Light speed is not what we think.

Phew!
So no problems with parking or obtaining hard-core for building work.
Is it true that light bends because of a planet's gravity and would this
actually 'slow' it down?

Well, the interesting thing about gravity - and as you begin to understand General Relativity you come to realize this - is that it's not really a force. Gravity is actually an effect, caused by the distortion of time.

You are not being held to the earth by gravity, but by space-time distortion (crazy, eh?).

Imagine a base-ball. The classic example is that you throw the ball, and it comes down to earth because gravity pulls it there. If you threw it hard enough, it would circle the earth, always falling inwards, but never hitting the ground (so if someone says "you couldn't hit the ground!" say "wow! I never knew I was so strong!"). Now you have to take this idea, and kinda flip it on its head. The ball isn't being pulled towards the ground, it's more like the space in front of the ball is curving upwards to become the ground. The earth is changing the direction of the ball by 4-dimensionally displacing where the ball is going.

This is why light is affected by gravity. It's not that light has mass, and so is pulled towards an object of mass, it's more like the mass changes the direction that the beam of light is going in. The space in front of the light is now a different space.

Sounds like you're interested in this stuff! I'll keep trying to answer to the best of my abilities!

Gee, now my head hurts!
I think I'm gonna have to re-read your answer about the gravity 'thing',
it's first time I've heard of it that way!
Anyway, following the original thread (trying to):

The speed of light, is it relavent that it's the fastet 'thing' we know?

The crystal that the scientists used (the guys in the mine), how did that
work? They were supposedly capturing the 'spark' from a colliding dark
matter particle and something else... I'm sure they said a hydrogen particle.

Here's one for the pot... could we ever use light as an energy to get us across the
galaxy and beyond? Oh and is it a beam of energy?

It's your turn for the headache!!

Hehehe! It's interesting that you bring up SNO (the guys in the mine), because SNO stands for Sudbury Neutrino Observatory... and guess what city I'm in

That's right! I'm a Sudburian of Northern Ontario, Canada!

What SNO accomplished was looking for was Neutrinos (those WIMPs I was talking about). Other Neutrino observatories had been produced around the world, looking for how many neutrinos occupy space. However, the innovation of SNO was that it detected ALL kinds of Neutrinos.

At Science North, a science-centre in Sudbury, there is an "object theatre" (a theatre that uses pre-programmed props) that teaches about SNO and Neutrinos. It words it the best in that, like Ice Cream, there's different "flavours" of neutrinos. That's why each neutrino observatory before SNO didn't detect the same number of neutrinos.

However, the "crystal" your talking about isn't crystal at all...

SNO utilizes water.

Not just any water, heavy water. Heavy water has an extra neutron in it, and is actually noticeably heavier (pick up two bottles of it, the heavier one is heavy water). That extra neutron "thickens" the water enough that neutrinos passing through it have a better chance of interacting with the particles in the water.

When the neutrino hits the neutron, it releases a flash of light. Sensitive photo-receptors placed around the tank then pick up this event and transfer all information in the light to a computer.

What has SNO discovered? Well, it answered the question: Do Neutrinos Have Mass? The answer is yes - but in amounts smaller than ever thought possible. It also detected that there's a LOT of neutrinos flying around. Here's an example.

Hold out your finger.

1

2

3

About 5 BILLION neutrinos just passed through your finger. Most of them probably didn't hit a thing. They're so tiny, and interact with matter so infrequently, that they almost don't exist.

SNO continues to operate and is now looking for Cosmic Rays and other WIMPs. It hopefully will be of great use in further study of dark matter.

And how do I know so much about SNO? Well, I actually volunteered at Science North for a summer, and I operated that object theatre. I was stationed in the space section, and it was pretty cool.


Now, as for using light as a means of travel. You would have to change your mass into 100% energy (at 100% efficiency), not blowing this continent up in the process, accumulate your energy and send it in a specific direction, and then somehow have something at the other end recieve all of your energy and transfer it back into 100% matter at 100% efficiency. Not to mention that all the information about you would have to remain unscrambled in the process.

In other words, the chances of using it like that are nill. The closest way to using light as a means of travel is the solar sail, and a solar sail of appropriate size would be too large, and too fragile.

AArghh! forgive me it's just aquiring new info has this sort of effect
on my head.

