, it's all relative.:cheers:

Lol the best advice i've heard all day.

I hope when HL2 comes out these forums won't become flooded with noobs:x
 
Actually Light Speed is a kind of barrier that you can't pass, so travelling faster than the speed of light isn't impossible, you just can't get there.

There are some theoretical particles that are called Tacyons. These are just particles travelling faster than the speed of light. There's a kind of symmetry in Relativity, so a particle travelling at the speed of light would:

* Go backwards in time.
* Speed up as it loses energy (instead of slowing down)

And just be an opposite to usual particles.

But nobody has detected Tacyon's yet and it's been a while since I read up on them so I'm probably just typing absolute rubbish.
 
Ok Animal, I think I understood you REAL question.


No, you can't make a time machine to have HL2 early. Sorry.
 
Did you see the problems associated with faster then light travel i posted?

Ok Animal, I think I understood you REAL question. [No, you can't make a time machine to have HL2 early. Sorry.

NOOOOOOOOOOOOOO;(
 
Time isn't changed as a 'perception' but rather...

Time and space are relative to one another. If you have a simple graph, speed on one axis space on the other, you can plot yourself in one spot & plot someone else (who is in a spaceship traveling very fast around an orbit above your head) in another spot. That person who is traveling faster than you will be younger than you when they come back down - how much younger depends upon how fast they traveled - if they were going close to the speed of light they wouldn't have aged much at all RELATIVE to your age.

This theory (part of Einstein's relativity stuff) was proven a long time ago, by simply building two atomic clocks; they put one on the ground in a building, put the other in a jet and flew it around the earth a few times - as fast as the jet could go, in other words, because what we are interested in here is the clock's SPEED relative to the 'stationary' clock. The clock in the jet, when brought back down, was younger than the clock on the ground.

And by the way, the travel isn't perceived as instantaneous by the traveler; if he travels ten light years at the speed of light, it will take him TEN years! When he returns from HIS ten-year flight, you will have been dead & buried many years ago in your time. His SPEED has put him on a different plane of existance, in a sense. All of us come down off of an airplane imperceivably younger (compared to/relative to other people) than if we had stayed on the ground, because we traveled really fast for a while. We still had to spend OUR time making the journey.

This is really as simple an explanation as can be made, but serves very well.

So the upshot of all this is, that one way of living a longer life is by somehow building a spacecraft that does two very important things: Slows your metabolism to a crawl - suspended animation - while you travel for many years; goes close to the speed of light without smashing in to something too big. So with this craft, you could leave earth, go to sleep for 100 years, go REALLY REALLY FAST for most of those 100 years. When you returned to earth, you won't have aged much b/c your metabolism hasn't had a chance to physically age your cells, and your SPEED has protected you from the passage of time RELATIVE to everyone else on earth - in other words you show up a young man many hundreds of years in earth's future - a la Buck Rogers.

Yes I'm a science/astronomy :dork:
 
Originally posted by Animal
Ok now, in theory when we travel at the speed of light, for the traveller the journey will be instant because they will be travelling along with time along the continuum, for anyone else time will pass normally. Now, this theory assumes that light and time have the same speed. Therefore time must have a tangible existance. If this is true then are there not particles which make up time? Can time be disrupted?

Also if you travelled faster then the speed of light ( Physically impossible, but...) then would you not arrive at your location before you actually realised it, then also how could you possibly be there because time governs existance.

No. See my post above ^^^:cheers: :cheese:
 
The gist of this theory is that time is actually a quantum wave, if you travelled somewhere at the speed of light you would not be able to perceive the journey because you would be travelling parallel with time rather then letting it pass by.

Read up on it.

I agree with cryogenic suspension though, it's gonna be the only way of making slower then light journeys to anywhere meaningful.

The speed of light isn't really that fast, i think it's estimated to be about:

six hundred and sixty nine million, six hundred thousand, Miles Per Hour.

669,600,000 MPH:eek:

Not even a billion, pathetic:cheese:

edit: Thx 4 the post!
 
