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/sci/ - Science & Math

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3096891 No.3096891 [Reply] [Original]

Could an object on the other side of the universe be moving away from us faster than the speed of light because of the expansion of the universe?

>> No.3096899

Yes and no. The distance between us and another object can be (and is) increasing at faster than the speed of light, but it wouldn't be quite accurate to describe that as "moving." It is more like more space being added between us, rather than either one moving THROUGH space.

>> No.3096902

no. nothing can exceed the speed of light

>> No.3096910

It can and it is. Everything more than 46 billion lightyears away from us is moving away from us faster than the speed of light due to expansion, which is why we can't see it (it is outside of the "observable universe").

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

>> No.3096920

>>3096902
/sci/'s resident genius strikes again.

protip: if you don't know anything about the topic, stfu. it's simple.

>> No.3096933

>>3096902
Idiot detected.

>> No.3096943

>>3096920
>>3096933
Einstein would like a word with you.
http://www.physorg.com/news12084.html

>> No.3096945

>>3096920
Then she would never be able to post.

>> No.3096949
File: 69 KB, 500x378, Wikipedia_cat.jpg [View same] [iqdb] [saucenao] [google]
3096949

>>3096910
How about finding an ACTUAL source of information next time?

>> No.3096950

>>3096943
Einstein was a faggot. He'd be lost in the physics of today.

Also: Tits or GTFO

>> No.3096952

>>3096945
That's the idea.

>> No.3096956

>>3096949
>herp a derp, wikipedia is stoopid cus you can just change it lol

Person living in 2003 detected.

>> No.3096958

>>3096902
i know things cant travel FTL, but technically according to >>3096910 things are moving faster than light relative to us?

>> No.3096959

>>3096943
>According to Einstein's theory of special relativity, published in 1905
>special relativity, published in 1905
>published in 1905
>1905
Do you know how science even works?

Also: Dark Energy, dumb ass.

>> No.3096961

>>3096943
>The object doesn't have to be moving through space at all
>The space itself is expanding, moving the object away
>did I get the high score?

>> No.3096962

>>3096961

Yup, an object receding at FTL due to expansion does not even contradict general relativity.

>> No.3096964

>>3096902
>>3096943
http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/FTL.html

Herp derp.

>> No.3096965

>>3096959
the age of a theory has no effect on its veracity. Einsteins theory is over 100 years old, but it has still not been proved wrong, and since then, more physical evidence has been found to confirm his theory, but none to disprove it.

>> No.3096974

>>3096965
>She still doesn't understand that's irrelevant in this conversation

>> No.3096972

>>3096965

See
>>3096961
>>3096962

>> No.3096973

>>3096950
>>3096950
>>3096950

Bollocks. Einstein would kick ass in any time period you threw him into and run off with your mother while you kept screaming fagoot fagoot. fucking moron.

>> No.3096980

>>3096943
>>3096902

curious.astro.cornell.edu/question.php?number=575

And here is an answer saying you are wrong

>> No.3096983

>>3096965
You're right, Einstein is still correct. But objects moving FTL due to an expanding universe doesn't contradict general relativity.

The question has been answered. You can delete your thread now before it turns into a tripfag shitstorm.

>> No.3096987

>>3096974
moving away faster than the speed of light from us =/= travelling faster than the speed of light itself.

>> No.3096996

>>3096983
isn't my thread. but this is quite interesting...
an object traveling at 51% the speed of light one way, and an object travelling 51% the speed of light the other way will be travelling faster than the speed of light relative to each other, and as such, cant see each other at all
MIND
FUCKING
BLOWN

>> No.3096998

>>3096956
>person with a shred of rational thought detected
FTFY, bro. But here's a tip: adding "herp" and "derp" does not automatically make you right.

>> No.3097005

>>3096899
First answer is right answer.

>> No.3097029

>>3096983
Why is space exempt from the limit c?

Wouldn't "expansion" still be a form of acceleration? Was it always expanding? If not, then doesn't this imply that the expansion had to, at least at some point in the past, accelerate from STL to FTL?

I'm not claiming to have knowledge on this by the way, I am asking seriously (and not the same faggot as earlier who was arguing).

Also how do we know that "space is expanding faster than light" at 46 billion light years and beyond" and that it's not just that Einstein was wrong and shit's moving faster than light?

Can the "expansion of space" be empirically observed in a lab? How is the experiment/observation performed?

If space is an actual thing that can expand, then why isn't it bound by the laws of Einstein's theory which says that nothing can accelerate from moving slower than light, to faster than light?

>> No.3097039

>>3096996
I hate you

>> No.3097040

>>3097029
<span class="math">
( a ) + ( -a) = 0
[/spoiler]

>> No.3097041

>>3097029
loaded post is loaded

>> No.3097046

You know, I've never ever payed much attention to tripfags... but holy fuck is EK stupid.