The problem I always have is that I bring 'the street' view of anything
to do with physical mass and I must remember to leave that at the door
next time.
Of course, if an object is small enough, it can pass through another 'solid'
object by passing between the spaces from atom to atom. Is that it?
I know I'm playing catch-up here.

Originally posted by IronMan
Of course, if an object is small enough, it can pass through another 'solid'
object by passing between the spaces from atom to atom. Is that it?
I know I'm playing catch-up here.

Precisely.

This may surprise you, but the majority of the universe is made up of "empty space". First, there's the space between molecules. It's vacuum, it's empty. Then there's the molecules themselves. They are atoms.

Imagine a stadium... a big one. If the stadium is an atom, the a football player's helmet at the center is the nucleus of the atom. The space inbetween is empty.

In fact, electrons are even tinier than the nucleus, and they only fly around the nucleus at nearly the speed of light . So it's like a marble in the top part of the bleachers.

Neutrinos would be even tinier... like specks of dust.

So, as you can see, there's a LOT of empty space out there.

That's where the core of a Black Hole is different. It's so tiny because all that wasted space is now filled with the very essence of matter - whatever that may be. This singularity may be smaller than a marble - but the amount of mass it contains is huge, and so the Event Horizon it creates is much larger than itself.

Sorry for the delay, but there's only so much ram in my 'noggin'
before my ears start bleedin'!

So when you say space, you mean the area between the 'outer'
part of the atom and it's 'centre' is what?... void, empty, without?

Jeez Louis,... Oh re all atoms the same size?- this one's from a co-worker.

By space, I mean emptiness - utter and complete vacuum, a void of nothingness.

Of course, stuff will go through there. Like photons, neutrinos, etc - but it is remarkably empty of anything at all.

Are all atoms the same size? Roughly. The big ones are just bigger helmets, eventually some are the size of the football players themselves, and the biggest ones may be the coach buses they ride in.

However, the atom itself is then bigger too. You have different orbits of electrons. Only 2 electrons fit inside the first orbit. Other orbits are the same distance from the first as the first is from the core. The really big atoms have 4 or more orbits of electrons!

Now, you want something to REALLY start warping you and your co-workers brains?

When electrons "jump" orbits, they don't pass through all that empty space inbetween. They disappear from their orbit, and reappear instantaneously in a higher orbit. The forces of nature do not allow the electron to exist at any point inbetween the orbits.

The current going theory is that they move 4-dimensionally to the outer orbits, going along a path that exists, but cannot be seen. This is why it appears to pop in and out of existance, because it moves 4-dimensionally "up", then moves 3-dimensionally across, and finally, 4-dimensionally "down".

Exactly how that works, you need to research String Theory - and I'm not that good... and neither is String Theory for that part (it's just a theory, with many different parts, that haven't been unified togeher yet... but we're getting there. I beleive String Theory to be correct).

Originally posted by Yarium
By space, I mean emptiness - utter and complete vacuum, a void of nothingness.

Of course, stuff will go through there. Like photons, neutrinos, etc - but it is remarkably empty of anything at all.

Er... okay.
I don't understand (and neither does my co-worker) the 'popping in and out of existence of their orbits. Where do they go? Must investigate.
I realise now that I'm not playing catch-up, but sitting quietly in the stand meekly waving a small flag with Einstien's head on it.

mod edit: shortened quote

[edit on 12-1-2006 by sanctum]

Alright, let's see if I can shed some light on that.

I take it you don't understand the 4-dimensional "up" idea. So I'll do what Einstein does. I'll bring it down to a level we can see and visualize.

Imagine you're a 2-dimensional square. You have width, and length - but no height. You also live in a universe which is also, seemingly, 2-dimensional. You look out, and it's a never-ending horizon that goes on forever.

However, you're so tiny, and the universe is so big, that you don't see that the universe actually curves, ever so slightly, into a big ball. So, while you're trying to wonder where the "center" of the universe is, you don't realize that the center doesn't exist on the same plane of existance as you do. The center would be the middle of the ball - but you can't get to it.

Let's now say that one day you're sitting in your 2-dimensional house. You don't have a roof because "up" doesn't exist to you. However, above you is a sphere of equal intelligence. The sphere might shout down to you, and you may hear it, but you couldn't see it. The sphere could go below you and shout, and you may hear it, but not see it. Now, imagine that the sphere were to pass through from "up" to "down". Out poor 2-dimensional square friend would see a circle that would grow, and then shrink - from nothing, and into nothing again.

