2 science questions -

[.pcbrainbuster]

Sup guys,

I have to more science qestions -

1) How does light even move? I refuse to believe it moves itself.
2) How many types of forces are there in existence? I'm begining to think the answer is infinite because it takes atleast 1 force to create another(not sure though)...
3) Since the closet start(apart from the Sun) is around trillions of light years away doesn't this mean that our night sky is outdated? Because by the time the light gets here the start would have died/blown up...

Thanks.

[.pcbrainbuster]

Whoops I just realized what the title says against my last post :p

[Marc G]

1) How does light even move? I refuse to believe it moves itself.Light moves just light radio waves move.
2) How many types of forces are there in existence? I'm begining to think the answer is infinite because it takes atleast 1 force to create another(not sure though)...There are only 4 fundamental forces in modern physics: weak nuclear force, strong nuclear force, gravity and electromagnetism.
3) Since the closet start(apart from the Sun) is around trillions of light years away doesn't this mean that our night sky is outdated? Because by the time the light gets here the start would have died/blown up...The closest star is not trillions of light years away. The closest star to our sun is Proxima Centauri which is only 4.2 light years away. But you are correct. If you are watching a star in the sky that is 4.2 light years away, the light you are now seeing is 4.2 years old. So if you are watching a star that is billions of light years away, the light is billions of years old and the star might indeed have exploded in the mean time.

[MikeAThon]

Light moves just light radio waves move.
Through the ether, right? ;)

Mike

[.pcbrainbuster]

Weak/Strong Nuclear Force? I thought you were gonna say something like Friction. Please expand what you mean while I search it up.

[Marc G]

The following page describes all the 4 fundamental forces:
http://en.wikipedia.org/wiki/Fundamental_interaction

[CBasicNet]

Through the ether, right? ;)

Mike

Ether exists? Really?

[S_M_A]

Notice the ;)

[cilu]

1) How does light even move? I refuse to believe it moves itself.
Light is an electromagnetic wave. Waves are the propagation of energy across space and time.

2) How many types of forces are there in existence? I'm begining to think the answer is infinite because it takes atleast 1 force to create another(not sure though)...
Four. And one of the main goal of physics today is to unify them into a single one. See the strings theory or the M theory (nobody knows what M stands for), but you have to be prepared to think in 10, 11 or 12 dimentions.

3) Since the closet start(apart from the Sun) is around trillions of light years away doesn't this mean that our night sky is outdated? Because by the time the light gets here the start would have died/blown up...
Well, the last part is correct. That's why some stars that we currently see on the sky might be already dead and gone.

Through the ether, right?
LOL. That was a good one. ;)

[.pcbrainbuster]

What is this whole ether thing, I don't get it :(

[Kheun]

Ether was thought to be the medium that fill up space and is required for light to propagate. Nowadays, we know that it is incorrect as we understand light travels though empty space.

[cilu]

What is this whole ether thing, I don't get it :(
Here it is some info about it http://en.wikipedia.org/wiki/Aether_theories.

PS: usually, it is spelled aether after the greek word.

[Krishnaa]

The light is same as other radio waves, with few more interesting properties. it travels in packets (or waves), can be understood as short ray of light. It can move through empty & all transparent matter.

The most interesting property of light is that, it has got the highest travel speed in the humans known universe and the speed is same for everyone (freaky...), I mean even for a person traveling with near light speed, it's very very hard to digest this but amazingly it's true and has been proven. Discovery Science had a very nice documentary on this topic.

Here is something more on it,

http://www.phys.unsw.edu.au/einsteinlight/jw/module3_weird_logic.htm

[olivthill]

Theoretically, you could go faster than the speed of light by taking advantage of quantum leaps, and in order to so, you would need to travel, not through empty space, but on the contrary through a very dense material.
The speed of gravitation is another subject that looks quite interesting. Some say it is the same as the speed of light. Personally, I .... don't know.

[.pcbrainbuster]

Discovery Science
I saw the program as well and I recall it talking about time travel as well.

I'm begining to think that light itself warps all the time, this is the only way I think light can cach up to you even though you're around the same speed.

Ether was thought to be the medium that fill up space and is required for light to propagate. Nowadays, we know that it is incorrect as we understand light travels though empty space.
Dark matter now seems to be the medium that is mostly around the universe now according to scientist.

Theoretically, you could go faster than the speed of light by taking advantage of quantum leaps, and in order to so, you would need to travel, not through empty space, but on the contrary through a very dense material.
As far as I know this means death, because no known material can go through a black hole without being disintegrated.

[CBasicNet]

Dark matter now seems to be the medium that is mostly around the universe now according to scientist.

Dark matter is just a theory, not proven yet. Some scientists proposed this theory because they tried to create computer simulations of our universe but failed because our universe doesn't hold enough mass to be as it is now. They believe dark matter which cannot be detected, is the missing mass.

Dark matter (http://en.wikipedia.org/wiki/Dark_Matter)

[gjs368]

Through the ether, right? ;)

Mike

And you can catch it with an ether net :cool:

[TheCPUWizard]

Ether exists? Really?

Definately.... C4H10O
basically two shots of pure alcohol and a water chaser.....

Also ether (aether) is still currently used in the mathematics to wave theory. Since a "Wave" is a (typically periodic) distortion or movement of "something" (tidal waves through water, sound wave through air (and some solid materials). The medium itself influences the propogation rated, damepening and distortion. Since light can also travel through a pure vacuum, this raises a bit of an issues....

[How well I remember trying to wrap my mind around this when I was 15 :) ]

[.pcbrainbuster]

Like Gravity can vibration also be infinity as long as there is a consecutive amount of medium?

[TheCPUWizard]

Like Gravity can vibration also be infinity as long as there is a consecutive amount of medium?

All of the forces are attenuated by distance and the menium. If it were not, we would all be "pulled" off of earth to the more massive planets and stars (especially the sum)