/sci/ - Science & Math

>>6750508
If we were moving that fast, wouldn't we be able to notice it via a shift in the wavelength of light emitted?

>>6750508
There are no preferred reference frames. We probably are moving at 0.9c with regards to some object in the universe.

>>6750508
how do we know that we all don't move at 0.9c relative to what?

We probably are moving that fast, in reference to something on the opposite side of the universe from us, due to expansion

>>6750508
Light moves at a constant speed in the vacuum, but not through matter.
Just saying.

>>6750508
I am not a physicist but it is basic logic to know that if we were so close to the speed of light, light would appear to be moving slower.

>>6750981
Yes, but depending on our speed our PERCEPTION of how quickly it is going can shift. If we were going .9c right now, then everything would appear slower to compensate so that light appears to move at the same speed

>>6750983
>I am not a physicist
and you proved it was your ignorant post. Learn about time dilation.

>>6750983
wrong.

>>6750983
Quite wrong, light is invariant under special relativity, meaning its speed is constant from any reference frame. Actually what you just said was completely contrary to what is actually the "basic logic" of relativity. Good job mate.

>>6750972
This

Your question doesnt make sense unless you give a point of reference

>>6750972
/thread

>>6751001
>Logic.
>Relativity theory.
Pick one.

>>6751073
Shut the fuck up faggot.

>>6751085
Epic meme! :^)

>>6750979
Each lightyear is expanding about 2cm / s.
For this to add up to c, 300000 km/s
you need 3*10^8 / 2*10^-2 lightyears
which is about 15 bn lightyears from us.
Not even close to the edge of the observable universe which is 46 bn ly away.

>>6750508
We are moving .9c, to an observer at the edge of the visible universe, some 12.42 billion light years away

>>6750983
This is why physicists, not normal people, are accomplished scientists that discover new stuff.

They aren't impeded by their common senses. The universe is large, there is no reason that it must work in your ideals that work on earth.

>>6751124
Edit:

We are moving at .9c to EVERY observer at the radial distance of 12.42 billion light years away from us.

>>6751132
>every observer.

One of them gets in their spaceship and starts moving at 0.9c relative to their planet towards us. He is an observer, and he doesn't move at 0.9c relative to us. What the fuck are you talking about?

Can we slow down light?

>>6751488

>>6751488
http://www.seas.harvard.edu/haulab/publications/HauPublications_All.htm

http://en.wikipedia.org/wiki/Cherenkov_radiation

Yes

And it was a very hot woman, ironic because she worked with bose-einstein condensates.

We're moving at lightspeed relative to light.

>>6751773
She doesn't look that hot to me.

http://en.wikipedia.org/wiki/Pavel_Cherenkov

>>6751124
>the edge of the visible universe
that is 46 billion light years away, get your facts straight anon

http://en.wikipedia.org/wiki/Observable_universe#Size

http://en.wikipedia.org/wiki/Observable_universe#Misconceptions

>>6751814
jej

>>6750508
What is frame of reference.
What is redshift (or theoretically blueshift)

Waves propagating, dude.

There may be a 0,0,0 in the universe, but no absolute frame of reference for light. It's like asking if there's an absolute frame of reference for a wave in the ocean. The frame of reference is from wherever the wave is created.

Think of fireflies. They're moving around, emitting light. Light is emitted, it's not an absolute.

>>6751856
that is the comoving radius, nobody thinks about the comoving radius

>>6750508
light moves at different speeds in different places. The speed of light people talk, they really mean the speed of light in a vacuum. The speed of light through say, air, is a bit slower. Don't know how much though.

>>6751930
That's how distance is measured in cosmology. Everybody thinks about it.

>>6750508

it depends on the reference frame

>>6750508
Everything does happen at c, dude. It just takes a while for every individual bit of a complete system to have finished happening to happen.

>>6751901
>There may be a 0,0,0 in the universe

No, dude. See, this is exactly the shit that Einstein was trying to tell you about.

>>6750508
Because to you you're standing still. Relativity is mainly meant to show that the speed of light in a vacuum is the same regardless of the speed you are moving at. If I am moving at 1/2c and a shoot a laser pointer with photons emitting at c they travel at c based on both my perspective and the perspective of another observer (who sees me going at 1/2c).

>>6752102
Same with sound waves. If you're running and shouting the sound still propagates at the speed of sound.

>>6752100
Einstein believed in static universe. As far as we Know the universe is flat.

>>6752121
>babby's first troll

>>6752122
Yes, but quatative values of time, energy and space are all relative.

>>6751787
Nope. Photons are not valid frames of reference. You wouldn't understand the math, but it's a divide by 0 thing.

>>6752153
>Photons are not valid frames of reference

Shiggity diggety dog, my nigger, [citation needed]

>>6752160
he's right. have you ever gone through the differential equations for this? just doesn't really add up.

>>6752170
If you're tracking a photon as a discrete object with velocity, trajectory and position, then it's no different than tracking any other discrete object with velocity, trajectory and position.

The math is the same, and you are full of shit.

>>6750508
light when in transit doesn't warp the fabric of space and time
matter when in transit does warp the fabric of space and time
matter creates a Doppler effect slowing time down around itself.
it is because of this that the energy required for speed acceleration is exponential

light speed though at the simplest is 1 planck meter per planck second
because of the Doppler effect the fabric of space time is foreshortened
in the direction of travel, meaning photons actually travel less higher-dimensional distance
when travelling ahead of near light-speed objects.

>>6752189
>being this wrong
cases involving things moving at c are a little different

>>6750920
this
/thread

>>6752189
Talk shit when you actually know what you're talking about.

>>6750508
With all the fake pop sci quotes on the internet I'm a bit skeptical about this one.

Did von neuman actually say this?