Of course, it's just percieved nothing. The space exists - but not like you, the square, can imagine, grasp, or see.

Now, take every word using "dimension" in that, and add 1. Now you're 3-dimensional, and there would be a 4-th dimension that exists, but you can't see, and thus can't imagine. It's essentially "up", but it isn't at all. Most likely it's "forward" and "backward" through time. If something moved 4-dimensionally, it would seemingly disappear, and then when it came back "down" to our dimension, it would seemingly reappear.

That's what's happening to our friend the electron. It moves through space that we can't even imagine to exist, and then comes back.

Moreover, our universe might curve around 4-dimensionally. This means that if you were to travel in a perfectly straight line from earth, and earth stayed still, that eventually you would probably get back to earth. You would have no idea how you got back to earth, since - to you - you travelled perfectly straight, but the curvature of the 4-dimensional universe would make it so.

So, like the surface area of a sphere, the universe can have a limited size, but you could travel in it (or around it) an infinite number of times, making it appear to be infinite in length.

Ah Ah!
I understand now... I think.
So anyway, the documentary about these 'supposed' dark matter hunters, indicated
that there may well be another universe, but in another dimension.
I think it had something to with Hubble, the prof?

So now as we say, "my head's in bits" and it's highly unlikely that I'll get any sleep tonight!

The problem I have is that I'm almost ceratin I heard someone discuss Tachyons in a scientific programme, but I once mentioned it, via email, on a radio station and said station
was inundated by callers saying that I lived in a fantasy world of Star Trek!
Maybe I misheard.



[edit on 11-1-2006 by IronMan]

Originally posted by Yarium
Actually, the problem with your thinking is that you're thinking on the basic levels. You're thinking the way people USED to think about light. It wasn't until Einstein's General Theory that he talked about the problems with trying to achieve light speed and the warping effect it has.

But, just to point out to you, they've done experiments on time dialation. They've created INCREDIBLY precise clocks that can measure millionths of seconds of time. They put two of these clocks in sinc, and then placed one of them in orbit (either on a satellite or on the Space Station - I believe the latter).

When they brought the one that was in orbit back and compared it to the one that stayed on earth, they discovered that the two clocks were ACTUALLY off-sinc, something that would have been considered impossible before Einstein (had such clocks existed back then). This is because the Space Station / satellites orbit the earth at pretty high speeds. Even though they're minute compared to the speed of light, any movement will experience these kinds of time dialations.

Since it worked and is observable at the small scale, we must assume the same is true of the large scale, and that approaching the speed of light becomes more and more difficult the closer you get there.

So 55 000 000mps is the universal speed limit for objects with mass. Of course, objects without mass don't necessarily follow this quite the same. Such as gravity. What's the "speed of gravity"? If a planet moves through a solar system, at what speed does it's change in position change the gravitational affects on other planets? Is it instantaneous? Or is there a graviton that carries it? or perhaps a "gravity wave"? If these things exist, is there then a way to control it?

I agree with this. You're jumping to conclusions in seconds on a matter it would take hours for an experienced physicist to explain. You did not consider the thousands of other factors tied in with this subject. Besides that, we will never really know until it is tried. And it is possible to effectively "stop time" if you could travel fast enough that everything around you would be going at such a signifigantly lower rate than you, that you could do in seconds what it would take someone not traveling at this speed. This is assuming that you are somehow tied into the speed at which the craft(most likely) that you are in is going. Then it is possible. This is all theoretical, of course. But please, leave the complicated subjects to physicits who know what they're talking about.

Originally posted by Yarium
You're quite right there IronMan. If it doesn't give off any light of its own, it is considered "dark". Something which also does not reflect light would equally be considered dark.

Now, apply this to the idea of Dark Energy which has been thrown around the scientific community at large. It would be a type of energy that is not easily observable. In all truth, I think Dark Energy is a load of crock, but it has a number of devote believers, and so needs to be investigated.

hmmm

so says you says i!


Darkmatter

dark matter is not all matter that does not give of light, infact its about electromagnetic radiation!