>> No.3097055

>>3096973
>run off with your mother
Unlikely. My mother isn't a blood relative of Einstein's.

>> No.3097056

>>3097039
why?
>>3097046
Am I? I agreed with the first post btw.

>> No.3097057

>>3096996
>an object traveling at 51% the speed of light one way, and an object travelling 51% the speed of light the other way will be travelling faster than the speed of light relative to each other, and as such, cant see each other at all

If you don't understand even the very basics of relativity, why do you keep replying to this thread?

>> No.3097065

>>3097057
I do understand basic relativity. am i incorrect?

>> No.3097066

>>3097029
http://www.youtube.com/watch?v=7ImvlS8PLIo&feature=player_detailpage#t=502s

He explains the idea very clearly here

>> No.3097070

>>3096949
The article is correct.
>>3096943
>>3096950
>>3096987
We understand the expansion of the universe FROM Einstein's theory of GENERAL RELATIVITY, not Special Relativity. The rate of expansion (or contraction) of space is not limited to the speed of light. Only the speed of an object moving through space is limited as viewed by another object IN THE SAME LOCALITY of spacetime, that is, ignoring any expansion/contraction of space, to the speed of light.

When space itself expands or contracts relative to another part of space faster than the speed of light, that is what constitutes an event horizon. One instance is near the singularities of black holes, where space moves away from us faster than the speed of light towards the singularity. The other instance is the edge of the observable universe, where space likewise moves away from us faster than the speed of light.

>> No.3097077

>>3097065
>I do understand basic relativity
>an object traveling at 51% the speed of light one way, and an object travelling 51% the speed of light the other way will be travelling faster than the speed of light relative to each other
>I do understand basic relativity

Die in a fire.

>> No.3097084

>>3096987
You did not answer OP's question. That is why everybody is calling you stupid.

Space can expand faster than the speed of light. Is space nothing? No.

>> No.3097087

>>3097077
[sarcasm] that was really helpful [/sarcasm]
explain it then, faggot.

>> No.3097090

>>3097029
Space is the manifold inside of which the laws of physics apply. The c limit is a property of those laws. The stretching and compressing of the manifold itself is a completely different thing.

>Also how do we know that "space is expanding faster than light" at 46 billion light years and beyond" and that it's not just that Einstein was wrong and shit's moving faster than light?
This is contingent on General Relativity being right. There is a lot of evidence for GR being right. But like all science, this is an interpretation of observational data based on the models that have been proven by other observational data.

>Can the "expansion of space" be empirically observed in a lab? How is the experiment/observation performed?
You can't really do astrophysics in a lab. The universe is the only lab. But you can make predictions, like the prediction of the CMBR. When that was discovered, that pretty much proved that space was expanding.

>> No.3097091
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3097091

>>3097084
>Is space nothing? No.
er..yeh it is.

>> No.3097092

>>3097087
Go read the sticky, retard. God knows how much I detest you EK

>> No.3097095

>>3096996
I hope to god you're trolling.

>> No.3097096

>>3097091
Boy, you are stupid.

>> No.3097100

>>3097096
Even other tripfags know exactly how fucking moronic you are, EK.

>> No.3097101

In modern physics, no. In Quantum physics, yes and no. No object will exceed the speed of light on our world or 3rd plateau. On the 4th plateau physics as we know it ceases to work and new laws, quantum laws, come into play. The easiest example it a sensory filament in every persons eyeball. This filament moves from point A to point C and back without every passing though point B
(ll( A-----B-----C)
This can only happen if an object moves along the 4th plateau. It is not exceeding the speed of light but rather taking a "short cut" allowing it to travel a distance along the 3rd plateau faster than light could.

>> No.3097103

>>3097091
laughingwhores.jpg

Get out of here, you dumb zoologist furry.

>> No.3097107
File: 2 KB, 126x124, idontthinkso.jpg [View same] [iqdb] [saucenao] [google]
3097107

>>3097092
[sarcasm] yes, because i am really likely to go and read a 660 post sticky... [/sarcasm]

>> No.3097108

>>3097087
http://en.wikipedia.org/wiki/Velocity-addition_formula

You should at least take a high school physics course before you start giving "answers" in physics threads.

.51c + .51c = .81c

>> No.3097113

>>3097107
And we are really likely to explain a branch of PHYSICS to a retarded zoologist? You fail at your own subject let alone a more complex one like relativity.

>> No.3097115
File: 29 KB, 512x384, notsureifstupid.jpg [View same] [iqdb] [saucenao] [google]
3097115

>>3097108
>51 + 51 = 81

>> No.3097117

>>3097057

You are incorrect.