O, I see this is a post-Einsteinian theory of travel past the speed of light. Well there's lots of theories about lots of different stuff out there; beating Einstein's speed limit is a pretty tough one to me. I'll wait to 'read up' about it when I see a significant portion of the scientific community accepting it; I'd never get anything else done if I read every theory out there, especially from the guys that are trying to make a name by refuting one of Einstein's basic principles.

I'm more interested in the subatomic quantum stuff - those bits of matter that Einstein refused to believe in but to the research community at large obviously exist. Particles that seem to appear literally out of thin air, that seem to go back in time or forward into the future, that seem to communicate with each other over vast distances, that's cool stuff. (Now if your theorist is using this type of quantum data to suppose that a person - and not just a single subatomic particle - could conceivably travel faster than the speed of light, I'll be very uninterested in reading up on it.)

Nice debate tho, thanks.
 
The whole thing with the speed of light presents an interesting situation. It's kind of like that "if a tree falls in the forest but noone is there to hear it" saying. This means we really have no clue about whats happening outside our solar system. What we see happened a long time ago. Even if the sun suddenly disappeared for 4 minutes we wouldn't notice a thing.

Also recently I read something in the NYT that the 4 current dimensions are decaying and at some point "a bubble of 10-dimensional space will sweep out at the speed of light, rearranging physics and the prospects of atoms and planets, not to mention biological creatures. " Not good news, IMO.
 
Haha, I've seen no evidence to see time or physical dimensions decaying, if you are in fact referring to time as the fourth dimension... and not visual dimensions, as in if you have no eyes you can not see (can be considered 1 d) if you have one eye you can see in 2d, if you have two eyes spaced apart you can see in 3d, if you say had a 3rd eye off in front of your head to the right, and were to look at a object placed between all 3 eyes you could actually see it from 3 angles at once or (4d)...

Aside from that though another interesting tid-bit i saw on Tech TV was about the whole quantum worm-holes hypothesis, that technically if we could thread negative enrgy through one to keep it open (excluding that it could open into space and would suck all the air out or into a sun and toast us all) while in possession of both "ends" we could put one of those on a plane going at near light speeds and since less time has passed for that in essence go back in time although not to a point before when you started to make it. Just a neat thought.
 
Why don't we just wait until HL2 comes out and program a machine that goes the speed of light and see what happens?
 
solid i always wanted to be a pilot u just gave me more of a reason :) btw i understand everything you talking about(u put it so simply) and i wish i knew all that, comming off hte top of your head is pretty amazing. i always felt i was born in the wrong time. i want to live far into the future and i dont think im going to be the first one to achieve immortality. life can be so depressing sometimes.:dozey:
 
what if you could invent something that made your molecules move at the speed of light so you never grew a day older?
 
I'm just curious, I thought anything with a mass could not travel at the speed of light? I thought I read that somewhere. If it's true it means human beings could not actually travel at or above the speed of light.
 
Originally posted by qckbeam
I'm just curious, I thought anything with a mass could not travel at the speed of light? I thought I read that somewhere. If it's true it means human beings could not actually travel at or above the speed of light.

That's the part of the theory that gets tricky to explain in layman's terms. Yes, as an entity with mass travels faster, it gains more mass; at near-speed of light, it approaches infinite mass. This is a big no-no as far as the rest of the universe is concerned. I'd have to read up on it again to remember all this part of the theory.

What's cool to think about though is that a photon that is created will not age at all, it can only be converted into a different type of energy (heat for example). That is why, when astronomers are looking at light that has traveled for billions of years, they are really looking back into the past that many years - the photons haven't aged at all, the image they are showing is exactly what it looked like that many billions of years ago. Of course a single photon tells us nothing, but many millions of them all together - from a distant sun or galaxy, for example - give us a clear look at an entity that is long-dead (most likely). The photons don't age because they are traveling the speed of light! Unless they get slowed down by something, temporarily (glass of water e.g.).

So this is one of the big technical problems with what I was discussing earlier - how to go really super-fast enough to bring us into the 'future' of the rest of the world that has traveled much slower than us, without ramming into another massed entity and destroying everything around like an enormous chinese fireworks factory explosion. I'll have to go to the library and freshen up on my theoretical physics! (Keep in mind I am an amateur at this, I just like thinking about it all, I haven't had any formal training.)
 