[edit on 11-1-2006 by NeonHelmet]

[edit on 11-1-2006 by NeonHelmet]

FYI, Electromagnetic Radiation IS light. It also can be X-rays, microwaves, Infrared, Ultraviolet, Cosmic Rays, Radio Waves, etc.

Originally posted by Yarium
FYI, Electromagnetic Radiation IS light. It also can be X-rays, microwaves, Infrared, Ultraviolet, Cosmic Rays, Radio Waves, etc.

Perhaps I could have put it in a better way then.

To my knowledge electromagnetic radiation is not the energy it self but the wavelength or frequency the energy works in, and yes x-rays, microwaves, infrared, radio waves etc are all energy, but not light.

Photons is light and photons exist in many things, but that do not make everything its in;n light, yes there are photons in electromagnetic waves. IMHO, it is not light, photons are (light) electromagnetic radiation is not. (Light)

I think that perhaps it has something to do with my point of reference; it could very well be biased.

I contain water but I am not the ocean.

Anyways the point I tried to make was that dark matter is not all matter. The dark matter consists of about 99% of the universe, and works the opposite of gravitational forces. It also has the property that photons go through or around it!




[edit on 12-1-2006 by NeonHelmet]

Whoa, now you're really going off what happens.

It's not that photons go through or around it, it's that light interacts with it differently, or the light/energy that is reflected is insignificant next to the light given off by stars and other celestial phenomenae, as to make it impossible to see the relfected light.

A perfect example of this...

Have a freind hold a match and a good, strong, flashlight. Have him strike the match, turn on the flashlight, and hold the match right next to the flashlight while you look in his direction. How many lights do you see?

Chances are (if done correctly, or with a good enough flashlight), you will only see one light. The light from the flashlight blankets out the light from the match. The match-light is still there, it just doesn't register comparatively next to the flashlight.

This is why a planet is considered Dark Matter. It's "dark" because we can't see it through the electro-magnetic spectrum (of which visible light is a part of).

Now, WIMPs don't act with light normally because, being so tiny and sparse, they are often not "hit" by a photon of light. So yes, the light goes around them, or through them (perhaps like an electron, it absorbs and releases the energy).

Here's a website you should read to get a full understanding of Dark Matter:

What do scientists look for when they search for dark matter? We cannot see or touch it: its existence is implied. Possibilities for dark matter range from tiny subatomic particles weighing 100,000 times less than an electron to black holes with masses millions of times that of the sun (9). The two main categories that scientists consider as possible candidates for dark matter have been dubbed MACHOs (Massive Astrophysical Compact Halo Objects), and WIMPs (Weakly Interacting Massive Particles). Although these acronyms are amusing, they can help you remember which is which. MACHOs are the big, strong dark matter objects ranging in size from small stars to super massive black holes (1). MACHOs are made of 'ordinary' matter, which is called baryonic matter. WIMPs, on the other hand, are the little weak subatomic dark matter candidates, which are thought to be made of stuff other than ordinary matter, called non-baryonic matter. Astronomers search for MACHOs and particle physicists look for WIMPs.
Astronomers and particle physicists disagree about what they think dark matter is. Walter Stockwell, of the dark matter team at the Center for Particle Astrophysics at U.C. Berkeley, describes this difference. "The nature of what we find to be the dark matter will have a great effect on particle physics and astronomy. The controversy starts when people made theories of what this matter could be--and the first split is between ordinary baryonic matter and non-baryonic matter" (10). Since MACHOs are too far away and WIMPs are too small to be seen, astronomers and particle physicists have devised ways of trying to infer their existence. eclipse.net

mod edit to use "ex" instead of "quote"
Posting work written by others. **ALL MEMBERS READ**



[edit on 12-1-2006 by sanctum]

Ok mate ill read up on it and return later.


though im pretty sure im correct.


a little thought for fun while im away.

This is why a planet is considered Dark Matter. It's "dark" because we can't see it through the electro-magnetic spectrum (of which visible light is a part of).

How will you explain that i just saw mars 4 days ago, from my balkony? if it cant reflect light? how did i see it?

[edit on 12-1-2006 by NeonHelmet]

Originally posted by NeonHelmet
How will you explain that i just saw mars 4 days ago, from my balkony? if it cant reflect light? how did i see it?
[edit on 12-1-2006 by NeonHelmet]

Firstly, because it can reflect light. The reason you can see a wall is because the light is reflecting off of it.