<span class="math"> v = \frac{v_{1}+v_{2}}{1+v_{1}v_{2}/c^{2}} [/spoiler]

And again, please stop posting
sage

>> No.3097128

>>3097115

Hilarious how EK remains sure about how right she is when everyone else continuously proves her wrong time and time again.

>> No.3097125

>>3097115
>asks for the science
>calls the science stupid

>> No.3097122

I hope you've been saving all the threads you've ruined in the last couple of days, EK. Might come in handy next time you wonder why some people aren't exactly fans of yours.

>> No.3097127

>>3097117
was meant at >>3097065

fuck you EK

>> No.3097132

>>3097115
EK confirmed for troll/stupid.

He's doing Lorentz velocity addition. The "+" is an abuse of notation, I'll admit.

>> No.3097133

>>3097128
Ek is a "woman." It is to be expected with that marble-sized brain.

>> No.3097135

>>3097115

See, you give a wrong answer and as soon as you realize you're wrong you start acting intentionally stupid, and in a few posts you're going to tell us you were trolling the whole time in order to save face. THIS is why everyone hates you.

>> No.3097137

>>3097115
First off, the sticky's first post contains all the relevant information.

Second, with time dilation and mass increase as you approach relativistic speeds, the totals change, decreasing more and more so that objects with "rest mass" can never approach the speed of light or even appear to travel at light speed relative to each other. But you knew that already because you "understood relativity", right?

>> No.3097139

>>3097132
It gets the point across.

>> No.3097145

>>3097065
>I do understand basic relativity. am i incorrect?

Wikipedia articles don't count.

>> No.3097143

>>3097090
Thanks for your answers, I have a (admittedly barely) better understanding than before.

So "space" is an 'ether' so to speak, it is the fluid of everything, the toolbox itself, and is not bound by the laws of physics, but rather is what imposes them through its own nature.

If that's the case though, I have another question.

So space is expanding faster than light, and so we can't see past x distance because it's moving too fast for light to get to us, but here's what I don't get.

Let's say I shine a beam through expanding space, why can't I see it anyway? Just because space is expanding faster than light, it's actually space that's expanding, so that light shouldn't seem to be different to me, the light would travel along the space just the same, but the space is expanding.

How does the space escape the light beam just because it's moving faster, since the light is in the space? I'm sorry if this question is worded shitty, so here's a hopefully better analogy.

Let's say I have a rubber band, and on the rubber band I draw a line with sharpy (and i get it with a real thick coating), I then stretch that rubber band and at whatever speed I stretch it, the line I drew also expands.

Why isn't this the case with space?

>> No.3097147
File: 3 KB, 126x121, failtroll.jpg [View same] [iqdb] [saucenao] [google]
3097147

>>3097125
>>3097128
>>3097132

so if i am standing on a truck going 51 miles an hour, and i point a police speed radar gun at another truck moving in the opposite direction at 51 miles an hour, you think the speed would register at 81?
it would be 102 miles an hour, i know how velocity works so you fools can't troll me.

>> No.3097150

>>3097143
Also, the line I drew would pixelate.

Does pixelation result result from expansion of space/is there such a thing as pixelation in nature?

>> No.3097156

>>3097147
You are either trolling super-hard or you are even dumber than I thought.

>> No.3097157

>>3097147
SHUT
THE
FUCK
UP
ALREADY
YOU
PERVERSELY
DUMB
CUNT

>> No.3097168

>>3097147
see:
>>3097135

You could just admit you were wrong and that you learned something, but you insist on shitting up the board instead. Thanks for making /sci/ a worse place than it already is.

>> No.3097169
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3097169

>EK makes valid post
>instead of anons actually using this opportunity to share knowledge, do science, and discuss the topic reasonably they just whine, spout insults, and suggest she leave
>stay classy /sci/

>> No.3097172

>>3097147
ok OP here, this has turned into some kind of EK dumbass-fest where everyone bitches about EK and in return 'she' tries to troll back.

EK you just lost the respect of yet another sci dweller, take off the fucking trip

>> No.3097172,1 [INTERNAL] 

>>3097143
I wouldn't go as far as to say that spacetime isn't bound by the laws of physics. It is, but it is in a different context than the movements of things within spacetime. The laws of General Relativity say how spacetime gets transformed depending on what's going on inside it.

I'm not sure I'm following your other question or analogy, but let me explain this way. Let's say we shoot a laser out towards the edge of the observable universe. It takes time (from our perspective) for that laser light to travel. After a time T it has gone through X amount of space, and has Y amount of space left to get to the edge of the observable universe. However, in that time T, X has expanded and Y has expanded. Since X has expanded, the light is now actually further away from us than the speed of light would predict, and it has red-shifted. But since Y is so big, it has expanded by a larger amount than the light has traveled, so the light is no closer to reaching the edge.