Originally posted by KiNG
solid i always wanted to be a pilot u just gave me more of a reason btw i understand everything you talking about(u put it so simply) and i wish i knew all that, comming off hte top of your head is pretty amazing.
Hey just a quick note to say "thanks" for such a compliment! (Compliments are so rare on public forums that I just had to acknowledge it, gratefully I might add.) :cheers: Sometimes I explain what's on my mind better than other times - just ask my wife!:cheese:
 
You do realise that photons don't actually exist in the sense of particles, they are just representations of electromagnetic energy, it's known as wave/particle duality.

Therefore they can't age anyway, they maintain their energy state as long as they are present in the vacuum of space. Also the reason why they travel at the speed of light is because they have no mass, only momentum. They can have momentum even though they have no mass because mass and energy are basically the same thing. This has been proved.

The theory of massed bodies travelling at the speed of light is based on transforming our complete mass into momentum energy, which is not as hard as it seems according to some scientists.
 
The funny thing about theories, is that we don't really know if they are right. But they seem to fit so for the time being it will do.

I would contribute, but i really cant be bothered right now. Ive been doing lots of brain taxing stuff all day and now i just want to kill things.
 
When a photon passes through glass it will not slow down. It will be absorbed by an atom and then released again some time later. Then it will collide with another atom and this will be repeated until the photon leaves the medium in question on the other side (depends on the medium ofcourse). Because of the time it takes for the absorbation and release it will appear as light slowed down and it did but the photons didn't. :)

When the photon travels between the atoms it's speed is ofcourse C.
 
Time is not constant

When discussing relativity, one thing that is pretty confusing is that time is not constant. The only constant is the speed of light (in a vacuum). Time is a human invention in a sense, and it is perceived relatively by entities traveling at different speeds.

Also according to the theory, information cannot travel faster than the speed of light. However there are things that may travel faster than the speed of light, but they cannot contain information. This is kind of a silly example, but here goes: If an infinitely large pair of scissors is closed at the speed of light, the cutting point between the two blades can travel faster than the speed of light. Clearly this conveys no information, because unlike a wave there is no phase or other information carrying property.

The current challenges in building faster and faster silicon-based circuits is due to the fact that the speed of light is constant. As circuits become "longer," the time it takes for electrons to travel through them increases. So, there will be a limit to how much the clock rate of these circuits can be increased. This is actually a real problem in the industry today.

Okay, I'll stop now! :dork:
 
The problem with circuits is that they are becoming so small that they are only able to allow a few electrons through at a time, this means that the resistance is massive so the heat and the melting and the OW IT"S HOT!

So they are thinking about optical circuits, and quantum computers (amazing really) and that kind of 1337 shiz.
 
One thing i think you be funny is. If you had a giant pole in space, say a million miles long, and you stood at one end only a few inches from it. If somehow someone managed to push that pole from the opposite end to which you were standing, how long would it take for the pole to hit you? Bearing in mind that this pole is made of something that doesn't buckle even under the mightiest pressure. Would that mean that at the very moment the person at the other end pushed it, you would know they were pushing it?

Sorry if that doesn't make sense, but its just one of the little things i ponder over.

EDIT: On the note of computers because thats what you were talking about. I think in isreal they manage to basically create the first DNA computer. I wont go into details because i dont understand it fully myself, but they got they did something where they got the DNA to do a thing, or something like that anyway. Il have to find the article again so i can explain it properly.


Quantum computers would be very cool. Basically you could have a sugar cube sized machine doing the processing work of the current tech made intoa computer bigger than a large house. Or something along those lines :)
 
It would happen instantly i think, no gravity, or mass or resistance of any kind, i think it would happen instantly.

As long as the person a the other end had some sort of force to push it with.
 
What about inertia?

Inertia is constant regarless of gravity. That is, it is just as difficult to throw a 15kg metal ball in space as it is on earth.

Therefore, this rod would have a lot of inertia. If the material were strong enough to not flex from the massive force needed to move it, a person on the other side of the force may see it move instantly. Although I wouldn't stand in front of that thing, cuz once it starts moving there's no stopping it!