So, you can see Mars because it's reflecting enough light so that you can see it. We're in the same solar system, and thus the flash-light experiment would need to be repeated, but with the flash-light to your back, and another guy holding the match to your front. You can see the match now because it's far enough away from the flash-light to be visible.

It's because the planets that we're viewing are so far away that we can't see them. This is why you can't see Pluto with your naked eye - it's just too far away.

Now, a way to see Pluto is through a telescope (a very powerful one at that). The telescope will "zone in" on the light that's there, and so it becomes easier to see Pluto.

An interesting telescope is the Interferometer planet-finder that was in development (I'm not sure of it anymore - but I doubt they cancelled it). Basically, using the theory of interferometry, it cancels out the light of a star. More or less, using the match-light and flash-light example where the two are right next to each other, it's like turning the flash-light off. Seeing the planet is now ean easy affair.

Please keep this discussion up, my son and I are learning a lot!

Do black holes REALLY REALLY exist?
Is there any proof that other dimensions exist?
Finally, is there an edge to the universe?

Originally posted by IronMan
Please keep this discussion up, my son and I are learning a lot!

Do black holes REALLY REALLY exist?
Is there any proof that other dimensions exist?
Finally, is there an edge to the universe?

I'm glad to see that I'm getting your son interested!

Answer 1: Yes, they exist, if by exist you mean that there's mass in the area where a Black Hole is said to be. If you mean exist as in... well.. EXIST. That'd up to debate. I'd have to say yes, they exist. I'd say that it's matter brought down to its very basic element (whatever that is), and there is NO space inbetween these carriers of mass.

Answer 2: Depends what you mean. If you mean dimensions as in alternate universes, then no. The closest thing would be the photo-electron effect, where electrons behave like light. The classic experiment with light is to set up a light source, then a thin slit for light to come through, then an open area, then two more slits for light, then another open area, then a wall. You'll notice that the light forms "bars" of:

I_I_I_I_I (where "I" is illuminated, and "_" is dark)

They did the same thing with electrons, shooting them out one at a time. Odd things began to happen as it formed the same pattern, which meant that SOMEHOW the electrons were acting like a wave, which is impossible since they're matter and were being sent through the "slit" one by one, and so couldn't tell where the other electrons were going.

The proposed theory is that the electrons (remember that they shift into another spatial dimension when they go between orbits) were interacting with electrons from other alternate universes, where the electron went through another slit. The average is what appears at the end, which is why it looks like it behaved as a wave.


Now, if you mean other spatial dimensions, then the electrons changing orbits is the best proof we have of this, but space-time could also be said to be an effect of this. So, yes.


Answer 3: According to most astronomers and theorists, no. Here's why.

Take a basketball. Draw a dot on it. This dot represents your placement in the universe. If you then draw a line from that dot in any direction on the ball, you will never reach an edge. You'll just keep circling the basketball.

If the 4th spatial dimension indeed exists as it is believed to, then the same thing happens in our universe, except that it's a strange kind of 4-d sphere that we could circle an infinite number of times without coming to an edge. This is also why there's no center to our universe - because it doesn't exist in 3-dimensional space.


Here's my theory:

The "center" of the universe is the Big Bang - the point from which it all began. We are living in but one of a near-infinite number of universes, where different chaotic events (events with no predictable outcome) occur in each one. Our universe is but part of this grand supra-verse. It is because of this connection that so many things which are thought to be impossible sometimes happen.

For example, have you ever had a dream which then came true?

It's happened to me many times (though with much less regularity now), and has helped me to avoid arguments and dilemmas.

So, on one hand I said to myself, there must be Fate - since how could I know what would happen (often of places and people I had never met at the time of the dream - roughly 6 months before the event)? But then, there couldn't be Fate, because I would change what would happen in my dream, and what happened in real life (due to my interjection... before this it became so bad that I used to say "Man, I'm having Deja-Vu" whilst in my dream before the Deja-Vu).

Now I believe that my soul (many more theories have I on that) travelled to another quantum universe which was exceedingly similar, but not entirely, like my own. Since it was another "me's" universe, it was not fate, but instead what was simply likely to happen. Whether I let it happen that way or not was up to me, since my future in THIS universe is not yet determined.