BTW, the small size of the circuits is also a problem. The genetic and quantum computing research is definitely exciting! Though, it still at least 10 years away.

:bounce:
 
Originally posted by Zynaps
When a photon passes through glass it will not slow down. It will be absorbed by an atom and then released again some time later. Then it will collide with another atom and this will be repeated until the photon leaves the medium in question on the other side (depends on the medium ofcourse). Because of the time it takes for the absorbation and release it will appear as light slowed down and it did but the photons didn't. :) When the photon travels between the atoms it's speed is of course C.

Was just trying to keep it simple:cheese: but that's cool. Reminds me of the theories behind mirrors & how they work at the atomic level - now that's scary stuff! (too tired to try typing all that, but fun thread anyway)
 
Originally posted by Animal
You do realise that photons don't actually exist in the sense of particles, they are just representations of electromagnetic energy, it's known as wave/particle duality.
Therefore they can't age anyway, they maintain their energy state as long as they are present in the vacuum of space. Also the reason why they travel at the speed of light is because they have no mass, only momentum. They can have momentum even though they have no mass because mass and energy are basically the same thing. This has been *proven*.
The theory of massed bodies travelling at the speed of light is based on transforming our complete mass into momentum energy, which is not as hard as it seems according to some scientists.

Yep. For purposes of continuity with the 'myth' that I used to explain my previous posts, I kept with the theme of aging. Also I believe that anyone reading my post re:massed objects increasing in mass with increasing speed would realize with logical thinking that photons must not have mass at all, otherwise how would they travel at C?

I might have to go check up on the "momentum energy' thing, that sounds like an intriguing idea, thanks. :)
 
Originally posted by Farrowlesparrow
The funny thing about theories, is that we don't really know if they are right. But they seem to fit so for the time being it will do.

What I find continually stunning re: Einstein's theories is, that he has been proven mostly right. He not only came up with the theories behind relativity, but pondered (in his mind via thought experiments) the consequences of his theories. He said to the scientific community at the time, in essense, "All this stuff exists or is possible - black holes, worm holes, etc - it is up to you to discover the ways of finding them." And we have finally found black holes, + other stuff, and are working on still more of it. I think that is amazing myself. :)
 
Originally posted by Farrowlesparrow
One thing i think you be funny is. If you had a giant pole in space, say a million miles long, and you stood at one end only a few inches from it. If somehow someone managed to push that pole from the opposite end to which you were standing, how long would it take for the pole to hit you? Bearing in mind that this pole is made of something that doesn't buckle even under the mightiest pressure. Would that mean that at the very moment the person at the other end pushed it, you would know they were pushing it?

Sorry if that doesn't make sense, but its just one of the little things i ponder over.

Yes, thats exactly what I was saying. Lets say you have a pole that's 299 792 458 m long. So if somebody pushes it on the other end, you would only feel it a second later. BUT to you it would look like the person just pushed it this instant because light and all other information traveling from him can't travel faster then the pole itself.
 
Originally posted by Solidarnosi
This theory (part of Einstein's relativity stuff) was proven a long time ago, by simply building two atomic clocks; they put one on the ground in a building, put the other in a jet and flew it around the earth a few times - as fast as the jet could go, in other words, because what we are interested in here is the clock's SPEED relative to the 'stationary' clock. The clock in the jet, when brought back down, was younger than the clock on the ground.


Your close but kind of off. What the experiment was....was that there's the clock in the building....there's the clock on the plain. What Einstein was trying to proove was that gravity distorts time. Because of the fact that Time=Space. When space contracts (because of gravity) time speeds up. When space expands time slows down. He showed that being in this plane very high up (it went up REALLY high) would distort the flow of time we were use to on the surface of the earth. The tiny tiny change in gravity made a tiny tiny change in the speed of the clock. Making the plane clock a little younger than the earth clock. (but by only 1 or 2 nanoseconds)

This leads to a great joke I've herd from Steven Hawking, "If you tried to live longer by constantly flying in a plane for the rest of your life you will die years before you would have because of the airline food."


He also said how the french didn't want to call the balck hole a black hole.....they thought it sounded like somthing sexual.
 
The experiment was based on speed not altitude...
 
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